Coder running on Laravel Forge can not connect to Websocket endpoint - docker

Question

I've configured Coder and followed this instructions to set it up via Docker Compose.
In order to be able to use a public domain, I've configured a reverse proxy with nginx. Everything works except for the websocket connection which is used to get logs, status updates etc etc.
The error is: wss://workspaces.mydomain.io/api/private/workspaces/623ae5f6-0e4817996a28f4e5e592cb87/watch-stats' failed
The server is managed via Laravel Forge.
Here is my docker-compose.yml:
version: "3.5"
services:
coder:
image: docker.io/codercom/coder:1.28.2
container_name: coderd
restart: unless-stopped
ports:
- 7080:7080/tcp
volumes:
- /var/run/docker.sock:/var/run/docker.sock
- ${HOME}/.coder:/var/run/coder
environment:
DEVURL_HOST: "*.workspaces.mydomain.io"
And here my nginx configuration:
server {
listen 80;
listen [::]:80;
server_name .workspaces.mydomain.io;
server_tokens off;
root /home/forge/workspaces.mydomain.io/coder/public;
# FORGE SSL (DO NOT REMOVE!)
# ssl_certificate;
# ssl_certificate_key;
ssl_protocols TLSv1.2 TLSv1.3;
ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
ssl_prefer_server_ciphers off;
ssl_dhparam /etc/nginx/dhparams.pem;
add_header X-Frame-Options "SAMEORIGIN";
add_header X-XSS-Protection "1; mode=block";
add_header X-Content-Type-Options "nosniff";
index index.html index.htm index.php;
charset utf-8;
# FORGE CONFIG (DO NOT REMOVE!)
include forge-conf/workspaces.mydomain.io/server/*;
location / {
proxy_pass http://127.0.0.1:7080;
}
location = /favicon.ico { access_log off; log_not_found off; }
location = /robots.txt { access_log off; log_not_found off; }
access_log off;
error_log /var/log/nginx/workspaces.mydomain.io-error.log error;
error_page 404 /index.php;
location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php/php8.1-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
}
location ~ /\.(?!well-known).* {
deny all;
}
}