When drone is deployed behind nginx, the websocket support is broken even if nginx is configured as per http://readme.drone.io/setup/misc/nginx/

After some debugging, I found the problem is that gorilla/websocket library by default checks whether the Host header matches the Origin header, and return a 403 Forbidden when they don't match. When using nginx, the Origin header is the external url, and the Host header is the address drone is listening on, so they differ and the browser get a 403 for websocket requests.

The correspondent code is here .

A temporary hack is to set the origin header to an empty string in nginx configration, e.g:

    location /api/stream {
        proxy_pass http://127.0.0.1:8000;

        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $http_connection;

        proxy_set_header Origin '';
    }

The above hack works for me, but I hope we can find a more elegant solution for this.