sententiaregum-flux-container/lib/connector.js

The flux implementation of the sententiaregum project based on facebook/flux

/*
 * This file is part of the Sententiaregum project.
 *
 * (c) Maximilian Bosch <maximilian.bosch.27@gmail.com>
 * (c) Ben Bieler <benjaminbieler2014@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _invariant = require('invariant');

var _invariant2 = _interopRequireDefault(_invariant);

var _events = require('events');

var _events2 = _interopRequireDefault(_events);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var list = [];

/**
 * Connection API which creates view listeners that can react on a refreshed store.
 *
 * @param {Object} store The store which should be handled by the view.
 *
 * @returns {{subscribe:Function,unsubscribe:Function,register:Function}} The internal connection API.
 */

exports.default = function (store) {
  /**
   * Manual modification of the emitter.
   * This function handles how the emitter is managed in the connection API.
   *
   * @param {Function} handler The handler to be called in case of flushing changes.
   * @param {String}   type    The type (e.g. addListener/removeListener).
   *
   * @returns {void}
   */
  function modifyEmitter(handler, type) {
    (0, _invariant2.default)(isStoreKnown(store), 'The store is not registered! Please use the `store()` function to assemble a store properly and register it automatically!');
    (0, _invariant2.default)(typeof handler === 'function', 'The store handler must be a function!');

    getEmitter(store)[type]('change', handler);
  }

  /**
   * Checks whether the list is aware of the store passed as argument.
   *
   * @param {Object} store The store to check.
   *
   * @returns {boolean}
   */
  function isStoreKnown(store) {
    return list.length > 0 && list.some(function (item) {
      return item[0] === store;
    });
  }

  /**
   * Checks for the emitter.
   *
   * @param {Object} store The store associated to the emitter.
   *
   * @returns {EventEmitter}
   */
  function getEmitter(store) {
    return list.find(function (item) {
      return item[0] === store ? item : false;
    })[1];
  }

  return new (function () {
    function _class() {
      _classCallCheck(this, _class);
    }

    _createClass(_class, [{
      key: 'subscribe',

      /**
       * Associates the handler with the given store.
       *
       * @param {Function} handler The handler to check.
       *
       * @returns {void}
       */
      value: function subscribe(handler) {
        modifyEmitter(handler, 'addListener');
      }

      /**
       * Unsubscribes the handler with the given store.
       *
       * @param {Function} handler The handler to check.
       *
       * @returns {void}
       */

    }, {
      key: 'unsubscribe',
      value: function unsubscribe(handler) {
        modifyEmitter(handler, 'removeListener');
      }

      /**
       * API for the registration of the store.
       *
       * @param {EventEmitter} emitter Emitter.
       *
       * @returns {void}
       */

    }, {
      key: 'register',
      value: function register(emitter) {
        (0, _invariant2.default)(emitter instanceof _events2.default, 'Emitter must be node\'s core emitter!');

        if (!isStoreKnown(store)) {
          list.push([store, emitter]);
        }
      }
    }]);

    return _class;
  }())();
};