Resolve "Trash (never delete anything)"

backend/requirements/dev.txt

@@ -10,3 +10,4 @@ watchdog==1.0.2
 argh==0.26.2
 black==20.8b1
 django-capture-on-commit-callbacks==1.4.0
+pyinstrument==3.4.2

backend/src/baserow/api/applications/views.py

@@ -71,7 +71,7 @@ class AllApplicationsView(APIView):
 
         applications = Application.objects.select_related(
             "content_type", "group"
-        ).filter(group__users__in=[request.user])
+        ).filter(group__users__in=[request.user], group__trashed=False)
 
         data = [
             get_application_serializer(application).data for application in applications

backend/src/baserow/api/trash/errors.py

@@ -0,0 +1,26 @@
+from rest_framework.status import HTTP_400_BAD_REQUEST, HTTP_404_NOT_FOUND
+
+ERROR_TRASH_ITEM_DOES_NOT_EXIST = (
+    "ERROR_TRASH_ITEM_DOES_NOT_EXIST",
+    HTTP_404_NOT_FOUND,
+    "The requested trash item does not exist.",
+)
+
+ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD = (
+    "ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD",
+    HTTP_400_BAD_REQUEST,
+    "Cannot restore a trashed item if it's parent is also trashed, please restore the "
+    "parent first.",
+)
+
+ERROR_PARENT_ID_MUST_BE_PROVIDED = (
+    "ERROR_PARENT_ID_MUST_BE_PROVIDED",
+    HTTP_400_BAD_REQUEST,
+    "A parent id must be provided when using this trashable item type.",
+)
+
+ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED = (
+    "ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED",
+    HTTP_400_BAD_REQUEST,
+    "A parent id must NOT be provided when using this trashable item type.",
+)

backend/src/baserow/api/trash/serializers.py

@@ -0,0 +1,64 @@
+from django.utils.functional import lazy
+from drf_spectacular.types import OpenApiTypes
+from drf_spectacular.utils import extend_schema_field
+from rest_framework import serializers, fields
+
+from baserow.api.mixins import UnknownFieldRaisesExceptionSerializerMixin
+from baserow.core.models import TrashEntry, Application
+from baserow.core.trash.registries import trash_item_type_registry
+
+
+class TrashEntryRequestSerializer(
+    UnknownFieldRaisesExceptionSerializerMixin, serializers.Serializer
+):
+    trash_item_id = serializers.IntegerField(min_value=0)
+    parent_trash_item_id = serializers.IntegerField(
+        min_value=0, required=False, allow_null=True
+    )
+    trash_item_type = fields.ChoiceField(
+        choices=lazy(trash_item_type_registry.get_types, list)(),
+    )
+
+
+class TrashStructureApplicationSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = Application
+        fields = ("id", "name", "trashed")
+
+
+class TrashStructureGroupSerializer(serializers.Serializer):
+    id = serializers.IntegerField(min_value=0)
+    trashed = serializers.BooleanField()
+    name = serializers.CharField()
+    applications = TrashStructureApplicationSerializer(many=True)
+
+
+class TrashStructureSerializer(serializers.Serializer):
+    groups = TrashStructureGroupSerializer(many=True)
+
+
+class TrashContentsSerializer(serializers.ModelSerializer):
+    user_who_trashed = serializers.SerializerMethodField()
+
+    @extend_schema_field(OpenApiTypes.STR)
+    def get_user_who_trashed(self, instance):
+        if instance.user_who_trashed is not None:
+            return instance.user_who_trashed.first_name
+        else:
+            return None
+
+    class Meta:
+        model = TrashEntry
+        fields = (
+            "id",
+            "user_who_trashed",
+            "trash_item_type",
+            "trash_item_id",
+            "parent_trash_item_id",
+            "trashed_at",
+            "application",
+            "group",
+            "name",
+            "parent_name",
+            "extra_description",
+        )

backend/src/baserow/api/trash/urls.py

@@ -0,0 +1,19 @@
+from django.conf.urls import url
+
+from .views import TrashContentsView, TrashStructureView, TrashItemView
+
+app_name = "baserow.api.trash"
+
+urlpatterns = [
+    url(r"^$", TrashStructureView.as_view(), name="list"),
+    url(
+        r"^group/(?P<group_id>[0-9]+)/$",
+        TrashContentsView.as_view(),
+        name="contents",
+    ),
+    url(
+        r"^restore/$",
+        TrashItemView.as_view(),
+        name="restore",
+    ),
+]

backend/src/baserow/api/trash/views.py

@@ -0,0 +1,227 @@
+from django.conf import settings
+from drf_spectacular.types import OpenApiTypes
+from drf_spectacular.utils import extend_schema, OpenApiParameter
+from rest_framework.permissions import IsAuthenticated
+from rest_framework.response import Response
+from rest_framework.views import APIView
+
+from baserow.api.applications.errors import (
+    ERROR_APPLICATION_DOES_NOT_EXIST,
+    ERROR_APPLICATION_NOT_IN_GROUP,
+)
+from baserow.api.decorators import map_exceptions, validate_body
+from baserow.api.errors import (
+    ERROR_GROUP_DOES_NOT_EXIST,
+    ERROR_USER_NOT_IN_GROUP,
+)
+from baserow.api.pagination import PageNumberPagination
+from baserow.api.schemas import get_error_schema
+from baserow.api.serializers import get_example_pagination_serializer_class
+from baserow.core.exceptions import (
+    UserNotInGroup,
+    ApplicationNotInGroup,
+    GroupDoesNotExist,
+    ApplicationDoesNotExist,
+    TrashItemDoesNotExist,
+)
+from baserow.core.trash.handler import TrashHandler
+from .errors import (
+    ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD,
+    ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED,
+    ERROR_PARENT_ID_MUST_BE_PROVIDED,
+    ERROR_TRASH_ITEM_DOES_NOT_EXIST,
+)
+from .serializers import (
+    TrashContentsSerializer,
+    TrashStructureSerializer,
+    TrashEntryRequestSerializer,
+)
+from ...core.trash.exceptions import (
+    CannotRestoreChildBeforeParent,
+    ParentIdMustNotBeProvidedException,
+    ParentIdMustBeProvidedException,
+)
+
+
+class TrashItemView(APIView):
+    permission_classes = (IsAuthenticated,)
+
+    @extend_schema(
+        tags=["Trash"],
+        operation_id="restore",
+        description="Restores the specified trashed item back into baserow.",
+        request=TrashEntryRequestSerializer,
+        responses={
+            204: None,
+            400: get_error_schema(
+                [
+                    "ERROR_USER_NOT_IN_GROUP",
+                    "ERROR_TRASH_ITEM_DOES_NOT_EXIST",
+                    "ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD",
+                    "ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED",
+                    "ERROR_PARENT_ID_MUST_BE_PROVIDED",
+                ]
+            ),
+        },
+    )
+    @validate_body(TrashEntryRequestSerializer)
+    @map_exceptions(
+        {
+            UserNotInGroup: ERROR_USER_NOT_IN_GROUP,
+            TrashItemDoesNotExist: ERROR_TRASH_ITEM_DOES_NOT_EXIST,
+            CannotRestoreChildBeforeParent: ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD,
+            ParentIdMustNotBeProvidedException: ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED,
+            ParentIdMustBeProvidedException: ERROR_PARENT_ID_MUST_BE_PROVIDED,
+        }
+    )
+    def patch(self, request, data):
+        """
+        Restores the specified trashable item if it is in the trash and the user is
+        in the items group.
+        """
+
+        TrashHandler.restore_item(
+            request.user,
+            data["trash_item_type"],
+            data["trash_item_id"],
+            parent_trash_item_id=data.get("parent_trash_item_id", None),
+        )
+        return Response(status=204)
+
+
+class TrashContentsView(APIView):
+    permission_classes = (IsAuthenticated,)
+
+    @extend_schema(
+        parameters=[
+            OpenApiParameter(
+                name="group_id",
+                location=OpenApiParameter.PATH,
+                type=OpenApiTypes.INT,
+                description="Returns the trash for the group with this id.",
+            ),
+            OpenApiParameter(
+                name="application_id",
+                location=OpenApiParameter.QUERY,
+                type=OpenApiTypes.INT,
+                description="Optionally filters down the trash to only items for "
+                "this application in the group.",
+            ),
+            OpenApiParameter(
+                name="page",
+                location=OpenApiParameter.QUERY,
+                type=OpenApiTypes.INT,
+                description="Selects which page of trash contents should be returned.",
+            ),
+        ],
+        tags=["Trash"],
+        operation_id="get_contents",
+        description="Responds with trash contents for a group optionally "
+        "filtered to a specific application.",
+        responses={
+            200: get_example_pagination_serializer_class(TrashContentsSerializer),
+            400: get_error_schema(
+                [
+                    "ERROR_USER_NOT_IN_GROUP",
+                    "ERROR_APPLICATION_NOT_IN_GROUP",
+                    "ERROR_GROUP_DOES_NOT_EXIST",
+                    "ERROR_APPLICATION_DOES_NOT_EXIST",
+                ]
+            ),
+        },
+    )
+    @map_exceptions(
+        {
+            UserNotInGroup: ERROR_USER_NOT_IN_GROUP,
+            ApplicationNotInGroup: ERROR_APPLICATION_NOT_IN_GROUP,
+            GroupDoesNotExist: ERROR_GROUP_DOES_NOT_EXIST,
+            ApplicationDoesNotExist: ERROR_APPLICATION_DOES_NOT_EXIST,
+        }
+    )
+    def get(self, request, group_id):
+        """
+        Responds with any trashed items in the group or application, including an
+        entry for the group/app if they themselves are trashed.
+        """
+
+        application_id = request.GET.get("application_id", None)
+        trash_contents = TrashHandler.get_trash_contents(
+            request.user, group_id, application_id
+        )
+        paginator = PageNumberPagination(limit_page_size=settings.TRASH_PAGE_SIZE_LIMIT)
+        page = paginator.paginate_queryset(trash_contents, request, self)
+        serializer = TrashContentsSerializer(page, many=True)
+
+        return paginator.get_paginated_response(serializer.data)
+
+    @extend_schema(
+        parameters=[
+            OpenApiParameter(
+                name="group_id",
+                location=OpenApiParameter.PATH,
+                type=OpenApiTypes.INT,
+                description="The group whose trash contents to empty, including the "
+                "group itself if it is also trashed.",
+            ),
+            OpenApiParameter(
+                name="application_id",
+                location=OpenApiParameter.QUERY,
+                type=OpenApiTypes.INT,
+                description="Optionally filters down the trash to delete to only items "
+                "for this application in the group.",
+            ),
+        ],
+        tags=["Trash"],
+        operation_id="empty_contents",
+        description="Empties the specified group and/or application of trash, including"
+        " the group and application themselves if they are trashed also.",
+        responses={
+            204: None,
+            400: get_error_schema(
+                [
+                    "ERROR_USER_NOT_IN_GROUP",
+                    "ERROR_APPLICATION_NOT_IN_GROUP",
+                    "ERROR_GROUP_DOES_NOT_EXIST",
+                    "ERROR_APPLICATION_DOES_NOT_EXIST",
+                ]
+            ),
+        },
+    )
+    @map_exceptions(
+        {
+            UserNotInGroup: ERROR_USER_NOT_IN_GROUP,
+            ApplicationNotInGroup: ERROR_APPLICATION_NOT_IN_GROUP,
+            GroupDoesNotExist: ERROR_GROUP_DOES_NOT_EXIST,
+            ApplicationDoesNotExist: ERROR_APPLICATION_DOES_NOT_EXIST,
+        }
+    )
+    def delete(self, request, group_id):
+        """
+        Empties the group and/or application of trash permanently deleting any trashed
+        contents, including the group and application if they are also trashed.
+        """
+
+        application_id = request.GET.get("application_id", None)
+        TrashHandler.empty(request.user, group_id, application_id)
+        return Response(status=204)
+
+
+class TrashStructureView(APIView):
+    permission_classes = (IsAuthenticated,)
+
+    @extend_schema(
+        tags=["Trash"],
+        operation_id="get_trash_structure",
+        description="Responds with the groups and applications available for the "
+        "requesting user to inspect the trash contents of.",
+        responses={
+            200: TrashStructureSerializer,
+        },
+    )
+    def get(self, request):
+        """
+        Responds with the structure of the trash for the user.
+        """
+
+        structure = TrashHandler.get_trash_structure(request.user)
+        return Response(TrashStructureSerializer(structure).data)

backend/src/baserow/api/urls.py

@@ -10,6 +10,7 @@ from .user_files import urls as user_files_urls
 from .groups import urls as group_urls
 from .templates import urls as templates_urls
 from .applications import urls as application_urls
+from .trash import urls as trash_urls
 
 
 app_name = "baserow.api"
@@ -28,6 +29,7 @@ urlpatterns = (
         path("groups/", include(group_urls, namespace="groups")),
         path("templates/", include(templates_urls, namespace="templates")),
         path("applications/", include(application_urls, namespace="applications")),
+        path("trash/", include(trash_urls, namespace="trash")),
     ]
     + application_type_registry.api_urls
     + plugin_registry.api_urls

backend/src/baserow/config/settings/base.py

@@ -82,6 +82,10 @@ CELERY_BROKER_URL = REDIS_URL
 CELERY_TASK_ROUTES = {
     "baserow.contrib.database.export.tasks.run_export_job": {"queue": "export"},
     "baserow.contrib.database.export.tasks.clean_up_old_jobs": {"queue": "export"},
+    "baserow.core.trash.tasks.mark_old_trash_for_permanent_deletion": {
+        "queue": "export"
+    },
+    "baserow.core.trash.tasks.permanently_delete_marked_trash": {"queue": "export"},
 }
 CELERY_SOFT_TIME_LIMIT = 60 * 5
 CELERY_TIME_LIMIT = CELERY_SOFT_TIME_LIMIT + 60
@@ -221,6 +225,7 @@ SPECTACULAR_SETTINGS = {
         {"name": "Groups"},
         {"name": "Group invitations"},
         {"name": "Templates"},
+        {"name": "Trash"},
         {"name": "Applications"},
         {"name": "Database tables"},
         {"name": "Database table fields"},
@@ -260,7 +265,8 @@ if PRIVATE_BACKEND_HOSTNAME:
 
 FROM_EMAIL = os.getenv("FROM_EMAIL", "no-reply@localhost")
 RESET_PASSWORD_TOKEN_MAX_AGE = 60 * 60 * 48  # 48 hours
-ROW_PAGE_SIZE_LIMIT = 200  # Indicates how many rows can be requested at once.
+ROW_PAGE_SIZE_LIMIT = 200  # How many rows can be requested at once.
+TRASH_PAGE_SIZE_LIMIT = 200  # How many trash entries can be requested at once.
 
 # The amount of rows that can be imported when creating a table.
 INITIAL_TABLE_DATA_LIMIT = None
@@ -309,3 +315,10 @@ APPLICATION_TEMPLATES_DIR = os.path.join(BASE_DIR, "../../../templates")
 DEFAULT_APPLICATION_TEMPLATE = "project-management"
 
 MAX_FIELD_LIMIT = 1500
+
+# If you change this default please also update the default for the web-frontend found
+# in web-frontend/modules/core/module.js:55
+HOURS_UNTIL_TRASH_PERMANENTLY_DELETED = os.getenv(
+    "HOURS_UNTIL_TRASH_PERMANENTLY_DELETED", 24 * 3
+)
+OLD_TRASH_CLEANUP_CHECK_INTERVAL_MINUTES = 5

backend/src/baserow/contrib/database/api/rows/errors.py

@@ -1,6 +1,5 @@
 from rest_framework.status import HTTP_404_NOT_FOUND
 
-
 ERROR_ROW_DOES_NOT_EXIST = (
     "ERROR_ROW_DOES_NOT_EXIST",
     HTTP_404_NOT_FOUND,

backend/src/baserow/contrib/database/api/rows/views.py

@@ -1,4 +1,5 @@
 from django.conf import settings
+from django.core.exceptions import ValidationError
 from django.db import transaction
 from drf_spectacular.openapi import OpenApiParameter, OpenApiTypes
 from drf_spectacular.utils import extend_schema
@@ -8,6 +9,7 @@ from rest_framework.views import APIView
 
 from baserow.api.decorators import map_exceptions
 from baserow.api.errors import ERROR_USER_NOT_IN_GROUP
+from baserow.api.exceptions import RequestBodyValidationException
 from baserow.api.pagination import PageNumberPagination
 from baserow.api.schemas import get_error_schema
 from baserow.api.user_files.errors import ERROR_USER_FILE_DOES_NOT_EXIST
@@ -315,7 +317,13 @@ class RowsView(APIView):
             else None
         )
 
-        row = RowHandler().create_row(request.user, table, data, model, before=before)
+        try:
+            row = RowHandler().create_row(
+                request.user, table, data, model, before=before
+            )
+        except ValidationError as e:
+            raise RequestBodyValidationException(detail=e.message)
+
         serializer_class = get_row_serializer_class(
             model, RowSerializer, is_response=True
         )
@@ -458,7 +466,10 @@ class RowView(APIView):
         validation_serializer = get_row_serializer_class(model, field_ids=field_ids)
         data = validate_data(validation_serializer, request.data)
 
-        row = RowHandler().update_row(request.user, table, row_id, data, model)
+        try:
+            row = RowHandler().update_row(request.user, table, row_id, data, model)
+        except ValidationError as e:
+            raise RequestBodyValidationException(detail=e.message)
 
         serializer_class = get_row_serializer_class(
             model, RowSerializer, is_response=True

backend/src/baserow/contrib/database/application_types.py

@@ -1,15 +1,14 @@
-from django.core.management.color import no_style
-from django.urls import path, include
-from django.db import connections
 from django.conf import settings
+from django.core.management.color import no_style
+from django.db import connections
+from django.urls import path, include
 
-from baserow.core.registries import ApplicationType
 from baserow.contrib.database.fields.registries import field_type_registry
 from baserow.contrib.database.views.registries import view_type_registry
-
-from .models import Database, Table
-from .table.handler import TableHandler
+from baserow.core.registries import ApplicationType
 from .api.serializers import DatabaseSerializer
+from .models import Database, Table
+from baserow.core.trash.handler import TrashHandler
 
 
 class DatabaseApplicationType(ApplicationType):
@@ -23,11 +22,14 @@ class DatabaseApplicationType(ApplicationType):
         handler.
         """
 
-        database_tables = database.table_set.all().select_related("database__group")
-        table_handler = TableHandler()
+        database_tables = (
+            database.table_set(manager="objects_and_trash")
+            .all()
+            .select_related("database__group")
+        )
 
         for table in database_tables:
-            table_handler._delete_table(table)
+            TrashHandler.permanently_delete(table)
 
     def get_api_urls(self):
         from .api import urls as api_urls

backend/src/baserow/contrib/database/config.py

@@ -1,6 +1,10 @@
 from django.apps import AppConfig
 
-from baserow.core.registries import plugin_registry, application_type_registry
+from baserow.core.registries import (
+    plugin_registry,
+    application_type_registry,
+)
+from baserow.core.trash.registries import trash_item_type_registry
 from baserow.ws.registries import page_registry
 
 
@@ -141,6 +145,16 @@ class DatabaseConfig(AppConfig):
 
         table_exporter_registry.register(CsvTableExporter())
 
+        from .trash.trash_types import (
+            TableTrashableItemType,
+            RowTrashableItemType,
+            FieldTrashableItemType,
+        )
+
+        trash_item_type_registry.register(TableTrashableItemType())
+        trash_item_type_registry.register(FieldTrashableItemType())
+        trash_item_type_registry.register(RowTrashableItemType())
+
         # The signals must always be imported last because they use the registries
         # which need to be filled first.
         import baserow.contrib.database.ws.signals  # noqa: F403, F401

backend/src/baserow/contrib/database/fields/field_types.py

@@ -2,6 +2,7 @@ from collections import defaultdict
 from datetime import datetime, date
 from decimal import Decimal
 from random import randrange, randint
+from typing import Any, Callable, Dict, List
 
 from dateutil import parser
 from dateutil.parser import ParserError
@@ -497,8 +498,47 @@ class LinkRowFieldType(FieldType):
         )
 
     def get_export_value(self, value, field_object):
-        instance = field_object["field"]
+        def map_to_export_value(inner_value, inner_field_object):
+            return inner_field_object["type"].get_export_value(
+                inner_value, inner_field_object
+            )
 
+        return self._get_and_map_pk_values(field_object, value, map_to_export_value)
+
+    def get_human_readable_value(self, value, field_object):
+        def map_to_human_readable_value(inner_value, inner_field_object):
+            return inner_field_object["type"].get_human_readable_value(
+                inner_value, inner_field_object
+            )
+
+        return ",".join(
+            self._get_and_map_pk_values(
+                field_object, value, map_to_human_readable_value
+            )
+        )
+
+    def _get_and_map_pk_values(
+        self, field_object, value, map_func: Callable[[Any, Dict[str, Any]], Any]
+    ):
+        """
+        Helper function which given a linked row field pointing at another model,
+        constructs a list of the related row's primary key values which are mapped by
+        the provided map_func function.
+
+        For example, Table A has Field 1 which links to Table B. Table B has a text
+        primary key column. This function takes the value for a single row of of
+        Field 1, which is a number of related rows in Table B. It then gets
+        the primary key column values for those related rows in Table B and applies
+        map_func to each individual value. Finally it returns those mapped values as a
+        list.
+
+        :param value: The value of the link field in a specific row.
+        :param field_object: The field object for the link field.
+        :param map_func: A function to apply to each linked primary key value.
+        :return: A list of mapped linked primary key values.
+        """
+
+        instance = field_object["field"]
         if hasattr(instance, "_related_model"):
             related_model = instance._related_model
             primary_field = next(
@@ -508,28 +548,27 @@ class LinkRowFieldType(FieldType):
             )
             if primary_field:
                 primary_field_name = primary_field["name"]
-                primary_field_type = primary_field["type"]
                 primary_field_values = []
                 for sub in value.all():
                     # Ensure we also convert the value from the other table to it's
-                    # export form as it could be an odd field type!
+                    # appropriate form as it could be an odd field type!
                     linked_value = getattr(sub, primary_field_name)
                     if self._is_unnamed_primary_field_value(linked_value):
-                        export_linked_value = f"unnamed row {sub.id}"
+                        linked_pk_value = f"unnamed row {sub.id}"
                     else:
-                        export_linked_value = primary_field_type.get_export_value(
+                        linked_pk_value = map_func(
                             getattr(sub, primary_field_name), primary_field
                         )
-                    primary_field_values.append(export_linked_value)
+                    primary_field_values.append(linked_pk_value)
                 return primary_field_values
         return []
 
     @staticmethod
     def _is_unnamed_primary_field_value(primary_field_value):
         """
-        Checks if the value for a linked primary field is considered "empty".
+        Checks if the value for a linked primary field is considered "unnamed".
         :param primary_field_value: The value of a primary field row in a linked table.
-        :return: If this value is considered an empty primary field value.
+        :return: If this value is considered an unnamed primary field value.
         """
 
         if isinstance(primary_field_value, list):
@@ -780,7 +819,7 @@ class LinkRowFieldType(FieldType):
             )
             to_field.save()
 
-    def after_delete(self, field, model, user, connection):
+    def after_delete(self, field, model, connection):
         """
         After the field has been deleted we also need to delete the related field.
         """
@@ -883,6 +922,9 @@ class LinkRowFieldType(FieldType):
     ):
         getattr(row, field_name).set(value)
 
+    def get_related_items_to_trash(self, field) -> List[Any]:
+        return [field.link_row_related_field]
+
 
 class EmailFieldType(FieldType):
     type = "email"
@@ -1004,6 +1046,15 @@ class FileFieldType(FieldType):
 
         return files
 
+    def get_human_readable_value(self, value, field_object):
+        file_names = []
+        for file in value:
+            file_names.append(
+                file["visible_name"],
+            )
+
+        return ",".join(file_names)
+
     def get_response_serializer_field(self, instance, **kwargs):
         return FileFieldResponseSerializer(many=True, required=False, **kwargs)
 
@@ -1015,7 +1066,7 @@ class FileFieldType(FieldType):
         )
 
     def get_model_field(self, instance, **kwargs):
-        return JSONField(default=[], **kwargs)
+        return JSONField(default=list, **kwargs)
 
     def random_value(self, instance, fake, cache):
         """

backend/src/baserow/contrib/database/fields/handler.py

@@ -7,6 +7,7 @@ from django.db.utils import ProgrammingError, DataError
 
 from baserow.contrib.database.db.schema import lenient_schema_editor
 from baserow.contrib.database.views.handler import ViewHandler
+from baserow.core.trash.handler import TrashHandler
 from baserow.core.utils import extract_allowed, set_allowed_attrs
 from .exceptions import (
     PrimaryFieldAlreadyExists,
@@ -56,6 +57,9 @@ class FieldHandler:
         except Field.DoesNotExist:
             raise FieldDoesNotExist(f"The field with id {field_id} does not exist.")
 
+        if TrashHandler.item_has_a_trashed_parent(field.table, check_item_also=True):
+            raise FieldDoesNotExist(f"The field with id {field_id} does not exist.")
+
         return field
 
     def create_field(
@@ -326,22 +330,8 @@ class FieldHandler:
             )
 
         field = field.specific
-        field_type = field_type_registry.get_by_model(field)
-
-        # Remove the field from the table schema.
-        connection = connections[settings.USER_TABLE_DATABASE]
-        with connection.schema_editor() as schema_editor:
-            from_model = field.table.get_model(field_ids=[], fields=[field])
-            model_field = from_model._meta.get_field(field.db_column)
-            schema_editor.remove_field(from_model, model_field)
-
+        TrashHandler.trash(user, group, field.table.database, field)
         field_id = field.id
-        field.delete()
-
-        # After the field is deleted we are going to to call the after_delete method of
-        # the field type because some instance cleanup might need to happen.
-        field_type.after_delete(field, from_model, user, connection)
-
         field_deleted.send(self, field_id=field_id, field=field, user=user)
 
     def update_field_select_options(self, user, field, select_options):

backend/src/baserow/contrib/database/fields/models.py

@@ -1,12 +1,14 @@
-from django.db import models
 from django.contrib.contenttypes.models import ContentType
+from django.db import models
 
-from baserow.core.utils import to_snake_case, remove_special_characters
+from baserow.contrib.database.mixins import ParentFieldTrashableModelMixin
 from baserow.core.mixins import (
     OrderableMixin,
     PolymorphicContentTypeMixin,
     CreatedAndUpdatedOnMixin,
+    TrashableModelMixin,
 )
+from baserow.core.utils import to_snake_case, remove_special_characters
 
 NUMBER_TYPE_INTEGER = "INTEGER"
 NUMBER_TYPE_DECIMAL = "DECIMAL"
@@ -42,7 +44,11 @@ def get_default_field_content_type():
 
 
 class Field(
-    CreatedAndUpdatedOnMixin, OrderableMixin, PolymorphicContentTypeMixin, models.Model
+    TrashableModelMixin,
+    CreatedAndUpdatedOnMixin,
+    OrderableMixin,
+    PolymorphicContentTypeMixin,
+    models.Model,
 ):
     """
     Because each field type can have custom settings, for example precision for a number
@@ -98,7 +104,7 @@ class Field(
         return name
 
 
-class SelectOption(models.Model):
+class SelectOption(ParentFieldTrashableModelMixin, models.Model):
     value = models.CharField(max_length=255, blank=True)
     color = models.CharField(max_length=255, blank=True)
     order = models.PositiveIntegerField()
@@ -279,7 +285,7 @@ class LinkRowField(Field):
     @staticmethod
     def get_new_relation_id():
         last_id = (
-            LinkRowField.objects.all().aggregate(
+            LinkRowField.objects_and_trash.all().aggregate(
                 largest=models.Max("link_row_relation_id")
             )["largest"]
             or 0

backend/src/baserow/contrib/database/fields/registries.py

@@ -1,3 +1,5 @@
+from typing import Any, List
+
 from django.db.models import Q
 
 from baserow.core.registry import (
@@ -411,7 +413,7 @@ class FieldType(
         :type before: any
         """
 
-    def after_delete(self, field, model, user, connection):
+    def after_delete(self, field, model, connection):
         """
         This hook is called right after the field has been deleted and the schema
         change has been done.
@@ -420,8 +422,6 @@ class FieldType(
         :type field: Field
         :param model: The Django model that contains the deleted field.
         :type model: Model
-        :param user: The user on whose behalf the delete is done.
-        :type user: User
         :param connection: The connection used to make the database schema change.
         :type connection: DatabaseWrapper
         """
@@ -616,6 +616,43 @@ class FieldType(
 
         return value
 
+    def get_human_readable_value(self, value: Any, field_object) -> str:
+        """
+        Should convert the value of the provided field to a human readable string for
+        display purposes.
+
+        :param value: The value of the field extracted from a row to convert to human
+            readable form.
+        :param field_object: The field object for the field to extract
+        :type field_object: FieldObject
+        :return A human readable string.
+        """
+
+        human_readable_value = self.get_export_value(value, field_object)
+        if human_readable_value is None:
+            return ""
+        else:
+            return str(human_readable_value)
+
+    # noinspection PyMethodMayBeStatic
+    def get_related_items_to_trash(self, field) -> List[Any]:
+        """
+        When a field of this type is trashed/restored, or the table it is in
+        trashed/restored, this method should return any other trashable items that
+        should be trashed or restored in tandem.
+
+        For example, a link field has an opposing link field in the other table that
+        should also be trashed when it is trashed. And so for link fields this method
+        is overridden to return the related field so it is trashed/restored correctly.
+
+        :param field: The specific instance of the field that is being trashed or whose
+            table is being trashed.
+        :return: A list of related trashable items that should be trashed or restored
+            in tandem with this field or it's table.
+        """
+
+        return []
+
 
 class FieldTypeRegistry(
     APIUrlsRegistryMixin, CustomFieldsRegistryMixin, ModelRegistryMixin, Registry

backend/src/baserow/contrib/database/fields/signals.py

@@ -2,5 +2,6 @@ from django.dispatch import Signal
 
 
 field_created = Signal()
+field_restored = Signal()
 field_updated = Signal()
 field_deleted = Signal()

backend/src/baserow/contrib/database/management/commands/fill_table.py

@@ -34,9 +34,7 @@ class Command(BaseCommand):
     def handle(self, *args, **options):
         table_id = options["table_id"]
         limit = options["limit"]
-        fake = Faker()
-        row_handler = RowHandler()
-        cache = {}
+        add_columns = "add_columns" in options and options["add_columns"]
 
         try:
             table = Table.objects.get(pk=table_id)
@@ -46,52 +44,52 @@ class Command(BaseCommand):
             )
             sys.exit(1)
 
-        if "add_columns" in options and options["add_columns"]:
-            self.create_a_column_for_every_type(table)
-
-        model = table.get_model()
-
-        # Find out what the highest order is because we want to append the new rows.
-        order = ceil(
-            model.objects.aggregate(max=Max("order")).get("max") or Decimal("0")
-        )
-
-        for i in range(0, limit):
-            # Based on the random_value function we have for each type we can
-            # build a dict with a random value for each field.
-            values = {
-                f"field_{field_id}": field_object["type"].random_value(
-                    field_object["field"], fake, cache
-                )
-                for field_id, field_object in model._field_objects.items()
-            }
-
-            values, manytomany_values = row_handler.extract_manytomany_values(
-                values, model
-            )
-            order += Decimal("1")
-            values["order"] = order
-
-            # Insert the row with the randomly created values.
-            instance = model.objects.create(**values)
-
-            # Changes the set of the manytomany values.
-            for field_name, value in manytomany_values.items():
-                if value and len(value) > 0:
-                    getattr(instance, field_name).set(value)
+        fill_table(limit, table, add_columns=add_columns)
 
         self.stdout.write(self.style.SUCCESS(f"{limit} rows have been inserted."))
 
