Resolve "Add files lower than view filter"

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

@@ -565,6 +565,7 @@ SPECTACULAR_SETTINGS = {
             "not_equal",
             "filename_contains",
             "has_file_type",
+            "files_lower_than",
             "contains",
             "contains_not",
             "length_is_lower_than",

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

@@ -306,6 +306,7 @@ class DatabaseConfig(AppConfig):
             EmptyViewFilterType,
             EqualViewFilterType,
             FilenameContainsViewFilterType,
+            FilesLowerThanViewFilterType,
             HasFileTypeViewFilterType,
             HigherThanViewFilterType,
             IsEvenAndWholeViewFilterType,
@@ -328,6 +329,7 @@ class DatabaseConfig(AppConfig):
         view_filter_type_registry.register(EqualViewFilterType())
         view_filter_type_registry.register(NotEqualViewFilterType())
         view_filter_type_registry.register(FilenameContainsViewFilterType())
+        view_filter_type_registry.register(FilesLowerThanViewFilterType()),
         view_filter_type_registry.register(HasFileTypeViewFilterType())
         view_filter_type_registry.register(ContainsViewFilterType())
         view_filter_type_registry.register(ContainsNotViewFilterType())

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

@@ -5,7 +5,7 @@ from math import ceil, floor
 from typing import Any, Dict, Optional, Tuple, Union
 
 from django.db.models import DateField, DateTimeField, IntegerField, Q
-from django.db.models.expressions import F
+from django.db.models.expressions import F, Func
 from django.db.models.functions import Extract, Length, Mod, TruncDate
 
 import pytz
@@ -146,6 +146,39 @@ class HasFileTypeViewFilterType(ViewFilterType):
             return Q()
 
 
+class FilesLowerThanViewFilterType(ViewFilterType):
+    """
+    The files lower than filter checks if the number of file objects present
+    in a column of type file is smaller than a given value.
+
+    It is only compatible with fields.JSONField which contain a list of File
+    JSON Objects.
+    """
+
+    type = "files_lower_than"
+    compatible_field_types = [FileFieldType.type]
+
+    def get_filter(self, field_name, value, model_field, field):
+        value = value.strip()
+
+        # If a non numeric value has been provided we do not want to filter.
+        if not value.lstrip("-").isdigit():
+            return Q()
+
+        # Annotate the query with the length of the JSON array, using the
+        # proper PostgreSQL function
+        # See: https://www.postgresql.org/docs/current/functions-json.html
+        annotation_query = Func(
+            F(field_name),
+            function="jsonb_array_length",
+            output_field=IntegerField(),
+        )
+        return AnnotatedQ(
+            annotation={f"{field_name}_length": annotation_query},
+            q={f"{field_name}_length__lt": int(value)},
+        )
+
+
 class ContainsViewFilterType(ViewFilterType):
     """
     The contains filter checks if the field value contains the provided filter value.

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

@@ -3617,6 +3617,76 @@ def test_has_file_type(data_fixture):
     assert row_with_single_document_and_multiple_images.id in ids
 
 
+@pytest.mark.django_db
+def test_files_lower_than(data_fixture):
+    user = data_fixture.create_user()
+    table = data_fixture.create_database_table(user=user)
+    grid_view = data_fixture.create_grid_view(table=table)
+    file_field = data_fixture.create_file_field(table=table)
+
+    handler = ViewHandler()
+    model = table.get_model()
+
+    row_without_files = model.objects.create(**{f"field_{file_field.id}": []})
+    row_with_one_file = model.objects.create(
+        **{
+            f"field_{file_field.id}": [
+                {"visible_name": "test_file_1.txt", "is_image": False},
+            ],
+        }
+    )
+    row_with_two_files = model.objects.create(
+        **{
+            f"field_{file_field.id}": [
+                {"visible_name": "test_file_1.txt", "is_image": False},
+                {"visible_name": "test_file_2.txt", "is_image": False},
+            ],
+        },
+    )
+    row_with_three_files = model.objects.create(
+        **{
+            f"field_{file_field.id}": [
+                {"visible_name": "test_file_1.txt", "is_image": False},
+                {"visible_name": "test_file_2.txt", "is_image": False},
+                {"visible_name": "test_file_3.txt", "is_image": False},
+            ],
+        },
+    )
+
+    # There are no rows whose file column has less than 0 files
+    view_filter = data_fixture.create_view_filter(
+        view=grid_view,
+        field=file_field,
+        type="files_lower_than",
+        value="0",
+    )
+    ids = [r.id for r in handler.apply_filters(grid_view, model.objects.all()).all()]
+    assert len(ids) == 0
+
+    # There are two rows whose file column has less than 2 files
+    view_filter.value = 2
+    view_filter.save()
+    ids = [r.id for r in handler.apply_filters(grid_view, model.objects.all()).all()]
+    assert len(ids) == 2
+    assert row_without_files.id in ids
+    assert row_with_one_file.id in ids
+
+    # There are three rows whose file column has less than 4 files
+    view_filter.value = 4
+    view_filter.save()
+    ids = [r.id for r in handler.apply_filters(grid_view, model.objects.all()).all()]
+    assert len(ids) == 4
+    assert row_without_files.id in ids
+    assert row_with_one_file.id in ids
+    assert row_with_two_files.id in ids
+    assert row_with_three_files.id in ids
+
+    view_filter.value = "-1"
+    view_filter.save()
+    ids = [r.id for r in handler.apply_filters(grid_view, model.objects.all()).all()]
+    assert len(ids) == 0
+
+
 @pytest.mark.django_db
 def test_link_row_preload_values(data_fixture, django_assert_num_queries):
     user = data_fixture.create_user()

