separate chat api for multi-agent code

templates/components/multiagent/python/app/api/routers/chat.py

@@ -0,0 +1,49 @@
+import logging
+
+from app.api.routers.events import EventCallbackHandler
+from app.api.routers.models import (
+    ChatData,
+)
+from app.api.routers.vercel_response import (
+    WorkflowVercelStreamResponse,
+)
+from app.engine import get_chat_engine
+from fastapi import APIRouter, BackgroundTasks, HTTPException, Request, status
+
+chat_router = r = APIRouter()
+
+logger = logging.getLogger("uvicorn")
+
+
+# streaming endpoint - delete if not needed
+@r.post("")
+async def chat(
+    request: Request,
+    data: ChatData,
+    background_tasks: BackgroundTasks,
+):
+    try:
+        last_message_content = data.get_last_message_content()
+        messages = data.get_history_messages()
+
+        event_handler = EventCallbackHandler()
+        # The chat API supports passing private document filters and chat params
+        # but agent workflow does not support them yet
+        # ignore chat params and use all documents for now
+        # TODO: generate filters based on doc_ids
+        # TODO: use chat params
+        engine = get_chat_engine(chat_history=messages)
+
+        event_handler = engine.run(input=last_message_content, streaming=True)
+        return WorkflowVercelStreamResponse(
+            request=request,
+            chat_data=data,
+            event_handler=event_handler,
+            events=engine.stream_events(),
+        )
+    except Exception as e:
+        logger.exception("Error in chat engine", exc_info=True)
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+            detail=f"Error in chat engine: {e}",
+        ) from e