-    @staticmethod
-    def create_a_column_for_every_type(table):
-        field_handler = FieldHandler()
-        all_kwargs_per_type = construct_all_possible_field_kwargs(None, None, None)
-        for field_type_name, all_possible_kwargs in all_kwargs_per_type.items():
-            if field_type_name == "link_row":
-                continue
-            i = 0
-            for kwargs in all_possible_kwargs:
-                i = i + 1
-                field_handler.create_field(
-                    table.database.group.users.first(), table, field_type_name, **kwargs
-                )
+
+def fill_table(limit, table, add_columns=False):
+    fake = Faker()
+    row_handler = RowHandler()
+    cache = {}
+    if add_columns:
+        create_a_column_for_every_type(table)
+    model = table.get_model()
+    # Find out what the highest order is because we want to append the new rows.
+    order = ceil(model.objects.aggregate(max=Max("order")).get("max") or Decimal("0"))
+    for i in range(0, limit):
+        # Based on the random_value function we have for each type we can
+        # build a dict with a random value for each field.
+        values = {
+            f"field_{field_id}": field_object["type"].random_value(
+                field_object["field"], fake, cache
+            )
+            for field_id, field_object in model._field_objects.items()
+        }
+
+        values, manytomany_values = row_handler.extract_manytomany_values(values, model)
+        order += Decimal("1")
+        values["order"] = order
+
+        # Insert the row with the randomly created values.
+        instance = model.objects.create(**values)
+
+        # Changes the set of the manytomany values.
+        for field_name, value in manytomany_values.items():
+            if value and len(value) > 0:
+                getattr(instance, field_name).set(value)
+
+
+def create_a_column_for_every_type(table):
+    field_handler = FieldHandler()
+    all_kwargs_per_type = construct_all_possible_field_kwargs(None, None, None)
+    for field_type_name, all_possible_kwargs in all_kwargs_per_type.items():
+        if field_type_name == "link_row":
+            continue
+        i = 0
+        for kwargs in all_possible_kwargs:
+            i = i + 1
+            field_handler.create_field(
+                table.database.group.users.first(), table, field_type_name, **kwargs
+            )

backend/src/baserow/contrib/database/migrations/0032_trash.py

@@ -0,0 +1,66 @@
+# Generated by Django 2.2.11 on 2021-06-14 09:08
+from django.conf import settings
+from django.db import migrations, models, connections
+
+
+def forward(apps, schema_editor):
+    # noinspection PyPep8Naming
+    Table = apps.get_model("database", "Table")
+
+    connection = connections[settings.USER_TABLE_DATABASE]
+    with connection.schema_editor() as tables_schema_editor:
+        # We need to stop the transaction because we might need to lock a lot of tables
+        # which could result in an out of memory exception.
+        tables_schema_editor.atomic.__exit__(None, None, None)
+
+        for table in Table.objects.all():
+            table_name = f"database_table_{table.id}"
+            # Make the forward migration more idempotent / resilient to partially
+            # applied migrations due to the lack of a transaction by using IF NOT
+            # EXISTS.
+            tables_schema_editor.execute(
+                f"ALTER TABLE {table_name} "
+                f"ADD COLUMN IF NOT EXISTS trashed boolean not null default false"
+            )
+
+
+def reverse(apps, schema_editor):
+    # noinspection PyPep8Naming
+    Table = apps.get_model("database", "Table")
+
+    connection = connections[settings.USER_TABLE_DATABASE]
+    with connection.schema_editor() as tables_schema_editor:
+        # We need to stop the transaction because we might need to lock a lot of tables
+        # which could result in an out of memory exception.
+        tables_schema_editor.atomic.__exit__(None, None, None)
+
+        # apps.get_model doesn't return a model using our custom overridden managers
+        # so we can safely use .objects which will return all trashed tables also
+        for table in Table.objects.all():
+            table_name = f"database_table_{table.id}"
+            # Make the reverse migration more idempotent / resilient to partially
+            # applied migrations due to the lack of a transaction by using IF EXISTS.
+            tables_schema_editor.execute(
+                f"ALTER TABLE {table_name} DROP COLUMN IF EXISTS trashed"
+            )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("database", "0031_fix_url_field_max_length"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="field",
+            name="trashed",
+            field=models.BooleanField(default=False),
+        ),
+        migrations.AddField(
+            model_name="table",
+            name="trashed",
+            field=models.BooleanField(default=False),
+        ),
+        migrations.RunPython(forward, reverse),
+    ]

backend/src/baserow/contrib/database/mixins.py

@@ -0,0 +1,4 @@
+from baserow.core.mixins import make_trashable_mixin
+
+ParentFieldTrashableModelMixin = make_trashable_mixin("field")
+ParentTableTrashableModelMixin = make_trashable_mixin("table")

backend/src/baserow/contrib/database/rows/handler.py

@@ -8,6 +8,7 @@ from django.db.models.fields.related import ManyToManyField
 from django.conf import settings
 
 from baserow.contrib.database.fields.models import Field
+from baserow.core.trash.handler import TrashHandler
 
 from .exceptions import RowDoesNotExist
 from .signals import (
@@ -126,7 +127,7 @@ class RowHandler:
 
         :param values: The values where to extract the manytomany values from.
         :type values: dict
-        :param model: The model containing the fields. They key, which is also the
+        :param model: The model containing the fields. The key, which is also the
             field name, is used to check in the model if the value is a ManyToMany
             value.
         :type model: Model
@@ -405,7 +406,8 @@ class RowHandler:
         )
 
         row_id = row.id
-        row.delete()
+
+        TrashHandler.trash(user, group, table.database, row, parent_id=table.id)
 
         row_deleted.send(
             self,

backend/src/baserow/contrib/database/table/handler.py

@@ -1,6 +1,7 @@
 from django.db import connections
 from django.conf import settings
 
+from baserow.core.trash.handler import TrashHandler
 from baserow.core.utils import extract_allowed, set_allowed_attrs
 from baserow.contrib.database.fields.models import TextField
 from baserow.contrib.database.views.handler import ViewHandler
@@ -45,6 +46,9 @@ class TableHandler:
         except Table.DoesNotExist:
             raise TableDoesNotExist(f"The table with id {table_id} does not exist.")
 
+        if TrashHandler.item_has_a_trashed_parent(table):
+            raise TableDoesNotExist(f"The table with id {table_id} does not exist.")
+
         return table
 
     def create_table(
@@ -304,16 +308,6 @@ class TableHandler:
         table.database.group.has_user(user, raise_error=True)
         table_id = table.id
 
-        self._delete_table(table)
+        TrashHandler.trash(user, table.database.group, table.database, table)
 
         table_deleted.send(self, table_id=table_id, table=table, user=user)
-
-    def _delete_table(self, table):
-        """Deletes the table schema and instance."""
-
-        connection = connections[settings.USER_TABLE_DATABASE]
-        with connection.schema_editor() as schema_editor:
-            model = table.get_model()
-            schema_editor.delete_model(model)
-
-        table.delete()

backend/src/baserow/contrib/database/table/models.py

@@ -17,7 +17,11 @@ from baserow.contrib.database.fields.field_filters import (
 from baserow.contrib.database.fields.registries import field_type_registry
 from baserow.contrib.database.views.exceptions import ViewFilterTypeNotAllowedForField
 from baserow.contrib.database.views.registries import view_filter_type_registry
-from baserow.core.mixins import OrderableMixin, CreatedAndUpdatedOnMixin
+from baserow.core.mixins import (
+    OrderableMixin,
+    CreatedAndUpdatedOnMixin,
+    TrashableModelMixin,
+)
 
 deconstruct_filter_key_regex = re.compile(r"filter__field_([0-9]+)__([a-zA-Z0-9_]*)$")
 
@@ -184,13 +188,24 @@ class TableModelQuerySet(models.QuerySet):
 
 class TableModelManager(models.Manager):
     def get_queryset(self):
-        return TableModelQuerySet(self.model, using=self._db)
+        return TableModelQuerySet(self.model, using=self._db).filter(trashed=False)
 
 
 FieldObject = Dict[str, Any]
 
 
-class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
+class GeneratedTableModel:
+    """
+    This class is purely used to mark Model classes which have been generated by Baserow
+    for identification using instance(possible_baserow_model, GeneratedTableModel).
+    """
+
+    pass
+
+
+class Table(
+    TrashableModelMixin, CreatedAndUpdatedOnMixin, OrderableMixin, models.Model
+):
     database = models.ForeignKey("database.Database", on_delete=models.CASCADE)
     order = models.PositiveIntegerField()
     name = models.CharField(max_length=255)
@@ -203,6 +218,9 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
         queryset = Table.objects.filter(database=database)
         return cls.get_highest_order_of_queryset(queryset) + 1
 
+    def get_database_table_name(self):
+        return f"database_table_{self.id}"
+
     def get_model(
         self, fields=None, field_ids=None, attribute_names=False, manytomany_models=None
     ):
@@ -241,7 +259,7 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
             (),
             {
                 "managed": False,
-                "db_table": f"database_table_{self.id}",
+                "db_table": self.get_database_table_name(),
                 "app_label": app_label,
                 "ordering": ["order", "id"],
             },
@@ -269,8 +287,13 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
             ),
         }
 
-        # Construct a query to fetch all the fields of that table.
-        fields_query = self.field_set.all()
+        # Construct a query to fetch all the fields of that table. We need to include
+        # any trashed fields so the created model still has them present as the column
+        # is still actually there. If the model did not have the trashed field
+        # attributes then model.objects.create will fail as the trashed columns will
+        # be given null values by django triggering not null constraints in the
+        # database.
+        fields_query = self.field_set(manager="objects_and_trash").all()
 
         # If the field ids are provided we must only fetch the fields of which the ids
         # are in that list.
@@ -291,13 +314,17 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
         # We will have to add each field to with the correct field name and model field
         # to the attribute list in order for the model to work.
         for field in fields:
+            trashed = field.trashed
             field = field.specific
             field_type = field_type_registry.get_by_model(field)
             field_name = field.db_column
             # If attribute_names is True we will not use 'field_{id}' as attribute name,
             # but we will rather use a name the user provided.
+
             if attribute_names:
                 field_name = field.model_attribute_name
+                if trashed:
+                    field_name = f"trashed_{field_name}"
                 # If the field name already exists we will append '_field_{id}' to each
                 # entry that is a duplicate.
                 if field_name in attrs:
@@ -307,13 +334,15 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
                 if field_name in duplicate_field_names:
                     field_name = f"{field_name}_{field.db_column}"
 
-            # Add the generated objects and information to the dict that optionally can
-            # be returned.
-            attrs["_field_objects"][field.id] = {
-                "field": field,
-                "type": field_type,
-                "name": field_name,
-            }
+            if not trashed:
+                # Add the generated objects and information to the dict that
+                # optionally can be returned. We exclude trashed fields here so they
+                # are not displayed by baserow anywhere.
+                attrs["_field_objects"][field.id] = {
+                    "field": field,
+                    "type": field_type,
+                    "name": field_name,
+                }
 
             # Add the field to the attribute dict that is used to generate the model.
             # All the kwargs that are passed to the `get_model_field` method are going
@@ -326,6 +355,8 @@ class Table(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
         model = type(
             str(f"Table{self.pk}Model"),
             (
+                GeneratedTableModel,
+                TrashableModelMixin,
                 CreatedAndUpdatedOnMixin,
                 models.Model,
             ),

backend/src/baserow/contrib/database/tokens/models.py

@@ -1,13 +1,14 @@
 from django.db import models
 from django.contrib.auth import get_user_model
 
+from baserow.core.mixins import ParentGroupTrashableModelMixin
 from baserow.core.models import Group
 
 
 User = get_user_model()
 
 
-class Token(models.Model):
+class Token(ParentGroupTrashableModelMixin, models.Model):
     """
     A token can be used to authenticate a user with the row create, read, update and
     delete endpoints.

backend/src/baserow/contrib/database/trash/trash_types.py

@@ -0,0 +1,220 @@
+from typing import Optional, Any, List
+
+from django.conf import settings
+from django.db import connections
+
+from baserow.contrib.database.fields.models import Field
+from baserow.contrib.database.fields.registries import field_type_registry
+from baserow.contrib.database.fields.signals import field_restored
+from baserow.contrib.database.rows.signals import row_created
+from baserow.contrib.database.table.models import Table, GeneratedTableModel
+from baserow.contrib.database.table.signals import table_created
+from baserow.core.exceptions import TrashItemDoesNotExist
+from baserow.core.models import Application, TrashEntry
+from baserow.core.trash.registries import TrashableItemType
+
+
+class TableTrashableItemType(TrashableItemType):
+
+    type = "table"
+    model_class = Table
+
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        return trashed_item.database
+
+    def get_name(self, trashed_item: Table) -> str:
+        return trashed_item.name
+
+    def trashed_item_restored(self, trashed_item: Table, trash_entry: TrashEntry):
+        table_created.send(
+            self,
+            table=trashed_item,
+            user=None,
+        )
+
+    def permanently_delete_item(self, trashed_item: Table):
+        """Deletes the table schema and instance."""
+
+        connection = connections[settings.USER_TABLE_DATABASE]
+        # We are using a different connection, and hence any outer transactions
+        # calling this method using a different connection will not roll back
+        # changes made to the USER_TABLE_DATABASE. Hence it is possible that the
+        # table has already been deleted if this code previously ran, but then the
+        # wrapping transaction failed causing the trashed_item to be restored.
+        # So we check to see if the table still exists before attempting to
+        # delete it to avoid a ProgrammingError being thrown by the schema_editor.
+        with connection.cursor() as cursor:
+            cursor.execute(
+                """SELECT EXISTS (
+SELECT FROM information_schema.tables
+WHERE  table_schema = 'public'
+AND    table_name   = %s
+);""",
+                [trashed_item.get_database_table_name()],
+            )
+            table_exists = cursor.fetchone()[0]
+            if table_exists:
+                with connection.schema_editor() as schema_editor:
+                    model = trashed_item.get_model()
+                    schema_editor.delete_model(model)
+
+        trashed_item.delete()
+
+    # noinspection PyMethodMayBeStatic
+    def get_items_to_trash(self, trashed_item: Table) -> List[Any]:
+        """
+        When trashing a link row field we also want to trash the related link row field.
+        """
+
+        model = trashed_item.get_model()
+        things_to_trash = [trashed_item]
+        for field in model._field_objects.values():
+            things_to_trash += field["type"].get_related_items_to_trash(field["field"])
+        return things_to_trash
+
+
+class FieldTrashableItemType(TrashableItemType):
+
+    type = "field"
+    model_class = Field
+
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        return trashed_item.table
+
+    def get_name(self, trashed_item: Field) -> str:
+        return trashed_item.name
+
+    def trashed_item_restored(self, trashed_item: Field, trash_entry: TrashEntry):
+        field_restored.send(
+            self,
+            field=trashed_item,
+            user=None,
+        )
+
+    def permanently_delete_item(self, field: Application):
+        """Deletes the table schema and instance."""
+
+        field = field.specific
+        field_type = field_type_registry.get_by_model(field)
+
+        # Remove the field from the table schema.
+        connection = connections[settings.USER_TABLE_DATABASE]
+        with connection.schema_editor() as schema_editor:
+            from_model = field.table.get_model(field_ids=[], fields=[field])
+            model_field = from_model._meta.get_field(field.db_column)
+            schema_editor.remove_field(from_model, model_field)
+
+        field.delete()
+
+        # After the field is deleted we are going to to call the after_delete method of
+        # the field type because some instance cleanup might need to happen.
+        field_type.after_delete(field, from_model, connection)
+
+    # noinspection PyMethodMayBeStatic
+    def get_items_to_trash(self, trashed_item: Field) -> List[Any]:
+        """
+        When trashing a link row field we also want to trash the related link row field.
+        """
+
+        items_to_trash = [trashed_item]
+        field_type = field_type_registry.get_by_model(trashed_item.specific)
+        return items_to_trash + field_type.get_related_items_to_trash(
+            trashed_item.specific
+        )
+
+
+class RowTrashableItemType(TrashableItemType):
+
+    type = "row"
+    model_class = GeneratedTableModel
+
+    @property
+    def requires_parent_id(self) -> bool:
+        # A row is not unique just with its ID. We also need the table id (parent id)
+        # to uniquely identify and lookup a specific row.
+        return True
+
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        return self._get_table(parent_id)
+
+    @staticmethod
+    def _get_table(parent_id):
+        try:
+            return Table.objects_and_trash.get(id=parent_id)
+        except Table.DoesNotExist:
+            # The parent table must have been actually deleted, in which case the
+            # row itself no longer exits.
+            raise TrashItemDoesNotExist()
+
+    def get_name(self, trashed_item) -> str:
+        return str(trashed_item.id)
+
+    def trashed_item_restored(self, trashed_item, trash_entry: TrashEntry):
+        table = self.get_parent(trashed_item, trash_entry.parent_trash_item_id)
+
+        model = table.get_model()
+        row_created.send(
+            self,
+            row=trashed_item,
+            table=table,
+            model=model,
+            before=None,
+            user=None,
+        )
+
+    def permanently_delete_item(self, row):
+        row.delete()
+
+    def lookup_trashed_item(
+        self, trashed_entry: TrashEntry, trash_item_lookup_cache=None
+    ):
+        """
+        Returns the actual instance of the trashed item. By default simply does a get
+        on the model_class's trash manager.
+
+        :param trash_item_lookup_cache: A cache dict used to store the generated models
+            for a given table so if looking up many rows from the same table we only
+            need to lookup the tables fields etc once.
+        :param trashed_entry: The entry to get the real trashed instance for.
+        :return: An instance of the model_class with trashed_item_id
+        """
+
+        # Cache the expensive table.get_model function call if we are looking up
+        # many trash items at once.
+        if trash_item_lookup_cache is not None:
+            model_cache = trash_item_lookup_cache.setdefault(
+                "row_table_model_cache", {}
+            )
+            try:
+                model = model_cache[trashed_entry.parent_trash_item_id]
+            except KeyError:
+                model = model_cache.setdefault(
+                    trashed_entry.parent_trash_item_id,
+                    self._get_table_model(trashed_entry.parent_trash_item_id),
+                )
+        else:
+            model = self._get_table_model(trashed_entry.parent_trash_item_id)
+
+        try:
+            return model.trash.get(id=trashed_entry.trash_item_id)
+        except model.DoesNotExist:
+            raise TrashItemDoesNotExist()
+
+    def _get_table_model(self, table_id):
+        table = self._get_table(table_id)
+        return table.get_model()
+
+    # noinspection PyMethodMayBeStatic
+    def get_extra_description(self, trashed_item: Any, table) -> Optional[str]:
+
+        model = table.get_model()
+        for field in model._field_objects.values():
+            if field["field"].primary:
+                primary_value = field["type"].get_human_readable_value(
+                    getattr(trashed_item, field["name"]), field
+                )
+                if primary_value is None or primary_value == "":
+                    primary_value = f"unnamed row {trashed_item.id}"
+                return primary_value
+
+        return "unknown row"

backend/src/baserow/contrib/database/views/handler.py

@@ -4,6 +4,7 @@ from baserow.contrib.database.fields.exceptions import FieldNotInTable
 from baserow.contrib.database.fields.field_filters import FilterBuilder
 from baserow.contrib.database.fields.models import Field
 from baserow.contrib.database.fields.registries import field_type_registry
+from baserow.core.trash.handler import TrashHandler
 from baserow.core.utils import extract_allowed, set_allowed_attrs
 from .exceptions import (
     ViewDoesNotExist,
@@ -68,6 +69,9 @@ class ViewHandler:
         except View.DoesNotExist:
             raise ViewDoesNotExist(f"The view with id {view_id} does not exist.")
 
+        if TrashHandler.item_has_a_trashed_parent(view.table, check_item_also=True):
+            raise ViewDoesNotExist(f"The view with id {view_id} does not exist.")
+
         return view
 
     def create_view(self, user, table, type_name, **kwargs):
@@ -331,6 +335,13 @@ class ViewHandler:
                 f"The view filter with id {view_filter_id} does not exist."
             )
 
+        if TrashHandler.item_has_a_trashed_parent(
+            view_filter.view.table, check_item_also=True
+        ):
+            raise ViewFilterDoesNotExist(
+                f"The view filter with id {view_filter_id} does not exist."
+            )
+
         group = view_filter.view.table.database.group
         group.has_user(user, raise_error=True)
 
@@ -559,6 +570,13 @@ class ViewHandler:
                 f"The view sort with id {view_sort_id} does not exist."
             )
 
+        if TrashHandler.item_has_a_trashed_parent(
+            view_sort.view.table, check_item_also=True
+        ):
+            raise ViewSortDoesNotExist(
+                f"The view sort with id {view_sort_id} does not exist."
+            )
+
         group = view_sort.view.table.database.group
         group.has_user(user, raise_error=True)
 

backend/src/baserow/contrib/database/views/models.py

@@ -6,6 +6,10 @@ from baserow.contrib.database.fields.field_filters import (
     FILTER_TYPE_OR,
 )
 from baserow.contrib.database.fields.models import Field
+from baserow.contrib.database.mixins import (
+    ParentTableTrashableModelMixin,
+    ParentFieldTrashableModelMixin,
+)
 from baserow.core.mixins import (
     OrderableMixin,
     PolymorphicContentTypeMixin,
@@ -24,7 +28,11 @@ def get_default_view_content_type():
 
 
 class View(
-    CreatedAndUpdatedOnMixin, OrderableMixin, PolymorphicContentTypeMixin, models.Model
+    ParentTableTrashableModelMixin,
+    CreatedAndUpdatedOnMixin,
+    OrderableMixin,
+    PolymorphicContentTypeMixin,
+    models.Model,
 ):
     table = models.ForeignKey("database.Table", on_delete=models.CASCADE)
     order = models.PositiveIntegerField()
@@ -57,7 +65,7 @@ class View(
         return cls.get_highest_order_of_queryset(queryset) + 1
 
 
-class ViewFilter(models.Model):
+class ViewFilter(ParentFieldTrashableModelMixin, models.Model):
     view = models.ForeignKey(
         View,
         on_delete=models.CASCADE,
@@ -85,7 +93,7 @@ class ViewFilter(models.Model):
         ordering = ("id",)
 
 
-class ViewSort(models.Model):
+class ViewSort(ParentFieldTrashableModelMixin, models.Model):
     view = models.ForeignKey(
         View,
         on_delete=models.CASCADE,
@@ -149,7 +157,7 @@ class GridView(View):
         return field_options
 
 
-class GridViewFieldOptions(models.Model):
+class GridViewFieldOptions(ParentFieldTrashableModelMixin, models.Model):
     grid_view = models.ForeignKey(GridView, on_delete=models.CASCADE)
     field = models.ForeignKey(Field, on_delete=models.CASCADE)
     # The defaults should be the same as in the `fieldCreated` of the `GridViewType`

backend/src/baserow/contrib/database/ws/fields/signals.py

@@ -25,6 +25,23 @@ def field_created(sender, field, user, **kwargs):
     )
 
 
+@receiver(field_signals.field_restored)
+def field_restored(sender, field, user, **kwargs):
+    table_page_type = page_registry.get("table")
+    transaction.on_commit(
+        lambda: table_page_type.broadcast(
+            {
+                "type": "field_restored",
+                "field": field_type_registry.get_serializer(
+                    field, FieldSerializer
+                ).data,
+            },
+            getattr(user, "web_socket_id", None),
+            table_id=field.table_id,
+        )
+    )
+
+
 @receiver(field_signals.field_updated)
 def field_updated(sender, field, user, **kwargs):
     table_page_type = page_registry.get("table")

backend/src/baserow/core/config.py

@@ -3,3 +3,11 @@ from django.apps import AppConfig
 
 class CoreConfig(AppConfig):
     name = "baserow.core"
+
+    def ready(self):
+        from baserow.core.trash.registries import trash_item_type_registry
+        from baserow.core.trash.trash_types import GroupTrashableItemType
+        from baserow.core.trash.trash_types import ApplicationTrashableItemType
+
+        trash_item_type_registry.register(GroupTrashableItemType())
+        trash_item_type_registry.register(ApplicationTrashableItemType())

backend/src/baserow/core/exceptions.py

@@ -117,3 +117,9 @@ class TemplateFileDoesNotExist(Exception):
     Raised when the JSON template file does not exist in the
     APPLICATION_TEMPLATE_DIRS directory.
     """
+
+
+class TrashItemDoesNotExist(Exception):
+    """
+    Raised when the trash item does not exist in the database.
+    """

backend/src/baserow/core/handler.py

@@ -38,6 +38,7 @@ from .exceptions import (
     TemplateFileDoesNotExist,
     TemplateDoesNotExist,
 )
+from .trash.handler import TrashHandler
 from .utils import extract_allowed, set_allowed_attrs
 from .registries import application_type_registry
 from .signals import (
@@ -174,7 +175,8 @@ class CoreHandler:
     def delete_group(self, user, group):
         """
         Deletes an existing group and related applications if the user has admin
-        permissions to the group.
+        permissions for the group. The group can be restored after deletion using the
+        trash handler.
 
