feat: route workflow image inputs natively

backend/tests/test_workflow_router.py

@@ -72,6 +72,77 @@ class WorkflowLLMRouterTest(unittest.IsolatedAsyncioTestCase):
         )
         self.assertNotIn("developer", str(requests[0]["messages"]))
 
+    async def test_routes_with_the_current_multimodal_user_message(self):
+        requests = []
+
+        class FakeCompletions:
+            async def create(self, **kwargs):
+                requests.append(kwargs)
+                return SimpleNamespace(
+                    choices=[
+                        SimpleNamespace(
+                            message=SimpleNamespace(
+                                tool_calls=[
+                                    SimpleNamespace(
+                                        function=SimpleNamespace(
+                                            name="goto_confirm",
+                                            arguments="{}",
+                                        )
+                                    )
+                                ]
+                            )
+                        )
+                    ]
+                )
+
+        class FakeClient:
+            def __init__(self, **_kwargs):
+                self.chat = SimpleNamespace(completions=FakeCompletions())
+
+            async def close(self):
+                return None
+
+        router = WorkflowLLMRouter(
+            AssistantConfig(
+                type="workflow",
+                model="visual-model",
+                llm_api_key="secret",
+                llm_base_url="https://llm.test/v1",
+            )
+        )
+        image_message = {
+            "role": "user",
+            "content": [
+                {"type": "text", "text": "请检查车牌照片"},
+                {
+                    "type": "image_url",
+                    "image_url": {"url": "data:image/jpeg;base64,AA=="},
+                },
+            ],
+        }
+
+        with patch("services.workflow_router.AsyncOpenAI", FakeClient):
+            selected = await router.select_edge(
+                node_name="采集车牌",
+                node_prompt="确认车牌照片是否清晰",
+                edges=[{"id": "confirm", "data": {"condition": "车牌清晰"}}],
+                history=[
+                    {"role": "user", "message": "之前的消息"},
+                    {"role": "user", "message": "请检查车牌照片"},
+                ],
+                variables={},
+                edge_name=lambda _edge: "goto_confirm",
+                edge_description=lambda _edge: "车牌清晰",
+                current_user_message=image_message,
+            )
+
+        self.assertEqual(selected.status, RouteStatus.MATCHED)
+        content = requests[0]["messages"][1]["content"]
+        self.assertIsInstance(content, list)
+        self.assertEqual(content[-1], image_message["content"][-1])
+        self.assertIn("之前的消息", content[0]["text"])
+        self.assertEqual(content[0]["text"].count("请检查车牌照片"), 0)
+
 
 if __name__ == "__main__":
     unittest.main()