ajax hook
目前為
此腳本不應該直接安裝，它是一個供其他腳本使用的函式庫。欲使用本函式庫，請在腳本 metadata 寫上： // @require https://update.cn-greasyfork.org/scripts/455943/1186873/ajaxHooker.js
// ==UserScript==
// @name ajaxHooker
// @author cxxjackie
// @version 1.2.4
// @supportURL https://bbs.tampermonkey.net.cn/thread-3284-1-1.html
// ==/UserScript==
var ajaxHooker = function() {
const win = window.unsafeWindow || document.defaultView || window;
const hookFns = [];
const realXhr = win.XMLHttpRequest;
const resProto = win.Response.prototype;
const toString = Object.prototype.toString;
const realFetch = win.fetch;
const xhrResponses = ['response', 'responseText', 'responseXML'];
const fetchResponses = ['arrayBuffer', 'blob', 'formData', 'json', 'text'];
const xhrAsyncEvents = ['readystatechange', 'load', 'loadend'];
let filter;
function emptyFn() {}
function errorFn(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 toFilterObj(obj) {
return {
type: obj.type,
url: obj.url,
method: obj.method && obj.method.toUpperCase()
};
}
function shouldFilter(type, url, method) {
return filter && !filter.find(obj =>
(!obj.type || obj.type === type)
&& (!obj.url || (toString.call(obj.url) === '[object String]' ? url.includes(obj.url) : obj.url.test(url)))
&& (!obj.method || obj.method === method.toUpperCase())
);
}
function lookupGetter(obj, prop) {
let getter;
let proto = obj;
while (proto) {
const descriptor = Object.getOwnPropertyDescriptor(proto, prop);
getter = descriptor && descriptor.get;
if (getter) break;
proto = Object.getPrototypeOf(proto);
}
return getter ? getter.bind(obj) : emptyFn;
}
function waitForHookFns(request) {
return Promise.all(hookFns.map(fn => Promise.resolve(fn(request)).then(emptyFn, errorFn)));
}
function waitForRequestKeys(request, requestClone) {
return Promise.all(['url', 'method', 'abort', 'headers', 'data'].map(key => {
return Promise.resolve(request[key]).then(val => request[key] = val, () => request[key] = requestClone[key]);
}));
}
function fakeEventSIP() {
this.ajaxHooker_stopped = true;
}
function xhrDelegateEvent(e) {
const xhr = e.target;
e.stopImmediatePropagation = fakeEventSIP;
xhr.__ajaxHooker.hookedEvents[e.type].forEach(fn => !e.ajaxHooker_stopped && fn.call(xhr, e));
const onEvent = xhr.__ajaxHooker.hookedEvents['on' + e.type];
typeof onEvent === 'function' && onEvent.call(xhr, e);
}
function xhrReadyStateChange(e) {
if (e.target.readyState === 4) {
e.target.dispatchEvent(new CustomEvent('ajaxHooker_responseReady', {detail: e}));
} else {
e.target.__ajaxHooker.delegateEvent(e);
}
}
function xhrLoadAndLoadend(e) {
e.target.__ajaxHooker.delegateEvent(e);
}
function fakeXhrOpen(method, url, ...args) {
const ah = this.__ajaxHooker;
ah.url = url.toString();
ah.method = method.toUpperCase();
ah.openArgs = args;
ah.headers = {};
return ah.originalMethods.open(method, url, ...args);
}
function fakeXhr() {
const xhr = new realXhr();
let ah = xhr.__ajaxHooker;
if (!ah) {
ah = xhr.__ajaxHooker = {
headers: {},
hookedEvents: {
readystatechange: new Set(),
load: new Set(),
loadend: new Set()
},
delegateEvent: xhrDelegateEvent,
originalGetters: {},
originalMethods: {}
};
xhr.addEventListener('readystatechange', xhrReadyStateChange);
xhr.addEventListener('load', xhrLoadAndLoadend);
xhr.addEventListener('loadend', xhrLoadAndLoadend);