         :param user: The user on whose behalf the delete is done.
         :type: user: User
@@ -193,23 +195,12 @@ class CoreHandler:
         group_id = group.id
         group_users = list(group.users.all())
 
-        self._delete_group(group)
+        TrashHandler.trash(user, group, None, group)
 
         group_deleted.send(
             self, group_id=group_id, group=group, group_users=group_users, user=user
         )
 
-    def _delete_group(self, group):
-        """Deletes the provided group."""
-
-        # Select all the applications so we can delete them via the handler which is
-        # needed in order to call the pre_delete method for each application.
-        applications = group.application_set.all().select_related("group")
-        for application in applications:
-            self._delete_application(application)
-
-        group.delete()
-
     def order_groups(self, user, group_ids):
         """
         Changes the order of groups for a user.
@@ -594,6 +585,11 @@ class CoreHandler:
                 f"The application with id {application_id} does not exist."
             )
 
+        if TrashHandler.item_has_a_trashed_parent(application):
+            raise ApplicationDoesNotExist(
+                f"The application with id {application_id} does not exist."
+            )
+
         return application
 
     def create_application(self, user, group, type_name, **kwargs):
@@ -625,9 +621,7 @@ class CoreHandler:
             group=group, order=last_order, **application_values
         )
 
-        application_created.send(
-            self, application=instance, user=user, type_name=type_name
-        )
+        application_created.send(self, application=instance, user=user)
 
         return instance
 
@@ -703,21 +697,12 @@ class CoreHandler:
         application.group.has_user(user, raise_error=True)
 
         application_id = application.id
-        application = self._delete_application(application)
+        TrashHandler.trash(user, application.group, application, application)
 
         application_deleted.send(
             self, application_id=application_id, application=application, user=user
         )
 
-    def _delete_application(self, application):
-        """Deletes an application and the related relations in the correct way."""
-
-        application = application.specific
-        application_type = application_type_registry.get_by_model(application)
-        application_type.pre_delete(application)
-        application.delete()
-        return application
-
     def export_group_applications(self, group, files_buffer, storage=None):
         """
         Exports the applications of a group to a list. They can later be imported via
@@ -871,7 +856,7 @@ class CoreHandler:
                 and installed_template.group
                 and installed_template.export_hash != export_hash
             ):
-                self._delete_group(installed_template.group)
+                TrashHandler.permanently_delete(installed_template.group)
 
             # If the installed template does not yet exist or if there is a export
             # hash mismatch, which means the group has already been deleted, we can
@@ -944,7 +929,7 @@ class CoreHandler:
             for template_file_path in templates
         ]
         for template in Template.objects.filter(~Q(slug__in=slugs)):
-            self._delete_group(template.group)
+            TrashHandler.permanently_delete(template.group)
             template.delete()
 
         # Delete all the categories that don't have any templates anymore.

backend/src/baserow/core/managers.py

@@ -1,6 +1,36 @@
 from django.db import models
 
 
-class GroupQuerySet(models.QuerySet):
-    def of_user(self, user):
-        return self.filter(users__exact=user).order_by("groupuser__order")
+def make_trash_manager(trashed, parent=None):
+    """
+    Constructs a Django Queryset Manager which filters down it's base queryset according
+    to the provided parameters.
+
+    We need to use a method to construct a closed class rather than say, __init__
+    parameters given to a single base class as Django will init a models managers
+    without providing any kwargs breaking things horribly. This way django can init
+    the manager without providing any kwargs and it will still filter correctly.
+
+    :param trashed: If true the manager will only return trashed entries, if false then
+        only returns non-trashed entries.
+    :param parent: If specified will use the trashed column in a related model where
+        parent is the name of the FK to the related model.
+    :return: A manager with an override get_queryset filtered accordingly.
+    """
+
+    filter_kwargs = {}
+
+    if parent is None:
+        filter_kwargs["trashed"] = trashed
+    else:
+        filter_kwargs[f"{parent}__trashed"] = trashed
+
+    class Manager(models.Manager):
+        def get_queryset(self):
+            return super().get_queryset().filter(**filter_kwargs)
+
+    return Manager
+
+
+TrashOnlyManager = make_trash_manager(trashed=True)
+NoTrashManager = make_trash_manager(trashed=False)

backend/src/baserow/core/migrations/0008_trash.py

@@ -0,0 +1,87 @@
+# Generated by Django 2.2.11 on 2021-06-16 09:23
+
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ("core", "0007_userlogentry"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="application",
+            name="trashed",
+            field=models.BooleanField(default=False),
+        ),
+        migrations.AddField(
+            model_name="group",
+            name="trashed",
+            field=models.BooleanField(default=False),
+        ),
+        migrations.CreateModel(
+            name="TrashEntry",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("trash_item_type", models.TextField()),
+                (
+                    "parent_trash_item_id",
+                    models.PositiveIntegerField(blank=True, null=True),
+                ),
+                ("trash_item_id", models.PositiveIntegerField()),
+                ("should_be_permanently_deleted", models.BooleanField(default=False)),
+                ("trashed_at", models.DateTimeField(auto_now_add=True)),
+                ("name", models.TextField()),
+                ("parent_name", models.TextField(blank=True, null=True)),
+                ("extra_description", models.TextField(blank=True, null=True)),
+                (
+                    "application",
+                    models.ForeignKey(
+                        blank=True,
+                        null=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="core.Application",
+                    ),
+                ),
+                (
+                    "group",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE, to="core.Group"
+                    ),
+                ),
+                (
+                    "user_who_trashed",
+                    models.ForeignKey(
+                        blank=True,
+                        null=True,
+                        on_delete=django.db.models.deletion.SET_NULL,
+                        to=settings.AUTH_USER_MODEL,
+                    ),
+                ),
+            ],
+        ),
+        migrations.AddIndex(
+            model_name="trashentry",
+            index=models.Index(
+                fields=["-trashed_at", "trash_item_type", "group", "application"],
+                name="core_trashe_trashed_0bf61a_idx",
+            ),
+        ),
+        migrations.AlterUniqueTogether(
+            name="trashentry",
+            unique_together={
+                ("trash_item_type", "parent_trash_item_id", "trash_item_id")
+            },
+        ),
+    ]

backend/src/baserow/core/mixins.py

@@ -1,9 +1,15 @@
-from django.db import models
-from django.db.models import Case, When, Value
-from django.db.models.fields import NOT_PROVIDED
 from django.contrib.contenttypes.models import ContentType
+from django.db import models
+from django.db.models import Case, When, Value, Manager
+from django.db.models.fields import NOT_PROVIDED
 from django.utils.functional import cached_property
 
+from baserow.core.managers import (
+    make_trash_manager,
+    NoTrashManager,
+    TrashOnlyManager,
+)
+
 
 class OrderableMixin:
     """
@@ -162,3 +168,46 @@ class CreatedAndUpdatedOnMixin(models.Model):
 
     class Meta:
         abstract = True
+
+
+def make_trashable_mixin(parent):
+    """
+    Constructs a mixin class which overrides a models managers to ensure trashed entries
+    are not available via objects, but instead via the new trash manager.
+
+    :param parent: If specified will use the trashed column in a related model where
+        parent is the name of the FK to the related model.
+    :return: A mixin with overridden managers which correctly filter out trashed rows.
+    """
+
+    no_trash_manager = make_trash_manager(trashed=False, parent=parent)
+    trash_only_manager = make_trash_manager(trashed=True, parent=parent)
+
+    class TrashableMixin(models.Model):
+        objects = no_trash_manager()
+        trash = trash_only_manager()
+        objects_and_trash = Manager()
+
+        class Meta:
+            abstract = True
+
+    return TrashableMixin
+
+
+ParentGroupTrashableModelMixin = make_trashable_mixin("group")
+
+
+class TrashableModelMixin(models.Model):
+    """
+    This mixin allows this model to be trashed and restored from the trash by adding
+    new columns recording it's trash status.
+    """
+
+    trashed = models.BooleanField(default=False)
+
+    objects = NoTrashManager()
+    trash = TrashOnlyManager()
+    objects_and_trash = Manager()
+
+    class Meta:
+        abstract = True

backend/src/baserow/core/models.py

@@ -6,16 +6,28 @@ from rest_framework.exceptions import NotAuthenticated
 
 from baserow.core.user_files.models import UserFile
 
-from .managers import GroupQuerySet
 from .mixins import (
     OrderableMixin,
     PolymorphicContentTypeMixin,
     CreatedAndUpdatedOnMixin,
+    TrashableModelMixin,
+    ParentGroupTrashableModelMixin,
 )
 from .exceptions import UserNotInGroup, UserInvalidGroupPermissionsError
 
 
-__all__ = ["UserFile"]
+__all__ = [
+    "Settings",
+    "Group",
+    "GroupUser",
+    "GroupInvitation",
+    "Application",
+    "TemplateCategory",
+    "Template",
+    "UserLogEntry",
+    "TrashEntry",
+    "UserFile",
+]
 
 
 User = get_user_model()
@@ -48,17 +60,26 @@ class Settings(models.Model):
     )
 
 
-class Group(CreatedAndUpdatedOnMixin, models.Model):
+class Group(TrashableModelMixin, CreatedAndUpdatedOnMixin):
     name = models.CharField(max_length=100)
     users = models.ManyToManyField(User, through="GroupUser")
 
-    objects = GroupQuerySet.as_manager()
+    def application_set_including_trash(self):
+        """
+        :return: The applications for this group including any trashed applications.
+        """
+        return self.application_set(manager="objects_and_trash")
 
     def has_template(self):
         return self.template_set.all().exists()
 
     def has_user(
-        self, user, permissions=None, raise_error=False, allow_if_template=False
+        self,
+        user,
+        permissions=None,
+        raise_error=False,
+        allow_if_template=False,
+        include_trash=False,
     ):
         """
         Checks if the provided user belongs to the group.
@@ -74,6 +95,9 @@ class Group(CreatedAndUpdatedOnMixin, models.Model):
         :param allow_if_template: If true and if the group is related to a template,
             then True is always returned and no exception will be raised.
         :type allow_if_template: bool
+        :param include_trash: If true then also checks if the group has been trashed
+            instead of raising a DoesNotExist exception.
+        :type include_trash: bool
         :raises UserNotInGroup: If the user does not belong to the group.
         :raises UserInvalidGroupPermissionsError: If the user does belong to the group,
             but doesn't have the right permissions.
@@ -92,7 +116,12 @@ class Group(CreatedAndUpdatedOnMixin, models.Model):
             else:
                 return False
 
-        queryset = GroupUser.objects.filter(user_id=user.id, group_id=self.id)
+        if include_trash:
+            manager = GroupUser.objects_and_trash
+        else:
+            manager = GroupUser.objects
+
+        queryset = manager.filter(user_id=user.id, group_id=self.id)
 
         if raise_error:
             try:
@@ -112,7 +141,12 @@ class Group(CreatedAndUpdatedOnMixin, models.Model):
         return f"<Group id={self.id}, name={self.name}>"
 
 
-class GroupUser(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
+class GroupUser(
+    ParentGroupTrashableModelMixin,
+    CreatedAndUpdatedOnMixin,
+    OrderableMixin,
+    models.Model,
+):
     user = models.ForeignKey(
         User,
         on_delete=models.CASCADE,
@@ -143,7 +177,9 @@ class GroupUser(CreatedAndUpdatedOnMixin, OrderableMixin, models.Model):
         return cls.get_highest_order_of_queryset(queryset) + 1
 
 
-class GroupInvitation(CreatedAndUpdatedOnMixin, models.Model):
+class GroupInvitation(
+    ParentGroupTrashableModelMixin, CreatedAndUpdatedOnMixin, models.Model
+):
     group = models.ForeignKey(
         Group,
         on_delete=models.CASCADE,
@@ -178,7 +214,11 @@ class GroupInvitation(CreatedAndUpdatedOnMixin, models.Model):
 
 
 class Application(
-    CreatedAndUpdatedOnMixin, OrderableMixin, PolymorphicContentTypeMixin, models.Model
+    TrashableModelMixin,
+    CreatedAndUpdatedOnMixin,
+    OrderableMixin,
+    PolymorphicContentTypeMixin,
+    models.Model,
 ):
     group = models.ForeignKey(Group, on_delete=models.CASCADE)
     name = models.CharField(max_length=50)
@@ -250,3 +290,63 @@ class UserLogEntry(models.Model):
     class Meta:
         get_latest_by = "timestamp"
         ordering = ["-timestamp"]
+
+
+class TrashEntry(models.Model):
+    """
+    A TrashEntry is a record indicating that another model in Baserow has a trashed
+    row. When a user deletes certain things in Baserow they are not actually deleted
+    from the database, but instead marked as trashed. Trashed rows can be restored
+    or permanently deleted.
+
+    The other model must mixin the TrashableModelMixin and also have a corresponding
+    TrashableItemType registered specifying exactly how to delete and restore that
+    model.
+    """
+
+    # The TrashableItemType.type of the item that is trashed.
+    trash_item_type = models.TextField()
+    # We need to also store the parent id as for some trashable items the
+    # trash_item_type and the trash_item_id is not unique as the items of that type
+    # could be spread over multiple tables with the same id.
+    parent_trash_item_id = models.PositiveIntegerField(null=True, blank=True)
+    # The actual id of the item that is trashed
+    trash_item_id = models.PositiveIntegerField()
+
+    # If the user who trashed something gets deleted we still wish to preserve this
+    # trash record as it is independent of if the user exists or not.
+    user_who_trashed = models.ForeignKey(
+        User, on_delete=models.SET_NULL, null=True, blank=True
+    )
+
+    # The group and application fields are used to group trash into separate "bins"
+    # which can be viewed and emptied independently of each other.
+
+    # The group the item that is trashed is found in, if the trashed item is the
+    # group itself then this should also be set to that trashed group.
+    group = models.ForeignKey(Group, on_delete=models.CASCADE)
+    # The application the item that is trashed is found in, if the trashed item is the
+    # application itself then this should also be set to that trashed application.
+    application = models.ForeignKey(
+        Application, on_delete=models.CASCADE, null=True, blank=True
+    )
+
+    # When set to true this trash entry will be picked up by a periodic job and the
+    # underlying item will be actually permanently deleted along with the entry.
+    should_be_permanently_deleted = models.BooleanField(default=False)
+    trashed_at = models.DateTimeField(auto_now_add=True)
+
+    # The name, name of the parent and any extra description are cached so lookups
+    # of trashed items are simple and do not require joining to many different tables
+    # to simply get these details.
+    name = models.TextField()
+    parent_name = models.TextField(null=True, blank=True)
+    extra_description = models.TextField(null=True, blank=True)
+
+    class Meta:
+        unique_together = ("trash_item_type", "parent_trash_item_id", "trash_item_id")
+        indexes = [
+            models.Index(
+                fields=["-trashed_at", "trash_item_type", "group", "application"]
+            )
+        ]

backend/src/baserow/core/signals.py

@@ -4,6 +4,7 @@ from django.dispatch import Signal
 group_created = Signal()
 group_updated = Signal()
 group_deleted = Signal()
+group_restored = Signal()
 
 group_user_updated = Signal()
 group_user_deleted = Signal()

backend/src/baserow/core/tasks.py

@@ -0,0 +1,11 @@
+from .trash.tasks import (
+    permanently_delete_marked_trash,
+    mark_old_trash_for_permanent_deletion,
+    setup_period_trash_tasks,
+)
+
+__all__ = [
+    "permanently_delete_marked_trash",
+    "mark_old_trash_for_permanent_deletion",
+    "setup_period_trash_tasks",
+]

backend/src/baserow/core/trash/exceptions.py

@@ -0,0 +1,18 @@
+class CannotRestoreChildBeforeParent(Exception):
+    """
+    Raised when attempting to restore a trashed item when it's parent is also trashed.
+    """
+
+
+class ParentIdMustBeProvidedException(Exception):
+    """
+    Raised when attempting to access or restore a trashed item without providing it's
+    parent's id.
+    """
+
+
+class ParentIdMustNotBeProvidedException(Exception):
+    """
+    Raised when attempting to access or restore a trashed item which should not have
+    it's parent id provided, but it was anyway.
+    """

backend/src/baserow/core/trash/handler.py

@@ -0,0 +1,418 @@
+from typing import Optional, Dict, Any
+
+from django.conf import settings
+from django.contrib.auth import get_user_model
+from django.db import transaction
+from django.db.models import QuerySet
+from django.utils import timezone
+
+from baserow.core.exceptions import (
+    ApplicationNotInGroup,
+    GroupDoesNotExist,
+    ApplicationDoesNotExist,
+    TrashItemDoesNotExist,
+)
+from baserow.core.models import TrashEntry, Application, Group
+from baserow.core.trash.exceptions import (
+    CannotRestoreChildBeforeParent,
+    ParentIdMustBeProvidedException,
+    ParentIdMustNotBeProvidedException,
+)
+from baserow.core.trash.registries import TrashableItemType, trash_item_type_registry
+
+User = get_user_model()
+
+
+class TrashHandler:
+    @staticmethod
+    def trash(
+        requesting_user: User,
+        group: Group,
+        application: Optional[Application],
+        trash_item,
+        parent_id=None,
+    ) -> TrashEntry:
+        """
+        Marks the provided trashable item as trashed meaning it will no longer be
+        visible or usable in Baserow. However any user with access to its group can
+        restore the item after it is trashed to make it visible and usable again. After
+        a configurable timeout period or when the a user explicitly empties the
+        trash trashed items will be permanently deleted.
+
+        :param parent_id: The id of the parent object if known
+        :param requesting_user: The user who is requesting that this item be trashed.
+        :param group: The group the trashed item is in.
+        :param application: If the item is in an application the application.
+        :param trash_item: The item to be trashed.
+        :return: A newly created entry in the TrashEntry table for this item.
+        """
+
+        # Check if the parent has a trash entry, if so link this new entry to it
+        # via a cascading on delete FK to ensure if the parent entry is deleted then
+        # this one is also deleted. We do this as say if a table is perm deleted,
+        # we don't then want to
+        with transaction.atomic():
+            trash_item_type = trash_item_type_registry.get_by_model(trash_item)
+
+            _check_parent_id_valid(parent_id, trash_item_type)
+
+            items_to_trash = trash_item_type.get_items_to_trash(trash_item)
+            for item in items_to_trash:
+                item.trashed = True
+                item.save()
+
+            parent = trash_item_type.get_parent(trash_item, parent_id)
+            if parent is not None:
+                parent_type = trash_item_type_registry.get_by_model(parent)
+                parent_name = parent_type.get_name(parent)
+            else:
+                parent_name = None
+
+            return TrashEntry.objects.create(
+                user_who_trashed=requesting_user,
+                group=group,
+                application=application,
+                trash_item_type=trash_item_type.type,
+                trash_item_id=trash_item.id,
+                name=trash_item_type.get_name(trash_item),
+                parent_name=parent_name,
+                parent_trash_item_id=parent_id,
+                # If we ever introduce the ability to trash many rows at once this
+                # call will generate a model per row currently, instead a model cache
+                # should be added so generated models can be shared.
+                extra_description=trash_item_type.get_extra_description(
+                    trash_item, parent
+                ),
+            )
+
+    @staticmethod
+    def restore_item(user, trash_item_type, trash_item_id, parent_trash_item_id=None):
+        """
+        Restores an item from the trash re-instating it back in Baserow exactly how it
+        was before it was trashed.
+        :param user: The user requesting to restore trashed item.
+        :param trash_item_type: The trashable item type of the item to restore.
+        :param parent_trash_item_id: The parent id of the item to restore.
+        :param trash_item_id: The trash item id of the item to restore.
+        :raises CannotRestoreChildBeforeParent: Raised if the item being restored has
+            any parent, or parent of a parent etc which is trashed as that item should
+            be restored first.
+        """
+
+        with transaction.atomic():
+            trashable_item_type = trash_item_type_registry.get(trash_item_type)
+            _check_parent_id_valid(parent_trash_item_id, trashable_item_type)
+
+            trash_entry = _get_trash_entry(
+                user, trash_item_type, parent_trash_item_id, trash_item_id
+            )
+
+            trash_item = trashable_item_type.lookup_trashed_item(trash_entry, {})
+
+            items_to_restore = trashable_item_type.get_items_to_trash(trash_item)
+
+            if TrashHandler.item_has_a_trashed_parent(
+                trash_item,
+                parent_id=trash_entry.parent_trash_item_id,
+            ):
+                raise CannotRestoreChildBeforeParent()
+
+            trash_entry.delete()
+
+            # Restore everything in the database first before we run any restored
+            # hooks otherwise signals etc might try to be sent when dependent items are
+            # still trashed in the database.
+            for item in items_to_restore:
+                item.trashed = False
+                item.save()
+
+            for item in items_to_restore:
+                restore_type = trash_item_type_registry.get_by_model(item)
+                restore_type.trashed_item_restored(item, trash_entry)
+
+    @staticmethod
+    def get_trash_structure(user: User) -> Dict[str, Any]:
+        """
+        Returns the structure of the trash available to the user. This consists of the
+        groups and their applications the user has access to. Each group and application
+        indicates whether it itself has been trashed.
+
+        :param user: The user to return the trash structure for.
+        :return: An ordered list of groups and their applications which could possibly
+            have trash contents.
+        """
+
+        structure = {"groups": []}
+        groups = _get_groups_excluding_perm_deleted(user)
+        for group in groups:
+            applications = _get_applications_excluding_perm_deleted(group)
+            structure["groups"].append(
+                {
+                    "id": group.id,
+                    "trashed": group.trashed,
+                    "name": group.name,
+                    "applications": applications,
+                }
+            )
+
+        return structure
+
+    @staticmethod
+    def mark_old_trash_for_permanent_deletion():
+        """
+        Updates all trash entries which are older than a django setting for permanent
+        deletion. Does not perform the deletion itself.
+        """
+
+        now = timezone.now()
+        cutoff = now - timezone.timedelta(
+            hours=settings.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED
+        )
+        TrashEntry.objects.filter(trashed_at__lte=cutoff).update(
+            should_be_permanently_deleted=True
+        )
+
+    @staticmethod
+    def empty(requesting_user: User, group_id: int, application_id: Optional[int]):
+        """
+        Marks all items in the selected group (or application in the group if
+        application_id is provided) as should be permanently deleted.
+        """
+
+        with transaction.atomic():
+            trash_contents = TrashHandler.get_trash_contents(
+                requesting_user, group_id, application_id
+            )
+            trash_contents.update(should_be_permanently_deleted=True)
+
+    @staticmethod
+    def permanently_delete_marked_trash():
+        """
+        Looks up every trash item marked for permanent deletion and removes them
+        irreversibly from the database along with their corresponding trash entries.
+        """
+
+        trash_item_lookup_cache = {}
+        for trash_entry in TrashEntry.objects.filter(
+            should_be_permanently_deleted=True
+        ):
+            with transaction.atomic():
+                trash_item_type = trash_item_type_registry.get(
+                    trash_entry.trash_item_type
+                )
+
+                try:
+                    to_delete = trash_item_type.lookup_trashed_item(
+                        trash_entry, trash_item_lookup_cache
+                    )
+                    trash_item_type.permanently_delete_item(to_delete)
+                except TrashItemDoesNotExist:
+                    # When a parent item is deleted it should also delete all of it's
+                    # children. Hence we expect that many of these TrashEntries to no
+                    # longer point to an existing item. In such a situation we just want
+                    # to delete the entry as the item itself has been correctly deleted.
+                    pass
+                trash_entry.delete()
+
+    @staticmethod
+    def permanently_delete(trashable_item):
+        """
+        Actually removes the provided trashable item from the database irreversibly.
+        :param trashable_item: An instance of a TrashableItemType model_class to delete.
+        """
+
+        trash_item_type = trash_item_type_registry.get_by_model(trashable_item)
+        trash_item_type.permanently_delete_item(trashable_item)
+
+    @staticmethod
+    def get_trash_contents(
+        user: User, group_id: int, application_id: Optional[int]
+    ) -> QuerySet:
+        """
+        Looks up the trash contents for a particular group optionally filtered by
+        the provided application id.
+        :param user: The user who is requesting to see the trash contents.
+        :param group_id: The group to lookup trash contents inside of.
+        :param application_id: The optional application to filter down the trash
+            contents to only this group.
+        :raises GroupDoesNotExist: If the group_id is for an non
+            existent group.
+        :raises ApplicationDoesNotExist: If the application_id is for an non
+            existent application.
+        :raises ApplicationNotInGroup: If the application_id is for an application
+            not in the requested group.
+        :raises UserNotInGroup: If the user does not belong to the group.
+        :return: a queryset of the trash items in the group optionally filtered by
+            the provided application.
+        """
+
+        group = _get_group(group_id, user)
+
+        application = _get_application(application_id, group, user)
+
+        trash_contents = TrashEntry.objects.filter(
+            group=group, should_be_permanently_deleted=False
+        )
+        if application:
+            trash_contents = trash_contents.filter(application=application)
+        return trash_contents.order_by("-trashed_at")
+
+    @staticmethod
+    def item_has_a_trashed_parent(item, parent_id=None, check_item_also=False):
+        """
+        Given an instance of a model which is trashable (item) checks if it has a parent
+        which is trashed. Returns True if it's parent, or parent's parent (and so on)
+        is trashed, False if no parent is trashed.
+
+        :param check_item_also: If true also checks if the provided item itself is
+            trashed and returns True if so.
+        :param item: An instance of a trashable model to check.
+        :param parent_id: If the trashable type of the provided instance requires an
+            id to lookup it's parent it must be provided here.
+        :return: If the provided item has a trashed parent or not.
+        """
+
+        trash_item_type = trash_item_type_registry.get_by_model(item)
+
+        if check_item_also and item.trashed:
+            return True
+
+        while True:
+            _check_parent_id_valid(parent_id, trash_item_type)
+            parent = trash_item_type.get_parent(item, parent_id)
+            if parent is None:
+                return False
+            elif parent.trashed:
+                return True
+            else:
+                item = parent
+                # Right now only row the lowest item in the "trash hierarchy" requires
+                # a parent id. Hence we know that as we go up into parents we will
+                # no longer need parent id's to do the lookups. However if in the future
+                # there is an intermediary trashable item which also requires a
+                # parent_id this method will not work and will need to be changed.
+                parent_id = None
+                trash_item_type = trash_item_type_registry.get_by_model(item)
+
+
+def _get_group(group_id, user):
+    try:
+        group = Group.objects_and_trash.get(id=group_id)
+    except Group.DoesNotExist:
+        raise GroupDoesNotExist
+    # Check that the group is not marked for perm deletion, if so we don't want
+    # to display it's contents anymore as it should be permanently deleted soon.
+    try:
+        trash_entry = _get_trash_entry(user, "group", None, group.id)
+        if trash_entry.should_be_permanently_deleted:
+            raise GroupDoesNotExist
+    except TrashItemDoesNotExist:
+        pass
+    group.has_user(user, raise_error=True, include_trash=True)
+    return group
+
+
+def _get_application(application_id, group, user):
+    if application_id is not None:
+        try:
+            application = Application.objects_and_trash.get(id=application_id)
+        except Application.DoesNotExist:
+            raise ApplicationDoesNotExist()
+
+        try:
+            trash_entry = _get_trash_entry(user, "application", None, application.id)
+            if trash_entry.should_be_permanently_deleted:
+                raise ApplicationDoesNotExist
+        except TrashItemDoesNotExist:
+            pass
+
+        if application.group != group:
+            raise ApplicationNotInGroup()
+    else:
+        application = None
+    return application
+
+
+def _check_parent_id_valid(
+    parent_trash_item_id: Optional[int], trashable_item_type: TrashableItemType
+):
+    """
+    Raises an exception if the parent id is missing when it is required, or when the
+    parent id is included when it is not required.
+
+    Because the parent id is stored in the database and used to lookup trash entries
+    uniquely, we want to enforce it is not provided when not needed. For example, if
+    the API allowed you to provide a parent id when trashing a table, that id will then
+    be stored, and it must then be provided when trying to restore that table otherwise
+    the entry will not be found. Hence by being strict we ensure it's not possible to
+    accidentally trash an item which is hard to then restore.
+
+    :param parent_trash_item_id: The parent id
+    :param trashable_item_type: The type to check to see if it needs a parent id or not.
+    :return:
+    """
+
+    if trashable_item_type.requires_parent_id and parent_trash_item_id is None:
+        raise ParentIdMustBeProvidedException()
+    if not trashable_item_type.requires_parent_id and parent_trash_item_id is not None:
+        raise ParentIdMustNotBeProvidedException()
+
+
+def _get_groups_excluding_perm_deleted(user):
+    groups = Group.objects_and_trash.filter(groupuser__user=user)
+    perm_deleted_groups = TrashEntry.objects.filter(
+        trash_item_type="group",
+        should_be_permanently_deleted=True,
+        trash_item_id__in=groups.values_list("id", flat=True),
+    ).values_list("trash_item_id", flat=True)
+    groups = groups.exclude(id__in=perm_deleted_groups).order_by("groupuser__order")
+    return groups
+
+
+def _get_applications_excluding_perm_deleted(group):
+    perm_deleted_apps = TrashEntry.objects.filter(
+        trash_item_type="application",
+        should_be_permanently_deleted=True,
+        trash_item_id__in=group.application_set_including_trash().values_list(
+            "id", flat=True
+        ),
+    ).values_list("trash_item_id", flat=True)
+    applications = (
+        group.application_set_including_trash()
+        .exclude(id__in=perm_deleted_apps)
+        .order_by("order", "id")
+    )
+    return applications
+
+
+def _get_trash_entry(
+    requesting_user: User,
+    trash_item_type: str,
+    parent_trash_item_id: Optional[int],
+    trash_item_id: int,
+) -> TrashEntry:
+    """
+    Gets the trash entry for a particular resource in baserow which has been
+    trashed.
+    :param trash_item_id: The id of the item to look for a trash entry for.
+    :param parent_trash_item_id: The parent id of the item to look for a trash
+        entry for.
+    :param trash_item_type: The trashable type of the item.
+    :param requesting_user: The user requesting to get the trashed item ,
+        they must be in the group of the trashed item otherwise this will raise
+        UserNotInGroup if not.
+    :returns The trash entry for the specified baserow item.
+    :raises UserNotInGroup: If the requesting_user is not in the trashed items
+        group.
+    """
+
+    try:
+        trash_entry = TrashEntry.objects.get(
+            parent_trash_item_id=parent_trash_item_id,
+            trash_item_id=trash_item_id,
+            trash_item_type=trash_item_type,
+        )
+    except TrashEntry.DoesNotExist:
+        raise TrashItemDoesNotExist()
+    trash_entry.group.has_user(requesting_user, raise_error=True, include_trash=True)
+    return trash_entry

