nginx.conf

# nginx.conf - Load balancer for scaled Netskrafl deployment
#
# Usage with docker-compose:
#   1. Uncomment the nginx service in docker-compose.yml
#   2. Change app service to use 'expose' instead of 'ports'
#   3. Run: docker-compose --profile scaled up --scale app=3
#
# This will run 3 app instances behind nginx on port 80.

events {
    worker_connections 1024;
}

http {
    # Upstream backend pool
    # Docker's internal DNS resolves 'app' to all container IPs
    upstream backend {
        server app:8080;
        # Keepalive connections to backend for better performance
        keepalive 32;
    }

    # Logging format
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for" '
                    'upstream=$upstream_addr response_time=$upstream_response_time';

    access_log /dev/stdout main;
    error_log /dev/stderr warn;

    server {
        listen 80;
        server_name _;

        # Security headers
        add_header X-Frame-Options "SAMEORIGIN" always;
        add_header X-Content-Type-Options "nosniff" always;

        # Proxy settings
        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 "";  # Enable keepalive

        # Timeouts
        proxy_connect_timeout 10s;
        proxy_send_timeout 30s;
        proxy_read_timeout 30s;

        # Main application
        location / {
            proxy_pass http://backend;
        }

        # Health check endpoint for the load balancer itself
        location /nginx-health {
            access_log off;
            return 200 'OK\n';
            add_header Content-Type text/plain;
        }

        # Static files with caching (optional optimization)
        # Uncomment if you want nginx to serve static files directly
        # location /static/ {
        #     alias /app/static/;
        #     expires 1d;
        #     add_header Cache-Control "public, immutable";
        # }
    }
}