1// Copyright 2014 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5/** 6 * @fileoverview Implements a "generic" RequestHelper that provides a default 7 * response to unknown requests, and supports registering handlers for known 8 * requests. 9 */ 10'use strict'; 11 12/** 13 * @typedef {function(HelperRequest): RequestHandler} */ 14var RequestHandlerFactory; 15 16/** 17 * Implements a "generic" RequestHelper that provides a default 18 * response to unknown requests, and supports registering handlers for known 19 * @constructor 20 * @implements {RequestHelper} 21 */ 22function GenericRequestHelper() { 23 /** @private {Object.<string, RequestHandlerFactory>} */ 24 this.handlerFactories_ = {}; 25} 26 27/** 28 * Gets a handler for a request. 29 * @param {HelperRequest} request The request to handle. 30 * @return {RequestHandler} A handler for the request. 31 */ 32GenericRequestHelper.prototype.getHandler = function(request) { 33 if (this.handlerFactories_.hasOwnProperty(request.type)) { 34 return this.handlerFactories_[request.type](request); 35 } 36 return null; 37}; 38 39/** 40 * Registers a handler factory for a given type. 41 * @param {string} type The request type. 42 * @param {RequestHandlerFactory} factory A factory that can produce a handler 43 * for a request of a given type. 44 */ 45GenericRequestHelper.prototype.registerHandlerFactory = 46 function(type, factory) { 47 this.handlerFactories_[type] = factory; 48}; 49