backend/src/baserow/core/trash/registries.py

@@ -0,0 +1,124 @@
+from abc import ABC, abstractmethod
+from typing import Any, Optional, List
+
+from baserow.core.exceptions import TrashItemDoesNotExist
+from baserow.core.registry import (
+    ModelRegistryMixin,
+    Registry,
+    ModelInstanceMixin,
+    Instance,
+)
+
+
+class TrashableItemType(ModelInstanceMixin, Instance, ABC):
+    """
+    A TrashableItemType specifies a baserow model which can be trashed.
+    """
+
+    def lookup_trashed_item(self, trashed_entry, trash_item_lookup_cache=None):
+        """
+        Returns the actual instance of the trashed item. By default simply does a get
+        on the model_class's trash manager.
+
+        :param trash_item_lookup_cache: A dictionary which can be used to store
+            expensive objects used to lookup this item which could be re-used when
+            looking up other items of this type.
+        :param trashed_entry: The entry to get the real trashed instance for.
+        :return: An instance of the model_class with trashed_item_id
+        """
+
+        try:
+            return self.model_class.trash.get(id=trashed_entry.trash_item_id)
+        except self.model_class.DoesNotExist:
+            raise TrashItemDoesNotExist()
+
+    @abstractmethod
+    def permanently_delete_item(self, trashed_item: Any):
+        """
+        Should be implemented to actually delete the specified trashed item from the
+        database and do any other required clean-up.
+
+        :param trashed_item: The item to delete permanently.
+        """
+
+        pass
+
+    @property
+    def requires_parent_id(self) -> bool:
+        """
+        :returns True if this trash type requires a parent id to lookup a specific item,
+            false if only the trash_item_id is required to perform a lookup.
+        """
+        return False
+
+    @abstractmethod
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        """
+        Returns the parent for this item.
+
+        :param trashed_item: The item to lookup a parent for.
+        :returns Either the parent item or None if this item has no parent.
+        """
+        pass
+
+    @abstractmethod
+    def trashed_item_restored(self, trashed_item: Any, trash_entry):
+        """
+        Called when a trashed item is restored, should perform any extra operations
+        such as sending web socket signals which occur when an item is "created" in
+        baserow.
+
+        :param trash_entry: The trash entry that was restored from.
+        :param trashed_item: The item that has been restored.
+        """
+        pass
+
+    @abstractmethod
+    def get_name(self, trashed_item: Any) -> str:
+        """
+        Should return the name of this particular trashed item to display in the trash
+        modal.
+
+        :param trashed_item: The item to be named.
+        :return The name of the trashed_group
+        """
+        pass
+
+    # noinspection PyMethodMayBeStatic
+    def get_items_to_trash(self, trashed_item: Any) -> List[Any]:
+        """
+        When trashing some items you might also need to mark other related items also
+        as trashed. Override this method and return instances of trashable models
+        which should also be marked as trashed. Each of these instances will not
+        however be given their own unique trash entry, but instead be restored
+        all together from a single trash entry made for trashed_item only.
+
+        :return  An iterable of trashable model instances.
+        """
+        return [trashed_item]
+
+    # noinspection PyMethodMayBeStatic
+    def get_extra_description(
+        self, trashed_item: Any, parent: Optional[Any]
+    ) -> Optional[str]:
+        """
+        Should return an optional extra description to show along with the trash
+        entry for this particular trashed item.
+
+        :return A short string giving extra detail on what has been trashed.
+        """
+        return None
+
+
+class TrashableItemTypeRegistry(ModelRegistryMixin, Registry):
+    """
+    The TrashableItemTypeRegistry contains models which can be "trashed" in baserow.
+    When an instance of a trashable model is trashed it is removed from baserow but
+    not permanently. Once trashed an item can then be restored to add it back to
+    baserow just as it was when it was trashed.
+    """
+
+    name = "trashable"
+
+
+trash_item_type_registry = TrashableItemTypeRegistry()

backend/src/baserow/core/trash/tasks.py

@@ -0,0 +1,36 @@
+from datetime import timedelta
+from django.conf import settings
+from baserow.config.celery import app
+
+
+# noinspection PyUnusedLocal
+@app.task(
+    bind=True,
+)
+def mark_old_trash_for_permanent_deletion(self):
+    from baserow.core.trash.handler import TrashHandler
+
+    TrashHandler.mark_old_trash_for_permanent_deletion()
+
+
+# noinspection PyUnusedLocal
+@app.task(
+    bind=True,
+)
+def permanently_delete_marked_trash(self):
+    from baserow.core.trash.handler import TrashHandler
+
+    TrashHandler.permanently_delete_marked_trash()
+
+
+# noinspection PyUnusedLocal
+@app.on_after_finalize.connect
+def setup_period_trash_tasks(sender, **kwargs):
+    sender.add_periodic_task(
+        timedelta(minutes=settings.OLD_TRASH_CLEANUP_CHECK_INTERVAL_MINUTES),
+        mark_old_trash_for_permanent_deletion.s(),
+    )
+    sender.add_periodic_task(
+        timedelta(minutes=settings.OLD_TRASH_CLEANUP_CHECK_INTERVAL_MINUTES),
+        permanently_delete_marked_trash.s(),
+    )

backend/src/baserow/core/trash/trash_types.py

@@ -0,0 +1,74 @@
+from typing import Any, Optional
+
+from baserow.core.models import Application, TrashEntry, Group
+from baserow.core.registries import application_type_registry
+from baserow.core.signals import application_created, group_restored
+from baserow.core.trash.registries import TrashableItemType, trash_item_type_registry
+
+
+class ApplicationTrashableItemType(TrashableItemType):
+
+    type = "application"
+    model_class = Application
+
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        return trashed_item.group
+
+    def get_name(self, trashed_item: Application) -> str:
+        return trashed_item.name
+
+    def trashed_item_restored(self, trashed_item: Application, trash_entry: TrashEntry):
+        application_created.send(
+            self,
+            application=trashed_item,
+            user=None,
+        )
+
+    def permanently_delete_item(self, trashed_item: Application):
+        """
+        Deletes an application and the related relations in the correct way.
+        """
+
+        application = trashed_item.specific
+        application_type = application_type_registry.get_by_model(application)
+        application_type.pre_delete(application)
+        application.delete()
+        return application
+
+
+class GroupTrashableItemType(TrashableItemType):
+
+    type = "group"
+    model_class = Group
+
+    def get_parent(self, trashed_item: Any, parent_id: int) -> Optional[Any]:
+        return None
+
+    def get_name(self, trashed_item: Group) -> str:
+        return trashed_item.name
+
+    def trashed_item_restored(self, trashed_item: Group, trash_entry: TrashEntry):
+        """
+        Informs any clients that the group exists again.
+        """
+
+        for group_user in trashed_item.groupuser_set.all():
+            group_restored.send(self, group_user=group_user, user=None)
+
+    def permanently_delete_item(self, trashed_group: Group):
+        """
+        Deletes the provided group and all of its applications permanently.
+        """
+
+        # Select all the applications so we can delete them via the handler which is
+        # needed in order to call the pre_delete method for each application.
+        applications = (
+            trashed_group.application_set(manager="objects_and_trash")
+            .all()
+            .select_related("group")
+        )
+        application_trashable_type = trash_item_type_registry.get("application")
+        for application in applications:
+            application_trashable_type.permanently_delete_item(application)
+
+        trashed_group.delete()

backend/src/baserow/ws/signals.py

@@ -1,10 +1,11 @@
-from django.dispatch import receiver
 from django.db import transaction
+from django.dispatch import receiver
 
+from baserow.api.applications.serializers import (
+    get_application_serializer,
+)
 from baserow.api.groups.serializers import GroupSerializer, GroupUserGroupSerializer
-from baserow.api.applications.serializers import get_application_serializer
 from baserow.core import signals
-
 from .tasks import broadcast_to_group, broadcast_to_users
 
 
@@ -60,6 +61,27 @@ def group_user_updated(sender, group_user, user, **kwargs):
     )
 
 
+@receiver(signals.group_restored)
+def group_restored(sender, group_user, user, **kwargs):
+    transaction.on_commit(
+        lambda: broadcast_to_users.delay(
+            [group_user.user_id],
+            {
+                "type": "group_restored",
+                "group_id": group_user.group_id,
+                "group": GroupUserGroupSerializer(group_user).data,
+                "applications": [
+                    get_application_serializer(application).data
+                    for application in group_user.group.application_set.select_related(
+                        "content_type", "group"
+                    ).all()
+                ],
+            },
+            getattr(user, "web_socket_id", None),
+        )
+    )
+
+
 @receiver(signals.group_user_deleted)
 def group_user_deleted(sender, group_user, user, **kwargs):
     transaction.on_commit(
@@ -72,7 +94,7 @@ def group_user_deleted(sender, group_user, user, **kwargs):
 
 
 @receiver(signals.application_created)
-def application_created(sender, application, user, type_name, **kwargs):
+def application_created(sender, application, user, **kwargs):
     transaction.on_commit(
         lambda: broadcast_to_group.delay(
             application.group_id,

backend/tests/baserow/api/applications/test_application_views.py

@@ -1,5 +1,5 @@
 import pytest
-
+from django.shortcuts import reverse
 from rest_framework.status import (
     HTTP_200_OK,
     HTTP_204_NO_CONTENT,
@@ -8,8 +8,6 @@ from rest_framework.status import (
     HTTP_404_NOT_FOUND,
 )
 
-from django.shortcuts import reverse
-
 from baserow.contrib.database.models import Database
 
 
@@ -80,6 +78,31 @@ def test_list_applications(api_client, data_fixture):
     response = api_client.get(url)
     assert response.status_code == HTTP_200_OK
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": group_1.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse("api:applications:list", kwargs={"group_id": group_1.id})
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+    url = reverse(
+        "api:applications:list",
+    )
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_200_OK
+    for application in response.json():
+        assert application["group"]["id"] != group_1.id
+
 
 @pytest.mark.django_db
 def test_create_application(api_client, data_fixture):
@@ -162,6 +185,20 @@ def test_get_application(api_client, data_fixture):
     assert response_json["id"] == application.id
     assert response_json["group"]["id"] == group.id
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": application.group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse("api:applications:item", kwargs={"application_id": application.id})
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_update_application(api_client, data_fixture):

backend/tests/baserow/api/groups/test_group_invitation_views.py

@@ -12,6 +12,7 @@ from django.shortcuts import reverse
 
 from baserow.core.handler import CoreHandler
 from baserow.core.models import GroupUser, GroupInvitation
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db
@@ -585,3 +586,79 @@ def test_get_group_invitation_by_token(api_client, data_fixture):
     assert response.status_code == HTTP_200_OK
     assert response_json["id"] == invitation_2.id
     assert response_json["email_exists"] is True
+
+
+@pytest.mark.django_db
+def test_when_group_is_trashed_so_is_invitation(data_fixture, api_client):
+    user_1, token_1 = data_fixture.create_user_and_token(email="test1@test.nl")
+    visible_group = data_fixture.create_group(user=user_1)
+    trashed_group = data_fixture.create_group(user=user_1)
+    visible_invitation = data_fixture.create_group_invitation(
+        group=visible_group,
+        invited_by=user_1,
+        email="test4@test.nl",
+        permissions="ADMIN",
+        message="Test bericht 2",
+    )
+    trashed_invitation = data_fixture.create_group_invitation(
+        group=trashed_group,
+        invited_by=user_1,
+        email="test4@test.nl",
+        permissions="ADMIN",
+        message="Test bericht 2",
+    )
+    # Put the trashed_group in the trash
+    CoreHandler().delete_group(user=user_1, group=trashed_group)
+
+    # The trashed group 404's when asking for invitations
+    response = api_client.get(
+        reverse("api:groups:invitations:list", kwargs={"group_id": trashed_group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+    # The untrashed group still works like normal
+    response = api_client.get(
+        reverse("api:groups:invitations:list", kwargs={"group_id": visible_group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    assert response.status_code == HTTP_200_OK
+    response_json = response.json()
+    assert len(response_json) == 1
+    assert response_json[0]["id"] == visible_invitation.id
+
+    # can't view the invitation for the trashed group
+    response = api_client.get(
+        reverse(
+            "api:groups:invitations:item",
+            kwargs={"group_invitation_id": trashed_invitation.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_INVITATION_DOES_NOT_EXIST"
+
+    TrashHandler.restore_item(user_1, "group", trashed_group.id)
+
+    # after restoring the group is visible again
+    response = api_client.get(
+        reverse("api:groups:invitations:list", kwargs={"group_id": trashed_group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    assert response.status_code == HTTP_200_OK
+    response_json = response.json()
+    assert len(response_json) == 1
+    assert response_json[0]["id"] == trashed_invitation.id
+
+    # after restoring the invitation is visible again
+    response = api_client.get(
+        reverse(
+            "api:groups:invitations:item",
+            kwargs={"group_invitation_id": trashed_invitation.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    assert response.status_code == HTTP_200_OK
+    response_json = response.json()
+    assert response_json["id"] == trashed_invitation.id

backend/tests/baserow/api/groups/test_group_user_views.py

@@ -9,7 +9,9 @@ from rest_framework.status import (
 
 from django.shortcuts import reverse
 
+from baserow.core.handler import CoreHandler
 from baserow.core.models import GroupUser
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db
@@ -163,3 +165,30 @@ def test_delete_group_user(api_client, data_fixture):
     )
     assert response.status_code == HTTP_204_NO_CONTENT
     assert GroupUser.objects.all().count() == 1
+
+
+@pytest.mark.django_db
+def test_if_group_trashed_then_group_user_is_trashed(api_client, data_fixture):
+    user_1, token_1 = data_fixture.create_user_and_token(email="test1@test.nl")
+    trashed_group = data_fixture.create_group(user=user_1)
+    CoreHandler().delete_group(user=user_1, group=trashed_group)
+
+    response = api_client.get(
+        reverse("api:groups:users:list", kwargs={"group_id": trashed_group.id}),
+        {"permissions": "MEMBER"},
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    response_json = response.json()
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response_json["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+    TrashHandler.restore_item(user_1, "group", trashed_group.id)
+
+    response = api_client.get(
+        reverse("api:groups:users:list", kwargs={"group_id": trashed_group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token_1}",
+    )
+    response_json = response.json()
+    assert response.status_code == HTTP_200_OK
+    assert len(response_json) == 1
+    assert response_json[0]["email"] == user_1.email

backend/tests/baserow/api/groups/test_group_views.py

@@ -4,6 +4,7 @@ from rest_framework.status import HTTP_200_OK, HTTP_400_BAD_REQUEST, HTTP_404_NO
 
 from django.shortcuts import reverse
 
+from baserow.core.handler import CoreHandler
 from baserow.core.models import Group, GroupUser
 
 
@@ -155,3 +156,22 @@ def test_reorder_groups(api_client, data_fixture):
     group_user_3.refresh_from_db()
 
     assert [1, 2, 3] == [group_user_2.order, group_user_1.order, group_user_3.order]
+
+
+@pytest.mark.django_db
+def test_trashed_group_not_returned_by_views(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token(
+        email="test@test.nl", password="password", first_name="Test1"
+    )
+    trashed_group = data_fixture.create_group(user=user)
+    visible_group = data_fixture.create_group(user=user)
+
+    CoreHandler().delete_group(user=user, group=trashed_group)
+
+    response = api_client.get(
+        reverse("api:groups:list"), **{"HTTP_AUTHORIZATION": f"JWT {token}"}
+    )
+    assert response.status_code == HTTP_200_OK
+    response_json = response.json()
+    assert len(response_json) == 1
+    assert response_json[0]["id"] == visible_group.id

backend/tests/baserow/api/trash/test_trash_views.py

@@ -0,0 +1,717 @@
+import pytest
+from django.shortcuts import reverse
+from django.utils import timezone
+from freezegun import freeze_time
+from rest_framework.status import (
+    HTTP_200_OK,
+    HTTP_204_NO_CONTENT,
+    HTTP_404_NOT_FOUND,
+    HTTP_400_BAD_REQUEST,
+)
+
+from baserow.core.models import Group, TrashEntry, Application
+from baserow.core.trash.handler import TrashHandler
+
+
+@pytest.mark.django_db
+def test_deleting_a_group_moves_it_to_the_trash_and_hides_it(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.get(
+        reverse("api:groups:list"),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == []
+
+    response = api_client.get(
+        reverse(
+            "api:trash:contents",
+            kwargs={
+                "group_id": group_to_delete.id,
+            },
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "count": 1,
+        "next": None,
+        "previous": None,
+        "results": [
+            {
+                "application": None,
+                "group": group_to_delete.id,
+                "id": TrashEntry.objects.first().id,
+                "parent_trash_item_id": None,
+                "trash_item_id": group_to_delete.id,
+                "trash_item_type": "group",
+                "trashed_at": "2020-01-01T12:00:00Z",
+                "user_who_trashed": user.first_name,
+                "name": group_to_delete.name,
+                "parent_name": None,
+                "extra_description": None,
+            }
+        ],
+    }
+
+
+@pytest.mark.django_db
+def test_can_restore_a_deleted_trash_item(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "group",
+            "trash_item_id": group_to_delete.id,
+        },
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    assert Group.objects.count() == 1
+    assert Group.trash.count() == 0
+
+    response = api_client.get(
+        reverse(
+            "api:trash:contents",
+            kwargs={
+                "group_id": group_to_delete.id,
+            },
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "count": 0,
+        "next": None,
+        "previous": None,
+        "results": [],
+    }
+
+
+@pytest.mark.django_db
+def test_cant_restore_a_deleted_trash_item_if_not_in_group(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    other_user, other_token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "group",
+            "trash_item_id": group_to_delete.id,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {other_token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_USER_NOT_IN_GROUP"
+
+
+@pytest.mark.django_db
+def test_cant_restore_a_non_existent_trashed_item(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "group",
+            "trash_item_id": 99999,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_TRASH_ITEM_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_cant_restore_a_trashed_item_with_a_missing_parent(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    application = data_fixture.create_database_application(user=user, group=group)
+    table = data_fixture.create_database_table(user=user, database=application)
+    model = table.get_model()
+    row = model.objects.create()
+
+    url = reverse(
+        "api:database:rows:item", kwargs={"table_id": table.id, "row_id": row.id}
+    )
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "row",
+            "parent_trash_item_id": 99999,
+            "trash_item_id": row.id,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_TRASH_ITEM_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_cant_restore_a_trash_item_marked_for_perm_deletion(
+    api_client, data_fixture, settings
+):
+    user, token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    trashed_at = timezone.now()
+    time_when_trash_item_old_enough = trashed_at + timezone.timedelta(
+        hours=settings.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED + 1
+    )
+
+    with freeze_time(trashed_at):
+        url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    with freeze_time(time_when_trash_item_old_enough):
+        TrashHandler.mark_old_trash_for_permanent_deletion()
+        TrashHandler.permanently_delete_marked_trash()
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "group",
+            "trash_item_id": group_to_delete.id,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_TRASH_ITEM_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_can_get_trash_structure(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group()
+    normal_group = data_fixture.create_group()
+    data_fixture.create_user_group(user=user, group=group_to_delete, order=1)
+    data_fixture.create_user_group(user=user, group=normal_group, order=2)
+    # Another group for a different user which should not be displayed below
+    data_fixture.create_group()
+    application = data_fixture.create_database_application(
+        user=user, group=group_to_delete
+    )
+    trashed_application = data_fixture.create_database_application(
+        user=user, group=normal_group
+    )
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse(
+        "api:applications:item", kwargs={"application_id": trashed_application.id}
+    )
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.get(
+        reverse(
+            "api:trash:list",
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "groups": [
+            {
+                "id": group_to_delete.id,
+                "trashed": True,
+                "name": group_to_delete.name,
+                "applications": [
+                    {"id": application.id, "name": application.name, "trashed": False}
+                ],
+            },
+            {
+                "id": normal_group.id,
+                "trashed": False,
+                "name": normal_group.name,
+                "applications": [
+                    {
+                        "id": trashed_application.id,
+                        "name": trashed_application.name,
+                        "trashed": True,
+                    }
+                ],
+            },
+        ]
+    }
+
+
+@pytest.mark.django_db
+def test_getting_a_non_existent_group_returns_404(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+
+    response = api_client.get(
+        reverse(
+            "api:trash:contents",
+            kwargs={"group_id": 99999},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_getting_a_non_existent_app_returns_404(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={"group_id": group.id},
+    )
+    response = api_client.get(
+        f"{url}?application_id=99999",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_getting_a_app_for_diff_group_returns_400(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    other_group = data_fixture.create_group(user=user)
+
+    app = data_fixture.create_database_application(user=user, group=other_group)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={"group_id": group.id},
+    )
+    response = api_client.get(
+        f"{url}?application_id={app.id}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_APPLICATION_NOT_IN_GROUP"
+
+
+@pytest.mark.django_db
+def test_user_cant_get_trash_contents_for_group_they_are_not_a_member_of(
+    api_client, data_fixture
+):
+    user, token = data_fixture.create_user_and_token()
+    (
+        other_unpermissioned_user,
+        unpermissioned_token,
+    ) = data_fixture.create_user_and_token()
+
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group_to_delete.id,
+        },
+    )
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {unpermissioned_token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_USER_NOT_IN_GROUP"
+
+
+@pytest.mark.django_db
+def test_can_get_trash_contents_for_undeleted_group(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+
+    group = data_fixture.create_group(user=user)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group.id,
+        },
+    )
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "count": 0,
+        "next": None,
+        "previous": None,
+        "results": [],
+    }
+
+
+@pytest.mark.django_db
+def test_can_get_trash_contents_for_undeleted_app(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+
+    group = data_fixture.create_group(user=user)
+    app = data_fixture.create_database_application(user=user, group=group)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group.id,
+        },
+    )
+    response = api_client.get(
+        f"{url}?application_id={app.id}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "count": 0,
+        "next": None,
+        "previous": None,
+        "results": [],
+    }
+
+
+@pytest.mark.django_db
+def test_emptying_a_trashed_group_marks_it_for_perm_deletion(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group_to_delete.id,
+        },
+    )
+    response = api_client.delete(
+        f"{url}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    assert Group.objects.count() == 0
+    assert Group.trash.count() == 1
+    assert TrashEntry.objects.get(
+        trash_item_id=group_to_delete.id
+    ).should_be_permanently_deleted
+
+    response = api_client.get(
+        reverse(
+            "api:trash:contents",
+            kwargs={
+                "group_id": group_to_delete.id,
+            },
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_emptying_a_non_existent_group_returns_404(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+
+    response = api_client.delete(
+        reverse(
+            "api:trash:contents",
+            kwargs={"group_id": 99999},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_GROUP_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_emptying_a_non_existent_app_returns_404(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={"group_id": group.id},
+    )
+    response = api_client.delete(
+        f"{url}?application_id=99999",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_emptying_a_app_for_diff_group_returns_400(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    other_group = data_fixture.create_group(user=user)
+
+    app = data_fixture.create_database_application(user=user, group=other_group)
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={"group_id": group.id},
+    )
+    response = api_client.delete(
+        f"{url}?application_id={app.id}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_APPLICATION_NOT_IN_GROUP"
+
+
+@pytest.mark.django_db
+def test_user_cant_empty_trash_contents_for_group_they_are_not_a_member_of(
+    api_client, data_fixture
+):
+    user, token = data_fixture.create_user_and_token()
+    (
+        other_unpermissioned_user,
+        unpermissioned_token,
+    ) = data_fixture.create_user_and_token()
+
+    group_to_delete = data_fixture.create_group(user=user)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group_to_delete.id,
+        },
+    )
+    response = api_client.delete(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {unpermissioned_token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_USER_NOT_IN_GROUP"
+
+
+@pytest.mark.django_db
+def test_emptying_a_trashed_app_marks_it_for_perm_deletion(api_client, data_fixture):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    trashed_database = data_fixture.create_database_application(user=user, group=group)
+
+    url = reverse(
+        "api:applications:item", kwargs={"application_id": trashed_database.id}
+    )
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group.id,
+        },
+    )
+    response = api_client.delete(
+        f"{url}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    assert Application.objects.count() == 0
+    assert Application.trash.count() == 1
+    assert TrashEntry.objects.get(
+        trash_item_id=trashed_database.id
+    ).should_be_permanently_deleted
+
+    url = reverse(
+        "api:trash:contents",
+        kwargs={
+            "group_id": group.id,
+        },
+    )
+    response = api_client.get(
+        f"{url}?application_id={trashed_database.id}",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
+
+
+@pytest.mark.django_db
+def test_deleting_a_user_who_trashed_something_returns_null_user_who_trashed(
+    api_client, data_fixture
+):
+    user, token = data_fixture.create_user_and_token()
+    other_user, other_token = data_fixture.create_user_and_token()
+    group_to_delete = data_fixture.create_group(user=user)
+    data_fixture.create_user_group(user=other_user, group=group_to_delete)
+
+    url = reverse("api:groups:item", kwargs={"group_id": group_to_delete.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    user.delete()
+
+    response = api_client.get(
+        reverse(
+            "api:trash:contents",
+            kwargs={
+                "group_id": group_to_delete.id,
+            },
+        ),
+        HTTP_AUTHORIZATION=f"JWT {other_token}",
+    )
+
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "count": 1,
+        "next": None,
+        "previous": None,
+        "results": [
+            {
+                "application": None,
+                "group": group_to_delete.id,
+                "id": TrashEntry.objects.first().id,
+                "parent_trash_item_id": None,
+                "trash_item_id": group_to_delete.id,
+                "trash_item_type": "group",
+                "trashed_at": "2020-01-01T12:00:00Z",
+                "user_who_trashed": None,
+                "name": group_to_delete.name,
+                "parent_name": None,
+                "extra_description": None,
+            }
+        ],
+    }
+
+
+@pytest.mark.django_db
+def test_restoring_an_item_which_doesnt_need_parent_id_with_one_returns_error(
+    api_client, data_fixture
+):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    application = data_fixture.create_database_application(user=user, group=group)
+
+    url = reverse("api:applications:item", kwargs={"application_id": application.id})
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "application",
+            "parent_trash_item_id": 99999,
+            "trash_item_id": application.id,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_PARENT_ID_MUST_NOT_BE_PROVIDED"
+
+
+@pytest.mark.django_db
+def test_cant_restore_a_trashed_item_requiring_a_parent_id_without_providing_it(
+    api_client, data_fixture
+):
+    user, token = data_fixture.create_user_and_token()
+    group = data_fixture.create_group(user=user)
+    application = data_fixture.create_database_application(user=user, group=group)
+    table = data_fixture.create_database_table(user=user, database=application)
+    model = table.get_model()
+    row = model.objects.create()
+
+    url = reverse(
+        "api:database:rows:item", kwargs={"table_id": table.id, "row_id": row.id}
+    )
+    with freeze_time("2020-01-01 12:00"):
+        response = api_client.delete(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.patch(
+        reverse(
+            "api:trash:restore",
+        ),
+        {
+            "trash_item_type": "row",
+            "trash_item_id": row.id,
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    assert response.status_code == HTTP_400_BAD_REQUEST
+    assert response.json()["error"] == "ERROR_PARENT_ID_MUST_BE_PROVIDED"

backend/tests/baserow/contrib/database/api/fields/test_field_views.py

@@ -5,6 +5,7 @@ from rest_framework.status import (
     HTTP_400_BAD_REQUEST,
     HTTP_401_UNAUTHORIZED,
     HTTP_404_NOT_FOUND,
+    HTTP_204_NO_CONTENT,
 )
 
 from django.shortcuts import reverse
@@ -107,6 +108,21 @@ def test_list_fields(api_client, data_fixture):
     )
     assert response.status_code == HTTP_200_OK
 
+    response = api_client.delete(
+        reverse(
+            "api:groups:item",
+            kwargs={"group_id": table_1.database.group.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {jwt_token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+    response = api_client.get(
+        reverse("api:database:fields:list", kwargs={"table_id": table_1.id}),
+        **{"HTTP_AUTHORIZATION": f"JWT {jwt_token}"},
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_TABLE_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_create_field(api_client, data_fixture):
@@ -239,6 +255,19 @@ def test_get_field(api_client, data_fixture):
     assert response_json["table_id"] == text.table_id
     assert not response_json["text_default"]
 
+    response = api_client.delete(
+        reverse(
+            "api:groups:item",
+            kwargs={"group_id": table.database.group.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+    url = reverse("api:database:fields:item", kwargs={"field_id": text.id})
+    response = api_client.get(url, format="json", HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_FIELD_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_update_field(api_client, data_fixture):

backend/tests/baserow/contrib/database/api/tables/test_table_views.py

@@ -42,6 +42,17 @@ def test_list_tables(api_client, data_fixture):
     assert response.status_code == HTTP_404_NOT_FOUND
     assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": database.group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse("api:database:tables:list", kwargs={"database_id": database.id})
+    response = api_client.get(url, **{"HTTP_AUTHORIZATION": f"JWT {token}"})
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_APPLICATION_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_create_table(api_client, data_fixture):

backend/tests/baserow/contrib/database/api/views/test_view_views.py

@@ -78,6 +78,17 @@ def test_list_views(api_client, data_fixture):
     response = api_client.get(url)
     assert response.status_code == HTTP_200_OK
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": table_1.database.group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse("api:database:views:list", kwargs={"table_id": table_1.id})
+    response = api_client.get(url)
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_TABLE_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_list_views_including_filters(api_client, data_fixture):
@@ -326,6 +337,20 @@ def test_get_view(api_client, data_fixture):
     assert response_json["filters"][0]["value"] == filter.value
     assert response_json["sortings"] == []
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": view.table.database.group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    url = reverse("api:database:views:item", kwargs={"view_id": view.id})
+    response = api_client.get(
+        url,
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_VIEW_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_update_view(api_client, data_fixture):
@@ -548,6 +573,18 @@ def test_list_view_filters(api_client, data_fixture):
     assert response_json[0]["value"] == filter_1.value
     assert response_json[1]["id"] == filter_2.id
 
