Refactor callback handler to use SocketIOService

src/backend/langflow/api/v1/callback.py

@@ -1,28 +1,32 @@
 import asyncio
-from typing import Any, Dict, List, Optional
+from typing import TYPE_CHECKING, Any, Dict, List, Optional
 from uuid import UUID
 
 from langchain.callbacks.base import AsyncCallbackHandler, BaseCallbackHandler
 from langchain.schema import AgentAction, AgentFinish
-from loguru import logger
-
 from langflow.api.v1.schemas import ChatResponse, PromptResponse
 from langflow.services.deps import get_chat_service
 from langflow.utils.util import remove_ansi_escape_codes
+from loguru import logger
+
+if TYPE_CHECKING:
+    from langflow.services.socket.service import SocketIOService
 
 
 # https://github.com/hwchase17/chat-langchain/blob/master/callback.py
 class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
     """Callback handler for streaming LLM responses."""
 
-    def __init__(self, client_id: str):
+    def __init__(self, session_id: str):
         self.chat_service = get_chat_service()
-        self.client_id = client_id
-        self.websocket = self.chat_service.active_connections[self.client_id]
+        self.client_id = session_id
+        self.socketio_service: "SocketIOService" = self.chat_service.socketio_service
+        self.sid = session_id
+        # self.socketio_service = self.chat_service.active_connections[self.client_id]
 
     async def on_llm_new_token(self, token: str, **kwargs: Any) -> None:
         resp = ChatResponse(message=token, type="stream", intermediate_steps="")
-        await self.websocket.send_json(resp.model_dump())
+        await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
 
     async def on_tool_start(self, serialized: Dict[str, Any], input_str: str, **kwargs: Any) -> Any:
         """Run when tool starts running."""
@@ -31,7 +35,7 @@ class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
             type="stream",
             intermediate_steps=f"Tool input: {input_str}",
         )
-        await self.websocket.send_json(resp.model_dump())
+        await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
 
     async def on_tool_end(self, output: str, **kwargs: Any) -> Any:
         """Run when tool ends running."""
@@ -62,7 +66,7 @@ class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
         try:
             # This is to emulate the stream of tokens
             for resp in resps:
-                await self.websocket.send_json(resp.model_dump())
+                await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
         except Exception as exc:
             logger.error(f"Error sending response: {exc}")
 
@@ -88,7 +92,7 @@ class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
             resp = PromptResponse(
                 prompt=text,
             )
-            await self.websocket.send_json(resp.model_dump())
+            await self.socketio_service.emit_message(to=self.sid, data=resp.model_dump())
             self.chat_service.chat_history.add_message(self.client_id, resp)
 
     async def on_agent_action(self, action: AgentAction, **kwargs: Any):
@@ -99,10 +103,10 @@ class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
             logs = log.split("\n")
             for log in logs:
                 resp = ChatResponse(message="", type="stream", intermediate_steps=log)
-                await self.websocket.send_json(resp.model_dump())
+                await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
         else:
             resp = ChatResponse(message="", type="stream", intermediate_steps=log)
-            await self.websocket.send_json(resp.model_dump())
+            await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
 
     async def on_agent_finish(self, finish: AgentFinish, **kwargs: Any) -> Any:
         """Run on agent end."""
@@ -111,7 +115,7 @@ class AsyncStreamingLLMCallbackHandler(AsyncCallbackHandler):
             type="stream",
             intermediate_steps=finish.log,
         )
-        await self.websocket.send_json(resp.model_dump())
+        await self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
 
 
 class StreamingLLMCallbackHandler(BaseCallbackHandler):
@@ -120,11 +124,11 @@ class StreamingLLMCallbackHandler(BaseCallbackHandler):
     def __init__(self, client_id: str):
         self.chat_service = get_chat_service()
         self.client_id = client_id
-        self.websocket = self.chat_service.active_connections[self.client_id]
+        self.socketio_service = self.chat_service.active_connections[self.client_id]
 
     def on_llm_new_token(self, token: str, **kwargs: Any) -> None:
         resp = ChatResponse(message=token, type="stream", intermediate_steps="")
 
         loop = asyncio.get_event_loop()
-        coroutine = self.websocket.send_json(resp.model_dump())
+        coroutine = self.socketio_service.emit_token(to=self.sid, data=resp.model_dump())
         asyncio.run_coroutine_threadsafe(coroutine, loop)