[Python] Pass SocketIO server instance to FastAPI routers as dependency

I'm using python-socketio and trying to pass the server instance to my app routers as dependency:

main.py file:

import socketio
import uvicorn
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from src.api.rest.api_v1.route_builder import build_routes

app = FastAPI()
app.add_middleware(
CORSMiddleware,
allow_credentials=True,
allow_methods=["*"],
)

sio = socketio.AsyncServer(cors_allowed_origins="*", async_mode="asgi")
app = build_routes(app)
sio_asgi_app = socketio.ASGIApp(sio, app)

@app.get("/")
async def root():
return {"message": "Hello from main server !"}


def start_server():
api_port = "0.0.0.0"
api_host = "8000"
uvicorn.run(
"src.api.main:sio_asgi_app",
host=api_host,
port=int(api_port),
log_level="info",
reload=True,
)


if __name__ == "__main__":
start_server()


product_routes.py file:

from typing import Annotated
import socketio
from fastapi import APIRouter, Depends

router = APIRouter(prefix="/products")


@router.get("/emit")
async def emit_message(
sio: Annotated[socketio.AsyncServer, Depends()]
) -> None:
await sio.emit("reply", {"message": "Hello from server !"})


build_routes.py file:

def build_routes(app: FastAPI) -> FastAPI:
app.include_router(
r_products,
prefix="/v1",
dependencies=[Depends(socketio.AsyncServer)],
)
return app


So at this point I'm not sure how to pass that dependency to the routes.

When I hit the emit endpoint I get this error response:

{
"detail": [
{
"type": "missing",
"loc": [
"query",
"kwargs"
],
"msg": "Field required",
"input": null,
"url": "https://errors.pydantic.dev/2.5/v/missing"
}
]
}

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