+    response = api_client.delete(
+        reverse("api:groups:item", kwargs={"group_id": table_1.database.group.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+    response = api_client.get(
+        reverse("api:database:views:list_filters", kwargs={"view_id": view_1.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_VIEW_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_create_view_filter(api_client, data_fixture):
@@ -701,6 +738,24 @@ def test_get_view_filter(api_client, data_fixture):
     assert response_json["type"] == "equal"
     assert response_json["value"] == "test"
 
+    response = api_client.delete(
+        reverse(
+            "api:groups:item",
+            kwargs={"group_id": filter_1.view.table.database.group.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.get(
+        reverse(
+            "api:database:views:filter_item", kwargs={"view_filter_id": filter_1.id}
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_VIEW_FILTER_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_update_view_filter(api_client, data_fixture):
@@ -926,6 +981,22 @@ def test_list_view_sortings(api_client, data_fixture):
     assert response_json[0]["order"] == sort_1.order
     assert response_json[1]["id"] == sort_2.id
 
+    response = api_client.delete(
+        reverse(
+            "api:groups:item",
+            kwargs={"group_id": view_1.table.database.group.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.get(
+        reverse("api:database:views:list_sortings", kwargs={"view_id": view_1.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_VIEW_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_create_view_sort(api_client, data_fixture):
@@ -1092,6 +1163,22 @@ def test_get_view_sort(api_client, data_fixture):
     assert response_json["field"] == first.field_id
     assert response_json["order"] == "DESC"
 
+    response = api_client.delete(
+        reverse(
+            "api:groups:item",
+            kwargs={"group_id": sort_1.view.table.database.group.id},
+        ),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_204_NO_CONTENT
+
+    response = api_client.get(
+        reverse("api:database:views:sort_item", kwargs={"view_sort_id": sort_1.id}),
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+    assert response.status_code == HTTP_404_NOT_FOUND
+    assert response.json()["error"] == "ERROR_VIEW_SORT_DOES_NOT_EXIST"
+
 
 @pytest.mark.django_db
 def test_update_view_sort(api_client, data_fixture):

backend/tests/baserow/contrib/database/export/test_export_handler.py

@@ -234,7 +234,7 @@ def test_can_export_every_interesting_different_field_to_csv(
 
 
 def run_export_job_over_interesting_table(data_fixture, storage_mock, options):
-    table, user = setup_interesting_test_table(data_fixture)
+    table, user, _ = setup_interesting_test_table(data_fixture)
     grid_view = data_fixture.create_grid_view(table=table)
     job, contents = run_export_job_with_mock_storage(
         table, grid_view, storage_mock, user, options

backend/tests/baserow/contrib/database/field/test_field_handler.py

@@ -754,6 +754,7 @@ def test_delete_field(send_mock, data_fixture):
     field_id = text_field.id
     handler.delete_field(user=user, field=text_field)
     assert Field.objects.all().count() == 0
+    assert Field.trash.all().count() == 1
     assert TextField.objects.all().count() == 0
 
     send_mock.assert_called_once()
@@ -761,10 +762,6 @@ def test_delete_field(send_mock, data_fixture):
     assert send_mock.call_args[1]["field"].id == field_id
     assert send_mock.call_args[1]["user"].id == user.id
 
-    table_model = table.get_model()
-    field_name = f"field_{text_field.id}"
-    assert field_name not in [field.name for field in table_model._meta.get_fields()]
-
     primary = data_fixture.create_text_field(table=table, primary=True)
     with pytest.raises(CannotDeletePrimaryField):
         handler.delete_field(user=user, field=primary)

backend/tests/baserow/contrib/database/field/test_field_types.py

@@ -15,6 +15,7 @@ from baserow.contrib.database.fields.models import (
 from baserow.contrib.database.fields.handler import FieldHandler
 from baserow.contrib.database.fields.registries import field_type_registry
 from baserow.contrib.database.rows.handler import RowHandler
+from tests.test_utils import setup_interesting_test_table
 
 
 @pytest.mark.django_db
@@ -435,3 +436,37 @@ def test_phone_number_field_type(data_fixture):
 
     field_handler.delete_field(user=user, field=phone_number_field)
     assert len(PhoneNumberField.objects.all()) == 3
+
+
+@pytest.mark.django_db
+def test_human_readable_values(data_fixture):
+    table, user, row = setup_interesting_test_table(data_fixture)
+    model = table.get_model()
+    results = {}
+    for field in model._field_objects.values():
+        value = field["type"].get_human_readable_value(
+            getattr(row, field["name"]), field
+        )
+        results[field["field"].name] = value
+
+    assert results == {
+        "boolean": "True",
+        "date_eu": "01/02/2020",
+        "date_us": "02/01/2020",
+        "datetime_eu": "01/02/2020 01:23",
+        "datetime_us": "02/01/2020 01:23",
+        "decimal_link_row": "1.234,-123.456,unnamed row 3",
+        "email": "test@example.com",
+        "file": "a.txt,b.txt",
+        "file_link_row": "name.txt,unnamed row 2",
+        "link_row": "linked_row_1,linked_row_2,unnamed row 3",
+        "long_text": "long_text",
+        "negative_decimal": "-1.2",
+        "negative_int": "-1",
+        "phone_number": "+4412345678",
+        "positive_decimal": "1.2",
+        "positive_int": "1",
+        "single_select": "A",
+        "text": "text",
+        "url": "https://www.google.com",
+    }

backend/tests/baserow/contrib/database/field/test_link_row_field_type.py

@@ -17,6 +17,7 @@ from baserow.contrib.database.fields.exceptions import (
     LinkRowTableNotProvided,
 )
 from baserow.contrib.database.rows.handler import RowHandler
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db
@@ -194,10 +195,6 @@ def test_link_row_field_type(data_fixture):
     # Delete the existing field. Alter that the related field should be deleted and
     # no table named _relation_ should exist.
     field_handler.delete_field(user, link_field_1)
-    assert LinkRowField.objects.all().count() == 0
-    for t in connection.introspection.table_names():
-        if "_relation_" in t:
-            assert False
 
     # Change a the text field back into a link row field.
     link_field_2 = field_handler.update_field(
@@ -356,7 +353,9 @@ def test_link_row_field_type_rows(data_fixture):
     # Just check if the field can be deleted can be deleted.
     field_handler.delete_field(user=user, field=link_row_field)
     # We expect only the primary field to be left.
-    assert Field.objects.all().count() == 1
+    objects_all = Field.objects.all()
+    print(objects_all.query)
+    assert objects_all.count() == 1
 
 
 @pytest.mark.django_db
@@ -662,6 +661,7 @@ def test_link_row_field_type_api_row_views(api_client, data_fixture):
         format="json",
         HTTP_AUTHORIZATION=f"JWT {token}",
     )
+
     response_json = response.json()
     row_id = response_json["id"]
     assert response.status_code == HTTP_200_OK
@@ -802,3 +802,104 @@ def test_import_export_link_row_field(data_fixture, user_tables_in_separate_db):
     assert [
         r.id for r in getattr(imported_row, f"field_{imported_link_row_field.id}").all()
     ] == [imported_c_row.id, imported_c_row_2.id]
+
+
+@pytest.mark.django_db
+def test_creating_a_linked_row_pointing_at_trashed_row_works_but_does_not_display(
+    data_fixture, api_client
+):
+    user, token = data_fixture.create_user_and_token()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    table_with_trashed_row = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+    table_linking_to_trashed_row = data_fixture.create_database_table(
+        name="Cars", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user,
+        table=table_with_trashed_row,
+        type_name="text",
+        name="Name",
+        primary=True,
+    )
+    trashed_row = row_handler.create_row(
+        user=user,
+        table=table_with_trashed_row,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=table_linking_to_trashed_row,
+        type_name="link_row",
+        name="customer",
+        link_row_table=table_with_trashed_row,
+    )
+    # Create a primary field and some example data for the cars table.
+    field_handler.create_field(
+        user=user,
+        table=table_linking_to_trashed_row,
+        type_name="text",
+        name="Name",
+        primary=True,
+    )
+    TrashHandler.trash(
+        user,
+        database.group,
+        database,
+        trashed_row,
+        parent_id=table_with_trashed_row.id,
+    )
+
+    response = api_client.post(
+        reverse(
+            "api:database:rows:list",
+            kwargs={"table_id": table_linking_to_trashed_row.id},
+        ),
+        {
+            f"field_{link_field_1.id}": [trashed_row.id],
+        },
+        format="json",
+        HTTP_AUTHORIZATION=f"JWT {token}",
+    )
+
+    response_json = response.json()
+    assert response.status_code == HTTP_200_OK
+
+    # Even though the call succeeded, the linked row is not returned
+    assert response_json[f"field_{link_field_1.id}"] == []
+
+    row_id = response_json["id"]
+
+    url = reverse(
+        "api:database:rows:item",
+        kwargs={"table_id": table_linking_to_trashed_row.id, "row_id": row_id},
+    )
+    response = api_client.get(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_200_OK
+    # Other endpoints also don't return this connection made whilst trashed
+    assert response.json()[f"field_{link_field_1.id}"] == []
+
+    TrashHandler.restore_item(
+        user,
+        "row",
+        row_id,
+        parent_trash_item_id=table_with_trashed_row.id,
+    )
+
+    url = reverse(
+        "api:database:rows:item",
+        kwargs={"table_id": table_linking_to_trashed_row.id, "row_id": row_id},
+    )
+    response = api_client.get(url, HTTP_AUTHORIZATION=f"JWT {token}")
+    assert response.status_code == HTTP_200_OK
+    # Now that the row was un-trashed, it appears.
+    linked_field_values = response.json()[f"field_{link_field_1.id}"]
+    assert len(linked_field_values) == 1
+    assert linked_field_values[0]["id"] == trashed_row.id

backend/tests/baserow/contrib/database/rows/test_rows_handler.py

@@ -9,6 +9,7 @@ from django.db import models
 from baserow.core.exceptions import UserNotInGroup
 from baserow.contrib.database.rows.handler import RowHandler
 from baserow.contrib.database.rows.exceptions import RowDoesNotExist
+from baserow.core.trash.handler import TrashHandler
 
 
 def test_get_field_ids_from_dict():
@@ -432,6 +433,9 @@ def test_delete_row(before_send_mock, send_mock, data_fixture):
     row_id = row.id
     handler.delete_row(user=user, table=table, row_id=row.id)
     assert model.objects.all().count() == 1
+    assert model.trash.all().count() == 1
+    row.refresh_from_db()
+    assert row.trashed
 
     before_send_mock.assert_called_once()
     assert before_send_mock.call_args[1]["row"]
@@ -446,3 +450,45 @@ def test_delete_row(before_send_mock, send_mock, data_fixture):
     assert send_mock.call_args[1]["table"].id == table.id
     assert send_mock.call_args[1]["model"]._generated_table_model
     assert send_mock.call_args[1]["before_return"] == before_send_mock.return_value
+
+
+@pytest.mark.django_db
+@patch("baserow.contrib.database.rows.signals.row_created.send")
+def test_restore_row(send_mock, data_fixture):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(name="Car", user=user)
+    name_field = data_fixture.create_text_field(
+        table=table, name="Name", text_default="Test"
+    )
+    speed_field = data_fixture.create_number_field(
+        table=table, name="Max speed", number_negative=True
+    )
+    price_field = data_fixture.create_number_field(
+        table=table,
+        name="Price",
+        number_type="DECIMAL",
+        number_decimal_places=2,
+        number_negative=False,
+    )
+
+    handler = RowHandler()
+
+    row_1 = handler.create_row(
+        user=user,
+        table=table,
+        values={
+            name_field.id: "Tesla",
+            speed_field.id: 240,
+            f"field_{price_field.id}": 59999.99,
+        },
+    )
+
+    handler.delete_row(user, table, row_1.id)
+    TrashHandler.restore_item(user, "row", row_1.id, parent_trash_item_id=table.id)
+
+    assert len(send_mock.call_args) == 2
+    assert send_mock.call_args[1]["row"].id == row_1.id
+    assert send_mock.call_args[1]["user"] is None
+    assert send_mock.call_args[1]["table"].id == table.id
+    assert send_mock.call_args[1]["before"] is None
+    assert send_mock.call_args[1]["model"]._generated_table_model

backend/tests/baserow/contrib/database/table/test_table_handler.py

@@ -21,6 +21,7 @@ from baserow.contrib.database.fields.models import (
     BooleanField,
 )
 from baserow.contrib.database.views.models import GridView, GridViewFieldOptions
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db
@@ -42,6 +43,17 @@ def test_get_database_table(data_fixture):
     table_copy = handler.get_table(table_id=table.id)
     assert table_copy.id == table.id
 
+    TrashHandler.trash(user, table.database.group, table.database, table.database)
+
+    with pytest.raises(TableDoesNotExist):
+        handler.get_table(table_id=table.id)
+
+    TrashHandler.restore_item(user, "application", table.database.id)
+
+    TrashHandler.trash(user, table.database.group, None, table.database.group)
+    with pytest.raises(TableDoesNotExist):
+        handler.get_table(table_id=table.id)
+
 
 @pytest.mark.django_db
 @patch("baserow.contrib.database.table.signals.table_created.send")
@@ -326,7 +338,7 @@ def test_delete_database_table(send_mock, data_fixture):
         handler.delete_table(user=user_2, table=table)
 
     assert Table.objects.all().count() == 1
-    assert f"database_table_{table.id}" in connection.introspection.table_names()
+    assert Table.trash.all().count() == 0
 
     table_id = table.id
     handler.delete_table(user=user, table=table)
@@ -336,4 +348,5 @@ def test_delete_database_table(send_mock, data_fixture):
     assert send_mock.call_args[1]["user"].id == user.id
 
     assert Table.objects.all().count() == 0
-    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+    assert Table.trash.all().count() == 1
+    assert f"database_table_{table.id}" in connection.introspection.table_names()

backend/tests/baserow/contrib/database/table/test_table_models.py

@@ -34,7 +34,7 @@ def test_group_user_get_next_order(data_fixture):
 
 @pytest.mark.django_db
 def test_get_table_model(data_fixture):
-    default_model_fields_count = 3
+    default_model_fields_count = 4
     table = data_fixture.create_database_table(name="Cars")
     text_field = data_fixture.create_text_field(
         table=table, order=0, name="Color", text_default="white"

backend/tests/baserow/contrib/database/trash/test_database_trash_types.py

@@ -0,0 +1,748 @@
+from unittest.mock import patch
+
+import pytest
+from django.db import connection
+
+from baserow.contrib.database.fields.handler import FieldHandler
+from baserow.contrib.database.fields.models import Field, TextField, LinkRowField
+from baserow.contrib.database.rows.handler import RowHandler
+from baserow.contrib.database.table.models import Table
+from baserow.contrib.database.views.handler import ViewHandler
+from baserow.core.models import TrashEntry
+from baserow.core.trash.exceptions import (
+    ParentIdMustBeProvidedException,
+    ParentIdMustNotBeProvidedException,
+)
+from baserow.core.trash.handler import TrashHandler
+
+
+@pytest.mark.django_db
+def test_delete_row(data_fixture):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(name="Car", user=user)
+    data_fixture.create_text_field(table=table, name="Name", text_default="Test")
+
+    handler = RowHandler()
+    model = table.get_model()
+    row = handler.create_row(user=user, table=table)
+    handler.create_row(user=user, table=table)
+
+    TrashHandler.permanently_delete(row)
+    assert model.objects.all().count() == 1
+
+
+@pytest.mark.django_db
+def test_perm_deleting_many_rows_at_once_only_looks_up_the_model_once(
+    data_fixture, django_assert_num_queries
+):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(name="Car", user=user)
+    data_fixture.create_text_field(table=table, name="Name", text_default="Test")
+
+    handler = RowHandler()
+    model = table.get_model()
+    row_1 = handler.create_row(user=user, table=table)
+
+    TrashHandler.trash(
+        user, table.database.group, table.database, row_1, parent_id=table.id
+    )
+    assert model.objects.all().count() == 0
+    assert model.trash.all().count() == 1
+    assert TrashEntry.objects.count() == 1
+
+    TrashEntry.objects.update(should_be_permanently_deleted=True)
+
+    with django_assert_num_queries(9):
+        TrashHandler.permanently_delete_marked_trash()
+
+    row_2 = handler.create_row(user=user, table=table)
+    row_3 = handler.create_row(user=user, table=table)
+    TrashHandler.trash(
+        user, table.database.group, table.database, row_2, parent_id=table.id
+    )
+    TrashHandler.trash(
+        user, table.database.group, table.database, row_3, parent_id=table.id
+    )
+
+    assert model.objects.all().count() == 0
+    assert model.trash.all().count() == 2
+    assert TrashEntry.objects.count() == 2
+
+    TrashEntry.objects.update(should_be_permanently_deleted=True)
+
+    # We only want five more queries when deleting 2 rows instead of 1 compared to
+    # above:
+    # 1. A query to lookup the extra row we are deleting
+    # 2. A query to delete said row
+    # 3. A query to delete it's trash entry.
+    # 4. Queries to open and close transactions for each deletion
+    # If we weren't caching the table models an extra number of queries would be first
+    # performed to lookup the table information which breaks this assertion.
+    with django_assert_num_queries(14):
+        TrashHandler.permanently_delete_marked_trash()
+
+
+@pytest.mark.django_db
+def test_delete_row_when_in_separate_user_db(data_fixture, user_tables_in_separate_db):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(name="Car", user=user)
+    data_fixture.create_text_field(table=table, name="Name", text_default="Test")
+
+    handler = RowHandler()
+    row = handler.create_row(user=user, table=table)
+    handler.create_row(user=user, table=table)
+
+    TrashHandler.trash(
+        user, table.database.group, table.database, row, parent_id=table.id
+    )
+    model = table.get_model()
+    assert model.objects.all().count() == 1
+    assert model.trash.all().count() == 1
+
+    TrashHandler.permanently_delete(row)
+    assert model.objects.all().count() == 1
+    assert model.trash.all().count() == 0
+
+
+@pytest.mark.django_db
+def test_perm_delete_table(data_fixture):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    database = data_fixture.create_database_application(group=group)
+    table = data_fixture.create_database_table(user=user, database=database)
+
+    assert Table.objects.all().count() == 1
+    assert f"database_table_{table.id}" in connection.introspection.table_names()
+
+    TrashHandler.permanently_delete(table)
+
+    assert Table.objects.all().count() == 0
+    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+
+
+@pytest.mark.django_db
+def test_perm_delete_field(data_fixture):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(user=user)
+    text_field = data_fixture.create_text_field(table=table)
+
+    assert Field.objects.all().count() == 1
+    assert TextField.objects.all().count() == 1
+    TrashHandler.permanently_delete(text_field)
+    assert Field.objects.all().count() == 0
+    assert Field.trash.all().count() == 0
+    assert TextField.objects.all().count() == 0
+
+    table_model = table.get_model()
+    field_name = f"field_{text_field.id}"
+    assert field_name not in [field.name for field in table_model._meta.get_fields()]
+    assert f"trashed_{field_name}" not in [
+        field.name for field in table_model._meta.get_fields()
+    ]
+
+
+@pytest.mark.django_db
+def test_perm_delete_link_row_field(data_fixture):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    table = data_fixture.create_database_table(name="Example", database=database)
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+    cars_table = data_fixture.create_database_table(name="Cars", database=database)
+    data_fixture.create_database_table(name="Unrelated")
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "Jane"},
+    )
+
+    # Create a primary field and some example data for the cars table.
+    cars_primary_field = field_handler.create_field(
+        user=user, table=cars_table, type_name="text", name="Name", primary=True
+    )
+    row_handler.create_row(
+        user=user, table=cars_table, values={f"field_{cars_primary_field.id}": "BMW"}
+    )
+    row_handler.create_row(
+        user=user, table=cars_table, values={f"field_{cars_primary_field.id}": "Audi"}
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=table,
+        type_name="link_row",
+        name="Customer",
+        link_row_table=customers_table,
+    )
+    TrashHandler.permanently_delete(link_field_1)
+    assert LinkRowField.objects.all().count() == 0
+    for t in connection.introspection.table_names():
+        if "_relation_" in t:
+            assert False
+
+
+@pytest.mark.django_db
+def test_trashing_a_table_with_link_fields_pointing_at_it_also_trashes_those_fields(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    table = data_fixture.create_database_table(name="Example", database=database)
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+    cars_table = data_fixture.create_database_table(name="Cars", database=database)
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "Jane"},
+    )
+
+    # Create a primary field and some example data for the cars table.
+    cars_primary_field = field_handler.create_field(
+        user=user, table=cars_table, type_name="text", name="Name", primary=True
+    )
+    row_handler.create_row(
+        user=user, table=cars_table, values={f"field_{cars_primary_field.id}": "BMW"}
+    )
+    row_handler.create_row(
+        user=user, table=cars_table, values={f"field_{cars_primary_field.id}": "Audi"}
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=table,
+        type_name="link_row",
+        name="Customer",
+        link_row_table=customers_table,
+    )
+    TrashHandler.trash(user, database.group, database, customers_table)
+
+    link_field_1.refresh_from_db()
+    assert link_field_1.trashed
+
+
+@pytest.mark.django_db
+def test_trashed_row_entry_includes_the_rows_primary_key_value_as_an_extra_description(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    trash_entry = TrashHandler.trash(
+        user, database.group, database, row, parent_id=customers_table.id
+    )
+
+    assert trash_entry.extra_description == "John"
+    assert trash_entry.name == str(row.id)
+    assert trash_entry.parent_name == "Customers"
+
+
+@pytest.mark.django_db
+def test_trashed_row_entry_extra_description_is_unnamed_when_no_value_pk(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={},
+    )
+    trash_entry = TrashHandler.trash(
+        user, database.group, database, row, parent_id=customers_table.id
+    )
+
+    assert trash_entry.extra_description == f"unnamed row {row.id}"
+    assert trash_entry.name == str(row.id)
+    assert trash_entry.parent_name == "Customers"
+
+
+@pytest.mark.django_db
+def test_restoring_a_trashed_link_field_restores_the_opposing_field_also(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    table = data_fixture.create_database_table(database=database)
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "Jane"},
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=table,
+        type_name="link_row",
+        name="Customer",
+        link_row_table=customers_table,
+    )
+    TrashHandler.trash(user, database.group, database, link_field_1)
+
+    assert LinkRowField.trash.count() == 2
+
+    TrashHandler.restore_item(user, "field", link_field_1.id)
+
+    assert LinkRowField.objects.count() == 2
+
+
+@pytest.mark.django_db
+def test_trashing_a_row_hides_it_from_a_link_row_field_pointing_at_it(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+    cars_table = data_fixture.create_database_table(name="Cars", database=database)
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    john_row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    jane_row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "Jane"},
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=cars_table,
+        type_name="link_row",
+        name="customer",
+        link_row_table=customers_table,
+    )
+    # Create a primary field and some example data for the cars table.
+    cars_primary_field = field_handler.create_field(
+        user=user, table=cars_table, type_name="text", name="Name", primary=True
+    )
+    linked_row_pointing_at_john = row_handler.create_row(
+        user=user,
+        table=cars_table,
+        values={
+            f"field_{cars_primary_field.id}": "BMW",
+            f"field_{link_field_1.id}": [john_row.id],
+        },
+    )
+    linked_row_pointing_at_jane = row_handler.create_row(
+        user=user,
+        table=cars_table,
+        values={
+            f"field_{cars_primary_field.id}": "Audi",
+            f"field_{link_field_1.id}": [jane_row.id],
+        },
+    )
+
+    cars_model = cars_table.get_model(attribute_names=True)
+    assert list(cars_model.objects.values_list("customer", flat=True)) == [
+        john_row.id,
+        jane_row.id,
+    ]
+    row = RowHandler().get_row(user, cars_table, linked_row_pointing_at_john.id)
+    assert list(
+        getattr(row, f"field_{link_field_1.id}").values_list("id", flat=True)
+    ) == [john_row.id]
+
+    TrashHandler.trash(
+        user, database.group, database, john_row, parent_id=customers_table.id
+    )
+
+    row = RowHandler().get_row(user, cars_table, linked_row_pointing_at_john.id)
+    assert list(getattr(row, f"field_{link_field_1.id}").all()) == []
+    row = RowHandler().get_row(user, cars_table, linked_row_pointing_at_jane.id)
+    assert list(
+        getattr(row, f"field_{link_field_1.id}").values_list("id", flat=True)
+    ) == [jane_row.id]
+
+
+@pytest.mark.django_db
+def test_a_trashed_linked_row_pointing_at_a_trashed_row_is_restored_correctly(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+    cars_table = data_fixture.create_database_table(name="Cars", database=database)
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    john_row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+    jane_row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "Jane"},
+    )
+
+    link_field_1 = field_handler.create_field(
+        user=user,
+        table=cars_table,
+        type_name="link_row",
+        name="customer",
+        link_row_table=customers_table,
+    )
+    # Create a primary field and some example data for the cars table.
+    cars_primary_field = field_handler.create_field(
+        user=user, table=cars_table, type_name="text", name="Name", primary=True
+    )
+    linked_row_pointing_at_john = row_handler.create_row(
+        user=user,
+        table=cars_table,
+        values={
+            f"field_{cars_primary_field.id}": "BMW",
+            f"field_{link_field_1.id}": [john_row.id],
+        },
+    )
+    row_handler.create_row(
+        user=user,
+        table=cars_table,
+        values={
+            f"field_{cars_primary_field.id}": "Audi",
+            f"field_{link_field_1.id}": [jane_row.id],
+        },
+    )
+
+    TrashHandler.trash(
+        user,
+        database.group,
+        database,
+        linked_row_pointing_at_john,
+        parent_id=cars_table.id,
+    )
+    TrashHandler.trash(
+        user, database.group, database, john_row, parent_id=customers_table.id
+    )
+    TrashHandler.restore_item(
+        user, "row", linked_row_pointing_at_john.id, parent_trash_item_id=cars_table.id
+    )
+
+    row = RowHandler().get_row(user, cars_table, linked_row_pointing_at_john.id)
+    assert list(getattr(row, f"field_{link_field_1.id}").all()) == []
+
+    TrashHandler.restore_item(
+        user, "row", john_row.id, parent_trash_item_id=customers_table.id
+    )
+
+    row = RowHandler().get_row(user, cars_table, linked_row_pointing_at_john.id)
+    assert list(
+        getattr(row, f"field_{link_field_1.id}").values_list("id", flat=True)
+    ) == [john_row.id]
+
+
+@pytest.mark.django_db
+def test_a_parent_id_must_be_provided_when_trashing_or_restoring_a_row(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    john_row = row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={f"field_{customers_primary_field.id}": "John"},
+    )
+
+    with pytest.raises(ParentIdMustBeProvidedException):
+        TrashHandler.trash(
+            user,
+            database.group,
+            database,
+            john_row,
+        )
+
+    TrashHandler.trash(
+        user, database.group, database, john_row, parent_id=customers_table.id
+    )
+
+    with pytest.raises(ParentIdMustBeProvidedException):
+        TrashHandler.restore_item(user, "row", john_row.id)
+
+
+@pytest.mark.django_db
+def test_a_parent_id_must_not_be_provided_when_trashing_or_restoring_an_app(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    with pytest.raises(ParentIdMustNotBeProvidedException):
+        TrashHandler.trash(
+            user, database.group, database, database, parent_id=database.group.id
+        )
+
+    TrashHandler.trash(user, database.group, database, database)
+
+    with pytest.raises(ParentIdMustNotBeProvidedException):
+        TrashHandler.restore_item(
+            user, "application", database.id, parent_trash_item_id=database.group.id
+        )
+
+
+@pytest.mark.django_db
+def test_trashing_a_field_with_a_filter_trashes_the_filter(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    other_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Other"
+    )
+    grid_view = data_fixture.create_grid_view(user=user, table=customers_table)
+    data_fixture.create_view_filter(
+        view=grid_view, user=user, field=other_field, value="Steve"
+    )
+
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={
+            f"field_{customers_primary_field.id}": "John",
+            f"field_{other_field.id}": "Test",
+        },
+    )
+
+    TrashHandler.trash(
+        user,
+        database.group,
+        database,
+        other_field,
+    )
+
+    model = customers_table.get_model()
+    filtered_qs = ViewHandler().apply_filters(grid_view, model.objects.all())
+    assert filtered_qs.count() == 1
+    TrashHandler.restore_item(
+        user,
+        "field",
+        other_field.id,
+    )
+
+    model = customers_table.get_model()
+    filtered_qs = ViewHandler().apply_filters(grid_view, model.objects.all())
+    assert filtered_qs.count() == 0
+
+
+@pytest.mark.django_db
+def test_trashing_a_field_with_a_sort_trashes_the_sort(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    database = data_fixture.create_database_application(user=user, name="Placeholder")
+    customers_table = data_fixture.create_database_table(
+        name="Customers", database=database
+    )
+
+    field_handler = FieldHandler()
+    row_handler = RowHandler()
+
+    # Create a primary field and some example data for the customers table.
+    customers_primary_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Name", primary=True
+    )
+    other_field = field_handler.create_field(
+        user=user, table=customers_table, type_name="text", name="Other"
+    )
+    grid_view = data_fixture.create_grid_view(user=user, table=customers_table)
+    data_fixture.create_view_sort(
+        view=grid_view, user=user, field=other_field, order="ASC"
+    )
+
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={
+            f"field_{customers_primary_field.id}": "1",
+            f"field_{other_field.id}": "2",
+        },
+    )
+    row_handler.create_row(
+        user=user,
+        table=customers_table,
+        values={
+            f"field_{customers_primary_field.id}": "2",
+            f"field_{other_field.id}": "1",
+        },
+    )
+
+    TrashHandler.trash(
+        user,
+        database.group,
+        database,
+        other_field,
+    )
+
+    model = customers_table.get_model()
+    filtered_qs = ViewHandler().apply_sorting(grid_view, model.objects.all())
+    assert list(
+        filtered_qs.values_list(f"field_{customers_primary_field.id}", flat=True)
+    ) == ["1", "2"]
+
+    TrashHandler.restore_item(
+        user,
+        "field",
+        other_field.id,
+    )
+
+    model = customers_table.get_model()
+    filtered_qs = ViewHandler().apply_sorting(grid_view, model.objects.all())
+    assert list(
+        filtered_qs.values_list(f"field_{customers_primary_field.id}", flat=True)
+    ) == ["2", "1"]
+
+
+@pytest.mark.django_db(transaction=True)
+def test_can_perm_delete_tables_in_another_user_db(
+    data_fixture,
+    user_tables_in_separate_db,
+):
+    patcher = patch("baserow.core.models.TrashEntry.delete")
+    trash_entry_delete = patcher.start()
+
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(name="Car", user=user)
+    data_fixture.create_text_field(table=table, name="Name", text_default="Test")
+
+    TrashHandler.trash(user, table.database.group, table.database, table)
+    assert TrashEntry.objects.count() == 1
+    assert (
+        f"database_table_{table.id}"
+        in user_tables_in_separate_db.introspection.table_names()
+    )
+
+    TrashEntry.objects.update(should_be_permanently_deleted=True)
+
+    trash_entry_delete.side_effect = RuntimeError("Force the outer transaction to fail")
+    with pytest.raises(RuntimeError):
+        TrashHandler.permanently_delete_marked_trash()
+
+    assert Table.trash.filter(id=table.id).exists()
+    assert TrashEntry.objects.count() == 1
+    # Even though the transaction rolled back and restored the Table and TrashEntry the
+    # actual table was still deleted as that happened in a different connection!
+    assert (
+        f"database_table_{table.id}"
+        not in user_tables_in_separate_db.introspection.table_names()
+    )
+
+    # Now make it so the deletion will work the second time, as long as it handles
+    # the actual table no longer being there.
+    patcher.stop()
+
+    TrashHandler.permanently_delete_marked_trash()
+
+    assert not Table.trash.filter(id=table.id).exists()
+    assert TrashEntry.objects.count() == 0
+    assert (
+        f"database_table_{table.id}"
+        not in user_tables_in_separate_db.introspection.table_names()
+    )

backend/tests/baserow/contrib/database/view/test_view_handler.py

@@ -26,6 +26,7 @@ from baserow.contrib.database.views.exceptions import (
 from baserow.contrib.database.fields.models import Field
 from baserow.contrib.database.fields.handler import FieldHandler
 from baserow.contrib.database.fields.exceptions import FieldNotInTable
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db
@@ -61,6 +62,16 @@ def test_get_view(data_fixture):
             view_id=grid.id, base_queryset=View.objects.prefetch_related("UNKNOWN")
         )
 