for (const key of xhrResponses) {
ah.originalGetters[key] = lookupGetter(xhr, key);
}
for (const method of ['open', 'setRequestHeader', 'addEventListener', 'removeEventListener']) {
ah.originalMethods[method] = xhr[method].bind(xhr);
}
xhr.open = fakeXhrOpen;
xhr.setRequestHeader = (header, value) => {
ah.originalMethods.setRequestHeader(header, value);
if (xhr.readyState === 1) {
if (ah.headers[header]) {
ah.headers[header] += ', ' + value;
} else {
ah.headers[header] = value;
}
}
}
xhr.addEventListener = function(...args) {
if (xhrAsyncEvents.includes(args[0])) {
ah.hookedEvents[args[0]].add(args[1]);
} else {
ah.originalMethods.addEventListener(...args);
}
};
xhr.removeEventListener = function(...args) {
if (xhrAsyncEvents.includes(args[0])) {
ah.hookedEvents[args[0]].delete(args[1]);
} else {
ah.originalMethods.removeEventListener(...args);
}
};
xhrAsyncEvents.forEach(evt => {
const onEvt = 'on' + evt;
defineProp(xhr, onEvt, () => {
return ah.hookedEvents[onEvt] || null;
}, val => {
ah.hookedEvents[onEvt] = typeof val === 'function' ? val : null;
});
});
}
const realSend = xhr.send.bind(xhr);
xhr.send = function(data) {
if (xhr.readyState !== 1) return realSend(data);
ah.delegateEvent = xhrDelegateEvent;
xhrResponses.forEach(prop => {
delete xhr[prop]; // delete descriptor
});
if (shouldFilter('xhr', ah.url, ah.method)) {
xhr.addEventListener('ajaxHooker_responseReady', e => {
ah.delegateEvent(e.detail);
});
return realSend(data);
}
try {
const request = {
type: 'xhr',
url: ah.url,
method: ah.method,
abort: false,
headers: ah.headers,
data: data,
response: null
};
const requestClone = {...request};
waitForHookFns(request).then(() => {
waitForRequestKeys(request, requestClone).then(() => {
if (request.abort) return;
ah.originalMethods.open(request.method, request.url, ...ah.openArgs);
for (const header in request.headers) {
ah.originalMethods.setRequestHeader(header, request.headers[header]);
}
data = request.data;
xhr.addEventListener('ajaxHooker_responseReady', e => {
try {
if (typeof request.response === 'function') {
const arg = {
finalUrl: xhr.responseURL,
status: xhr.status,
responseHeaders: {}
};
for (const line of xhr.getAllResponseHeaders().trim().split(/[\r\n]+/)) {
const parts = line.split(/:\s*/);
if (parts.length === 2) {
const lheader = parts[0].toLowerCase();
if (arg.responseHeaders[lheader]) {
arg.responseHeaders[lheader] += ', ' + parts[1];
} else {
arg.responseHeaders[lheader] = parts[1];
}
}
}
xhrResponses.forEach(prop => {
defineProp(arg, prop, () => {
return arg[prop] = ah.originalGetters[prop]();
}, val => {
delete arg[prop];
arg[prop] = val;
});
defineProp(xhr, prop, () => {
const val = ah.originalGetters[prop]();
xhr.dispatchEvent(new CustomEvent('ajaxHooker_readResponse', {
detail: {prop, val}
}));
return val;
});
});
xhr.addEventListener('ajaxHooker_readResponse', e => {
arg[e.detail.prop] = e.detail.val;
});
const resPromise = Promise.resolve(request.response(arg)).then(() => {
const task = [];
xhrResponses.forEach(prop => {
const descriptor = Object.getOwnPropertyDescriptor(arg, prop);
if (descriptor && 'value' in descriptor) {
task.push(Promise.resolve(descriptor.value).then(val => {
arg[prop] = val;
defineProp(xhr, prop, () => {
xhr.dispatchEvent(new CustomEvent('ajaxHooker_readResponse', {
