前端修改

app/agent.py

@@ -137,7 +137,10 @@ class AIAgentService:
                 raise RuntimeError(f"错误: 没有任何可用的模型。当前注册的模型: {list(self.graphs.keys())}")
 
         graph = self.graphs[model]
-        config = {"configurable": {"thread_id": thread_id}}
+        config = {
+            "configurable": {"thread_id": thread_id},
+            "metadata": {"user_id": user_id}  # 写入 metadata 供历史查询使用
+        }
         input_state = {"messages": [{"role": "user", "content": message}]}
         context = GraphContext(user_id=user_id)
         
@@ -152,3 +155,63 @@ class AIAgentService:
             "token_usage": token_usage,
             "elapsed_time": elapsed_time
         }
+    
+    async def process_message_stream(self, message: str, thread_id: str, model_name: str, user_id: str = "default_user"):
+        """
+        流式处理消息，返回异步生成器
+        
+        Args:
+            message: 用户消息
+            thread_id: 线程 ID
+            model_name: 模型名称
+            user_id: 用户 ID
+            
+        Yields:
+            字典，包含事件类型和数据
+        """
+        graph = self.graphs.get(model_name)
+        if not graph:
+            warning(f"警告: 模型 '{model_name}' 不可用，使用默认模型")
+            model_name = next(iter(self.graphs.keys()))
+            graph = self.graphs[model_name]
+        
+        config = {
+            "configurable": {"thread_id": thread_id},
+            "metadata": {"user_id": user_id}
+        }
+        input_state = {"messages": [{"role": "user", "content": message}]}
+        context = GraphContext(user_id=user_id)
+        
+        # 使用 astream_events 获取流式事件
+        async for event in graph.astream_events(input_state, config=config, context=context, version="v2"):
+            kind = event["event"]
+            
+            # 聊天模型流式输出
+            if kind == "on_chat_model_stream":
+                content = event["data"]["chunk"].content
+                if content:
+                    yield {"type": "token", "content": content}
+            
+            # 工具调用开始
+            elif kind == "on_tool_start":
+                tool_name = event["name"]
+                yield {"type": "tool_start", "tool": tool_name}
+            
+            # 工具调用结束
+            elif kind == "on_tool_end":
+                tool_name = event["name"]
+                yield {"type": "tool_end", "tool": tool_name}
+            
+            # 链结束，获取最终结果
+            elif kind == "on_chain_end" and event["name"] == "LangGraph":
+                output = event["data"]["output"]
+                reply = output["messages"][-1].content if output.get("messages") else ""
+                token_usage = output.get("last_token_usage", {})
+                elapsed_time = output.get("last_elapsed_time", 0.0)
+                
+                yield {
+                    "type": "done",
+                    "reply": reply,
+                    "token_usage": token_usage,
+                    "elapsed_time": elapsed_time
+                }