Nginx lethe.it conf - cache, sockets, gzip

nginx.lethe.conf

roxy_cache_path  /var/cache/nginx/cache levels=1:2 keys_zone=cache:8m max_size=3000m inactive=600m;
proxy_temp_path /var/tmp;

log_format rt_cache '$remote_addr - $upstream_cache_status [$time_local]  '
                    '"$request" $status $body_bytes_sent '
                    '"$http_referer" "$http_user_agent"';

server {
       listen         80;
       server_name    lethe.it;
       return         301 https://$server_name$request_uri;
}

server {
  access_log /var/log/nginx/lethe-it.access.log rt_cache;

  listen       443 ssl;
  server_name  lethe.it;

  ssl_certificate      /etc/ssl/certs/ssl-cert-snakeoil.pem;
  ssl_certificate_key  /etc/ssl/private/ssl-cert-snakeoil.key;

  # enable session resumption to improve https performance
  # http://vincent.bernat.im/en/blog/2011-ssl-session-reuse-rfc5077.html
  ssl_session_cache shared:SSL:50m;
  ssl_session_timeout 5m;

  # gzip on;
  # gzip_comp_level 6;
  # gzip_vary on;
  # gzip_min_length  1000;
  # gzip_proxied any;
  # gzip_types text/plain text/html text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;
  # gzip_buffers 16 8k;

  location / {
    proxy_pass http://localhost:3000;
    proxy_redirect off;
    proxy_http_version 1.1;

    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-NginX-Proxy     true;
    proxy_set_header Host              $host;

    proxy_cache cache;
    # proxy_ignore_headers "Cache-Control" "Expires";
    # proxy_cache_key $scheme$proxy_host$uri$is_args$args;
    # proxy_cache_key "$scheme://$host$request_uri";
    proxy_cache_valid 200 302 1d;
    proxy_cache_use_stale  error timeout invalid_header updating http_500 http_502 http_503 http_504;

    # proxy_cache_bypass   $http_secret_header;
    # add_header X-Cache-Status $upstream_cache_status;

    add_header Cache-Control "public";

    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_cache_bypass $http_upgrade;
  }

  location /public {
    root /www/lethe.it/public;
  }