Caddy Unable Reverse Proxy Server Websocket Response Back To Client Side

[jerrychong25]

Hi all,

I would like to reverse proxy client incoming websocket request to HTTP Backend (Node.js App) and vice versa (HTTP Backend websocket request to client side)

I've verified the HTTP Backend that Node.js App is returning correct response back to Caddy server. Also I've tried without Caddy server and Node.js App is responding websocket correctly without any errors.

Unfortunately Caddy server returns 400 Bad Request back to client side on same flow.

How could we resolve this issue since reverse proxy handles all these traffic in background?

I'm using Docker version with following Docker Compose configuraitons:

  https-proxy:
    image: caddy:2.5.2-alpine
    container_name: caddy-https-proxy
    restart: always
    depends_on:
      - proxy
    command: caddy reverse-proxy --from proxy.mydomain.com --to nodejs_app:3000
    volumes:
      - caddy_data:/data
      - caddy_config:/config
    ports:
      - "80:80"
      - "443:443"
    networks:
      - proxy_network

Similar issues:

• https://github.com/caddyserver/caddy/issues/3648
• https://stackoverflow.com/questions/45272963/reverse-proxy-for-web-sockets-wss-using-caddy

Thanks in advance!

[francislavoie]

Duplicate of https://github.com/caddyserver/caddy/issues/4957