Webhook Response Server

These scripts will enable you to quickly get a simple HTTP server up and running so that you can register a URL with a webhook service and capture the response and potentially respond to it (if desired)

Pre-requisites

• A server reachable from the external web service

  • See ./xinet.d/webhook for ways to whitelist the service's IP address
  • If you want to run your service locally, you'll need to be able forward a port from a remote, publically addressable server.
    • Use ssh remote port forwarding. Example: ssh -R 0.0.0.0:50000:127.0.0.1:10000 ec2-54-173-251-97.compute-1.amazonaws.com
      • 50000 is the port on the server
      • 10000 is the port on your local machine (configured in your xinitd service)
      • Provide this hostname and server port to the external webhook service
      • The forwarding will be active as long as the ssh connection is intact
    • You must have added the line GatewayPorts yes to /etc/ssh/sshd_config

• The following programs must be installed on the server

  • xinetd
  • netcat (the nc command), for testing

Setup

• Run the install script and provide your override values
  • ./install -n <hook name> -p <port - default:10000> -u <user - default:webhook> -e <handler - optional>
  • Bounce your xinetd service to pick up the changes
    • It may be helpful to enable the /etc/xinetd.d/services service
    • Then you can run nc 127.0.0.1 9098 to see the list of active xinetd services
• Ensure the user has permission to execute the ./server script and the handler program (if provided)

Developing/Testing

These scripts log to /var/log/syslog under the xinetd.webhook-<hook name> tag.

Local Testing (no server xinetd service required)

Run ./test/test-local -n <hook name> to simulate a request without involving the xinetd service. This will directly invoke the ./server script with ./test/sample-http-post (or you can pipe your own request to the script instead)

Server Testing

Run ./test/test-remote <host> <port> to run the request through the xinetd service. It's probably best to test against 127.0.0.1 before running through the external hostname/IP.