GraphQLTransportWSHandler not working?

[fdemian]

Hi, I'm using Ariadne on my application and so far everything seems to be working normally, but recently the websocket handlers seem to have stopped working.
This is the code I'm using

Here's my pyproject.toml (list of packages):

[tool.poetry]
name = "testapp"
version = "0.1.0"
description = ""
authors = ["user <[email protected]>"]
license = "BSD-2"
packages = [
  { include="api", from="." }
]

[tool.poetry.dependencies]
python = "^3.10"
ariadne = "=0.16.1"
alembic = "1.8.1"
psycopg2-binary = "2.9.4"
PyJWT = "^2.3.0"
starlette = "0.20.4"
"marrow.mailer" = "^4.0.3"
gunicorn = "^20.1.0"
python-multipart = "^0.0.5"
SQLAlchemy = "1.4.42"
rauth = "^0.7.3"
aiohttp = "3.8.3"
aiofiles = "22.1.0"
SQLAlchemy-Utils = "^0.38.3"
BroadCast = "^1.1.2"
uvicorn = {extras = ["standard"], version = "^0.19.0"}
broadcaster = {extras = ["postgres"], version = "^0.2.0"}
websockets = "^10.3"
graphql-core = "3.2.3"

[tool.poetry.scripts]
init_app = "api.scripts.initial_config:main"

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

Im running the following code using poetry ( poetry run python3 main.py )

import uvicorn
import asyncio
from ariadne.asgi import GraphQL
from ariadne.asgi.handlers import GraphQLTransportWSHandler
from ariadne import MutationType, make_executable_schema
from starlette.applications import Starlette
from starlette.routing import WebSocketRoute

type_defs = """
  type Query {
    _unused: Boolean
  }

  type Message {
    sender: String
    message: String
  }

  type Mutation {
    send(sender: String!, message: String!): Boolean
  }

  type Subscription {
    message: Message
  }
"""

mutation = MutationType()
schema = make_executable_schema(type_defs, mutation)
graphql_handler = GraphQL(
  schema=schema,
  debug=True,
  websocket_handler=GraphQLTransportWSHandler(),
  logger="admin.graphql"
)

routes = [
  WebSocketRoute("/api/graphqlws", endpoint=graphql_handler),
]

app = Starlette(routes=routes)


async def main():
    config = uvicorn.Config("main:app", port=8000, log_level="info")
    server = uvicorn.Server(config)
    await server.serve()

if __name__ == "__main__":
    asyncio.run(main())

When I try to open a new websocket connection (opening a new browser window and using new WebSocket('ws://localhost:8000/api/graphqlws'); ).

it does not seem to be working. This is the output I'm seeing:

Database URL already set
postgresql+psycopg2://postgres:postgres@localhost:5432/reactivebb
INFO:     Started server process [6869]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
INFO:     ('127.0.0.1', 63746) - "WebSocket /api/graphqlws" [accepted]
INFO:     connection open
INFO:     connection closed

Is there something I'm doing wrong?
Note: running this without the following lines

async def main():
    config = uvicorn.Config("main:app", port=8000, log_level="info")
    server = uvicorn.Server(config)
    await server.serve()

if __name__ == "__main__":
    asyncio.run(main())

And using poetry run uvicorn main:app produces the same output.
I also have this problem on a larger application I'm building, which uses apollo and graphql but I'm guessing this is the same problem.