Example nginx configs with Rails 5.1 API only server

nginx.conf

# Configure the reverse-proxy on port 443
# Supports CORS
# check it by running nginx -t -c nginx.conf
# restart nginx by runnging sudo service nginx restart

server {
  # general configs
  keepalive_timeout    30;
  listen               127.0.0.1:443 ssl;
  server_name          api.example.com; # domain name goes here

  # ssl configs
  ssl_certificate      /path/to/api.crt; # could also be .cer file must be apple compliant
  ssl_certificate_key  /path/to/api.key; #
  ssl_session_cache    shared:SSL:10m;
  ssl_session_timeout  10m;

  # proxy to the rails API
  location / {
    # proxy to the rails application
    client_max_body_size 8M;
    proxy_pass   http://127.0.0.1:3000;
    
    # set additional security headers
    add_header 'Cache-Control'                    'no-cache, no-store, must-revalidate';
    add_header 'Content-Security-Policy'          'connect-src example.com';
    add_header 'Expires'                          '0';
    add_header 'Pragma'                           'no-cache';
    add_header 'Strict-Transport-Security'        'max-age=31536000; includeSubDomains';
    add_header 'X-Content-Type-Options'           'nosniff';
    add_header 'X-Frame-Options'                  'DENY';
    add_header 'X-XSS-Protection'                 '1; mode=block';
  }

  # logs paths
  access_log /path/to/access.log;
  error_log  /path/to/error.log;
}

# Rewrite all trafic on port 80 to 443
server {
  listen         127.0.0.1:80;
  server_name    api.example.com;
  rewrite        ^ https://$server_name:3000$request_uri? permanent;
}