In a previous post the AWS for PHP blog showed how to set up webhooks for handling the callbacks from their SNS messaging service. In this next part of the series they continue the process, showing how you can test these hooks locally without needing to actually send the messages. This eliminates the need to deploy to a public-facing server just to test the hooks every time you need an update.

In a recent post, I talked about Receiving Amazon SNS Messages in PHP. I showed you how to use the SNS Message and MessageValidator classes in the AWS SDK for PHP to handle incoming SNS messages. The PHP code for the webhook is easy to write, but can be difficult to test properly, since it must be deployed to a server in order to be accessible to Amazon SNS. I'll show you how you can actually test your code locally with the help of a few simple tools.

Using PHP's own built-in webserver and a tool called ngrok to tunnel from the public internet to a local server. He includes the commands to set up the PHP script directory, the code to intercept the POSTed data from the request, validate it and send the subscription confirmation request. He helps you create an SNS "topic" through the management console and walks you through a sample test request while tailing the logs.