ActionCable 404 error for wss with ELB and nginx - ssl

Question

I'm getting this error for actioncable when I switched my site to https:
WebSocket connection to 'wss://domain.com/cable' failed: Error during
WebSocket handshake: Unexpected response code: 404
The https site works fine, but I get a 404 for the websocket address. My current setup has the SSL terminate at the ELB and nginx redirect http to https. I run actioncable together with my rail server, not as a standalone.
How would I set up secure websockets in ?
Here is my nginx conf file
upstream puma {
server unix://var/run/server.sock;
}
server {
listen 80;
server_name default_server;
root /var/www/apps/server/public;
location /cable {
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_http_version 1.1;
proxy_set_header Host $host;
proxy_pass http://puma;
}
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_next_upstream error;
if ($http_x_forwarded_proto != "https") {
rewrite ^(.*)$ https://$host$1 permanent;
}
proxy_pass http://puma;
...
}
And here is the configuration on ELB:
ELB Listeners

Answer 1

Fixed similar error (404 in actioncable /cable) in my setup like this
location /cable {
proxy_pass http://unix:/home/app/shared/tmp/puma/socket;
proxy_http_version 1.1;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_set_header X-Forwarded-Host $host:$server_port;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_read_timeout 86400;
}
so add same proxy_set_header as you have in the other location (X-Real-IP etc)