fix: fix chat assistant response mode blocking is not work (#32394)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

api/tests/unit_tests/services/test_app_generate_service.py

@@ -63,3 +63,56 @@ def test_workflow_blocking_injects_pause_state_config(mocker, monkeypatch):
     pause_state_config = call_kwargs.get("pause_state_config")
     assert pause_state_config is not None
     assert pause_state_config.state_owner_user_id == "owner-id"
+
+
+def test_advanced_chat_blocking_returns_dict_and_does_not_use_event_retrieval(mocker, monkeypatch):
+    """
+    Regression test: ADVANCED_CHAT in blocking mode should return a plain dict
+    (non-streaming), and must not go through the async retrieve_events path.
+    Keeps behavior consistent with WORKFLOW blocking branch.
+    """
+    # Disable billing and stub RateLimit to a no-op that just passes values through
+    monkeypatch.setattr(app_generate_service_module.dify_config, "BILLING_ENABLED", False)
+    mocker.patch("services.app_generate_service.RateLimit", _DummyRateLimit)
+
+    # Arrange a fake workflow and wire AppGenerateService._get_workflow to return it
+    workflow = MagicMock()
+    workflow.id = "workflow-id"
+    mocker.patch.object(AppGenerateService, "_get_workflow", return_value=workflow)
+
+    # Spy on the streaming retrieval path to ensure it's NOT called
+    retrieve_spy = mocker.patch("services.app_generate_service.AdvancedChatAppGenerator.retrieve_events")
+
+    # Make AdvancedChatAppGenerator.generate return a plain dict when streaming=False
+    generate_spy = mocker.patch(
+        "services.app_generate_service.AdvancedChatAppGenerator.generate",
+        return_value={"result": "ok"},
+    )
+
+    # Minimal app model for ADVANCED_CHAT
+    app_model = MagicMock()
+    app_model.mode = AppMode.ADVANCED_CHAT
+    app_model.id = "app-id"
+    app_model.tenant_id = "tenant-id"
+    app_model.max_active_requests = 0
+    app_model.is_agent = False
+
+    user = MagicMock()
+    user.id = "user-id"
+
+    # Must include query and inputs for AdvancedChatAppGenerator
+    args = {"workflow_id": "wf-1", "query": "hello", "inputs": {}}
+
+    # Act: call service with streaming=False (blocking mode)
+    result = AppGenerateService.generate(
+        app_model=app_model,
+        user=user,
+        args=args,
+        invoke_from=MagicMock(),
+        streaming=False,
+    )
+
+    # Assert: returns the dict from generate(), and did not call retrieve_events()
+    assert result == {"result": "ok"}
+    assert generate_spy.call_args.kwargs.get("streaming") is False
+    retrieve_spy.assert_not_called()