+    # If the table is trashed the view should not be available.
+    TrashHandler.trash(user, grid.table.database.group, grid.table.database, grid.table)
+    with pytest.raises(ViewDoesNotExist):
+        handler.get_view(view_id=grid.id, view_model=GridView)
+
+    # Restoring the table should restore the view
+    TrashHandler.restore_item(user, "table", grid.table.id)
+    view = handler.get_view(view_id=grid.id, view_model=GridView)
+    assert view.id == grid.id
+
 
 @pytest.mark.django_db
 @patch("baserow.contrib.database.views.signals.view_created.send")
@@ -243,6 +254,37 @@ def test_delete_view(send_mock, data_fixture):
     assert send_mock.call_args[1]["user"].id == user.id
 
 
+@pytest.mark.django_db
+def test_trashed_fields_are_not_included_in_grid_view_field_options(data_fixture):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(user=user)
+    grid_view = data_fixture.create_grid_view(table=table)
+    field_1 = data_fixture.create_text_field(table=table)
+    field_2 = data_fixture.create_text_field(table=table)
+
+    ViewHandler().update_grid_view_field_options(
+        user=user,
+        grid_view=grid_view,
+        field_options={str(field_1.id): {"width": 150}, field_2.id: {"width": 250}},
+    )
+    options = grid_view.get_field_options()
+    assert options.count() == 2
+
+    TrashHandler.trash(user, table.database.group, table.database, field_1)
+
+    options = grid_view.get_field_options()
+    assert options.count() == 1
+
+    with pytest.raises(UnrelatedFieldError):
+        ViewHandler().update_grid_view_field_options(
+            user=user,
+            grid_view=grid_view,
+            field_options={
+                field_1.id: {"width": 150},
+            },
+        )
+
+
 @pytest.mark.django_db
 @patch("baserow.contrib.database.views.signals.grid_view_field_options_updated.send")
 def test_update_grid_view_field_options(send_mock, data_fixture):

backend/tests/baserow/contrib/database/ws/test_ws_fields_signals.py

@@ -3,6 +3,7 @@ import pytest
 from unittest.mock import patch
 
 from baserow.contrib.database.fields.handler import FieldHandler
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db(transaction=True)
@@ -21,6 +22,20 @@ def test_field_created(mock_broadcast_to_channel_group, data_fixture):
     assert args[0][1]["field"]["id"] == field.id
 
 
+@pytest.mark.django_db(transaction=True)
+@patch("baserow.ws.registries.broadcast_to_channel_group")
+def test_field_restored(mock_broadcast_to_channel_group, data_fixture):
+    user = data_fixture.create_user()
+    field = data_fixture.create_text_field(user=user)
+    FieldHandler().delete_field(user, field)
+    TrashHandler.restore_item(user, "field", field.id)
+
+    args = mock_broadcast_to_channel_group.delay.call_args
+    assert args[0][0] == f"table-{field.table.id}"
+    assert args[0][1]["type"] == "field_restored"
+    assert args[0][1]["field"]["id"] == field.id, args[0]
+
+
 @pytest.mark.django_db(transaction=True)
 @patch("baserow.ws.registries.broadcast_to_channel_group")
 def test_field_updated(mock_broadcast_to_channel_group, data_fixture):

backend/tests/baserow/core/test_core_handler.py

@@ -1,16 +1,14 @@
 import os
+from io import BytesIO
 from pathlib import Path
 from unittest.mock import patch
 
-from io import BytesIO
-
 import pytest
 from django.conf import settings
-from django.db import connection
 from django.core.files.storage import FileSystemStorage
 from itsdangerous.exc import BadSignature
 
-from baserow.contrib.database.models import Database, Table
+from baserow.contrib.database.models import Database
 from baserow.core.exceptions import (
     UserNotInGroup,
     ApplicationTypeDoesNotExist,
@@ -38,6 +36,7 @@ from baserow.core.models import (
     TemplateCategory,
     GROUP_USER_PERMISSION_ADMIN,
 )
+from baserow.core.trash.handler import TrashHandler
 from baserow.core.user_files.models import UserFile
 
 
@@ -199,6 +198,36 @@ def test_create_group(send_mock, data_fixture):
     assert GroupUser.objects.all().count() == 2
 
 
+@pytest.mark.django_db
+@patch("baserow.core.signals.group_restored.send")
+def test_restore_group(group_restored_mock, data_fixture):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(name="Test group", user=user)
+
+    handler = CoreHandler()
+
+    handler.delete_group(user, group)
+
+    assert Group.objects.count() == 0
+
+    TrashHandler.restore_item(user, "group", group.id)
+
+    group_restored_mock.assert_called_once()
+    assert group_restored_mock.call_args[1]["user"] is None
+    assert (
+        group_restored_mock.call_args[1]["group_user"].id
+        == group.groupuser_set.get(user=user).id
+    )
+
+    group = Group.objects.all().first()
+    user_group = GroupUser.objects.all().first()
+
+    assert group.name == "Test group"
+    assert user_group.user == user
+    assert user_group.group == group
+    assert user_group.permissions == GROUP_USER_PERMISSION_ADMIN
+
+
 @pytest.mark.django_db
 @patch("baserow.core.signals.group_updated.send")
 def test_update_group(send_mock, data_fixture):
@@ -230,7 +259,7 @@ def test_delete_group(send_mock, data_fixture):
     user = data_fixture.create_user()
     group_1 = data_fixture.create_group(user=user)
     database = data_fixture.create_database_application(group=group_1)
-    table = data_fixture.create_database_table(database=database)
+    data_fixture.create_database_table(database=database)
     data_fixture.create_group(user=user)
     user_2 = data_fixture.create_user()
     group_3 = data_fixture.create_group(user=user_2)
@@ -238,25 +267,28 @@ def test_delete_group(send_mock, data_fixture):
     handler = CoreHandler()
     handler.delete_group(user, group_1)
 
+    assert group_1.trashed
+
     send_mock.assert_called_once()
     assert send_mock.call_args[1]["group"].id == group_1.id
     assert send_mock.call_args[1]["user"].id == user.id
     assert len(send_mock.call_args[1]["group_users"]) == 1
     assert send_mock.call_args[1]["group_users"][0].id == user.id
 
-    assert Database.objects.all().count() == 0
-    assert Table.objects.all().count() == 0
-    assert f"database_table_{table.id}" not in connection.introspection.table_names()
-    assert Group.objects.all().count() == 2
-    assert GroupUser.objects.all().count() == 2
+    assert Group.objects.count() == 2
+    assert GroupUser.objects.count() == 2
+    assert Group.trash.count() == 1
+    assert GroupUser.trash.count() == 1
 
     with pytest.raises(UserNotInGroup):
         handler.delete_group(user, group_3)
 
     handler.delete_group(user_2, group_3)
 
-    assert Group.objects.all().count() == 1
-    assert GroupUser.objects.all().count() == 1
+    assert Group.objects.count() == 1
+    assert GroupUser.objects.count() == 1
+    assert Group.trash.count() == 2
+    assert GroupUser.trash.count() == 2
 
     with pytest.raises(ValueError):
         handler.delete_group(user=user_2, group=object())
@@ -671,7 +703,6 @@ def test_create_database_application(send_mock, data_fixture):
     send_mock.assert_called_once()
     assert send_mock.call_args[1]["application"].id == database.id
     assert send_mock.call_args[1]["user"].id == user.id
-    assert send_mock.call_args[1]["type_name"] == "database"
 
     with pytest.raises(UserNotInGroup):
         handler.create_application(
@@ -776,7 +807,7 @@ def test_delete_database_application(send_mock, data_fixture):
     user_2 = data_fixture.create_user()
     group = data_fixture.create_group(user=user)
     database = data_fixture.create_database_application(group=group)
-    table = data_fixture.create_database_table(database=database)
+    data_fixture.create_database_table(database=database)
 
     handler = CoreHandler()
 
@@ -788,9 +819,11 @@ def test_delete_database_application(send_mock, data_fixture):
 
     handler.delete_application(user=user, application=database)
 
+    database.refresh_from_db()
+    assert database.trashed
+
     assert Database.objects.all().count() == 0
-    assert Table.objects.all().count() == 0
-    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+    assert Database.trash.all().count() == 1
 
     send_mock.assert_called_once()
     assert send_mock.call_args[1]["application_id"] == database.id
@@ -970,7 +1003,6 @@ def test_install_template(send_mock, tmpdir, data_fixture):
     send_mock.assert_called_once()
     assert send_mock.call_args[1]["application"].id == applications[0].id
     assert send_mock.call_args[1]["user"].id == user.id
-    assert send_mock.call_args[1]["type_name"] == "database"
 
     # Because the `example-template.json` has a file field that contains the hello
     # world file, we expect it to exist after syncing the templates.
@@ -982,3 +1014,28 @@ def test_install_template(send_mock, tmpdir, data_fixture):
     assert file_path.open().read() == "Hello World"
 
     settings.APPLICATION_TEMPLATES_DIR = old_templates
+
+
+@pytest.mark.django_db
+@patch("baserow.core.signals.application_created.send")
+def test_restore_application(application_created_mock, data_fixture):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(name="Test group", user=user)
+    database = data_fixture.create_database_application(user=user, group=group)
+
+    handler = CoreHandler()
+
+    handler.delete_application(user, application=database)
+
+    assert Application.objects.count() == 0
+
+    TrashHandler.restore_item(user, "application", database.id)
+
+    application_created_mock.assert_called_once()
+    assert application_created_mock.call_args[1]["application"].id == database.id
+    assert application_created_mock.call_args[1]["user"] is None
+
+    restored_app = Application.objects.all().first()
+
+    assert restored_app.name == database.name
+    assert restored_app.id == database.id

backend/tests/baserow/core/test_core_managers.py

@@ -1,25 +0,0 @@
-import pytest
-
-from baserow.core.models import Group
-
-
-@pytest.mark.django_db
-def test_groups_of_user(data_fixture):
-    user_1 = data_fixture.create_user()
-    user_group_1 = data_fixture.create_user_group(user=user_1, order=1)
-    user_group_2 = data_fixture.create_user_group(user=user_1, order=2)
-    user_group_3 = data_fixture.create_user_group(user=user_1, order=0)
-
-    user_2 = data_fixture.create_user()
-    user_group_4 = data_fixture.create_user_group(user=user_2, order=0)
-
-    groups_user_1 = Group.objects.of_user(user=user_1)
-    assert len(groups_user_1) == 3
-
-    assert groups_user_1[0].id == user_group_3.group.id
-    assert groups_user_1[1].id == user_group_1.group.id
-    assert groups_user_1[2].id == user_group_2.group.id
-
-    groups_user_2 = Group.objects.of_user(user=user_2)
-    assert len(groups_user_2) == 1
-    assert groups_user_2[0].id == user_group_4.group.id

backend/tests/baserow/core/trash/test_trash_handler.py

@@ -0,0 +1,435 @@
+import pytest
+from django.db import connection
+from django.utils import timezone
+from freezegun import freeze_time
+
+from baserow.contrib.database.fields.models import Field
+from baserow.contrib.database.rows.handler import RowHandler
+from baserow.contrib.database.table.models import Table
+from baserow.core.exceptions import GroupDoesNotExist, ApplicationDoesNotExist
+from baserow.core.models import Group, Application
+from baserow.core.models import TrashEntry
+from baserow.core.trash.exceptions import CannotRestoreChildBeforeParent
+from baserow.core.trash.handler import TrashHandler, _get_trash_entry
+
+
+@pytest.mark.django_db
+def test_trashing_an_item_creates_a_trash_entry_in_the_db_and_marks_it_as_trashed(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+    assert not group_to_delete.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+    assert group_to_delete.trashed
+    trash_entry = TrashEntry.objects.get(
+        trash_item_id=group_to_delete.id, trash_item_type="group"
+    )
+    assert trash_entry.trashed_at.isoformat() == "2020-01-01T12:00:00+00:00"
+    assert Group.objects.count() == 0
+    assert Group.trash.count() == 1
+
+
+@pytest.mark.django_db
+def test_restoring_a_trashed_item_unmarks_it_as_trashed_and_deletes_the_entry(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+    TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+    assert group_to_delete.trashed
+    assert TrashEntry.objects.count() == 1
+
+    TrashHandler.restore_item(user, "group", group_to_delete.id)
+
+    group_to_delete.refresh_from_db()
+    assert not group_to_delete.trashed
+    assert TrashEntry.objects.count() == 0
+    assert Group.trash.count() == 0
+    assert Group.objects.count() == 1
+
+
+@pytest.mark.django_db
+def test_a_trash_entry_older_than_setting_gets_marked_for_permanent_deletion(
+    data_fixture, settings
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    trashed_at = timezone.now()
+    half_time = timezone.timedelta(
+        hours=settings.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED / 2
+    )
+    plus_one_hour_over = timezone.timedelta(
+        hours=settings.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED + 1
+    )
+    with freeze_time(trashed_at):
+        TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+
+    entry = _get_trash_entry(user, "group", None, group_to_delete.id)
+    assert not entry.should_be_permanently_deleted
+
+    datetime_when_trash_item_should_still_be_kept = trashed_at + half_time
+    with freeze_time(datetime_when_trash_item_should_still_be_kept):
+        TrashHandler.mark_old_trash_for_permanent_deletion()
+
+    entry.refresh_from_db()
+    assert not entry.should_be_permanently_deleted
+
+    datetime_when_trash_item_old_enough_to_be_deleted = trashed_at + plus_one_hour_over
+    with freeze_time(datetime_when_trash_item_old_enough_to_be_deleted):
+        TrashHandler.mark_old_trash_for_permanent_deletion()
+
+    entry.refresh_from_db()
+    assert entry.should_be_permanently_deleted
+
+
+@pytest.mark.django_db
+def test_a_trash_entry_marked_for_permanent_deletion_gets_deleted_by_task(
+    data_fixture, settings
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+
+    trashed_at = timezone.now()
+    plus_one_hour_over = timezone.timedelta(
+        hours=settings.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED + 1
+    )
+    with freeze_time(trashed_at):
+        TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+
+    TrashHandler.permanently_delete_marked_trash()
+    assert Group.trash.count() == 1
+
+    datetime_when_trash_item_old_enough_to_be_deleted = trashed_at + plus_one_hour_over
+    with freeze_time(datetime_when_trash_item_old_enough_to_be_deleted):
+        TrashHandler.mark_old_trash_for_permanent_deletion()
+
+    TrashHandler.permanently_delete_marked_trash()
+    assert Group.objects.count() == 0
+
+
+@pytest.mark.django_db
+def test_a_group_marked_for_perm_deletion_raises_a_404_when_asked_for_trash_contents(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+    assert not group_to_delete.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+    trash_entry = TrashEntry.objects.get(
+        trash_item_id=group_to_delete.id, trash_item_type="group"
+    )
+    trash_entry.should_be_permanently_deleted = True
+    trash_entry.save()
+
+    with pytest.raises(GroupDoesNotExist):
+        TrashHandler.get_trash_contents(user, group_to_delete.id, None)
+
+
+@pytest.mark.django_db
+def test_a_group_marked_for_perm_deletion_no_longer_shows_up_in_trash_structure(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group_to_delete = data_fixture.create_group(user=user)
+    assert not group_to_delete.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group_to_delete, None, group_to_delete)
+    trash_entry = TrashEntry.objects.get(
+        trash_item_id=group_to_delete.id, trash_item_type="group"
+    )
+    trash_entry.should_be_permanently_deleted = True
+    trash_entry.save()
+
+    assert len(TrashHandler.get_trash_structure(user)["groups"]) == 0
+
+
+@pytest.mark.django_db
+def test_an_app_marked_for_perm_deletion_raises_a_404_when_asked_for_trash_contents(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    trashed_database = data_fixture.create_database_application(user=user, group=group)
+    assert not trashed_database.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, trashed_database, trashed_database)
+    trash_entry = TrashEntry.objects.get(
+        trash_item_id=trashed_database.id, trash_item_type="application"
+    )
+    trash_entry.should_be_permanently_deleted = True
+    trash_entry.save()
+
+    with pytest.raises(ApplicationDoesNotExist):
+        TrashHandler.get_trash_contents(user, group.id, trashed_database.id)
+
+
+@pytest.mark.django_db
+def test_a_trashed_app_shows_up_in_trash_structure(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    trashed_database = data_fixture.create_database_application(user=user, group=group)
+    assert not trashed_database.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, trashed_database, trashed_database)
+
+    structure = TrashHandler.get_trash_structure(user)
+    applications_qs = structure["groups"][0]["applications"]
+    assert applications_qs.count() == 1
+    assert applications_qs.get().trashed
+
+
+@pytest.mark.django_db
+def test_an_app_marked_for_perm_deletion_no_longer_shows_up_in_trash_structure(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    trashed_database = data_fixture.create_database_application(user=user, group=group)
+    assert not trashed_database.trashed
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, trashed_database, trashed_database)
+    trash_entry = TrashEntry.objects.get(
+        trash_item_id=trashed_database.id, trash_item_type="application"
+    )
+    trash_entry.should_be_permanently_deleted = True
+    trash_entry.save()
+
+    for group in TrashHandler.get_trash_structure(user)["groups"]:
+        assert group["applications"].count() == 0
+
+
+@pytest.mark.django_db
+def test_perm_deleting_a_parent_with_a_trashed_child_also_cleans_up_the_child_entry(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    database = data_fixture.create_database_application(user=user, group=group)
+    table = data_fixture.create_database_table(database=database)
+    field = data_fixture.create_text_field(user=user, table=table)
+    table_model = table.get_model()
+    row = table_model.objects.create(**{f"field_{field.id}": "Test"})
+
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, database, row, parent_id=table.id)
+        TrashHandler.trash(user, group, database, field)
+        TrashHandler.trash(user, group, database, table)
+        TrashHandler.trash(user, group, database, database)
+        TrashHandler.trash(user, group, None, group)
+
+    TrashHandler.empty(user, group.id, None)
+
+    assert TrashEntry.objects.count() == 5
+
+    TrashHandler.permanently_delete_marked_trash()
+
+    assert TrashEntry.objects.count() == 0
+    assert Group.objects_and_trash.count() == 0
+    assert Application.objects_and_trash.count() == 0
+    assert Table.objects_and_trash.count() == 0
+    assert Field.objects_and_trash.count() == 0
+    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+
+
+@pytest.mark.django_db
+def test_perm_deleting_a_table_with_a_trashed_row_also_cleans_up_the_row_entry(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    database = data_fixture.create_database_application(user=user, group=group)
+    table = data_fixture.create_database_table(database=database)
+    field = data_fixture.create_text_field(user=user, table=table)
+    table_model = table.get_model()
+    row = table_model.objects.create(**{f"field_{field.id}": "Test"})
+
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, database, database)
+        TrashHandler.trash(user, group, database, row, parent_id=table.id)
+        TrashHandler.trash(user, group, database, table)
+
+    TrashHandler.empty(user, group.id, database.id)
+
+    assert TrashEntry.objects.count() == 3
+
+    TrashHandler.permanently_delete_marked_trash()
+
+    assert TrashEntry.objects.count() == 0
+    assert Table.objects_and_trash.count() == 0
+    assert Field.objects_and_trash.count() == 0
+    assert Application.objects_and_trash.count() == 0
+    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+
+
+@pytest.mark.django_db
+def test_trash_contents_are_ordered_from_newest_to_oldest_entries(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    trashed_database = data_fixture.create_database_application(user=user, group=group)
+
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, group, trashed_database, trashed_database)
+    with freeze_time("2020-01-01 12:02"):
+        TrashHandler.trash(user, group, None, group)
+
+    contents = TrashHandler.get_trash_contents(user, group.id, None)
+
+    assert contents[0].trash_item_type == "group"
+    assert contents[0].trash_item_id == group.id
+    assert contents[0].trashed_at.isoformat() == "2020-01-01T12:02:00+00:00"
+
+    assert contents[1].trash_item_type == "application"
+    assert contents[1].trash_item_id == trashed_database.id
+    assert contents[1].trashed_at.isoformat() == "2020-01-01T12:00:00+00:00"
+
+
+@pytest.mark.django_db
+def test_perm_deleting_one_group_should_not_effect_another_trashed_group(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    trashed_group = data_fixture.create_group(user=user)
+    other_trashed_group = data_fixture.create_group(user=user)
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, trashed_group, None, trashed_group)
+        TrashHandler.trash(user, other_trashed_group, None, other_trashed_group)
+
+    # Only mark one for deletion
+    parent_trash_entry = TrashEntry.objects.get(
+        trash_item_id=trashed_group.id, trash_item_type="group"
+    )
+    parent_trash_entry.should_be_permanently_deleted = True
+    parent_trash_entry.save()
+
+    assert TrashEntry.objects.count() == 2
+    assert TrashEntry.objects.filter(should_be_permanently_deleted=True).count() == 1
+    assert Group.objects_and_trash.count() == 2
+
+    TrashHandler.permanently_delete_marked_trash()
+
+    assert TrashEntry.objects.count() == 1
+    assert Group.objects_and_trash.count() == 1
+
+
+@pytest.mark.django_db
+def test_deleting_a_user_who_trashed_items_should_still_leave_those_items_trashed(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    trashed_group = data_fixture.create_group(user=user)
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(user, trashed_group, None, trashed_group)
+
+    assert TrashEntry.objects.count() == 1
+    assert Group.objects_and_trash.count() == 1
+
+    user.delete()
+
+    assert TrashEntry.objects.count() == 1
+    assert Group.objects_and_trash.count() == 1
+
+
+@pytest.mark.django_db
+def test_trashing_two_rows_in_different_tables_works_as_expected(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    table_1 = data_fixture.create_database_table(name="Car", user=user)
+    table_2 = data_fixture.create_database_table(name="Other Cars", user=user)
+    group = data_fixture.create_group(user=user)
+    name_field = data_fixture.create_text_field(
+        table=table_1, name="Name", text_default="Test"
+    )
+
+    handler = RowHandler()
+
+    row_in_table_1 = handler.create_row(
+        user=user,
+        table=table_1,
+        values={
+            name_field.id: "Tesla",
+        },
+    )
+    row_in_table_2 = handler.create_row(
+        user=user,
+        table=table_2,
+        values={
+            name_field.id: "Ford",
+        },
+    )
+    with freeze_time("2020-01-01 12:00"):
+        TrashHandler.trash(
+            user, group, table_1.database, row_in_table_1, parent_id=table_1.id
+        )
+        TrashHandler.trash(
+            user, group, table_2.database, row_in_table_2, parent_id=table_2.id
+        )
+
+    table_1_model = table_1.get_model()
+    table_2_model = table_2.get_model()
+
+    assert table_1_model.trash.count() == 1
+    assert table_1_model.objects.count() == 0
+
+    assert table_2_model.trash.count() == 1
+    assert table_2_model.objects.count() == 0
+
+    TrashHandler.restore_item(
+        user, "row", row_in_table_1.id, parent_trash_item_id=table_1.id
+    )
+
+    assert table_1_model.trash.count() == 0
+    assert table_1_model.objects.count() == 1
+
+    assert table_2_model.trash.count() == 1
+    assert table_2_model.objects.count() == 0
+
+
+@pytest.mark.django_db
+def test_cannot_restore_a_child_before_the_parent(
+    data_fixture,
+):
+    user = data_fixture.create_user()
+    table_1 = data_fixture.create_database_table(name="Car", user=user)
+    group = table_1.database.group
+    name_field = data_fixture.create_text_field(
+        table=table_1, name="Name", text_default="Test"
+    )
+
+    handler = RowHandler()
+
+    row_in_table_1 = handler.create_row(
+        user=user,
+        table=table_1,
+        values={
+            name_field.id: "Tesla",
+        },
+    )
+    TrashHandler.trash(
+        user, group, table_1.database, row_in_table_1, parent_id=table_1.id
+    )
+    TrashHandler.trash(user, group, table_1.database, table_1)
+
+    with pytest.raises(CannotRestoreChildBeforeParent):
+        TrashHandler.restore_item(
+            user, "row", row_in_table_1.id, parent_trash_item_id=table_1.id
+        )
+
+    TrashHandler.trash(user, group, table_1.database, table_1.database)
+    TrashHandler.trash(user, group, None, group)
+
+    with pytest.raises(CannotRestoreChildBeforeParent):
+        TrashHandler.restore_item(user, "application", table_1.database.id)
+
+    TrashHandler.restore_item(user, "group", group.id)
+
+    with pytest.raises(CannotRestoreChildBeforeParent):
+        TrashHandler.restore_item(user, "table", table_1.id)

backend/tests/baserow/core/trash/test_trash_types.py

@@ -0,0 +1,49 @@
+import pytest
+from django.db import connection
+
+from baserow.contrib.database.models import Database
+from baserow.contrib.database.table.models import Table
+from baserow.core.models import Group, GroupUser
+from baserow.core.trash.handler import TrashHandler
+from baserow.core.trash.trash_types import GroupTrashableItemType
+
+
+@pytest.mark.django_db
+def test_perm_delete_group(data_fixture):
+    user = data_fixture.create_user()
+    group_1 = data_fixture.create_group(user=user)
+    database = data_fixture.create_database_application(group=group_1)
+    table = data_fixture.create_database_table(database=database)
+    data_fixture.create_group(user=user)
+    user_2 = data_fixture.create_user()
+    group_3 = data_fixture.create_group(user=user_2)
+
+    handler = GroupTrashableItemType()
+    handler.permanently_delete_item(group_1)
+
+    assert Database.objects.all().count() == 0
+    assert Table.objects.all().count() == 0
+    assert f"database_table_{table.id}" not in connection.introspection.table_names()
+    assert Group.objects.all().count() == 2
+    assert GroupUser.objects.all().count() == 2
+
+    handler.permanently_delete_item(group_3)
+
+    assert Group.objects.all().count() == 1
+    assert GroupUser.objects.all().count() == 1
+
+
+@pytest.mark.django_db
+def test_perm_delete_application(data_fixture):
+    user = data_fixture.create_user()
+    group = data_fixture.create_group(user=user)
+    database = data_fixture.create_database_application(group=group)
+    table = data_fixture.create_database_table(database=database)
+
+    handler = TrashHandler()
+
+    handler.permanently_delete(database)
+
+    assert Database.objects.all().count() == 0
+    assert Table.objects.all().count() == 0
+    assert f"database_table_{table.id}" not in connection.introspection.table_names()

backend/tests/baserow/performance/test_trash_performance.py

@@ -0,0 +1,40 @@
+import pytest
+
+from baserow.contrib.database.management.commands.fill_table import fill_table
+from baserow.core.models import TrashEntry
+from baserow.core.trash.handler import TrashHandler
+from tests.test_utils import setup_interesting_test_table
+
+from pyinstrument import Profiler
+
+
+@pytest.mark.django_db
+@pytest.mark.slow
+# You must add --runslow -s to pytest to run this test, you can do this in intellij by
+# editing the run config for this test and adding --runslow -s to additional args.
+def test_deleting_many_of_rows_is_fast(data_fixture):
+
+    table, user, row = setup_interesting_test_table(data_fixture)
+    count = 1000
+    fill_table(count, table)
+
+    model = table.get_model()
+    for row in model.objects.all():
+        TrashHandler.trash(
+            user, table.database.group, table.database, row, parent_id=table.id
+        )
+
+    TrashEntry.objects.update(should_be_permanently_deleted=True)
+
+    assert model.objects.all().count() == 0
+    assert model.trash.all().count() == count + 2
+    assert TrashEntry.objects.count() == count + 2
+
+    profiler = Profiler()
+    profiler.start()
+    TrashHandler.permanently_delete_marked_trash()
+    profiler.stop()
+    # Add -s also the the additional args to see the profiling output!
+    # As of 22/06/2021 on a 5900X the profiler output showed 0.82 seconds to
+    # perm delete these 1000 rows.
+    print(profiler.output_text(unicode=True, color=True))

backend/tests/baserow/ws/test_ws_signals.py

@@ -1,8 +1,13 @@
-import pytest
-
 from unittest.mock import patch
 
+import pytest
+
 from baserow.core.handler import CoreHandler
+from baserow.core.models import (
+    GROUP_USER_PERMISSION_ADMIN,
+    GROUP_USER_PERMISSION_MEMBER,
+)
+from baserow.core.trash.handler import TrashHandler
 
