✨(backend) allow filtering by documents marked as favorite

We recently allowed authenticated users to mark a document as favorite.
We were lacking the possibility for users to see only the documents
they marked as favorite.

src/backend/core/api/filters.py

@@ -15,10 +15,13 @@ class DocumentFilter(django_filters.FilterSet):
     is_creator_me = django_filters.BooleanFilter(
         method="filter_is_creator_me", label=_("Creator is me")
     )
+    is_favorite = django_filters.BooleanFilter(
+        method="filter_is_favorite", label=_("Favorite")
+    )
 
     class Meta:
         model = models.Document
-        fields = ["is_creator_me"]
+        fields = ["is_creator_me", "is_favorite"]
 
     # pylint: disable=unused-argument
     def filter_is_creator_me(self, queryset, name, value):
@@ -47,9 +50,9 @@ class DocumentFilter(django_filters.FilterSet):
         Filter documents based on whether they are marked as favorite by the current user.
 
         Example:
-            - /api/v1.0/documents/?favorite=true
+            - /api/v1.0/documents/?is_favorite=true
                 → Filters documents marked as favorite by the logged-in user
-            - /api/v1.0/documents/?favorite=false
+            - /api/v1.0/documents/?is_favorite=false
                 → Filters documents not marked as favorite by the logged-in user
         """
         user = self.request.user
@@ -57,7 +60,7 @@ class DocumentFilter(django_filters.FilterSet):
         if not user.is_authenticated:
             return queryset
 
-        clause = "filter" if value else "exclude"
-        return getattr(queryset, clause)(
-            favorited_by_users__user=user, favorited_by_users__is_favorite=True
-        )
+        if value:
+            return queryset.filter(favorited_by_users__user=user)
+
+        return queryset.exclude(favorited_by_users__user=user)

src/backend/core/api/viewsets.py

@@ -324,10 +324,12 @@ class DocumentViewSet(
     Filtering:
         - `is_creator_me=true`: Returns documents created by the current user.
         - `is_creator_me=false`: Returns documents created by other users.
+        - `is_favorite=true`: Returns documents marked as favorite by the current user
+        - `is_favorite=false`: Returns documents not marked as favorite by the current user
 
     Example Usage:
-        - GET /api/v1.0/documents/?creator=me
-        - GET /api/v1.0/documents/?creator=other
+        - GET /api/v1.0/documents/?is_creator_me=true&is_favorite=true
+        - GET /api/v1.0/documents/?is_creator_me=false
     """
 
     filter_backends = [filters.DjangoFilterBackend, drf_filters.OrderingFilter]