Node.js (Express)

map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
}

upstream nodejs_backend {
    server 127.0.0.1:3000;
    keepalive 32;
}

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

server {
    listen 443 ssl http2;
    listen [::]:443 ssl http2;
    server_name example.com;

    ssl_certificate     /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 1d;

    server_tokens off;
    client_max_body_size 10m;

    access_log /var/log/nginx/nodejs-access.log combined;
    error_log  /var/log/nginx/nodejs-error.log warn;

    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;

    gzip on;
    gzip_comp_level 5;
    gzip_types text/plain text/css application/json application/javascript image/svg+xml;

    # Статика мимо Node.js
    location /public/ {
        alias /var/www/app/public/;
        expires 30d;
        add_header Cache-Control "public, immutable";
    }

    # WebSocket
    location /ws/ {
        proxy_pass http://nodejs_backend;
        proxy_http_version 1.1;
        proxy_set_header Upgrade    $http_upgrade;
        proxy_set_header Connection $connection_upgrade;
        proxy_set_header Host       $host;
        proxy_set_header X-Real-IP  $remote_addr;
        proxy_read_timeout 3600s;
        proxy_buffering off;
    }

    location / {
        proxy_pass http://nodejs_backend;
        proxy_http_version 1.1;
        proxy_set_header Host              $host;
        proxy_set_header X-Real-IP         $remote_addr;
        proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Connection        "";
        proxy_read_timeout 60s;
    }

    location ~ /\. { deny all; }

    error_page 500 502 503 504 /50x.html;
    location = /50x.html { root /usr/share/nginx/html; }
}