provide.js

/**
 * Copyright 2016 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


import {DEV_ID} from './constants';
import {capitalize} from './utilities';


/**
 * Provides a plugin for use with analytics.js, accounting for the possibility
 * that the global command queue has been renamed or not yet defined.
 * @param {string} pluginName The plugin name identifier.
 * @param {Function} pluginConstructor The plugin constructor function.
 */
export default function provide(pluginName, pluginConstructor) {
  const gaAlias = window.GoogleAnalyticsObject || 'ga';
  window[gaAlias] = window[gaAlias] || function(...args) {
    (window[gaAlias].q = window[gaAlias].q || []).push(args);
  };

  // Adds the autotrack dev ID if not already included.
  window.gaDevIds = window.gaDevIds || [];
  if (window.gaDevIds.indexOf(DEV_ID) < 0) {
    window.gaDevIds.push(DEV_ID);
  }

  // Formally provides the plugin for use with analytics.js.
  window[gaAlias]('provide', pluginName, pluginConstructor);

  // Registers the plugin on the global gaplugins object.
  window.gaplugins = window.gaplugins || {};
  window.gaplugins[capitalize(pluginName)] = pluginConstructor;
}