Add Tutorial around using tegola behind a proxy

[ARolek]

Not all deployments of tegola allow for binding to a specific port. Nginx and HAProxy are often used in front of tegola. It would be nice to have some tutorial documentation around this.

[brightrain]

Happy to share the nginx config that we got working (ht @ARolek for the help here). This is the nginx site configuration that is working for us. The main site is being served from our domain root and we are also serving out vector tiles from tegola on localhost:8080 and making them available via our domain at:

example.com/tiles

config using example.com as the domain

server {
        listen 80;
        listen [::]:80;

        root /var/www/example/html;
        index index.html index.htm index.nginx-debian.html;

        server_name example.com www.example.com;

        location / {
                alias /var/www/example/html/public/;
                try_files $uri $uri/ =404;
        }
       
        location /tiles/ {
            proxy_pass http://127.0.0.1:8080/;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection 'upgrade';
            proxy_set_header Host $host;
            proxy_cache_bypass $http_upgrade;
        }
}

FYI for anyone doing this, that last slash in the proxy_pass property value turned out to be the critical piece