nginx.conf.example

server {
    listen 80;
    server_name example.com;
    
    # Redirect HTTP to HTTPS
    return 301 https://$host$request_uri;
}

server {
    listen 443 ssl;
    server_name example.com;
    
    # SSL configuration
    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_prefer_server_ciphers on;
    ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384;
    ssl_session_timeout 1d;
    ssl_session_cache shared:SSL:10m;
    
    # Security headers
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "DENY" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header Content-Security-Policy "default-src 'self'; connect-src 'self' https://example.com http://localhost:3001 https://*.example.com; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; font-src 'self' data:;" always;
    
    # Frontend (Next.js)
    location / {
        proxy_pass http://localhost:3000;  # Assuming Next.js runs on port 3000
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        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 X-Forwarded-Host $host;
        proxy_cache_bypass $http_upgrade;
    }
    
    # Backend API (FastAPI)
    location /api/ {
        proxy_pass http://localhost:3001;  # Assuming FastAPI runs on port 3001
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        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 X-Forwarded-Host $host;
        proxy_cache_bypass $http_upgrade;
        
        # CORS headers for preflight requests
        if ($request_method = 'OPTIONS') {
            add_header 'Access-Control-Allow-Origin' '*' always;
            add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, OPTIONS, PATCH' always;
            add_header 'Access-Control-Allow-Headers' 'Content-Type, Authorization, X-Requested-With, X-CSRF-Token' always;
            add_header 'Access-Control-Max-Age' 86400;  # Cache preflight for 24 hours
            add_header 'Content-Type' 'text/plain charset=UTF-8';
            add_header 'Content-Length' 0;
            return 204;
        }
    }
    
    # Large file uploads
    client_max_body_size 100M;
}