ssjs_GetPostData.js

/*
	Great Adam Spriggs suggestion...
	https://salesforce.stackexchange.com/questions/145037/developing-and-testing-cloudpages
	
	...is to use TreatAsContent() to bypass the CloudPage caching
	%%=TreatAsContent(HttpGet(Concat("https://www.domain.com/your/webhook.html?x=",GUID())))=%%
*/

<script runat="server">
Platform.Load("core","1.1.1");

/*
	Example that handles JSON data POSTed to this page.
	e.g '{"firstname":"Joe","lastname":"Bloggs"}'
*/

var jsonPost, jsonData;

//Use JSON in post content
jsonPost = Platform.Request.GetPostData();

if (jsonPost.substring(0, 1) != '-') {
	// Parse JSON
	jsonData = Platform.Function.ParseJSON(jsonPost);
	var FirstName = jsonData.firstname;
	var LastName = jsonData.lastname;
	
	Write("Hello " + FirstName + " " + LastName);
	// Hello Joe Bloggs
}

</script>