识别XHR（AJAX）的反应，一边听HTTP响应在Firefox插件插件、边听、反应、AJAX
我有一个简单的Firefox插件（插件-SDK）监听到http resposes和盖帽，如果响应的内容类型匹配一组内容类型。现在，观察者监听所有的答复时，我没有兴趣听的图像，JavaScript文件和AJAX（XHR）的反应。我能以某种方式过滤掉或至少找出应对属于一个XHR请求，这样我就不会浪费在处理响应的资源。
类似的事情，可以实现在Chrome浏览器扩展，其中details.type可以main_frame，图像，XHR等。
HTT presponseObserver =
{
注意：功能（主题，主题数据）
{
如果（主题==HTTP上审视反应）
{
VAR渠道= subject.QueryInterface（Ci.nsIHttpChannel）;
VAR的contentType;
尝试 {
的contentType = channel.getResponseHeader（Content-Type的'）;
如果（/\b(?:xml|rss|javascript|vnd|json|html|text|image|ocsp|x-shockwave-flash)\b/.test(contentType））
{
返回;
}
}
赶上（错误）{
返回;
}
}
}
解决方案
要求从 nsIXMLHtt prequest 接口 notificationCallbacks
VAR isXHR;
尝试{
VAR渠道= subject.QueryInterface（Ci.nsIHttpChannel）;
VAR回调= channel.notificationCallbacks;
VAR XHR =回调？ callbacks.getInterface（Ci.nsIXMLHtt prequest）：空;
isXHR = !! XHR;
}
赶上（E）{
isXHR = FALSE;
}
I have a simple firefox addon (addon-sdk) which listens to http resposes and blocks if content type of response matches a set of content types. Now, the observer listens to all the responses when I am not interested in listening to image, javascript files and ajax (XHR) responses. Can I somehow filter out or atleast find out that response belongs to an XHR request so that I don't waste resources on processing the response.
The similar thing can be achieved in chrome extensions where "details.type" can be main_frame, image, xhr etc.
httpResponseObserver =
{
observe: function(subject, topic, data)
{
if (topic == "http-on-examine-response")
{
var channel = subject.QueryInterface(Ci.nsIHttpChannel);
var contentType;
try {
contentType = channel.getResponseHeader('Content-Type');
if (/\b(?:xml|rss|javascript|vnd|json|html|text|image|ocsp|x-shockwave-flash)\b/.test(contentType))
{
return;
}
}
catch(error) {
return;
}
}
}
解决方案
Request the nsIXMLHttpRequest interface from notificationCallbacks
var isXHR;
try{
var channel = subject.QueryInterface(Ci.nsIHttpChannel);
var callbacks = channel.notificationCallbacks;
var xhr = callbacks ? callbacks.getInterface(Ci.nsIXMLHttpRequest) : null;
isXHR = !!xhr;
}
catch(e){
isXHR = false;
}