changelog/entries/unreleased/feature/1771_add_a_new_view_filter_for_selecting_rows_whose_file_columns_.json

@@ -0,0 +1,7 @@
+{
+    "type": "feature",
+    "message": "Add a new view filter for selecting rows whose file columns have less files than a given number",
+    "issue_number": 1771,
+    "bullet_points": [],
+    "created_at": "2023-09-16"
+}

web-frontend/locales/en.json

@@ -175,7 +175,8 @@
         "lowerThan": "lower than",
         "isEvenAndWhole": "is even and whole",
         "lengthIsLowerThan": "length is lower than",
-        "hasFileType": "has file type"
+        "hasFileType": "has file type",
+        "filesLowerThan": "files lower than"
     },
     "viewType": {
         "grid": "Grid",

web-frontend/modules/database/plugin.js

@@ -34,6 +34,7 @@ import {
   DateNotEqualViewFilterType,
   ContainsViewFilterType,
   FilenameContainsViewFilterType,
+  FilesLowerThanViewFilterType,
   HasFileTypeViewFilterType,
   ContainsNotViewFilterType,
   LengthIsLowerThanViewFilterType,
@@ -361,6 +362,10 @@ export default (context) => {
     new FilenameContainsViewFilterType(context)
   )
   app.$registry.register('viewFilter', new HasFileTypeViewFilterType(context))
+  app.$registry.register(
+    'viewFilter',
+    new FilesLowerThanViewFilterType(context)
+  )
   app.$registry.register(
     'viewFilter',
     new LengthIsLowerThanViewFilterType(context)

web-frontend/modules/database/viewFilters.js

@@ -281,6 +281,33 @@ export class HasFileTypeViewFilterType extends ViewFilterType {
   }
 }
 
+export class FilesLowerThanViewFilterType extends ViewFilterType {
+  static getType() {
+    return 'files_lower_than'
+  }
+
+  getName() {
+    const { i18n } = this.app
+    return i18n.t('viewFilter.filesLowerThan')
+  }
+
+  getExample() {
+    return '2'
+  }
+
+  getInputComponent() {
+    return ViewFilterTypeNumber
+  }
+
+  getCompatibleFieldTypes() {
+    return ['file']
+  }
+
+  matches(rowValue, filterValue, field, fieldType) {
+    return rowValue.length < parseInt(filterValue)
+  }
+}
+
 export class ContainsViewFilterType extends ViewFilterType {
   static getType() {
     return 'contains'

web-frontend/test/unit/database/viewFiltersMatch.spec.js

@@ -20,6 +20,7 @@ import {
   MultipleSelectHasFilterType,
   MultipleSelectHasNotFilterType,
   HasFileTypeViewFilterType,
+  FilesLowerThanViewFilterType,
   LengthIsLowerThanViewFilterType,
   LinkRowContainsFilterType,
   LinkRowNotContainsFilterType,
@@ -1309,4 +1310,26 @@ describe('All Tests', () => {
       )
     ).toBe(true)
   })
+
+  test('FilesLowerThanFilterType', () => {
+    expect(new FilesLowerThanViewFilterType().matches([], 0)).toBe(false)
+    expect(
+      new FilesLowerThanViewFilterType().matches(
+        [
+          { visible_name: 'test_file_1.txt' },
+          { visible_name: 'test_file_2.txt' },
+        ],
+        2
+      )
+    ).toBe(false)
+    expect(
+      new FilesLowerThanViewFilterType().matches(
+        [
+          { visible_name: 'test_file_1.txt' },
+          { visible_name: 'test_file_2.txt' },
+        ],
+        3
+      )
+    ).toBe(true)
+  })
 })