Hi, I am trying to add WebSocket `permessage-deflate` extension support to my django channels consumer. As I know if a WebSocket server supports an extension (which was provided in the request headers), the server has to include the extension headers in the handshake response. Which I was not able to do.
The default accept() method implementation of AsyncWebsocketConsumer does not have headers parameter: https://github.com/django/channels/blob/master/channels/generic/websocket.py#L184 However, the asgiref specification states that websocket.accept message can have "headers" section: https://asgi.readthedocs.io/en/latest/specs/www.html#accept-send-event So when a client initiates WebSocket connection with "Sec-WebSocket-Extensions: permessage-deflate" headers, I use this code to accept the connection: class MyConsumer(AsyncWebsocketConsumer): async def connect(self): await self.base_send({ "type": "websocket.accept", "subprotocol": None, "headers": [ (b'sec-websocket-extensions', b'permessage-deflate') ] }) Connection gets upgraded to WS protocol, however the client does not receive the Sec-Websocket-Extensions headers and does not expect messages to be compressed. For example I am providing request/response headers. Request headers: GET ws://localhost:8080/ws/my_route/ HTTP/1.1 Host: localhost:8080 Connection: Upgrade Pragma: no-cache Cache-Control: no-cache User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.97 Safari/537.36 Upgrade: websocket Origin: http://localhost:8200 Sec-WebSocket-Version: 13 Accept-Encoding: gzip, deflate, br Accept-Language: en-US,en;q=0.9 Sec-WebSocket-Key: XXXXXXXXXXXXXXXXXXXXXX== Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits Response headers: HTTP/1.1 101 Switching Protocols Server: Daphne Upgrade: WebSocket Connection: Upgrade Sec-WebSocket-Accept: XXXXXXXXXXXXXXXXXXXXXXXXXXX= This behaviour is observed when using manage.py runserver on RedHat7 linux and newest Chrome/Firefox browsers. Main package from my pip freeze are: aiohttp==3.6.2 aioredis==1.2.0 asgiref==3.2.9 async-timeout==3.0.1 asyncio==3.4.3 billiard==3.6.0.0 channels==2.4.0 channels-redis==2.4.0 daphne==2.3.0 Django==2.2 django-cors-headers==2.3.0 django-crequest==2018.5.11 gunicorn==19.9.0 pika==0.12.0 redis==3.2.1 tornado==5.1 Twisted==18.9.0 txaio==18.8.1 urllib3==1.24.1 I am not sure whether its a bug, or am I doing something wrong? Best regards, Albertas -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/8e346f91-ed71-4ce0-97bb-d83a72f4409fo%40googlegroups.com.
