# init.js

    const AV = require('./av');
    const request = require('./request');

    const initialize = (appId, appKey, masterKey) => {
      if (AV.applicationId && appId !== AV.applicationId && appKey !== AV.applicationKey && masterKey !== AV.masterKey) {
        console.warn('LeanCloud SDK is already initialized, please do not reinitialize it.');
      }
      AV.applicationId = appId;
      AV.applicationKey = appKey;
      AV.masterKey = masterKey;
      AV._useMasterKey = false;
    };

    const masterKeyWarn = () => {
      console.warn('MasterKey is not supposed to be used in browser.');
    };

    /**
      * Call this method first to set up your authentication tokens for AV.
      * You can get your app keys from the LeanCloud dashboard on http://leancloud.cn .
      * @function AV.init
      * @param {Object} options
      * @param {String} options.appId application id
      * @param {String} options.appKey application key
      * @param {String} options.masterKey application master key
    */

    AV.init = (...args) => {
      switch (args.length) {
        case 1:
          const options = args[0];
          if (typeof options === 'object') {
            if (!AV._config.isNode && options.masterKey) {
              masterKeyWarn();
            }
            initialize(options.appId, options.appKey, options.masterKey);
            request.setServerUrlByRegion(options.region);
            AV._config.disableCurrentUser = options.disableCurrentUser;
          } else {
            throw new Error('AV.init(): Parameter is not correct.');
          }
        break;
        // 兼容旧版本的初始化方法
        case 2:
        case 3:
          console.warn('Please use AV.init() to replace AV.initialize(), ' +
           'AV.init() need an Object param, like { appId: \'YOUR_APP_ID\', appKey: \'YOUR_APP_KEY\' } . ' +
           'Docs: https://leancloud.cn/docs/sdk_setup-js.html');
          if (!AV._config.isNode && args.length === 3) {
            masterKeyWarn();
          }
          initialize(...args);
          request.setServerUrlByRegion('cn');
        break;
      }
    };

    // If we're running in node.js, allow using the master key.
    if (AV._config.isNode) {
      AV.Cloud = AV.Cloud || {};
      /**
       * Switches the LeanCloud SDK to using the Master key.  The Master key grants
       * priveleged access to the data in LeanCloud and can be used to bypass ACLs and
       * other restrictions that are applied to the client SDKs.
       * <p><strong><em>Available in Cloud Code and Node.js only.</em></strong>
       * </p>
       */
      AV.Cloud.useMasterKey = function() {
        AV._useMasterKey = true;
      };
    }

    // 兼容老版本的初始化方法
    AV.initialize = AV.init;