 
 @pytest.mark.django_db(transaction=True)
@@ -18,6 +23,50 @@ def test_group_created(mock_broadcast_to_group, data_fixture):
     assert args[0][1]["group"]["id"] == group_user.group_id
 
 
+@pytest.mark.django_db(transaction=True)
+@patch("baserow.ws.signals.broadcast_to_users")
+def test_group_restored(mock_broadcast_to_users, data_fixture):
+    user = data_fixture.create_user()
+    member_user = data_fixture.create_user()
+    # This user should not be sent the restore signal
+    data_fixture.create_user()
+    group = data_fixture.create_group()
+    group_user = data_fixture.create_user_group(
+        user=user, group=group, permissions=GROUP_USER_PERMISSION_ADMIN
+    )
+    member_group_user = data_fixture.create_user_group(
+        user=member_user, group=group, permissions=GROUP_USER_PERMISSION_MEMBER
+    )
+    database = data_fixture.create_database_application(user=user, group=group)
+    TrashHandler.trash(user, group, None, group)
+
+    TrashHandler.restore_item(user, "group", group.id)
+
+    args = mock_broadcast_to_users.delay.call_args_list
+    assert len(args) == 2
+    member_call = args[1][0]
+    admin_call = args[0][0]
+    assert member_call[0] == [member_user.id]
+    assert member_call[1]["type"] == "group_restored"
+    assert member_call[1]["group"]["id"] == member_group_user.group_id
+    assert member_call[1]["group"]["permissions"] == "MEMBER"
+    expected_group_json = {
+        "id": database.id,
+        "name": database.name,
+        "order": 0,
+        "type": "database",
+        "tables": [],
+        "group": {"id": group.id, "name": group.name},
+    }
+    assert member_call[1]["applications"] == [expected_group_json]
+    assert admin_call[0] == [user.id]
+    assert admin_call[1]["type"] == "group_restored"
+    assert admin_call[1]["group"]["id"] == group_user.group_id
+    assert admin_call[1]["group"]["permissions"] == "ADMIN"
+    assert admin_call[1]["group"]["id"] == group_user.group_id
+    assert admin_call[1]["applications"] == [expected_group_json]
+
+
 @pytest.mark.django_db(transaction=True)
 @patch("baserow.ws.signals.broadcast_to_group")
 def test_group_updated(mock_broadcast_to_group, data_fixture):

backend/tests/test_utils.py

@@ -185,4 +185,4 @@ def setup_interesting_test_table(data_fixture):
     getattr(row, f"field_{name_to_field_id['file_link_row']}").add(
         linked_row_7.id, linked_row_8.id
     )
-    return table, user
+    return table, user, row

changelog.md

@@ -3,6 +3,8 @@
 ## Unreleased
 
 * Made it possible to list table field meta-data with a token.
+* Add trash where deleted apps, groups, tables, fields and rows can be restored 
+  deletion.
 * Fix the create group invite endpoint failing when no message provided.
 * Single select options can now be ordered by drag and drop. 
 * Added before and after date filters.

docs/getting-started/introduction.md

@@ -133,3 +133,5 @@ are accepted.
 * `EMAIL_SMTP_PORT` (default `25`): The port of the SMTP server.
 * `EMAIL_SMTP_USER` (default ``): The username for the SMTP server.
 * `EMAIL_SMTP_PASSWORD` (default ``): The password of the SMTP server.
+* `HOURS_UNTIL_TRASH_PERMANENTLY_DELETED` (default 72): The number of hours to keep 
+  trashed items until they are permanently deleted.

premium/backend/src/baserow_premium/admin/groups/handler.py

@@ -1,6 +1,6 @@
-from baserow.core.handler import CoreHandler
-from baserow.core.signals import group_deleted
 from baserow.core.exceptions import IsNotAdminError
+from baserow.core.signals import group_deleted
+from baserow.core.trash.handler import TrashHandler
 from baserow_premium.admin.groups.exceptions import CannotDeleteATemplateGroupError
 
 
@@ -27,7 +27,7 @@ class GroupsAdminHandler:
         group_id = group.id
         group_users = list(group.users.all())
 
-        CoreHandler()._delete_group(group)
+        TrashHandler.permanently_delete(group)
 
         group_deleted.send(
             self, group_id=group_id, group=group, group_users=group_users

premium/backend/tests/baserow_premium/export/test_premium_export_types.py

@@ -267,7 +267,7 @@ def strip_indents_and_newlines(xml):
 
 
 def run_export_over_interesting_test_table(data_fixture, storage_mock, options):
-    table, user = setup_interesting_test_table(data_fixture)
+    table, user, _ = setup_interesting_test_table(data_fixture)
     grid_view = data_fixture.create_grid_view(table=table)
     job, contents = run_export_job_with_mock_storage(
         table, grid_view, storage_mock, user, options

web-frontend/modules/core/assets/scss/components/all.scss

@@ -65,3 +65,6 @@
 @import 'paginator';
 @import 'sortable';
 @import 'export';
+@import 'trash';
+@import 'trash_entry';
+@import 'infinite_scroll';

web-frontend/modules/core/assets/scss/components/infinite_scroll.scss

@@ -0,0 +1,5 @@
+.infinite-scroll {
+  @include absolute(0, 0, 0, 0);
+
+  overflow-y: auto;
+}

web-frontend/modules/core/assets/scss/components/modal.scss

@@ -32,28 +32,47 @@
     padding: 0;
   }
 
+  &.modal__box--full-height {
+    height: calc(100% - 80px);
+  }
+
   &.modal__box--small {
     max-width: 520px;
   }
 
+  &.modal__box--tiny {
+    max-width: 320px;
+    padding: 15px;
+  }
+
   .box__title {
     margin-top: 0;
   }
 }
 
 .modal__box-sidebar {
+  position: relative;
   flex: 0 0 200px;
   background-color: $color-neutral-50;
   border-right: 1px solid $color-neutral-200;
   border-top-left-radius: 6px;
   border-bottom-left-radius: 6px;
+
+  .modal__box--full-height & {
+    overflow-y: auto;
+  }
 }
 
 .modal__box-content {
+  position: relative;
   width: 100%;
   padding: 32px 40px;
   min-width: 0;
   flex: 1;
+
+  .modal__box--full-height & {
+    overflow-y: auto;
+  }
 }
 
 .modal__close {

web-frontend/modules/core/assets/scss/components/modal_sidebar.scss

@@ -5,6 +5,11 @@
 }
 
 .modal-sidebar__head-icon {
+  flex: 0 0 32px;
+  margin-right: 16px;
+}
+
+.modal-sidebar__head-initials-icon {
   flex: 0 0 32px;
   border-radius: 100%;
   margin-right: 16px;
@@ -19,6 +24,17 @@
   font-weight: 600;
 }
 
+.modal-sidebar__head-icon-and-name {
+  font-size: 14px;
+  font-weight: 600;
+  line-height: 140%;
+}
+
+.modal-sidebar__head-icon-and-name-icon {
+  margin-right: 10px;
+  font-size: 12px;
+}
+
 .modal-sidebar__nav {
   list-style: none;
   margin: 0;
@@ -30,6 +46,7 @@
 
   position: relative;
   display: block;
+  height: 42px;
   line-height: 42px;
   padding: 0 20px 0 50px;
   border-left: solid 4px transparent;

web-frontend/modules/core/assets/scss/components/notifications.scss

@@ -1,7 +1,40 @@
-.notifications {
+.top-right-notifications {
   position: fixed;
   top: 0;
   right: 30px;
   width: 320px;
   z-index: $z-index-notifications;
 }
+
+.bottom-right-notifications {
+  display: flex;
+  flex-direction: column-reverse;
+  align-items: flex-end;
+  position: fixed;
+  bottom: 10px;
+  right: 30px;
+  z-index: $z-index-notifications;
+}
+
+.undo-delete-notification {
+  margin: 5px;
+  box-shadow: $color-primary-200;
+
+  &.undo-delete-notification--pulsing {
+    animation: pulse 1s 2;
+  }
+}
+
+@keyframes pulse {
+  0% {
+    box-shadow: 0 0 0 0 $color-primary-400;
+  }
+
+  70% {
+    box-shadow: 0 0 0 5px rgba(0, 0, 0, 0);
+  }
+
+  100% {
+    box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
+  }
+}

web-frontend/modules/core/assets/scss/components/trash.scss

@@ -0,0 +1,155 @@
+.trash-sidebar__groups {
+  list-style: none;
+  margin: 0;
+  padding: 0 0 20px 0;
+}
+
+.trash-sidebar__group {
+  margin-bottom: 4px;
+}
+
+.trash-sidebar__group-link {
+  @extend %ellipsis;
+
+  position: relative;
+  display: block;
+  padding: 0 16px 0 32px;
+  line-height: 33px;
+  font-size: 14px;
+  color: $color-primary-900;
+  border-left: solid 3px transparent;
+
+  &:hover {
+    text-decoration: none;
+    background-color: $color-neutral-200;
+  }
+
+  .trash-sidebar__group--active & {
+    background-color: $color-neutral-200;
+    border-left-color: $color-primary-500;
+  }
+
+  .trash-sidebar__group--trashed & {
+    text-decoration-line: line-through;
+  }
+
+  &::before {
+    @extend .fas;
+    @extend .fa-fw;
+
+    @include absolute(50%, auto, auto, 10px);
+
+    content: fa-content($fa-var-caret-right);
+    color: $color-primary-900;
+    font-size: 14px;
+    line-height: 12px;
+    margin-top: -6px;
+
+    .trash-sidebar__group--active & {
+      content: fa-content($fa-var-caret-down);
+    }
+  }
+}
+
+.trash-sidebar__applications {
+  display: none;
+  list-style: none;
+  margin: 0;
+  padding: 0;
+
+  .trash-sidebar__group--active &,
+  .trash-sidebar__group--open & {
+    display: block;
+  }
+}
+
+.trash-sidebar__application {
+  margin: 4px 0;
+}
+
+.trash-sidebar__application-link {
+  @extend %ellipsis;
+
+  display: block;
+  line-height: 33px;
+  font-size: 13px;
+  padding: 0 20px 0 28px;
+  color: $color-primary-900;
+  border-left: solid 3px transparent;
+
+  &:hover {
+    background-color: $color-neutral-200;
+    text-decoration: none;
+  }
+
+  .trash-sidebar__application--active & {
+    background-color: $color-neutral-200;
+    border-left-color: $color-primary-500;
+  }
+
+  .trash-sidebar__application--trashed & {
+    text-decoration-line: line-through;
+  }
+}
+
+.trash__title {
+  display: flex;
+  align-items: flex-end;
+  width: 100%;
+  height: 74px;
+  padding-bottom: 20px;
+  margin-bottom: 20px;
+  border-bottom: solid 1px $color-neutral-200;
+  background-color: $white;
+}
+
+.trash__title-left {
+  width: 100%;
+  min-width: 0;
+  margin-right: 20px;
+}
+
+.trash__title-heading {
+  @extend %ellipsis;
+
+  font-size: 22px;
+  font-weight: bold;
+  margin-bottom: 8px;
+}
+
+.trash__title-description {
+  @extend %ellipsis;
+
+  font-size: 14px;
+  color: $color-neutral-500;
+}
+
+.trash__title-right {
+  flex: 0 0;
+}
+
+.trash__empty {
+  text-align: center;
+  margin: 60px 0 30px 0;
+}
+
+.trash__empty-icon {
+  font-size: 30px;
+  color: $color-primary-500;
+  margin-bottom: 30px;
+}
+
+.trash__empty-text {
+  font-size: 14px;
+  color: $color-neutral-500;
+}
+
+.trash__entries {
+  @include absolute(106px, 0, 0, 0);
+}
+
+.trash__entries-loading-wrapper {
+  display: flex;
+  justify-content: center;
+  padding: 20px 0;
+}

web-frontend/modules/core/assets/scss/components/trash_entry.scss

@@ -0,0 +1,98 @@
+.trash-entry {
+  display: flex;
+  align-items: flex-start;
+  padding: 14px 40px;
+  background-color: $white;
+
+  &:first-child {
+    padding-top: 28px;
+  }
+
+  &:last-child {
+    padding-bottom: 28px;
+  }
+
+  &.trash-entry--disabled {
+    opacity: 0.4;
+  }
+}
+
+.trash-entry__initials {
+  flex: 0 0 36px;
+  margin-right: 16px;
+  border-radius: 100%;
+  background-color: $color-primary-500;
+  color: $white;
+  font-weight: 700;
+  font-size: 15px;
+
+  @include center-text(36px, 13px);
+}
+
+.trash-entry__content {
+  min-width: 0;
+  width: 100%;
+  display: flex;
+  flex-direction: column;
+  align-items: flex-start;
+  line-height: normal;
+}
+
+.trash-entry__name {
+  @extend %ellipsis;
+
+  font-size: 13px;
+  color: $color-primary-900;
+  margin-bottom: 6px;
+  max-width: 100%;
+}
+
+.trash-entry__deleted-at-display {
+  @extend %ellipsis;
+
+  font-size: 12px;
+  color: $color-neutral-500;
+  max-width: 100%;
+}
+
+.trash-entry__extra-description {
+  font-size: 12px;
+  background-color: $color-primary-100;
+  border-radius: 3px;
+  padding: 4px;
+  margin-top: 6px;
+
+  &:not(:last-child) {
+    margin-right: 6px;
+  }
+}
+
+.trash-entry__actions {
+  flex: 0 0;
+  display: flex;
+  flex-direction: column;
+  align-items: flex-start;
+  justify-content: center;
+  margin-left: 20px;
+}
+
+.trash-entry__action {
+  position: relative;
+  font-size: 13px;
+  width: 48px;
+
+  &:not(:last-child) {
+    margin-right: 8px;
+  }
+
+  &.trash-entry__action--loading {
+    cursor: inherit;
+
+    &::after {
+      content: '';
+      margin-left: 17px;
+
+      @include loading(13px);
+    }
+  }
+}

web-frontend/modules/core/assets/scss/helpers.scss

@@ -62,7 +62,11 @@
 }
 
 .margin-right-1 {
-  margin-right: 8px;
+  margin-right: 8px !important;
+}
+
+.margin-right-2 {
+  margin-right: 16px !important;
 }
 
 .resizing-horizontal {

web-frontend/modules/core/components/Modal.vue

@@ -8,14 +8,13 @@
     <div
       class="modal__box"
       :class="{
+        'modal__box--full-height': fullHeight,
         'modal__box--with-sidebar': sidebar,
         'modal__box--full-screen': fullScreen,
         'modal__box--small': small,
+        'modal__box--tiny': tiny,
       }"
     >
-      <a v-if="closeButton" class="modal__close" @click="hide()">
-        <i class="fas fa-times"></i>
-      </a>
       <template v-if="sidebar">
         <div class="modal__box-sidebar">
           <slot name="sidebar"></slot>
@@ -27,6 +26,9 @@
       <template v-if="!sidebar">
         <slot></slot>
       </template>
+      <a v-if="closeButton" class="modal__close" @click="hide()">
+        <i class="fas fa-times"></i>
+      </a>
     </div>
   </div>
 </template>
@@ -53,11 +55,21 @@ export default {
       default: false,
       required: false,
     },
+    tiny: {
+      type: Boolean,
+      default: false,
+      required: false,
+    },
     closeButton: {
       type: Boolean,
       default: true,
       required: false,
     },
+    fullHeight: {
+      type: Boolean,
+      default: false,
+      required: false,
+    },
   },
 }
 </script>

web-frontend/modules/core/components/group/DeleteGroupModal.vue

@@ -1,106 +0,0 @@
-<template>
-  <Modal>
-    <h2 class="box__title">Delete {{ group.name }}</h2>
-    <Error :error="error"></Error>
-    <div>
-      <p>
-        Are you sure you want to delete the group
-        <strong>{{ group.name }}</strong
-        >?
-        <span v-if="applications.length > 0">
-          The following
-          <template v-if="applications.length == 1"
-            >application including its data is</template
-          >
-          <template v-else>applications including their data are</template>
-          going to be permanently deleted:</span
-        >
-      </p>
-      <div v-if="applications.length > 0" class="delete-section">
-        <div class="delete-section__label">
-          <div class="delete-section__label-icon">
-            <i class="fas fa-exclamation"></i>
-          </div>
-          Will also be permanently deleted
-        </div>
-        <ul class="delete-section__list">
-          <li v-for="application in applications" :key="application.id">
-            <i
-              class="delete-section__list-icon fas fa-database"
-              :class="'fa-' + application._.type.iconClass"
-            ></i>
-            {{ application.name }}
-            <small>{{ getApplicationDependentsText(application) }}</small>
-          </li>
-        </ul>
-      </div>
-      <div class="actions">
-        <div class="align-right">
-          <button
-            class="button button--large button--error"
-            :class="{ 'button--loading': loading }"
-            :disabled="loading"
-            @click="deleteGroup()"
-          >
-            Delete group
-          </button>
-        </div>
-      </div>
-    </div>
-  </Modal>
-</template>
-
-<script>
-import { mapGetters } from 'vuex'
-import modal from '@baserow/modules/core/mixins/modal'
-import error from '@baserow/modules/core/mixins/error'
-
-export default {
-  name: 'DeleteGroupModal',
-  mixins: [modal, error],
-  props: {
-    group: {
-      type: Object,
-      required: true,
-    },
-  },
-  data() {
-    return {
-      loading: false,
-    }
-  },
-  computed: {
-    ...mapGetters({
-      getAllOfGroup: 'application/getAllOfGroup',
-    }),
-    applications() {
-      return this.getAllOfGroup(this.group)
-    },
-  },
-  methods: {
-    async deleteGroup() {
-      this.hideError()
-      this.loading = true
-
-      try {
-        await this.$store.dispatch('group/delete', this.group)
-        this.hide()
-      } catch (error) {
-        this.handleError(error, 'application')
-      }
-
-      this.loading = false
-    },
-    getApplicationDependentsText(application) {
-      const dependents = this.$registry
-        .get('application', application.type)
-        .getDependents(application)
-      const names = this.$registry
-        .get('application', application.type)
-        .getDependentsName(application)
-      const name = dependents.length === 1 ? names[0] : names[1]
-      return `including ${dependents.length} ${name}`
-    },
-  },
-}
-</script>

web-frontend/modules/core/components/group/GroupContext.vue

@@ -15,7 +15,16 @@
         </a>
       </li>
       <li>
-        <a @click="$refs.deleteGroupModal.show()">
+        <a @click="showGroupTrashModal">
+          <i class="context__menu-icon fas fa-fw fa-recycle"></i>
+          View trash
+        </a>
+      </li>
+      <li>
+        <a
+          :class="{ 'context__menu-item--loading': loading }"
+          @click="deleteGroup"
+        >
           <i class="context__menu-icon fas fa-fw fa-trash"></i>
           Delete group
         </a>
@@ -25,18 +34,19 @@
       ref="groupMembersModal"
       :group="group"
     ></GroupMembersModal>
-    <DeleteGroupModal ref="deleteGroupModal" :group="group" />
+    <TrashModal ref="groupTrashModal" :initial-group="group"> </TrashModal>
   </Context>
 </template>
 
 <script>
-import DeleteGroupModal from '@baserow/modules/core/components/group/DeleteGroupModal'
 import GroupMembersModal from '@baserow/modules/core/components/group/GroupMembersModal'
 import context from '@baserow/modules/core/mixins/context'
+import { notifyIf } from '@baserow/modules/core/utils/error'
+import TrashModal from '@baserow/modules/core/components/trash/TrashModal'
 
 export default {
   name: 'GroupContext',
-  components: { DeleteGroupModal, GroupMembersModal },
+  components: { TrashModal, GroupMembersModal },
   mixins: [context],
   props: {
     group: {
@@ -44,10 +54,35 @@ export default {
       required: true,
     },
   },
+  data() {
+    return {
+      loading: false,
+    }
+  },
   methods: {
     showGroupMembersModal() {
       this.$refs.groupMembersModal.show()
     },
+    showGroupTrashModal() {
+      this.$refs.context.hide()
+      this.$refs.groupTrashModal.show()
+    },
+    async deleteGroup() {
+      this.loading = true
+
+      try {
+        await this.$store.dispatch('group/delete', this.group)
+        await this.$store.dispatch('notification/restore', {
+          trash_item_type: 'group',
+          trash_item_id: this.group.id,
+        })
+        this.hide()
+      } catch (error) {
+        notifyIf(error, 'application')
+      }
+
+      this.loading = false
+    },
   },
 }
 </script>

web-frontend/modules/core/components/infinite_scroll/InfiniteScroll.vue

@@ -0,0 +1,36 @@
+<template>
+  <section class="infinite-scroll" @scroll="handleScroll">
+    <slot />
+  </section>
+</template>
+
+<script>
+export default {
+  props: {
+    currentCount: {
+      type: Number,
+      required: true,
+    },
+    maxCount: {
+      type: Number,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      currentPage: 1,
+    }
+  },
+  methods: {
+    handleScroll({ target: { scrollTop, clientHeight, scrollHeight } }) {
+      if (scrollTop + clientHeight >= scrollHeight) this.loadNextPage()
+    },
+    loadNextPage() {
+      if (this.currentCount < this.maxCount) {
+        this.currentPage = this.currentPage + 1
+        this.$emit('load-next-page', this.currentPage)
+      }
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/notifications/Notifications.vue

@@ -1,14 +1,23 @@
 <template>
   <div class="notifications">
-    <ConnectingNotification v-if="connecting"></ConnectingNotification>
-    <FailedConnectingNotification
-      v-if="failedConnecting"
-    ></FailedConnectingNotification>
-    <Notification
-      v-for="notification in notifications"
-      :key="notification.id"
-      :notification="notification"
-    ></Notification>
+    <div class="top-right-notifications">
+      <ConnectingNotification v-if="connecting"></ConnectingNotification>
+      <FailedConnectingNotification
+        v-if="failedConnecting"
+      ></FailedConnectingNotification>
+      <Notification
+        v-for="notification in normalNotifications"
+        :key="notification.id"
+        :notification="notification"
+      ></Notification>
+    </div>
+    <div class="bottom-right-notifications">
+      <RestoreNotification
+        v-for="notification in restoreNotifications"
+        :key="notification.id"
+        :notification="notification"
+      ></RestoreNotification>
+    </div>
   </div>
 </template>
 
@@ -18,15 +27,23 @@ import { mapState } from 'vuex'
 import Notification from '@baserow/modules/core/components/notifications/Notification'
 import ConnectingNotification from '@baserow/modules/core/components/notifications/ConnectingNotification'
 import FailedConnectingNotification from '@baserow/modules/core/components/notifications/FailedConnectingNotification'
+import RestoreNotification from '@baserow/modules/core/components/notifications/RestoreNotification'
 
 export default {
   name: 'Notifications',
   components: {
+    RestoreNotification,
     Notification,
     ConnectingNotification,
     FailedConnectingNotification,
   },
   computed: {
+    restoreNotifications() {
+      return this.notifications.filter((n) => n.type === 'restore')
+    },
+    normalNotifications() {
+      return this.notifications.filter((n) => n.type !== 'restore')
+    },
     ...mapState({
       connecting: (state) => state.notification.connecting,
       failedConnecting: (state) => state.notification.failedConnecting,

web-frontend/modules/core/components/notifications/RestoreNotification.vue

@@ -0,0 +1,59 @@
+<template>
+  <button
+    class="button undo-delete-notification"
+    :disabled="loading"
+    :class="{
+      'button--loading': loading,
+      'undo-delete-notification--pulsing': pulsing,
+    }"
+    @click="restore"
+  >
+    <i class="button__icon fas fa-undo"> </i>
+    Restore deleted {{ notification.data.trash_item_type }}
+  </button>
+</template>
+
+<script>
+import TrashService from '@baserow/modules/core/services/trash'
+import { notifyIf } from '@baserow/modules/core/utils/error'
+
+export default {
+  name: 'RestoreNotification',
+  props: {
+    notification: {
+      type: Object,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      loading: false,
+      pulsing: true,
+    }
+  },
+  mounted() {
+    setTimeout(() => {
+      this.pulsing = false
+    }, 2000)
+    setTimeout(() => {
+      this.close()
+    }, 5000)
+  },
+  methods: {
+    close() {
+      this.$store.dispatch('notification/remove', this.notification)
+    },
+    async restore() {
+      this.loading = true
+      this.pulsing = false
+      try {
+        await TrashService(this.$client).restore(this.notification.data)
+      } catch (error) {
+        notifyIf(error, 'trash')
+      }
+      this.close()
+      this.loading = false
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/settings/SettingsModal.vue