detail: {prop, val}
}));
return val;
});
}, emptyFn));
}
});
return Promise.all(task);
}, errorFn);
const eventsClone = {};
xhrAsyncEvents.forEach(type => {
eventsClone[type] = new Set([...ah.hookedEvents[type]]);
eventsClone['on' + type] = ah.hookedEvents['on' + type];
});
ah.delegateEvent = event => resPromise.then(() => {
event.stopImmediatePropagation = fakeEventSIP;
eventsClone[event.type].forEach(fn => !event.ajaxHooker_stopped && fn.call(xhr, event));
const onEvent = eventsClone['on' + event.type];
typeof onEvent === 'function' && onEvent.call(xhr, event);
});
}
} catch (err) {
console.error(err);
}
ah.delegateEvent(e.detail);
});
realSend(data);
});
});
} catch (err) {
console.error(err);
realSend(data);
}
};
return xhr;
}
function hookFetchResponse(response, arg, callback) {
fetchResponses.forEach(prop => {
response[prop] = () => new Promise((resolve, reject) => {
resProto[prop].call(response).then(res => {
if (prop in arg) {
resolve(arg[prop]);
} else {
try{
arg[prop] = res;
Promise.resolve(callback(arg)).then(() => {
if (prop in arg) {
Promise.resolve(arg[prop]).then(val => resolve(arg[prop] = val), () => resolve(res));
} else {
resolve(res);
}
}, errorFn);
} catch (err) {
console.error(err);
resolve(res);
}
}
}, reject);
});
});
}
function fakeFetch(url, init) {
if (url && typeof url.toString === 'function') {
url = url.toString();
init = init || {};
init.method = init.method || 'GET';
init.headers = init.headers || {};
if (shouldFilter('fetch', url, init.method)) return realFetch.call(win, url, init);
const request = {
type: 'fetch',
url: url,
method: init.method.toUpperCase(),
abort: false,
headers: {},
data: init.body,
response: null
};
if (toString.call(init.headers) === '[object Headers]') {
for (const [key, val] of init.headers) {
request.headers[key] = val;
}
} else {
request.headers = {...init.headers};
}
const requestClone = {...request};
return new Promise((resolve, reject) => {
try {
waitForHookFns(request).then(() => {
waitForRequestKeys(request, requestClone).then(() => {
if (request.abort) return reject('aborted');
url = request.url;
init.method = request.method;
init.headers = request.headers;
init.body = request.data;
realFetch.call(win, url, init).then(response => {
if (typeof request.response === 'function') {
const arg = {
finalUrl: response.url,
status: response.status,
responseHeaders: {}
};
for (const [key, val] of response.headers) {
arg.responseHeaders[key] = val;
}
hookFetchResponse(response, arg, request.response);
response.clone = () => {
const resClone = resProto.clone.call(response);
hookFetchResponse(resClone, arg, request.response);
return resClone;
};
}
resolve(response);
}, reject);
});
});
} catch (err) {
console.error(err);
return realFetch.call(win, url, init);
}
});
} else {
return realFetch.call(win, url, init);
}
}
win.XMLHttpRequest = fakeXhr;
Object.keys(realXhr).forEach(key => fakeXhr[key] = realXhr[key]);
fakeXhr.prototype = realXhr.prototype;
win.fetch = fakeFetch;
return {
hook: fn => hookFns.push(fn),
filter: arr => {
filter = Array.isArray(arr) && arr.map(toFilterObj)
},
protect: () => {
readonly(win, 'XMLHttpRequest', fakeXhr);
readonly(win, 'fetch', fakeFetch);
},
unhook: () => {
writable(win, 'XMLHttpRequest', realXhr);
writable(win, 'fetch', realFetch);
}
};
}();