Rapid Web Applications with TurboGears: Using Python to Create Ajax-Powered Sites

Chapter 15.1.2. Making a Request

Let’s say that you’re not out to do anything too fancy. You just want to run a simple XMLHttpRequest to get some more data from the server. Here’s how you do that:

function showText(xmlhttp) {
    alert(xmlhttp.responseText);
}
d = doSimpleXMLHttpRequest("http://localhost:8080/yourcode");
d.addCallback(showText);

That’s some easy Ajax.

doSimpleXMLHttpRequest returns a Deferred. By making the call, we know that the XMLHttpRequest was made, but we have no idea when it will return. We just have the promise that we will either get a result or an error condition after the browser has finished with the asynchronous request.

By calling addCallback on the Deferred, we tell MochiKit where in our JavaScript code the ...