@@ -2,7 +2,7 @@
   <Modal :sidebar="true">
     <template #sidebar>
       <div class="modal-sidebar__head">
-        <div class="modal-sidebar__head-icon">
+        <div class="modal-sidebar__head-initials-icon">
           {{ name | nameAbbreviation }}
         </div>
         <div class="modal-sidebar__head-name">Settings</div>

web-frontend/modules/core/components/sidebar/DeleteApplicationModal.vue

@@ -1,98 +0,0 @@
-<template>
-  <Modal>
-    <h2 class="box__title">Delete {{ application.name }}</h2>
-    <Error :error="error"></Error>
-    <div>
-      <p>
-        Are you sure you want to delete the
-        {{ application._.type.name | lowercase }}
-        <strong>{{ application.name }}</strong
-        >?
-        <span v-if="dependents.length > 0"
-          >The following {{ dependentsName }}
-          <template v-if="dependents.length === 1">is</template>
-          <template v-else>are</template>
-          also going to be permanently deleted:</span
-        >
-      </p>
-      <div v-if="dependents.length > 0" class="delete-section">
-        <div class="delete-section__label">
-          <div class="delete-section__label-icon">
-            <i class="fas fa-exclamation"></i>
-          </div>
-          Will also be permanently deleted
-        </div>
-        <ul class="delete-section__list">
-          <li v-for="dependent in dependents" :key="dependent.id">
-            <i
-              class="delete-section__list-icon fas fa-database"
-              :class="'fa-' + dependent.iconClass"
-            ></i>
-            {{ dependent.name }}
-          </li>
-        </ul>
-      </div>
-      <div class="actions">
-        <div class="align-right">
-          <button
-            class="button button--large button--error"
-            :class="{ 'button--loading': loading }"
-            :disabled="loading"
-            @click="deleteApplication()"
-          >
-            Delete {{ application._.type.name | lowercase }}
-          </button>
-        </div>
-      </div>
-    </div>
-  </Modal>
-</template>
-
-<script>
-import modal from '@baserow/modules/core/mixins/modal'
-import error from '@baserow/modules/core/mixins/error'
-
-export default {
-  name: 'DeleteApplicationModal',
-  mixins: [modal, error],
-  props: {
-    application: {
-      type: Object,
-      required: true,
-    },
-  },
-  data() {
-    return {
-      loading: false,
-    }
-  },
-  computed: {
-    dependentsName() {
-      const names = this.$registry
-        .get('application', this.application.type)
-        .getDependentsName(this.application)
-      return this.dependents.length === 1 ? names[0] : names[1]
-    },
-    dependents() {
-      return this.$registry
-        .get('application', this.application.type)
-        .getDependents(this.application)
-    },
-  },
-  methods: {
-    async deleteApplication() {
-      this.hideError()
-      this.loading = true
-
-      try {
-        await this.$store.dispatch('application/delete', this.application)
-        this.hide()
-      } catch (error) {
-        this.handleError(error, 'application')
-      }
-
-      this.loading = false
-    },
-  },
-}
-</script>

web-frontend/modules/core/components/sidebar/Sidebar.vue

@@ -69,6 +69,17 @@
               </nuxt-link>
             </div>
           </li>
+          <li class="tree__item">
+            <div class="tree__action sidebar__action">
+              <a class="tree__link" @click="$refs.trashModal.show()">
+                <div>
+                  <i class="tree__icon fas fa-trash"></i>
+                  <span class="sidebar__item-name">Trash</span>
+                </div>
+              </a>
+              <TrashModal ref="trashModal"></TrashModal>
+            </div>
+          </li>
           <li v-if="isStaff" class="tree__item">
             <div
               class="tree__action sidebar__action"
@@ -147,6 +158,7 @@
                   handle: '[data-sortable-handle]',
                 }"
                 :application="application"
+                :group="selectedGroup"
               ></component>
             </ul>
             <li class="sidebar__new-wrapper">
@@ -232,6 +244,7 @@ import CreateApplicationContext from '@baserow/modules/core/components/applicati
 import GroupsContext from '@baserow/modules/core/components/group/GroupsContext'
 import CreateGroupModal from '@baserow/modules/core/components/group/CreateGroupModal'
 import GroupMembersModal from '@baserow/modules/core/components/group/GroupMembersModal'
+import TrashModal from '@baserow/modules/core/components/trash/TrashModal'
 
 export default {
   name: 'Sidebar',
@@ -242,6 +255,7 @@ export default {
     GroupsContext,
     CreateGroupModal,
     GroupMembersModal,
+    TrashModal,
   },
   computed: {
     /**

web-frontend/modules/core/components/sidebar/SidebarApplication.vue

@@ -37,17 +37,28 @@
             </a>
           </li>
           <li>
-            <a @click="deleteApplication()">
+            <a @click="showApplicationTrashModal">
+              <i class="context__menu-icon fas fa-fw fa-recycle"></i>
+              View trash
+            </a>
+          </li>
+          <li>
+            <a
+              :class="{ 'context__menu-item--loading': deleteLoading }"
+              @click="deleteApplication()"
+            >
               <i class="context__menu-icon fas fa-fw fa-trash"></i>
               Delete {{ application._.type.name | lowercase }}
             </a>
           </li>
         </ul>
-        <DeleteApplicationModal
-          ref="deleteApplicationModal"
-          :application="application"
-        />
       </Context>
+      <TrashModal
+        ref="applicationTrashModal"
+        :initial-group="group"
+        :initial-application="application"
+      >
+      </TrashModal>
     </div>
     <slot name="body"></slot>
   </li>
@@ -55,16 +66,25 @@
 
 <script>
 import { notifyIf } from '@baserow/modules/core/utils/error'
-import DeleteApplicationModal from './DeleteApplicationModal'
+import TrashModal from '@baserow/modules/core/components/trash/TrashModal'
 
 export default {
   name: 'SidebarApplication',
-  components: { DeleteApplicationModal },
+  components: { TrashModal },
   props: {
     application: {
       type: Object,
       required: true,
     },
+    group: {
+      type: Object,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      deleteLoading: false,
+    }
   },
   methods: {
     setLoading(application, value) {
@@ -94,9 +114,24 @@ export default {
 
       this.setLoading(application, false)
     },
-    deleteApplication() {
+    async deleteApplication() {
+      this.deleteLoading = true
+
+      try {
+        await this.$store.dispatch('application/delete', this.application)
+        await this.$store.dispatch('notification/restore', {
+          trash_item_type: 'application',
+          trash_item_id: this.application.id,
+        })
+      } catch (error) {
+        notifyIf(error, 'application')
+      }
+
+      this.deleteLoading = false
+    },
+    showApplicationTrashModal() {
       this.$refs.context.hide()
-      this.$refs.deleteApplicationModal.show()
+      this.$refs.applicationTrashModal.show()
     },
   },
 }

web-frontend/modules/core/components/trash/TrashContents.vue

@@ -0,0 +1,157 @@
+<template>
+  <div>
+    <div class="trash__title">
+      <div class="trash__title-left">
+        <h2 class="trash__title-heading">{{ title }}</h2>
+        <div class="trash__title-description">
+          Restore deleted items from the past {{ trashDuration }}
+        </div>
+      </div>
+      <div class="trash__title-right">
+        <a
+          v-show="totalServerSideTrashContentsCount > 0 && !parentIsTrashed"
+          class="button button--error"
+          :disabled="loadingContents"
+          @click="showEmptyModalIfNotLoading"
+          >{{ emptyButtonText }}</a
+        >
+      </div>
+    </div>
+    <div v-if="loadingContents" class="loading-overlay"></div>
+    <div
+      v-else-if="totalServerSideTrashContentsCount === 0"
+      class="trash__empty"
+    >
+      <i class="trash__empty-icon fas fa-recycle"></i>
+      <div class="trash__empty-text">
+        Nothing has been deleted in the past three days.
+      </div>
+    </div>
+    <div v-else class="trash__entries">
+      <InfiniteScroll
+        :max-count="totalServerSideTrashContentsCount"
+        :current-count="trashContents.length"
+        @load-next-page="$emit('load-next-page', $event)"
+      >
+        <TrashEntry
+          v-for="item in trashContents"
+          :key="'trash-item-' + item.id"
+          :trash-entry="item"
+          :disabled="loadingContents || shouldTrashEntryBeDisabled(item)"
+          @restore="$emit('restore', $event)"
+        ></TrashEntry>
+        <div v-if="loadingNextPage" class="trash__entries-loading-wrapper">
+          <div class="loading"></div>
+        </div>
+      </InfiniteScroll>
+    </div>
+    <TrashEmptyModal
+      ref="emptyModal"
+      :name="title"
+      :loading="loadingContents"
+      :selected-is-trashed="selectedItem.trashed"
+      @empty="$emit('empty')"
+    ></TrashEmptyModal>
+  </div>
+</template>
+
+<script>
+/**
+ * Displays a infinite scrolling list of trash contents for either a selectedTrashGroup or
+ * a specific selectedTrashApplication in the selectedTrashGroup. The user can empty the trash
+ * contents permanently deleting them all, or restore individual trashed items.
+ *
+ * If the selectedItem (the selectedTrashApplication if provided, otherwise the selectedTrashGroup
+ * ) is trashed itself then the modal will display buttons and modals which indicate
+ * that they will permanently delete the selectedItem instead of just emptying it's
+ * contents.
+ */
+
+import moment from 'moment'
+import TrashEntry from '@baserow/modules/core/components/trash/TrashEntry'
+import InfiniteScroll from '@baserow/modules/core/components/infinite_scroll/InfiniteScroll'
+import TrashEmptyModal from '@baserow/modules/core/components/trash/TrashEmptyModal'
+
+export default {
+  name: 'TrashContents',
+  components: { InfiniteScroll, TrashEntry, TrashEmptyModal },
+  mixins: [],
+  props: {
+    selectedTrashGroup: {
+      type: Object,
+      required: true,
+    },
+    selectedTrashApplication: {
+      type: Object,
+      required: false,
+      default: null,
+    },
+    trashContents: {
+      type: Array,
+      required: true,
+    },
+    loadingContents: {
+      type: Boolean,
+      required: true,
+    },
+    loadingNextPage: {
+      type: Boolean,
+      required: true,
+    },
+    totalServerSideTrashContentsCount: {
+      type: Number,
+      required: true,
+    },
+  },
+  computed: {
+    parentIsTrashed() {
+      return (
+        this.selectedTrashApplication !== null &&
+        this.selectedTrashGroup.trashed
+      )
+    },
+    selectedItem() {
+      return this.selectedTrashApplication === null
+        ? this.selectedTrashGroup
+        : this.selectedTrashApplication
+    },
+    selectedItemType() {
+      return this.selectedTrashApplication === null ? 'Group' : 'Application'
+    },
+    title() {
+      const title = this.selectedItem.name
+      return title === ''
+        ? `Unnamed ${this.selectedItemType} ${this.selectedItem.id}`
+        : title
+    },
+    emptyButtonText() {
+      if (this.selectedItem.trashed) {
+        return `Delete ${this.selectedItemType} permanently`
+      } else {
+        return `Empty this ${this.selectedItemType}'s trash`
+      }
+    },
+    trashDuration() {
+      const hours = this.$env.HOURS_UNTIL_TRASH_PERMANENTLY_DELETED
+      return moment().subtract(hours, 'hours').fromNow().replace('ago', '')
+    },
+  },
+  methods: {
+    showEmptyModalIfNotLoading() {
+      if (!this.loadingContents) {
+        this.$refs.emptyModal.show()
+      }
+    },
+    shouldTrashEntryBeDisabled(entry) {
+      const selectedItemType = this.selectedItemType.toLowerCase()
+      const entryIsForSelectedItem =
+        entry.trash_item_id === this.selectedItem.id &&
+        entry.trash_item_type === selectedItemType
+      return (
+        this.parentIsTrashed ||
+        (this.selectedItem.trashed && !entryIsForSelectedItem)
+      )
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/trash/TrashEmptyModal.vue

@@ -0,0 +1,55 @@
+<template>
+  <Modal :tiny="true" :close-button="false">
+    <h3>
+      Are you sure you want to
+      {{ selectedIsTrashed ? 'permanently delete' : 'empty the trash of' }}
+      {{ name }}?
+    </h3>
+    <p>
+      This will permanently delete
+      {{
+        selectedIsTrashed ? 'it and all of its contents' : 'the listed items'
+      }}. After which they cannot be recovered.
+    </p>
+    <div class="actions">
+      <ul class="action__links">
+        <li>
+          <a @click.prevent="hide()">Cancel</a>
+        </li>
+      </ul>
+      <a class="button button button--error" @click.prevent="emitEmptyAndClose">
+        {{ selectedIsTrashed ? 'Permanently delete' : 'Empty' }}
+      </a>
+    </div>
+  </Modal>
+</template>
+
+<script>
+/**
+ * A simple confirmation modal to check that the user is sure they want to permanently
+ * delete / empty.
+ */
+import modal from '@baserow/modules/core/mixins/modal'
+
+export default {
+  name: 'TrashEmptyModal',
+  components: {},
+  mixins: [modal],
+  props: {
+    name: {
+      type: String,
+      required: true,
+    },
+    selectedIsTrashed: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  methods: {
+    emitEmptyAndClose() {
+      this.$emit('empty')
+      this.hide()
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/trash/TrashEntry.vue

@@ -0,0 +1,87 @@
+<template>
+  <div
+    ref="member"
+    class="trash-entry"
+    :class="{ 'trash-entry--disabled': disabled }"
+  >
+    <div class="trash-entry__initials">
+      {{ trashEntry.user_who_trashed | nameAbbreviation }}
+    </div>
+    <div class="trash-entry__content">
+      <div class="trash-entry__name">
+        {{ trashEntry.user_who_trashed || 'A Deleted User' }} Deleted
+        {{ trashEntry.trash_item_type }}
+        <strong>{{ trashItemTitle }}</strong>
+        {{ trashEntry.parent_name ? ' from ' + trashEntry.parent_name : '' }}
+      </div>
+      <div class="trash-entry__deleted-at-display">{{ timeAgo }}</div>
+      <span
+        v-if="trashEntry.extra_description"
+        class="trash-entry__extra-description"
+      >
+        {{ trashEntry.extra_description }}
+      </span>
+    </div>
+    <div class="trash-entry__actions">
+      <a
+        v-if="!disabled"
+        class="trash-entry__action"
+        :class="{ 'trash-entry__action--loading': trashEntry.loading }"
+        @click="emitRestoreIfNotLoading"
+      >
+        {{ trashEntry.loading ? '' : 'Restore' }}
+      </a>
+    </div>
+  </div>
+</template>
+
+<script>
+/**
+ * Displays a specific TrashEntry with a link which will trigger the restoring of the
+ * trashed entry. Shows extra information about the entry like it's name, who trashed it
+ * , how long ago it was trashed etc.
+ */
+import moment from 'moment'
+
+export default {
+  name: 'TrashEntry',
+  props: {
+    trashEntry: {
+      type: Object,
+      required: true,
+    },
+    disabled: {
+      type: Boolean,
+      required: false,
+      default: false,
+    },
+  },
+  data() {
+    return {}
+  },
+  computed: {
+    timeAgo() {
+      return moment.utc(this.trashEntry.trashed_at).fromNow()
+    },
+    trashItemTitle() {
+      if (this.trashEntry.name === '') {
+        return (
+          'Unnamed ' +
+          this.trashEntry.trash_item_type +
+          ' ' +
+          this.trashEntry.trash_item_id
+        )
+      } else {
+        return this.trashEntry.name
+      }
+    },
+  },
+  methods: {
+    emitRestoreIfNotLoading() {
+      if (!this.trashEntry.loading) {
+        this.$emit('restore', this.trashEntry)
+      }
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/trash/TrashModal.vue

@@ -0,0 +1,333 @@
+<template>
+  <Modal :sidebar="true" :full-height="true">
+    <template #sidebar>
+      <TrashSidebar
+        v-if="!loading"
+        :groups="groups"
+        :selected-trash-group="selectedTrashGroup"
+        :selected-trash-application="selectedTrashApplication"
+        @selected="selectGroupOrApp"
+      ></TrashSidebar>
+    </template>
+    <template #content>
+      <div v-if="loading" class="loading-absolute-center"></div>
+      <div v-else-if="groups.length === 0" class="placeholder">
+        <div class="placeholder__icon">
+          <i class="fas fa-layer-group"></i>
+        </div>
+        <h1 class="placeholder__title">No groups found</h1>
+        <p class="placeholder__content">
+          You aren't a member of any group. Applications like databases belong
+          to a group, so in order to create them you need to create a group.
+        </p>
+      </div>
+      <TrashContent
+        v-else
+        :selected-trash-group="selectedTrashGroup"
+        :selected-trash-application="selectedTrashApplication"
+        :trash-contents="trashContents"
+        :loading-contents="loadingContents"
+        :loading-next-page="loadingNextPage"
+        :total-server-side-trash-contents-count="
+          totalServerSideTrashContentsCount
+        "
+        @empty="onEmpty"
+        @restore="onRestore"
+        @load-next-page="loadNextPage"
+      ></TrashContent>
+    </template>
+  </Modal>
+</template>
+
+<script>
+import { mapState } from 'vuex'
+
+import modal from '@baserow/modules/core/mixins/modal'
+import { notifyIf } from '@baserow/modules/core/utils/error'
+import TrashService from '@baserow/modules/core/services/trash'
+import TrashSidebar from '@baserow/modules/core/components/trash/TrashSidebar'
+import TrashContent from '@baserow/modules/core/components/trash/TrashContents'
+
+export default {
+  name: 'TrashModal',
+  components: { TrashSidebar, TrashContent },
+  mixins: [modal],
+  props: {
+    initialGroup: {
+      type: Object,
+      required: false,
+      default: null,
+    },
+    initialApplication: {
+      type: Object,
+      required: false,
+      default: null,
+    },
+  },
+  data() {
+    return {
+      loading: true,
+      loadingContents: true,
+      loadingNextPage: false,
+      groups: [],
+      trashContents: [],
+      selectedTrashGroup: null,
+      selectedTrashApplication: null,
+      totalServerSideTrashContentsCount: 0,
+    }
+  },
+  computed: {
+    ...mapState({
+      selectedGroup: (state) => state.group.selected,
+      selectedApplication: (state) => state.application.selected,
+    }),
+  },
+  methods: {
+    /**
+     * Chooses which group to show when the modal is shown.
+     **/
+    pickInitialGroupToSelect() {
+      // The initial or selected groups will not contain the trashed flag as they so
+      // we must look them up in the groups fetched from the trash api.
+      const initialGroupWithTrashInfo = this.initialGroup
+        ? this.groups.find((i) => i.id === this.initialGroup.id)
+        : null
+      const selectedGroupWithTrashInfo = this.selectedGroup
+        ? this.groups.find((i) => i.id === this.selectedGroup.id)
+        : null
+      return (
+        initialGroupWithTrashInfo ||
+        selectedGroupWithTrashInfo ||
+        this.groups[0] || // When all groups are trashed we want to pick the first one.
+        null
+      )
+    },
+    /**
+     * Chooses which app to show when the modal is shown.
+     **/
+    pickInitialApplicationToSelect(firstGroupToShow) {
+      if (firstGroupToShow === null) {
+        return null
+      } else {
+        // The initial or selected apps will not contain the trashed flag as they so
+        // we must look them up in the groups fetched from the trash api.
+        const applications = firstGroupToShow.applications
+        if (this.initialApplication || this.initialGroup) {
+          // When either of the initial props are set we have been opened via a context
+          // menu shortcut.
+          return this.initialApplication
+            ? applications.find((i) => i.id === this.initialApplication.id)
+            : null
+        } else {
+          return this.selectedApplication
+            ? applications.find((i) => i.id === this.selectedApplication.id)
+            : null
+        }
+      }
+    },
+    /**
+     * Loads the structure of the trash modal from the server, selects an initial
+     * group or application depending on the props and shows the trash modal.
+     **/
+    async show(...args) {
+      modal.methods.show.call(this, ...args)
+
+      this.loading = true
+      this.groups = []
+      this.selectedTrashGroup = null
+      this.selectedTrashApplication = null
+
+      try {
+        const { data } = await TrashService(this.$client).fetchStructure()
+        this.groups = data.groups
+        const initialGroup = this.pickInitialGroupToSelect()
+        await this.selectGroupOrApp({
+          group: initialGroup,
+          application: this.pickInitialApplicationToSelect(initialGroup),
+        })
+      } catch (error) {
+        notifyIf(error, 'trash')
+        this.hide()
+      }
+      this.loading = false
+    },
+    /**
+     * Loads the next page of trash contents for the currently selected application.
+     */
+    async loadTrashContentsPage(nextPage) {
+      if (
+        this.selectedTrashGroup === null &&
+        this.selectedTrashApplication === null
+      ) {
+        return
+      }
+      try {
+        const { data } = await TrashService(this.$client).fetchContents({
+          page: nextPage,
+          groupId: this.selectedTrashGroup.id,
+          applicationId:
+            this.selectedTrashApplication !== null
+              ? this.selectedTrashApplication.id
+              : null,
+        })
+        this.totalServerSideTrashContentsCount = data.count
+        data.results.forEach((entry) => {
+          entry.loading = false
+          this.trashContents.push(entry)
+        })
+      } catch (error) {
+        notifyIf(error, 'trash')
+      }
+    },
+    /**
+     * Switches to a different group or application to display the trash contents for
+     * and triggers the fetch for the first page of contents.
+     */
+    async selectGroupOrApp({ group, application = null }) {
+      this.selectedTrashGroup = group
+      this.selectedTrashApplication = application
+      this.loadingContents = true
+      this.trashContents = []
+      this.totalServerSideTrashContentsCount = 0
+      await this.loadTrashContentsPage(1)
+      this.loadingContents = false
+    },
+    /**
+     * Loads another page of contents in after we have already loaded the initial
+     * page of contents, hence we want to use a different loading indicator as it is
+     * ok to say, restore an item whilst we are loading in another page.
+     */
+    async loadNextPage(nextPage) {
+      this.loadingNextPage = true
+      await this.loadTrashContentsPage(nextPage)
+      this.loadingNextPage = false
+    },
+    /**
+     * Triggered when a user requests a trashEntry be restored. Sends the request to
+     * the server, updates the client side state if successful and updates the trash
+     * structure if say a group or application was restored.
+     */
+    async onRestore(trashEntry) {
+      try {
+        trashEntry.loading = true
+        await TrashService(this.$client).restore({
+          trash_item_type: trashEntry.trash_item_type,
+          trash_item_id: trashEntry.trash_item_id,
+          parent_trash_item_id: trashEntry.parent_trash_item_id,
+        })
+        const index = this.trashContents.findIndex(
+          (t) => t.id === trashEntry.id
+        )
+        this.trashContents.splice(index, 1)
+        this.totalServerSideTrashContentsCount--
+        this.updateStructureIfGroupOrAppRestored(trashEntry)
+      } catch (error) {
+        notifyIf(error, 'trash')
+      }
+      trashEntry.loading = false
+    },
+    updateStructureIfGroupOrAppRestored(trashEntry) {
+      /**
+       * If a group or app is trashed it is displayed with a strike through it's text.
+       * This method checks if a restored trash entry is a group or application and
+       * if so updates the state of said group/app so it no longer is displayed as
+       * trashed.
+       */
+      const trashItemId = trashEntry.trash_item_id
+      const trashItemType = trashEntry.trash_item_type
+      if (trashItemType === 'group') {
+        const index = this.groups.findIndex((group) => group.id === trashItemId)
+        this.groups[index].trashed = false
+      } else if (trashItemType === 'application') {
+        const index = this.selectedTrashGroup.applications.findIndex(
+          (app) => app.id === trashItemId
+        )
+        this.selectedTrashGroup.applications[index].trashed = false
+      }
+    },
+    /**
+     * Triggered when the user has requested the currently selected group or app
+     * should be emptied. If the selected item is trashed itself the empty operation
+     * will permanently delete the selected item also. Once emptied this method will
+     * ensure that any now permanently deleted groups or apps are removed from the
+     * sidebar.
+     */
+    async onEmpty() {
+      this.loadingContents = true
+      try {
+        const applicationIdOrNull =
+          this.selectedTrashApplication !== null
+            ? this.selectedTrashApplication.id
+            : null
+        await TrashService(this.$client).emptyContents({
+          groupId: this.selectedTrashGroup.id,
+          applicationId: applicationIdOrNull,
+        })
+        this.removeGroupOrAppFromSidebarIfNowPermDeleted()
+        this.trashContents = []
+        this.totalServerSideTrashContentsCount = 0
+      } catch (error) {
+        notifyIf(error, 'trash')
+      }
+      this.loadingContents = false
+    },
+    removeSelectedAppFromSidebar() {
+      const applicationId = this.selectedTrashApplication.id
+
+      const indexToDelete = this.selectedTrashGroup.applications.findIndex(
+        (app) => app.id === applicationId
+      )
+      this.selectedTrashGroup.applications.splice(indexToDelete, 1)
+      if (this.selectedTrashGroup.applications.length > 0) {
+        this.selectedTrashApplication = this.selectedTrashGroup.applications[0]
+      } else {
+        this.selectedTrashApplication = null
+      }
+    },
+    removeSelectedTrashGroupFromSidebar() {
+      const indexToDelete = this.groups.findIndex(
+        (group) => group.id === this.selectedTrashGroup.id
+      )
+      this.groups.splice(indexToDelete, 1)
+      if (this.groups.length > 0) {
+        this.selectedTrashGroup = this.groups[0]
+      } else {
+        this.selectedTrashGroup = null
+      }
+    },
+    /**
+     * Updates the trash structure to remove any deleted groups or applications after
+     * an empty is performed.
+     */
+    removeGroupOrAppFromSidebarIfNowPermDeleted() {
+      if (
+        this.selectedTrashApplication !== null &&
+        this.selectedTrashApplication.trashed
+      ) {
+        this.removeSelectedAppFromSidebar()
+        this.selectGroupOrApp({
+          group: this.selectedTrashGroup,
+          application: this.selectedTrashApplication,
+        })
+      } else if (this.selectedTrashGroup.trashed) {
+        this.removeSelectedTrashGroupFromSidebar()
+        this.selectGroupOrApp({
+          group: this.selectedTrashGroup,
+          application: this.selectedTrashApplication,
+        })
+      } else if (this.selectedTrashApplication === null) {
+        // The group was emptied, it might have contained trashed applications hence
+        // we need to search through the trash and remove any now deleted applications.
+        for (const app of this.selectedTrashGroup.applications.slice()) {
+          if (app.trashed) {
+            const index = this.selectedTrashGroup.applications.findIndex(
+              (i) => i.id === app.id
+            )
+            this.selectedTrashGroup.applications.splice(index, 1)
+          }
+        }
+      }
+    },
+  },
+}
+</script>

web-frontend/modules/core/components/trash/TrashSidebar.vue

@@ -0,0 +1,105 @@
+<template>
+  <div>
+    <div class="modal-sidebar__head">
+      <div class="modal-sidebar__head-icon-and-name">
+        <i class="modal-sidebar__head-icon-and-name-icon fas fa-trash"></i>
+        Trash
+      </div>
+    </div>
+    <ul class="trash-sidebar__groups">
+      <li
+        v-for="group in groups"
+        :key="'trash-group-' + group.id"
+        class="trash-sidebar__group"
+        :class="{
+          'trash-sidebar__group--active': isSelectedTrashGroup(group),
+          'trash-sidebar__group--open': isSelectedTrashGroupApplication(group),
+          'trash-sidebar__group--trashed': group.trashed,
+        }"
+      >
+        <a
+          class="trash-sidebar__group-link"
+          @click="emitIfNotAlreadySelectedTrashGroup(group)"
+        >
+          {{ group.name || 'Unnamed group ' + group.id }}
+        </a>
+        <ul class="trash-sidebar__applications">
+          <li
+            v-for="application in group.applications"
+            :key="'trash-application-' + application.id"
+            class="trash-sidebar__application"
+            :class="{
+              'trash-sidebar__application--active': isSelectedApp(application),
+              'trash-sidebar__application--trashed':
+                group.trashed || application.trashed,
+            }"
+          >
+            <a
+              class="trash-sidebar__application-link"
+              @click="
+                emitIfNotAlreadySelectedTrashApplication(group, application)
+              "
+              >{{
+                application.name || 'Unnamed application ' + application.id
+              }}</a
+            >
+          </li>
+        </ul>
+      </li>
+    </ul>
+  </div>
+</template>
+
+<script>
+export default {
+  name: 'TrashSidebar',
+  props: {
+    groups: {
+      type: Array,
+      required: true,
+    },
+    selectedTrashGroup: {
+      type: Object,
+      required: false,
+      default: null,
+    },
+    selectedTrashApplication: {
+      type: Object,
+      required: false,
+      default: null,
+    },
+  },
+  methods: {
+    isSelectedTrashGroup(group) {
+      return (
+        group.id === this.selectedTrashGroup.id &&
+        this.selectedTrashApplication === null
+      )
+    },
+    isSelectedTrashGroupApplication(group) {
+      return group.applications.some((application) =>
+        this.isSelectedApp(application)
+      )
+    },
+    isSelectedApp(app) {
+      return (
+        this.selectedTrashApplication !== null &&
+        app.id === this.selectedTrashApplication.id
+      )
+    },
+    emitIfNotAlreadySelectedTrashGroup(group) {
+      if (!this.isSelectedTrashGroup(group)) {
+        this.emitSelected({ group })
+      }
+    },
+    emitIfNotAlreadySelectedTrashApplication(group, application) {
+      if (!this.isSelectedApp(application)) {
+        this.emitSelected({ group, application })
+      }
+    },
+    emitSelected(selected) {
+      this.$emit('selected', selected)
+    },
+  },
+}
+</script>

web-frontend/modules/core/module.js

@@ -51,6 +51,12 @@ export default function DatabaseModule(options) {
           key: 'INITIAL_TABLE_DATA_LIMIT',
           default: null,
         },
+        {
+          // If you change this default please also update the default for the
+          // backend found in src/baserow/config/settings/base.py:321
+          key: 'HOURS_UNTIL_TRASH_PERMANENTLY_DELETED',
+          default: 24 * 3,
+        },
       ],
     },
   ])

web-frontend/modules/core/pages/styleGuide.vue

@@ -907,7 +907,7 @@
             </a>
             <div class="modal__box-sidebar">
               <div class="modal-sidebar__head">
-                <div class="modal-sidebar__head-icon">B</div>
+                <div class="modal-sidebar__head-initials-icon">B</div>
                 <div class="modal-sidebar__head-name">Settings</div>
               </div>
               <ul class="modal-sidebar__nav">

web-frontend/modules/core/plugins/clientHandler.js

@@ -68,6 +68,11 @@ class ErrorHandler {
         "Couldn't create field.",
         "The action couldn't be completed because the field count exceeds the limit"
       ),
+      ERROR_CANNOT_RESTORE_PARENT_BEFORE_CHILD: new ResponseErrorMessage(
+        'Please restore the parent first.',
+        'You cannot restore this because as within something which is already' +
+          ' trashed. Please restore the parent item first.'
+      ),
     }
 
     // A temporary notFoundMap containing the error messages for when the