chronosjs
Version:
JS Channels Mechanism
781 lines (707 loc) • 42.4 kB
JavaScript
/**
* LIMITATIONS:
* 1) Only supports browsers which implements postMessage API and have native JSON implementation (IE8+, Chrome, FF, Safari, Opera, IOS, Opera Mini, Android)
* 2) IE9-, FF & Opera Mini does not support MessageChannel and therefore we fallback to using basic postMessage.
* This makes the communication opened to any handler registered for messages on the same origin.
* 3) All passDataByRef flags (in LPEventChannel) are obviously ignored
* 4) In case the browser does not support passing object using postMessage (IE8+, Opera Mini), and no special serialize/deserialize methods are supplied to PostMessageCourier,
* All data is serialized using JSON.stringify/JSON.parse which means that Object data is limited to JSON which supports types like:
* strings, numbers, null, arrays, and objects (and does not allow circular references).
* Trying to serialize other types, will result in conversion to null (like Infinity or NaN) or to a string (Dates)
* that must be manually deserialized on the other side
* 5) When Iframe is managed outside of PostMessageCourier (passed by reference to the constructor),
* a targetOrigin option is expected to be passed to the constructor, and a query parameter with the name "lpHost" is expected on the iframe url (unless the PostMessageCourier
* at the iframe side, had also been initialized with a valid targetOrigin option)
*/
// TODO: Add Support for target management when there is a problem that requires re-initialization of the target
;(function (root, cacherRoot, circuitRoot, factory) {
"use strict";
/* istanbul ignore if */
//<amd>
if ("function" === typeof define && define.amd) {
// AMD. Register as an anonymous module.
define("Chronos.PostMessageCourier", ["Chronos.PostMessageUtilities", "Chronos.Channels", "cacher", "CircuitBreaker", "Chronos.PostMessageChannel", "Chronos.PostMessagePromise", "Chronos.PostMessageMapper"],
function (PostMessageUtilities, Channels, cacher, CircuitBreaker, PostMessageChannel, PostMessagePromise, PostMessageMapper) {
return factory(root, root, PostMessageUtilities, Channels,
cacher, CircuitBreaker, PostMessageChannel, PostMessagePromise, PostMessageMapper, true);
});
return;
}
//</amd>
/* istanbul ignore next */
if ("object" !== typeof exports) {
/**
* @depend ../Channels.js
* @depend ../../node_modules/circuit-breakerjs/src/CircuitBreaker.js
* @depend ../../node_modules/cacherjs/src/cacher.js
* @depend ./PostMessageUtilities.js
* @depend ./PostMessageChannel.js
* @depend ./PostMessagePromise.js
* @depend ./PostMessageMapper.js
*/
root.Chronos = root.Chronos || {};
factory(root, root.Chronos, root.Chronos.PostMessageUtilities, root.Chronos.Channels,
cacherRoot.Cacher, circuitRoot.CircuitBreaker,
root.Chronos.PostMessageChannel, root.Chronos.PostMessagePromise, root.Chronos.PostMessageMapper);
}
}(typeof ChronosRoot === "undefined" ? this : ChronosRoot,
typeof CacherRoot === "undefined" ? this : CacherRoot,
typeof CircuitRoot === "undefined" ? this : CircuitRoot,
function (root, exports, PostMessageUtilities, Channels, Cacher, CircuitBreaker, PostMessageChannel, PostMessagePromise, PostMessageMapper, hide) {
"use strict";
/*jshint validthis:true */
var MESSAGE_PREFIX = "LPMSG_";
var ACTION_TYPE = {
TRIGGER: "trigger",
COMMAND: "command",
REQUEST: "request",
RETURN: "return"
};
var DEFAULT_TIMEOUT = 30 * 1000;
var DEFAULT_CONCURRENCY = 100;
var DEFAULT_MESSURE_TIME = 30 * 1000;
var DEFAULT_MESSURE_TOLERANCE = 30;
var DEFAULT_MESSURE_CALIBRATION = 10;
var CACHE_EVICTION_INTERVAL = 1000;
/**
* PostMessageCourier constructor
* @constructor
* @param {Object} options - the configuration options for the instance
* @param {Object} options.target - the target iframe or iframe configuration
* @param {String} [options.target.url] - the url to load
* @param {Object} [options.target.container] - the container in which the iframe should be created (if not supplied, document.body will be used)
* @param {String} [options.target.style] - the CSS style to apply
* @param {String} [options.target.style.width] width of iframe
* @param {String} [options.target.style.height] height of iframe
* .....
