fix(functions): Support EXT_INSTANCE_ID in current scope and improve fallback warning suggestion

Updated _resolve_resource to support resolving current scope using EXT_INSTANCE_ID (checking it first before falling back to FIREBASE_KIT_INSTANCE_ID) for completeness and consistency. Updated _log_fallback_warning message to suggest the more idiomatic functions.FunctionScope.

Author: inlined

firebase_admin/functions.py

@@ -248,8 +248,12 @@ def _resolve_resource(self, scope: FunctionScope) -> Tuple[Resource, Optional[st
         extension_or_kit_id = None
 
         if scope.type == 'current':
+            ext_instance_id = os.environ.get('EXT_INSTANCE_ID')
             kit_instance_id = os.environ.get('FIREBASE_KIT_INSTANCE_ID')
-            if kit_instance_id:
+            if ext_instance_id:
+                resource_id = f'ext-{ext_instance_id}-{resource_id}'
+                extension_or_kit_id = ext_instance_id
+            elif kit_instance_id:
                 resource_id = f'kit-{kit_instance_id}-{resource_id}'
                 extension_or_kit_id = kit_instance_id
         elif scope.type == 'global':
@@ -278,7 +282,7 @@ def _log_fallback_warning(self, function_name: str, instance: str) -> None:
             f"Targeting kit {instance} with the legacy extensions API, "
             "which has performance implications. Please change the call "
             f"task_queue('{function_name}', '{instance}') to "
-            f"task_queue('{function_name}', FunctionScope('kit', '{instance}'))",
+            f"task_queue('{function_name}', functions.FunctionScope('kit', '{instance}'))",
             UserWarning,
             stacklevel=3
         )

tests/test_functions.py

@@ -290,15 +290,21 @@ def test_enqueue_current_scope_default(self):
         assert recorder[0].url == expected_url
 
     def test_enqueue_current_scope_env_vars_ext(self, monkeypatch):
-        # Python SDK does not handle EXT_INSTANCE_ID since no extensions use Python
         monkeypatch.setenv('EXT_INSTANCE_ID', 'my-ext')
-        _, recorder = self._instrument_functions_service()
+        expected_queue = 'ext-my-ext-test-function-name'
+        response_payload = json.dumps({
+            'name': (
+                f'projects/test-project/locations/us-central1/'
+                f'queues/{expected_queue}/tasks/test-task-id'
+            )
+        })
+        _, recorder = self._instrument_functions_service(payload=response_payload)
         queue = functions.task_queue('test-function-name')
         queue.enqueue(_DEFAULT_DATA)
         assert len(recorder) == 1
         expected_url = (
             _CLOUD_TASKS_URL + 'projects/test-project/locations/us-central1/'
-            'queues/test-function-name/tasks'
+            f'queues/{expected_queue}/tasks'
         )
         assert recorder[0].url == expected_url
 
@@ -321,6 +327,26 @@ def test_enqueue_current_scope_env_vars_kit(self, monkeypatch):
         )
         assert recorder[0].url == expected_url
 
+    def test_enqueue_current_scope_env_vars_precedence(self, monkeypatch):
+        monkeypatch.setenv('EXT_INSTANCE_ID', 'my-ext')
+        monkeypatch.setenv('FIREBASE_KIT_INSTANCE_ID', 'my-kit')
+        expected_queue = 'ext-my-ext-test-function-name'
+        response_payload = json.dumps({
+            'name': (
+                f'projects/test-project/locations/us-central1/'
+                f'queues/{expected_queue}/tasks/test-task-id'
+            )
+        })
+        _, recorder = self._instrument_functions_service(payload=response_payload)
+        queue = functions.task_queue('test-function-name')
+        queue.enqueue(_DEFAULT_DATA)
+        assert len(recorder) == 1
+        expected_url = (
+            _CLOUD_TASKS_URL + 'projects/test-project/locations/us-central1/'
+            f'queues/{expected_queue}/tasks'
+        )
+        assert recorder[0].url == expected_url
+
     def test_enqueue_global_scope(self):
         _, recorder = self._instrument_functions_service()
         queue = functions.task_queue(
@@ -392,8 +418,8 @@ def test_enqueue_fallback_flow(self):
             task_id = queue.enqueue(_DEFAULT_DATA)
         assert task_id == 'task-123'
         assert queue._scope.type == 'extension_or_kit'
-        assert len(record) == 1
         assert "Targeting kit my-instance with the legacy extensions API" in str(record[0].message)
+        assert "functions.FunctionScope('kit', 'my-instance')" in str(record[0].message)
         assert len(recorder) == 2
         assert 'ext-my-instance-test-function-name' in recorder[0].url
         assert 'kit-my-instance-test-function-name' in recorder[1].url
@@ -415,6 +441,7 @@ def test_delete_fallback_flow(self):
         assert queue._scope.type == 'extension_or_kit'
         assert len(record) == 1
         assert "Targeting kit my-instance with the legacy extensions API" in str(record[0].message)
+        assert "functions.FunctionScope('kit', 'my-instance')" in str(record[0].message)
         assert len(recorder) == 2
         assert 'ext-my-instance-test-function-name/tasks/task-123' in recorder[0].url
         assert 'kit-my-instance-test-function-name/tasks/task-123' in recorder[1].url