nginx.conf

events {
    worker_connections 1024;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    
    # Logging
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';
    
    access_log  /var/log/nginx/access.log  main;
    error_log   /var/log/nginx/error.log;
    
    # Basic settings
    sendfile        on;
    tcp_nopush      on;
    tcp_nodelay     on;
    keepalive_timeout  65;
    types_hash_max_size 2048;
    
    # Compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types
        text/plain
        text/css
        text/xml
        text/javascript
        application/javascript
        application/json
        application/xml+rss;

    server {
        listen 8080;
        server_name localhost;
        root /usr/share/nginx/html;
        index index.html;

        # SPA settings
        location / {
            try_files $uri $uri/ /index.html;
        }

        # Proxy API requests to backend
        location /api/ {
            proxy_pass http://${BACKEND_HOST}:${BACKEND_PORT};
            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;
            
            # CORS headers
            add_header Access-Control-Allow-Origin * always;
            add_header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS" always;
            add_header Access-Control-Allow-Headers "DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization" always;
            add_header Access-Control-Expose-Headers "Content-Length,Content-Range" always;
            
            # Handle preflight requests
            if ($request_method = 'OPTIONS') {
                add_header Access-Control-Allow-Origin * always;
                add_header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS" always;
                add_header Access-Control-Allow-Headers "DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization" always;
                add_header Access-Control-Max-Age 1728000 always;
                add_header Content-Type 'text/plain; charset=utf-8' always;
                add_header Content-Length 0 always;
                return 204;
            }
        }

        # Proxy health check to backend
        location /health {
            proxy_pass http://${BACKEND_HOST}:${BACKEND_PORT}/;
            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;
        }

        # Static files caching
        location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg)$ {
            expires 1y;
            add_header Cache-Control "public, immutable";
        }

        # Security headers
        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;

        # Error handling
        error_page 404 /index.html;
        error_page 500 502 503 504 /50x.html;
        
        location = /50x.html {
            root /usr/share/nginx/html;
        }
    }
}