From 8d2e641d052dd2e2800ad9ba5f112e010dd08979 Mon Sep 17 00:00:00 2001
From: martsforever <martsforever@aliyun.com>
Date: Thu, 4 Sep 2025 23:00:41 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20has=5Femit=5Fchunk=E4=BC=98=E5=8C=96?=
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---
 app/controller/add_langgraph_chat_route.py | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/app/controller/add_langgraph_chat_route.py b/app/controller/add_langgraph_chat_route.py
index 14c74fd..536e715 100644
--- a/app/controller/add_langgraph_chat_route.py
+++ b/app/controller/add_langgraph_chat_route.py
@@ -86,8 +86,14 @@ def add_langgraph_chat_route(app: FastAPI):
     async def generator_function():
 
       graph = await ChatAgent.get_agent()
+
       # chat_state = await ChatAgent.get_chat_state(thread_id)
       # chat_history_list = chat_state.get('messages')
+
+      # has_emit_chunk 用来优化流式传输，避免将content为空的为AIMessageChunk发送给前端（实际上此时正在输出思考内容）
+      # 第一次的时候输出，后续再输出content为空的AIMessageChunk不发送给前端
+      has_emit_chunk = False
+
       async for chunk in graph.astream(
         stream_input,
         config=stream_config,
@@ -108,7 +114,8 @@ def add_langgraph_chat_route(app: FastAPI):
           # messages模式流式输出，此时 chunk[1][0] 为AIMessageChunk
           chunk_message = chunk[1][0]
           if not chunk_message.content:
-            continue
+            if has_emit_chunk:
+              continue
         else:
           # updates模式流式输出
           for k, v in chunk[1].items():
@@ -125,6 +132,7 @@ def add_langgraph_chat_route(app: FastAPI):
           "msg_type": chunk_message.type,
           "msg_content": chunk_message.content,
         }
+        has_emit_chunk = True
 
         if isinstance(chunk_message, AIMessage):
           if chunk_message.tool_calls: