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How do I register this so I can use nsIContentPolicy shouldLoad method?
const {Cc, Ci, Cu, Cm, Cr} = require("chrome");
const xpcom = require("xpcom");
class definition
var description = "Chromeless Policy XPCOM Component";
/* UID generated by */
var classID = Components.ID("{2e946f14-72d5-42f3-95b7-4907c676cf2b}");
// I just made this up. Don't know if I'm supposed to do that.
var contractID = ";1";
//class constructor
function ChromelessPolicy() {
//this.wrappedJSObject = this;
// class definition
var ChromelessPolicy = {
// properties required for XPCOM registration:
classDescription: description,
classID: classID,
contractID: contractID,
xpcom_categories: ["content-policy"],
// QueryInterface implementation
QueryInterface: xpcom.utils.generateQI([Ci.nsIContentPolicy,
Ci.nsIFactory, Ci.nsISupportsWeakReference]),
// ...component implementation...
shouldLoad : function(aContentType, aContentLocation, aRequestOrigin, aContext, aMimeTypeGuess, aExtra) {
let result = Ci.nsIContentPolicy.ACCEPT;
// only filter DOCUMENTs (not SUB_DOCUMENTs, like iframes)
if( aContentType === Ci.nsIContentPolicy["TYPE_DOCUMENT"]
// block http(s) protocols...
&& /^http(s):/.test(aContentLocation.spec) ){
// make sure we deny the request now
result = Ci.nsIContentPolicy.REJECT_REQUEST;
// continue loading...
return result;
createInstance: function(outer, iid) {
if (outer)
return this.QueryInterface(iid);
let registrar = Cm.QueryInterface(Ci.nsIComponentRegistrar);
Cm.nsIComponentRegistrar.registerFactory(classID, description, contractID, ChromelessPolicy);
catch (e) {
// Don't stop on errors - the factory might already be registered
const categoryManager = Cc[";1"].getService(Ci.nsICategoryManager);
for each (let category in ChromelessPolicy.xpcom_categories) {
categoryManager.addCategoryEntry(category, ChromelessPolicy.classDescription, ChromelessPolicy.contractID, false, true);
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