♻️(backend) skip saving in database a document when payload is empty

The frontend application is making PATCH request with an empty body.
This PATCH request is not making any change but an UPDATE sql query is
made, the `updated_at` field is the only one updated. When can skip this
save in the databse by returning the Document instance in the serializer
update method

CHANGELOG.md

@@ -16,15 +16,14 @@ and this project adheres to
 - ♿️(frontend) add sr-only format to export download button #2088
 - ♿️(frontend) announce formatting shortcuts for screen readers #2070
 - ✨(frontend) add markdown copy icon for Copy as Markdown option #2096
+- ♻️(backend) skip saving in database a document when payload is empty #2062
 
 ### Fixed
 
 - ♿️(frontend) fix aria-labels for table of contents #2065
-
-### Fixed
-
 - 🐛(backend) allow using search endpoint without refresh token enabled #2097
 
+
 ## [v4.8.2] - 2026-03-19
 
 ### Added

src/backend/core/api/serializers.py

@@ -300,6 +300,15 @@ class DocumentSerializer(ListDocumentSerializer):
 
         return file
 
+    def update(self, instance, validated_data):
+        """
+        When no data is sent on the update, skip making the update in the database and return
+        directly the instance unchanged.
+        """
+        if not validated_data:
+            return instance  # No data provided, skip the update
+        return super().update(instance, validated_data)
+
     def save(self, **kwargs):
         """
         Process the content field to extract attachment keys and update the document's

src/backend/core/tests/documents/test_api_documents_update.py

@@ -4,6 +4,7 @@ Tests for Documents API endpoint in impress's core app: update
 # pylint: disable=too-many-lines
 
 import random
+from unittest.mock import patch
 
 from django.contrib.auth.models import AnonymousUser
 from django.core.cache import cache
@@ -1429,3 +1430,47 @@ def test_api_documents_patch_invalid_content():
     )
     assert response.status_code == 400
     assert response.json() == {"content": ["Invalid base64 content."]}
+
+
+@responses.activate
+def test_api_documents_patch_empty_body(settings):
+    """
+    Test when data is empty the document should not be updated.
+    The `updated_at` property should not change asserting that no update in the database is made.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+    session_key = client.session.session_key
+
+    document = factories.DocumentFactory(users=[(user, "owner")], creator=user)
+    document_updated_at = document.updated_at
+
+    settings.COLLABORATION_API_URL = "http://example.com/"
+    settings.COLLABORATION_SERVER_SECRET = "secret-token"
+    settings.COLLABORATION_WS_NOT_CONNECTED_READY_ONLY = True
+    endpoint_url = (
+        f"{settings.COLLABORATION_API_URL}get-connections/"
+        f"?room={document.id}&sessionKey={session_key}"
+    )
+    ws_resp = responses.get(endpoint_url, json={"count": 3, "exists": True})
+
+    assert cache.get(f"docs:no-websocket:{document.id}") is None
+
+    old_document_values = serializers.DocumentSerializer(instance=document).data
+
+    with patch("core.models.Document.save") as mock_document_save:
+        response = client.patch(
+            f"/api/v1.0/documents/{document.id!s}/",
+            content_type="application/json",
+        )
+    mock_document_save.assert_not_called()
+    assert response.status_code == 200
+
+    document = models.Document.objects.get(id=document.id)
+    new_document_values = serializers.DocumentSerializer(instance=document).data
+    assert new_document_values == old_document_values
+    assert document_updated_at == document.updated_at
+    assert cache.get(f"docs:no-websocket:{document.id}") is None
+    assert ws_resp.call_count == 1