# Install in an nginx http-context include (e.g. sites-enabled).
# Replace game.example.com and certificate paths before enabling.
map $http_upgrade $dragon_ball_connection {
    default upgrade;
    '' close;
}
limit_req_zone $binary_remote_addr zone=dragon_ball_signal:10m rate=10r/s;

server {
    listen 80;
    server_name game.example.com;
    return 301 https://game.example.com$request_uri;
}

server {
    listen 443 ssl;
    server_name game.example.com;
    ssl_certificate /etc/letsencrypt/live/game.example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/game.example.com/privkey.pem;
    ssl_protocols TLSv1.2 TLSv1.3;
    client_max_body_size 16k;
    access_log off;

    location / {
        proxy_pass http://127.0.0.1:2100;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        # Internet-facing nginx on the app host; discard client-supplied forwarding.
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Connection "";
    }

    location /socket.io/ {
        limit_req zone=dragon_ball_signal burst=40 nodelay;
        limit_req_status 429;
        proxy_pass http://127.0.0.1:2100;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $dragon_ball_connection;
        proxy_read_timeout 75s;
        proxy_send_timeout 75s;
        proxy_buffering off;
    }
}