Support annotation metadata in annotation PATCH-ing

h/schemas/annotation.py

@@ -230,6 +230,8 @@ def validate(self, data):
                 new_appstruct.get("target_uri", self.existing_target_uri),
             )
 
+        new_appstruct["metadata"] = appstruct.pop("metadata", None)
+
         new_appstruct["extra"] = appstruct
 
         return new_appstruct

h/services/annotation_write.py

@@ -110,6 +110,7 @@ def update_annotation(
         """
         initial_target_uri = annotation.target_uri
 
+        annotation_metadata = data.pop("metadata", None)
         self._update_annotation_values(annotation, data)
         if update_timestamp:
             annotation.updated = datetime.utcnow()
@@ -132,9 +133,11 @@ def update_annotation(
                 document.get("document_uri_dicts", {}),
                 updated=annotation.updated,
             )
-
         self.upsert_annotation_slim(annotation)
 
+        if annotation_metadata:
+            self._annotation_metadata_service.set(annotation, annotation_metadata)
+
         # The search index service by default does not reindex if the existing ES
         # entry's timestamp matches the DB timestamp. If we're not changing this
         # timestamp, we need to force reindexing.

tests/h/services/annotation_write_test.py

@@ -150,6 +150,20 @@ def test_update_annotation_with_non_defaults(self, svc, annotation, search_index
         )
         assert result.updated == then
 
+    def test_update_annotation_with_metadata(
+        self, svc, annotation, annotation_metadata_service
+    ):
+        result = svc.update_annotation(
+            annotation,
+            {"metadata": sentinel.metadata},
+            update_timestamp=False,
+            reindex_tag="custom_tag",
+        )
+
+        annotation_metadata_service.set.assert_called_once_with(
+            result, sentinel.metadata
+        )
+
     def test__validate_group_with_no_group(self, svc, annotation):
         annotation.group = None