ajax劫持库，支持xhr和fetch劫持。
此脚本不应直接安装，它是一个供其他脚本使用的外部库。如果您需要使用该库，请在脚本元属性加入：// @require https://update.greasyfork.org/scripts/483208/1377351/ajaxHooker_myaijarvis.js
// ==UserScript==
// @name ajaxHooker_myaijarvis
// @description ajax劫持库，支持xhr和fetch劫持。
// @author cxxjackie
// @version 1.4.1
// @supportURL https://bbs.tampermonkey.net.cn/thread-3284-1-1.html
// ==/UserScript==
var ajaxHooker = function() {
'use strict';
const version = '1.4.1';
const hookInst = {
hookFns: [],
filters: []
};
const win = window.unsafeWindow || document.defaultView || window;
let winAh = win.__ajaxHooker;
const resProto = win.Response.prototype;
const xhrResponses = ['response', 'responseText', 'responseXML'];
const fetchResponses = ['arrayBuffer', 'blob', 'formData', 'json', 'text'];
const fetchInitProps = ['method', 'headers', 'body', 'mode', 'credentials', 'cache', 'redirect',
'referrer', 'referrerPolicy', 'integrity', 'keepalive', 'signal', 'priority'];
const xhrAsyncEvents = ['readystatechange', 'load', 'loadend'];
const getType = ({}).toString.call.bind(({}).toString);
const getDescriptor = Object.getOwnPropertyDescriptor.bind(Object);
const emptyFn = () => {};
const errorFn = e => console.error(e);
function isThenable(obj) {
return obj && ['object', 'function'].includes(typeof obj) && typeof obj.then === 'function';
}
function catchError(fn, ...args) {
try {
const result = fn(...args);
if (isThenable(result)) return result.then(null, errorFn);
return result;
} catch (err) {
console.error(err);
}
}
function defineProp(obj, prop, getter, setter) {
Object.defineProperty(obj, prop, {
configurable: true,
enumerable: true,
get: getter,
set: setter
});
}
function readonly(obj, prop, value = obj[prop]) {
defineProp(obj, prop, () => value, emptyFn);
}
function writable(obj, prop, value = obj[prop]) {
Object.defineProperty(obj, prop, {
configurable: true,
enumerable: true,
writable: true,
value: value
});
}
function parseHeaders(obj) {
const headers = {};
switch (getType(obj)) {
case '[object String]':
for (const line of obj.trim().split(/[\r\n]+/)) {
const [header, value] = line.split(/\s*:\s*/);
if (!header) break;
const lheader = header.toLowerCase();
headers[lheader] = lheader in headers ? `${headers[lheader]}, ${value}` : value;
}
break;
case '[object Headers]':
for (const [key, val] of obj) {
headers[key] = val;
}
break;
case '[object Object]':
return {...obj};
}
return headers;
}
function stopImmediatePropagation() {
this.ajaxHooker_isStopped = true;
}
class SyncThenable {
then(fn) {
fn && fn();
return new SyncThenable();
}
}
class AHRequest {
constructor(request) {
this.request = request;
this.requestClone = {...this.request};
}
shouldFilter(filters) {
const {type, url, method, async} = this.request;
return filters.length && !filters.find(obj => {
switch (true) {
case obj.type && obj.type !== type:
case getType(obj.url) === '[object String]' && !url.includes(obj.url):
case getType(obj.url) === '[object RegExp]' && !obj.url.test(url):
case obj.method && obj.method.toUpperCase() !== method.toUpperCase():
case 'async' in obj && obj.async !== async:
return false;
}
return true;
});
}
waitForRequestKeys() {
const requestKeys = ['url', 'method', 'abort', 'headers', 'data'];
if (!this.request.async) {
win.__ajaxHooker.hookInsts.forEach(({hookFns, filters}) => {
if (this.shouldFilter(filters)) return;
hookFns.forEach(fn => {
if (getType(fn) === '[object Function]') catchError(fn, this.request);
});
requestKeys.forEach(key => {
if (isThenable(this.request[key])) this.request[key] = this.requestClone[key];
});
});
return new SyncThenable();
}
const promises = [];
win.__ajaxHooker.hookInsts.forEach(({hookFns, filters}) => {
if (this.shouldFilter(filters)) return;
promises.push(Promise.all(hookFns.map(fn => catchError(fn, this.request))).then(() =>
Promise.all(requestKeys.map(key => Promise.resolve(this.request[key]).then(
val => this.request[key] = val,
() => this.request[key] = this.requestClone[key]
)))
));
});
return Promise.all(promises);
}
waitForResponseKeys(response) {
const responseKeys = this.request.type === 'xhr' ? xhrResponses : fetchResponses;
if (!this.request.async) {
if (getType(this.request.response) === '[object Function]') {
catchError(this.request.response, response);
responseKeys.forEach(key => {
if ('get' in getDescriptor(response, key) || isThenable(response[key])) {
delete response[key];
}
});
}
return new SyncThenable();
}
return Promise.resolve(catchError(this.request.response, response)).then(() =>
Promise.all(responseKeys.map(key => {
const descriptor = getDescriptor(response, key);
if (descriptor && 'value' in descriptor) {
return Promise.resolve(descriptor.value).then(
val => response[key] = val,
() => delete response[key]
);
} else {
delete response[key];
}
}))
);
}
}
const proxyHandler = {
get(target, prop) {
const descriptor = getDescriptor(target, prop);
if (descriptor && !descriptor.configurable && !descriptor.writable && !descriptor.get) return target[prop];
const ah = target.__ajaxHooker;
if (ah && ah.proxyProps) {
if (prop in ah.proxyProps) {
const pDescriptor = ah.proxyProps[prop];
if ('get' in pDescriptor) return pDescriptor.get();
if (typeof pDescriptor.value === 'function') return pDescriptor.value.bind(ah);
return pDescriptor.value;
}
if (typeof target[prop] === 'function') return target[prop].bind(target);
}
return target[prop];
},
set(target, prop, value) {
const descriptor = getDescriptor(target, prop);
if (descriptor && !descriptor.configurable && !descriptor.writable && !descriptor.set) return true;
const ah = target.__ajaxHooker;
if (ah && ah.proxyProps && prop in ah.proxyProps) {
const pDescriptor = ah.proxyProps[prop];
pDescriptor.set ? pDescriptor.set(value) : (pDescriptor.value = value);
} else {
target[prop] = value;
}
return true;
}
};
class XhrHooker {
constructor(xhr) {
const ah = this;
Object.assign(ah, {
originalXhr: xhr,
proxyXhr: new Proxy(xhr, proxyHandler),
resThenable: new SyncThenable(),
proxyProps: {},
proxyEvents: {}
});
xhr.addEventListener('readystatechange', e => {
if (ah.proxyXhr.readyState === 4 && ah.request && typeof ah.request.response === 'function') {
const response = {
finalUrl: ah.proxyXhr.responseURL,
status: ah.proxyXhr.status,
responseHeaders: parseHeaders(ah.proxyXhr.getAllResponseHeaders())
};
const tempValues = {};
for (const key of xhrResponses) {
try {
tempValues[key] = ah.originalXhr[key];
} catch (err) {}
defineProp(response, key, () => {
return response[key] = tempValues[key];
}, val => {
delete response[key];
response[key] = val;
});
}
ah.resThenable = new AHRequest(ah.request).waitForResponseKeys(response).then(() => {
for (const key of xhrResponses) {
ah.proxyProps[key] = {get: () => {
if (!(key in response)) response[key] = tempValues[key];
return response[key];
}};
}
});
}
ah.dispatchEvent(e);
});
xhr.addEventListener('load', e => ah.dispatchEvent(e));
xhr.addEventListener('loadend', e => ah.dispatchEvent(e));
for (const evt of xhrAsyncEvents) {
const onEvt = 'on' + evt;
ah.proxyProps[onEvt] = {
get: () => ah.proxyEvents[onEvt] || null,
set: val => ah.addEvent(onEvt, val)
};
}
for (const method of ['setRequestHeader', 'addEventListener', 'removeEventListener', 'open', 'send']) {
ah.proxyProps[method] = {value: ah[method]};
}
}
toJSON() {} // Converting circular structure to JSON
addEvent(type, event) {
if (type.startsWith('on')) {
this.proxyEvents[type] = typeof event === 'function' ? event : null;
} else {
if (typeof event === 'object' && event !== null) event = event.handleEvent;
if (typeof event !== 'function') return;
this.proxyEvents[type] = this.proxyEvents[type] || new Set();
this.proxyEvents[type].add(event);
}
}
removeEvent(type, event) {
if (type.startsWith('on')) {
this.proxyEvents[type] = null;
} else {
if (typeof event === 'object' && event !== null) event = event.handleEvent;
this.proxyEvents[type] && this.proxyEvents[type].delete(event);
}
}
dispatchEvent(e) {
e.stopImmediatePropagation = stopImmediatePropagation;
defineProp(e, 'target', () => this.proxyXhr);
this.proxyEvents[e.type] && this.proxyEvents[e.type].forEach(fn => {
this.resThenable.then(() => !e.ajaxHooker_isStopped && fn.call(this.proxyXhr, e));
});
if (e.ajaxHooker_isStopped) return;
const onEvent = this.proxyEvents['on' + e.type];
onEvent && this.resThenable.then(onEvent.bind(this.proxyXhr, e));
}
setRequestHeader(header, value) {
this.originalXhr.setRequestHeader(header, value);
if (this.originalXhr.readyState !== 1) return;
const headers = this.request.headers;
headers[header] = header in headers ? `${headers[header]}, ${value}` : value;
}
addEventListener(...args) {
if (xhrAsyncEvents.includes(args[0])) {
this.addEvent(args[0], args[1]);
} else {
this.originalXhr.addEventListener(...args);
}
}
removeEventListener(...args) {
if (xhrAsyncEvents.includes(args[0])) {
this.removeEvent(args[0], args[1]);
} else {
this.originalXhr.removeEventListener(...args);
}
}
open(method, url, async = true, ...args) {
this.request = {
type: 'xhr',
