nginx.conf.erb

daemon off;
# Heroku dynos have at least 4 cores.
worker_processes <%= ENV['NGINX_WORKERS'] || 4 %>;

events {
  use epoll;
  accept_mutex on;
  worker_connections 1024;
}

http {
  gzip on;
  gzip_comp_level 2;
  gzip_min_length 512;

  server_tokens off;

  log_format l2met 'measure#nginx.service=$request_time request_id=$http_x_request_id';
  access_log logs/nginx/access.log l2met;
  error_log logs/nginx/error.log;

  include mime.types;
  default_type application/octet-stream;
  sendfile on;

  # Must read the body in 5 seconds.
  client_body_timeout <%= ENV['NGINX_CLIENT_BODY_TIMEOUT'] || 5 %>;

  upstream app_server {
    server unix:/tmp/nginx.socket fail_timeout=0;
  }

  server {
    listen <%= ENV["PORT"] %>;
    server_name _;
    keepalive_timeout 5;
    client_max_body_size <%= ENV['NGINX_CLIENT_MAX_BODY_SIZE'] || 1 %>M;

    location / {
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_redirect off;
      proxy_pass http://app_server;
    }
  }
}