XMLHttpRequestを仲介するユーザースクリプト (Tampermonkey)

xhr-intercept.js

// ==UserScript==
// @name         xhr-intercept
// @namespace    https://github.com/BiasHacker
// @version      0.1
// @description  XMLHttpRequestを仲介します。
// @author       Sin
// @match        https://hoge.com/*
// @grant        none
// @run-at document-start
// ==/UserScript==

(function() {
    'use strict';
    window.nativeXHR = {
        open: XMLHttpRequest.prototype.open,
        send: XMLHttpRequest.prototype.send
    };
    var parseQueryString = function(value) {
        return value.split('&').reduce(function(obj, text) {
          var keyValue = text.split('=');
          if (keyValue[0]) {
              obj[keyValue[0]] = decodeURIComponent(keyValue[1] || '');
          }
          return obj;
        }, {});
    }, encodeQueryString = function(value) {
        return Object.keys(value).map(function(key) {
            return key + '=' + encodeURIComponent(value[key]);
        }).join('&');
    };
    XMLHttpRequest.prototype.open = function() {
        this.argsOpen = arguments;
        window.nativeXHR.open.apply(this, arguments);
    };
    XMLHttpRequest.prototype.send = function(payload) {
        if (payload) console.log(this.argsOpen[1], parseQueryString(payload));
        window.nativeXHR.send.apply(this, arguments);
    };
})();