url: url.toString(),
method: method.toUpperCase(),
abort: false,
headers: {},
data: null,
response: null,
async: !!async
};
this.openArgs = args;
this.resThenable = new SyncThenable();
['responseURL', 'readyState', 'status', 'statusText', ...xhrResponses].forEach(key => {
delete this.proxyProps[key];
});
return this.originalXhr.open(method, url, async, ...args);
}
send(data) {
const ah = this;
const xhr = ah.originalXhr;
const request = ah.request;
if (!request) return xhr.send(data);
request.data = data;
new AHRequest(request).waitForRequestKeys().then(() => {
if (request.abort) {
if (typeof request.response === 'function') {
Object.assign(ah.proxyProps, {
responseURL: {value: request.url},
readyState: {value: 4},
status: {value: 200},
statusText: {value: 'OK'}
});
xhrAsyncEvents.forEach(evt => xhr.dispatchEvent(new Event(evt)));
}
} else {
xhr.open(request.method, request.url, request.async, ...ah.openArgs);
for (const header in request.headers) {
xhr.setRequestHeader(header, request.headers[header]);
}
xhr.send(request.data);
}
});
}
}
function fakeXHR() {
const xhr = new winAh.realXHR();
if ('__ajaxHooker' in xhr) console.warn('检测到不同版本的ajaxHooker，可能发生冲突！');
xhr.__ajaxHooker = new XhrHooker(xhr);
return xhr.__ajaxHooker.proxyXhr;
}
fakeXHR.prototype = win.XMLHttpRequest.prototype;
Object.keys(win.XMLHttpRequest).forEach(key => fakeXHR[key] = win.XMLHttpRequest[key]);
function fakeFetch(url, options = {}) {
if (!url) return winAh.realFetch.call(win, url, options);
const init = {};
if (getType(url) === '[object Request]') {
for (const prop of fetchInitProps) init[prop] = url[prop];
url = url.url;
}
url = url.toString();
Object.assign(init, options);
init.method = init.method || 'GET';
init.headers = init.headers || {};
const request = {
type: 'fetch',
url: url,
method: init.method.toUpperCase(),
abort: false,
headers: parseHeaders(init.headers),
data: init.body,
response: null,
async: true
};
const req = new AHRequest(request);
return new Promise((resolve, reject) => {
req.waitForRequestKeys().then(() => {
if (request.abort) {
if (typeof request.response === 'function') {
const response = {
finalUrl: request.url,
status: 200,
responseHeaders: {}
};
req.waitForResponseKeys(response).then(() => {
const key = fetchResponses.find(k => k in response);
let val = response[key];
if (key === 'json' && typeof val === 'object') {
val = catchError(JSON.stringify.bind(JSON), val);
}
const res = new Response(val, {
status: 200,
statusText: 'OK'
});
defineProp(res, 'type', () => 'basic');
defineProp(res, 'url', () => request.url);
resolve(res);
});
} else {
reject(new DOMException('aborted', 'AbortError'));
}
return;
}
init.method = request.method;
init.headers = request.headers;
init.body = request.data;
winAh.realFetch.call(win, request.url, init).then(res => {
if (typeof request.response === 'function') {
const response = {
finalUrl: res.url,
status: res.status,
responseHeaders: parseHeaders(res.headers)
};
fetchResponses.forEach(key => res[key] = function() {
if (key in response) return Promise.resolve(response[key]);
return resProto[key].call(this).then(val => {
response[key] = val;
return req.waitForResponseKeys(response).then(() => key in response ? response[key] : val);
});
});
}
resolve(res);
}, reject);
}).catch(err => {
console.error(err);
resolve(winAh.realFetch.call(win, url, init));
});
});
}
function fakeFetchClone() {
const descriptors = Object.getOwnPropertyDescriptors(this);
const res = winAh.realFetchClone.call(this);
Object.defineProperties(res, descriptors);
return res;
}
winAh = win.__ajaxHooker = winAh || {
version, fakeXHR, fakeFetch, fakeFetchClone,
realXHR: win.XMLHttpRequest,
realFetch: win.fetch,
realFetchClone: resProto.clone,
hookInsts: new Set()
};
if (winAh.version !== version) console.warn('检测到不同版本的ajaxHooker，可能发生冲突！');
win.XMLHttpRequest = winAh.fakeXHR;
win.fetch = winAh.fakeFetch;
resProto.clone = winAh.fakeFetchClone;
winAh.hookInsts.add(hookInst);
return {
hook: fn => hookInst.hookFns.push(fn),
filter: arr => {
if (Array.isArray(arr)) hookInst.filters = arr;
},
protect: () => {
readonly(win, 'XMLHttpRequest', winAh.fakeXHR);
readonly(win, 'fetch', winAh.fakeFetch);
readonly(resProto, 'clone', winAh.fakeFetchClone);
},
unhook: () => {
winAh.hookInsts.delete(hookInst);
if (!winAh.hookInsts.size) {
writable(win, 'XMLHttpRequest', winAh.realXHR);
writable(win, 'fetch', winAh.realFetch);
writable(resProto, 'clone', winAh.realFetchClone);
delete win.__ajaxHooker;
}
}
};
}();