Redirecting Request (nsiHttpChannel?) in Firefox Extensions

user_270302 0
Viewed 7175

I've been trying at this for a long time now, and no good results.

var myObserver = {
    observe: function(subject, topic, data)
    {
        if (topic == "http-on-examine-response") 
        {   
             //  implement later
        } 
        else if(topic == "http-on-modify-request") 
        {
             //  implement later
        }
   },

   QueryInterface : function (id)
   {
       if (id.equals(Components.interfaces["nsIObserver"]) ||
           id.equals(Components.interfaces["nsISupports"]))
       {
           return this;
       }
       throw Components.results.NS_NOINTERFACE;
   }
};

var obs = new Service("observer-service", "ObserverService");
obs.addObserver(myObserver, "http-on-modify-request", false);

Basically, on http-on-modify-request, I know how to examine the URI, figure out which window (if any) it's associated with, and a bunch of other stuff. What I can't figure out is how to redirect a request, which I know is possible from here, because I can get an nsIHttpChannel before any request is ever sent out.

Anyone know what to do? :/ I've been trying for a couple of weeks on and off, and got nowhere.

httprequest firefox-addon javascript
4 Answers

I've done it this way: stop nsIHttpChannel on "http-on-modify-request" event, get browser object for current window, call browser.loadURI.

var utils = require("sdk/window/utils");

function needsRedirect(url) {
    // to be implemented
    return true;
}

function generateNewUrl(url) {
    // to be implemented
    return "http://www.example.com/";
}

Cc["@mozilla.org/observer-service;1"]
    .getService(Ci.nsIObserverService)
    .addObserver({
        observe: function(subject, topic, data) {
            var channel = subject.QueryInterface(Ci.nsIHttpChannel);
            var url = channel.originalURI.spec;
            if (needsRedirect(url)) {
                //stop
                channel.cancel(Cr.NS_BINDING_ABORTED);

                //redirect
                var gBrowser = utils.getMostRecentBrowserWindow().gBrowser;
                var domWin = channel.notificationCallbacks.getInterface(Ci.nsIDOMWindow);
                var browser = gBrowser.getBrowserForDocument(domWin.top.document);
                browser.loadURI(generateNewUrl(url));

            }
        }
    }, "http-on-modify-request", false);
user_22291040
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