在Firefox扩展中改变HTTP响应
如何在Firefox扩展中更改HTTP响应正文？ 我使用下面的代码设置了一个http-on-examine-response观察者和一个nsIStreamListener对象。 获取数据，解析并修改数据后，如何将更改的响应返回给Firefox浏览器？ 例如，假设我在启用了我的扩展程序的情况下访问Google.com，扩展程序应拦截响应并将每次发生的“谷歌”更改为“护目镜”。 所以当页面加载时，用户会在任何地方看到“护目镜”。
function TmSteroidsObserver()
{
this.register();
}
TmSteroidsObserver.prototype = {
observe: function(subject, topic, data) {
if (topic == "http-on-examine-response") {
}
else if (topic == "http-on-modify-request") {
var channel = subject.QueryInterface(Components.interfaces.nsIChannel);
var listener = new StreamListener(channel);
}
},
register: function() {
var observerService = Components.classes["@mozilla.org/observer-service;1"]
.getService(Components.interfaces.nsIObserverService);
observerService.addObserver(listener, "http-on-modify-request", false);
observerService.addObserver(listener, "http-on-examine-response", false);
},
unregister: function() {
var observerService = Components.classes["@mozilla.org/observer-service;1"]
.getService(Components.interfaces.nsIObserverService);
observerService.removeObserver(this, "http-on-modify-request");
observerService.removeObserver(this, "http-on-examine-response");
},
QueryInterface : function(aIID) {
if (aIID.equals(Components.interfaces.nsISupports) ||
aIID.equals(Components.interfaces.nsIObserver))
return this;
throw Components.results.NS_NOINTERFACE;
}
}
function StreamListener(channel) {
channel.notificationCallbacks = listener;
channel.asyncOpen(listener, null);
}
StreamListener.prototype = {
mData: "",
mChannel: null,
// nsIStreamListener
onStartRequest: function (aRequest, aContext) {
this.mData = "";
},
onDataAvailable: function (aRequest, aContext, aStream, aSourceOffset, aLength) {
var scriptableInputStream =
Components.classes["@mozilla.org/scriptableinputstream;1"]
.createInstance(Components.interfaces.nsIScriptableInputStream);
scriptableInputStream.init(aStream);
this.mData += scriptableInputStream.read(aLength);
},
onStopRequest: function (aRequest, aContext, aStatus) {
if (Components.isSuccessCode(aStatus)) {
// request was successfull
this.mCallbackFunc(this.mData);
} else {
// request failed
this.mCallbackFunc(null);
}
this.mChannel = null;
},
// nsIChannelEventSink
onChannelRedirect: function (aOldChannel, aNewChannel, aFlags) {
// if redirecting, store the new channel
this.mChannel = aNewChannel;
},
// nsIInterfaceRequestor
getInterface: function (aIID) {
try {
return this.QueryInterface(aIID);
} catch (e) {
throw Components.results.NS_NOINTERFACE;
}
},
// nsIProgressEventSink (not implementing will cause annoying exceptions)
onProgress : function (aRequest, aContext, aProgress, aProgressMax) { },
onStatus : function (aRequest, aContext, aStatus, aStatusArg) { },
// nsIHttpEventSink (not implementing will cause annoying exceptions)
onRedirect : function (aOldChannel, aNewChannel) { },
// we are faking an XPCOM interface, so we need to implement QI
QueryInterface : function(aIID) {
if (aIID.equals(Components.interfaces.nsISupports) ||
aIID.equals(Components.interfaces.nsIInterfaceRequestor) ||
aIID.equals(Components.interfaces.nsIChannelEventSink) ||
aIID.equals(Components.interfaces.nsIProgressEventSink) ||
aIID.equals(Components.interfaces.nsIHttpEventSink) ||
aIID.equals(Components.interfaces.nsIStreamListener))
return this;
throw Components.results.NS_NOINTERFACE;
}
};
您可以使用nsITraceableChannel来拦截响应。
您应该修改所需的数据并将其传递给innerListener的OnDataAvailable
以下链接将帮助您更好地理解这一点。
http://www.softwareishard.com/blog/firebug/nsitraceablechannel-intercept-http-traffic/
http://www.ashita.org/howto-xhr-listening-by-a-firefox-addon/
观察员服务只是打电话给你的听众。 Firefox将收到请求，呼叫您的听众并发送回复。 请参阅Mozilla文档创建HTTP POST。
链接地址: http://www.djcxy.com/p/74023.html