classic-relayer/tornado.conf

# If we receive X-Forwarded-Proto, pass it through; otherwise, pass along the
# scheme used to connect to this server
map $http_x_forwarded_proto $proxy_x_forwarded_proto {
  default $http_x_forwarded_proto;
  ''      $scheme;
}
# If we receive X-Forwarded-Port, pass it through; otherwise, pass along the
# server port the client connected to
map $http_x_forwarded_port $proxy_x_forwarded_port {
  default $http_x_forwarded_port;
  ''      $server_port;
}
# If we receive Upgrade, set Connection to "upgrade"; otherwise, delete any
# Connection header that may have been passed to this server
map $http_upgrade $proxy_connection {
  default upgrade;
  '' close;
}
# Apply fix for very long server names
server_names_hash_bucket_size 128;
# Default dhparam
# Set appropriate X-Forwarded-Ssl header based on $proxy_x_forwarded_proto
map $proxy_x_forwarded_proto $proxy_x_forwarded_ssl {
  default off;
  https on;
}
gzip_types text/plain text/css application/javascript application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;
log_format vhost '$host $remote_addr - $remote_user [$time_local] '
                 '"$request" $status $body_bytes_sent '
                 '"$http_referer" "$http_user_agent" '
                 '"$upstream_addr"';
# HTTP 1.1 support
proxy_http_version 1.1;
proxy_buffering off;
proxy_set_header Host $http_host;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $proxy_connection;
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 $proxy_x_forwarded_proto;
proxy_set_header X-Forwarded-Ssl $proxy_x_forwarded_ssl;
proxy_set_header X-Forwarded-Port $proxy_x_forwarded_port;
proxy_set_header X-Original-URI $request_uri;
# Mitigate httpoxy attack (see README for details)
proxy_set_header Proxy "";

# Request rate limiting per second, 2Mb zone @ 5 requests per second
limit_req_zone $binary_remote_addr zone=one:2m rate=5r/s;
# Connections per IP limited to 2 
limit_conn_zone $binary_remote_addr zone=two:2m;

server {
	server_name _; # This is just an invalid value which will never trigger on a real hostname.
	server_tokens off;
	listen 80;
	access_log /var/log/nginx/access.log vhost;
	return 503;
}

server {
	server_name yourdomain.com;

	# Connection timeouts
	client_body_timeout 10s;
  client_header_timeout 10s;

	listen 80;
	access_log /var/log/nginx/access.log vhost;

	# Do not HTTPS redirect LetsEncrypt ACME challenge
	location ^~ /.well-known/acme-challenge/ {
    limit_req zone=one;
    limit_conn two 1;

    proxy_pass http://127.0.0.1:8000;

		break;
	}

	location / {
	  limit_req zone=one;
    limit_conn two 1;

		return 301 https://$host$request_uri;
	}

}