user  nginx;
worker_processes  auto;  # Matches number of available CPU cores

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

# Optimize for production
worker_rlimit_nofile 65535;

events {
    worker_connections  4096;
    use epoll;
    multi_accept on;
}

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    # Logging format
    log_format combined '$remote_addr - $remote_user [$time_local] '
                        '"$request" $status $body_bytes_sent '
                        '"$http_referer" "$http_user_agent" '
                        'rt=$request_time uct="$upstream_connect_time" uht="$upstream_header_time" urt="$upstream_response_time"';

    access_log  /var/log/nginx/access.log  combined;

    # Performance
    sendfile        on;
    tcp_nopush      on;
    tcp_nodelay     on;
    keepalive_timeout  75;
    keepalive_requests 1000;
    types_hash_max_size 2048;
    server_tokens off;  # Don't leak nginx version

    # Rate limiting zone (used in fashionistar.conf)
    limit_req_zone $binary_remote_addr zone=api_limit:10m rate=60r/m;
    limit_conn_zone $binary_remote_addr zone=conn_limit:10m;
    limit_conn conn_limit 20;

    # Buffer sizes
    client_body_buffer_size     128k;
    client_max_body_size        50m;
    client_header_buffer_size   1k;
    large_client_header_buffers 4 4k;
    output_buffers              1 32k;
    postpone_output             1460;

    # Proxy settings
    proxy_headers_hash_max_size 512;
    proxy_headers_hash_bucket_size 128;

    include /etc/nginx/conf.d/*.conf;
}