Question

I need to extend firebug to use the link extracted from the webpage(when a download from any link in the page is initiated) to send it to another machine where it will be downloaded. I was planning to use firebug to extract this link for me. If there is any other way I can get this information from the browser, even that would be appreciated.

Answer 1

actually, its bad idea to use events to detect things like http requests,the power of firefox xul language gives you the ability to detect the all browsers requests/response then you can decide what links you need from the request/response header:

you can use “http-observe” witch actually Firebug use for the net panel

– here is the link for “http-observe” in mozilla MDN [https://developer.mozilla.org/en/Setting_HTTP_request_headers][1]

– also here is a simple example for “http-observe”

// first create observerService component as a property into your extension javascript object
    var myExtension = {   observerService:Components.classes["@mozilla.org/observerservice;1"].getService(Components.interfaces.nsIObserverService),
        init:function(){
            // in the init function setup the observe service and set witch javascript object is the listener for http response for example "this"
            this.observerService.addObserver(this,"http-on-examine-response", false);
            this.observerService.addObserver(this,"http-on-examine-cached-response", false);
        },
        observe: function(aSubject, aTopic, aData){ // the observe function
            if (aTopic == "http-on-examine-response" || aTopic == "http-on-examine-cached-response"){
                var httpChannel = aSubject.QueryInterface(Components.interfaces.nsIHttpChannel);
                var URI = httpChannel.originalURI.spec;                    
                if (aSubject.loadFlags & httpChannel.LOAD_INITIAL_DOCUMENT_URI){ // this detect if the response is primery request 
                    var contentType = httpChannel.getResponseHeader("content-type"); // check the heder content-type 
                    if (contentType == "what ever you want"){ // you can check if it zip/html/xml ...etc
                //do what ever you want
                }
                }
            }
        }   
    }