efriis / langchain-perplexaty Goto Github PK

I followed through the youtube tutorial, while the Langsmith traces show no errors and reflects an expected output, there is no output in the playground after I hit "start" in a local run. The following is the stack trace of the error generated in the langchain cli:

INFO: 127.0.0.1:55788 - "POST /search/stream_log HTTP/1.1" 200 OK
ERROR: Exception in ASGI application
Traceback (most recent call last):
File "/usr/local/lib/python3.9/site-packages/uvicorn/protocols/http/h11_impl.py", line 404, in run_asgi
result = await app( # type: ignore[func-returns-value]
File "/usr/local/lib/python3.9/site-packages/uvicorn/middleware/proxy_headers.py", line 84, in call
return await self.app(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/fastapi/applications.py", line 1106, in call
await super().call(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/starlette/applications.py", line 122, in call
await self.middleware_stack(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/starlette/middleware/errors.py", line 184, in call
raise exc
File "/usr/local/lib/python3.9/site-packages/starlette/middleware/errors.py", line 162, in call
await self.app(scope, receive, _send)
File "/usr/local/lib/python3.9/site-packages/starlette/middleware/exceptions.py", line 79, in call
raise exc
File "/usr/local/lib/python3.9/site-packages/starlette/middleware/exceptions.py", line 68, in call
await self.app(scope, receive, sender)
File "/usr/local/lib/python3.9/site-packages/fastapi/middleware/asyncexitstack.py", line 20, in call
raise e
File "/usr/local/lib/python3.9/site-packages/fastapi/middleware/asyncexitstack.py", line 17, in call
await self.app(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 718, in call
await route.handle(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 276, in handle
await self.app(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/starlette/routing.py", line 69, in app
await response(scope, receive, send)
File "/usr/local/lib/python3.9/site-packages/sse_starlette/sse.py", line 269, in call
await wrap(partial(self.listen_for_disconnect, receive))
File "/usr/local/lib/python3.9/site-packages/anyio/_backends/_asyncio.py", line 597, in aexit
raise exceptions[0]
File "/usr/local/lib/python3.9/site-packages/sse_starlette/sse.py", line 258, in wrap
await func()
File "/usr/local/lib/python3.9/site-packages/sse_starlette/sse.py", line 245, in stream_response
async for data in self.body_iterator:
File "/usr/local/lib/python3.9/site-packages/langserve/api_handler.py", line 1032, in _stream_log
raise AssertionError(
AssertionError: Expected a RunLog instance got <class 'langchain_core.tracers.log_stream.RunLogPatch'>

Hey! I've done the walk through , thanks for such detail and easy-to-follow explanation, kudos to @efriis 🎊

I have replicated the chain + serving it with langserve. I'd need to consume this endpoint , served with langserve, from an external app. The server is working properly, I'm able to consume /playground from my web browser, but I can't consume /invoke using postman or client app.

I've tried to follow langserve docs on the client side, but I'm facing some errors

Client code

import requests

response = requests.post(
    "http://localhost:8000/search/invoke",
    json={'input': {'topic': 'cats'}}
)
response.json()

Error:

{'detail': [{'loc': ['__root__'],
   'msg': 'str type expected',
   'type': 'type_error.str'}]}

Am I missing something? Should I use other client approach? I'd appreciate any further docs / reading.
Thanks again 😄