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function interceptNetworkRequests(ee) {
const open = XMLHttpRequest.prototype.open;
const send = XMLHttpRequest.prototype.send;
const isRegularXHR = open.toString().indexOf('native code') !== -1;
// don't hijack if already hijacked - this will mess up with frameworks like Angular with zones
// we work if we load first there which we can.
if (isRegularXHR) {
XMLHttpRequest.prototype.open = function() {
ee.onOpen && ee.onOpen(this, arguments);
if (ee.onLoad) {
this.addEventListener('load', ee.onLoad.bind(ee));
}
if (ee.onError) {
this.addEventListener('error', ee.onError.bind(ee));
}
return open.apply(this, arguments);
};
XMLHttpRequest.prototype.send = function() {
ee.onSend && ee.onSend(this, arguments);
return send.apply(this, arguments);
};
}
const fetch = window.fetch || "";
// don't hijack twice, if fetch is built with XHR no need to decorate, if already hijacked
// then this is dangerous and we opt out
const isFetchNative = fetch.toString().indexOf('native code') !== -1;
if(isFetchNative) {
window.fetch = function () {
ee.onFetch && ee.onFetch(arguments);
const p = fetch.apply(this, arguments);
p.then(ee.onFetchResponse, ee.onFetchError);
return p;
};
// at the moment, we don't listen to streams which are likely video
const json = Response.prototype.json;
const text = Response.prototype.text;
const blob = Response.prototype.blob;
Response.prototype.json = function () {
const p = json.apply(this.arguments);
p.then(ee.onFetchLoad && ee.onFetchLoad.bind(ee, "json"));
return p;
};
Response.prototype.text = function () {
const p = text.apply(this.arguments);
p.then(ee.onFetchLoad && ee.onFetchLoad.bind(ee, "text"));
return p;
};
Response.prototype.blob = function () {
const p = blob.apply(this.arguments);
p.then(ee.onFetchLoad && ee.onFetchLoad.bind(ee, "blob"));
return p;
};
}
return ee;
}
interceptNetworkRequests({
onFetch: console.log,
onFetchResponse: console.log,
onFetchLoad: console.log,
onOpen: console.log,
onSend: console.log,
onError: console.log,
onLoad: console.log
});
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