Nginx Reverse Proxy & SSL Generator

server {
    listen 80;
    listen [::]:80;
    server_name example.com www.example.com;

    # Let's Encrypt HTTP-01 验证目录（certbot --webroot 模式需要）
    location /.well-known/acme-challenge/ {
        root /var/www/letsencrypt;
    }

    # 全站 80 → 443 跳转（强制 HTTPS）
    location / {
        return 301 https://$host$request_uri;
    }
}

server {
    listen 443 ssl;
    listen [::]:443 ssl;
    # 新版 Nginx(≥1.25) 推荐改为：listen 443 ssl; http2 on;
    http2 on;
    server_name example.com www.example.com;

    # SSL 证书（certbot 申请后会自动生成以下路径）
    ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
    include /etc/letsencrypt/options-ssl-nginx.conf;  # 安全协议/套件
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

    # 基础安全响应头
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    # 上传体积上限（解决 413 Request Entity Too Large）
    client_max_body_size 100M;

    # Gzip 压缩
    gzip on;
    gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript image/svg+xml;
    gzip_min_length 1024;
    gzip_comp_level 5;
    gzip_vary on;

    location / {
        proxy_pass http://127.0.0.1:3000;
        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;

        # WebSocket 支持（map 指令见下方 HTTP 上下文片段）
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $connection_upgrade;
        proxy_connect_timeout 10s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
    }
}