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ASGI Hosting

SignalRServer.asgi_app() returns a standard ASGI application that serves the negotiate / WebSocket / SSE / Long Polling / POST endpoints for your hub. Mount it inside uvicorn, FastAPI or any ASGI server.

Standalone uvicorn​

import uvicorn

from aiosignalr.server import Hub, SignalRServer


class ChatHub(Hub):
    async def echo(self, text: str) -> str:
        return text


server = SignalRServer(ChatHub)
app = server.asgi_app(path="/hub")

if __name__ == "__main__":
    uvicorn.run(app, host="127.0.0.1", port=8000)

Inside FastAPI​

from fastapi import FastAPI

from aiosignalr.server import Hub, SignalRServer


class ChatHub(Hub):
    async def echo(self, text: str) -> str:
        return text


app = FastAPI()
server = SignalRServer(ChatHub)
app.mount("/hub", server.asgi_app(path="/hub"))

The hub now lives at http://host:8000/hub.

Mounting in an existing ASGI tree​

Because asgi_app() is itself a plain ASGI app, you can compose it with any routing layer. The endpoint path is fully controlled by path.

Requirements​

  • The ASGI server must support WebSocket upgrade (uvicorn does; some production proxies need WebSocket support enabled).
  • For stateful reconnect, the underlying ASGI server must keep the connection open and allow reuse of the same connection token across reconnects (uvicorn handles this).

Note on lifecycle​

The returned app is stateless and process-local. If you need to share hub state across workers or machines, plug a custom lifetime manager — see HubLifetimeManager.