所以,总结一下这个问题。完全控制加载到浏览器中的资源的最佳方法似乎是使用nsIContentPolicy。
@WladimirPalant在这里写了一个很好的例子。这就是他的代码适应 Addon SDK (v1.9) 的样子:
const { Cc, Ci, Cu, Cm, components } = require('chrome');
const { XPCOMUtils } = Cu.import("resource://gre/modules/XPCOMUtils.jsm");
let policy =
{
classDescription: "Test content policy",
classID: components.ID("{12345678-1234-1234-1234-123456789abc}"),
contractID: "@adblockplus.org/test-policy;1",
xpcom_categories: ["content-policy"],
init: function()
{
let registrar = Cm.QueryInterface(Ci.nsIComponentRegistrar);
registrar.registerFactory(this.classID, this.classDescription, this.contractID, this);
let catMan = Cc["@mozilla.org/categorymanager;1"].getService(Ci.nsICategoryManager);
for each (let category in this.xpcom_categories)
catMan.addCategoryEntry(category, this.contractID, this.contractID, false, true);
},
// nsIContentPolicy interface implementation
shouldLoad: function(contentType, contentLocation, requestOrigin, node, mimeTypeGuess, extra)
{
dump("shouldLoad: " + contentType + " " +
(contentLocation ? contentLocation.spec : "null") + " " +
(requestOrigin ? requestOrigin.spec : "null") + " " +
node + " " +
mimeTypeGuess + "\n");
return Ci.nsIContentPolicy.ACCEPT;
},
shouldProcess: function(contentType, contentLocation, requestOrigin, node, mimeTypeGuess, extra)
{
dump("shouldProcess: " + contentType + " " +
(contentLocation ? contentLocation.spec : "null") + " " +
(requestOrigin ? requestOrigin.spec : "null") + " " +
node + " " +
mimeTypeGuess + "\n");
return Ci.nsIContentPolicy.ACCEPT;
},
// nsIFactory interface implementation
createInstance: function(outer, iid)
{
if (outer)
throw Cr.NS_ERROR_NO_AGGREGATION;
return this.QueryInterface(iid);
},
// nsISupports interface implementation
QueryInterface: XPCOMUtils.generateQI([Ci.nsIContentPolicy, Ci.nsIFactory])
};
policy.init();