Function websocket

examples/wsecho.py:20–75

(request)

@Request.application
def websocket(request):
    # The underlying socket must be provided by the server. Gunicorn and
    # Werkzeug's dev server are known to support this.
    stream = request.environ.get("werkzeug.socket")

    if stream is None:
        stream = request.environ.get("gunicorn.socket")

    if stream is None:
        raise InternalServerError()

    # Initialize the wsproto connection. Need to recreate the request
    # data that was read by the WSGI server already.
    ws = WSConnection(ConnectionType.SERVER)
    in_data = b"GET %s HTTP/1.1\r\n" % request.path.encode("utf8")

    for header, value in request.headers.items():
        in_data += f"{header}: {value}\r\n".encode()

    in_data += b"\r\n"
    ws.receive_data(in_data)
    running = True

    while True:
        out_data = b""

        for event in ws.events():
            if isinstance(event, WSRequest):
                out_data += ws.send(AcceptConnection())
            elif isinstance(event, CloseConnection):
                out_data += ws.send(event.response())
                running = False
            elif isinstance(event, Ping):
                out_data += ws.send(event.response())
            elif isinstance(event, TextMessage):
                # echo the incoming message back to the client
                if event.data == "quit":
                    out_data += ws.send(
                        CloseConnection(CloseReason.NORMAL_CLOSURE, "bye")
                    )
                    running = False
                else:
                    out_data += ws.send(Message(data=event.data))

        if out_data:
            stream.send(out_data)

        if not running:
            break

        in_data = stream.recv(4096)
        ws.receive_data(in_data)

    # The connection will be closed at this point, but WSGI still
    # requires a response.
    return Response("", status=204)