The javascript to populate the portlet. JQuery is available as 'Q' and console.log() is ensured to work even in IE. The js is called in a function context with variables defined:

• divId: The id of an empty div content can be written to with jquery
• rootUrl: The jenkins root url
• ajaxViaJenkins: a function to proxy ajax requests via jenkins in order to avoid the cross domain security restrictions (see https://wiki.jenkins-ci.org/display/JENKINS/AJAX+with+JavaScript+proxy for implementation details). The first argument is the url, as a second and third argument credentials can be passed in (optional). The last argument is the callback function that receives the response object.

Examples
// Google Search Form
var googleUrl = 'http://www.google.com';
Q('#'+divId).html('Loading google home page result...');
ajaxViaJenkins(googleUrl, function(resp) {
   Q('#'+divId).html('Processing response (link rewriting, replacing this content)...');
   var responseText = resp.responseText.replace(/(\/search)/g, googleUrl + '$1');
   var responseDom = Q("<div>").append(responseText);
   Q('#'+divId).html( responseDom.find("form").first());
});

// Load JSON from API with authentication
var url = 'http://myservice.intranet/api/rest';
Q('#'+divId).html('Loading portlet...');
ajaxViaJenkins(url, "myuser", "password", function(resp) {
   var jsonObject = resp.responseObject();
   ...
});