* @param {Boolean} [options.target.bust = true] - optional flag to indicate usage of cache buster when loading the iframe (default to true)
* @param {Function} [options.target.callback] - a callback to invoke after the iframe had been loaded
* @param {Object} [options.target.context] - optional context for the callback
* @param {Function|Object} [options.onready] - optional data for usage when iframe had been loaded
* @param {Function} [options.onready.callback] - a callback to invoke after the iframe had been loaded
* @param {Object} [options.onready.context] - optional context for the callback
* @param {Boolean} [options.removeDispose] - optional flag for removal of the iframe on dispose
* @param {Function} [options.serialize = JSON.stringify] - optional serialization method for post message
* @param {Function} [options.deserialize = JSON.parse] - optional deserialization method for post message
* @param {String} [options.targetOrigin] optional targetOrigin to be used when posting the message (must be supplied in case of external iframe)
* @param {Number} [options.maxConcurrency = 100] - optional maximum concurrency that can be managed by the component before dropping
* @param {Number} [options.handshakeInterval = 5000] - optional handshake interval for retries
* @param {Number} [options.handshakeAttempts = 3] - optional number of retries handshake attempts
* @param {String} [options.hostParam] - optional parameter of the host parameter name (default is lpHost)
* @param {Function} onmessage - the handler for incoming messages
* @param {Object} [options.eventChannel] - optional events channel to be used (if not supplied, a new one will be created OR optional events, optional commands, optional reqres to be used
* @param {Number} [options.timeout = 30000] - optional milliseconds parameter for waiting before timeout to responses (default is 30 seconds)
* @param {Number} [options.messureTime = 30000] - optional milliseconds parameter for time measurement indicating the time window to apply when implementing the internal fail fast mechanism (default is 30 seconds)
* @param {Number} [options.messureTolerance = 30] - optional percentage parameter indicating the tolerance to apply on the measurements when implementing the internal fail fast mechanism (default is 30 percents)
* @param {Number} [options.messureCalibration = 10] optional numeric parameter indicating the calibration of minimum calls before starting to validate measurements when implementing the internal fail fast mechanism (default is 10 calls)
* @param {Function} [options.ondisconnect] - optional disconnect handler that will be invoked when the fail fast mechanism disconnects the component upon to many failures
* @param {Function} [options.onreconnect] - optional reconnect handler that will be invoked when the fail fast mechanism reconnects the component upon back to normal behaviour
*
* @example
* var courier = new Chronos.PostMessageCourier({
* target: {
* url: "http://localhost/chronosjs/debug/courier.frame.html",
* style: {
* width: "100px",
* height: "100px"
* }
* }
* });
*/
function PostMessageCourier(options) {
// For forcing new keyword
/* istanbul ignore if */
if (false === (this instanceof PostMessageCourier)) {
return new PostMessageCourier(options);
}
this.initialize(options);
}
PostMessageCourier.prototype = (function () {
/**
* Method for initialization
* @param {Object} options - the configuration options for the instance
* @param {Object} options.target - the target iframe or iframe configuration
* @param {String} [options.target.url] - the url to load
* @param {Object} [options.target.container] - the container in which the iframe should be created (if not supplied, document.body will be used)
* @param {String} [options.target.style] - the CSS style to apply
* @param {String} [options.target.style.width] width of iframe
* @param {String} [options.target.style.height] height of iframe
* .....
* @param {Boolean} [options.target.bust = true] - optional flag to indicate usage of cache buster when loading the iframe (default to true)
* @param {Function} [options.target.callback] - a callback to invoke after the iframe had been loaded
* @param {Object} [options.target.context] - optional context for the callback
* @param {Function|Object} [options.onready] - optional data for usage when iframe had been loaded
* @param {Function} [options.onready.callback] - a callback to invoke after the iframe had been loaded
* @param {Object} [options.onready.context] - optional context for the callback
* @param {Boolean} [options.removeDispose] - optional flag for removal of the iframe on dispose
* @param {Function} [options.serialize = JSON.stringify] - optional serialization method for post message
* @param {Function} [options.deserialize = JSON.parse] - optional deserialization method for post message
* @param {String} [options.targetOrigin] optional targetOrigin to be used when posting the message (must be supplied in case of external iframe)
* @param {Number} [options.maxConcurrency = 100] - optional maximum concurrency that can be managed by the component before dropping
* @param {Number} [options.handshakeInterval = 5000] - optional handshake interval for retries
* @param {Number} [options.handshakeAttempts = 3] - optional number of retries handshake attempts
* @param {String} [options.hostParam] - optional parameter of the host parameter name (default is lpHost)
* @param {Function} onmessage - the handler for incoming messages
* @param {Boolean} [options.registerExternal] - allows registering external components for triggering to them as well
* @param {Object} [options.eventChannel] - optional events channel to be used (if not supplied, a new one will be created OR optional events, optional commands, optional reqres to be used
* @param {Number} [options.timeout = 30000] - optional milliseconds parameter for waiting before timeout to responses (default is 30 seconds)
* @param {Number} [options.messureTime = 30000] - optional milliseconds parameter for time measurement indicating the time window to apply when implementing the internal fail fast mechanism (default is 30 seconds)
* @param {Number} [options.messureTolerance = 30] - optional percentage parameter indicating the tolerance to apply on the measurements when implementing the internal fail fast mechanism (default is 30 percents)
* @param {Number} [options.messureCalibration = 10] optional numeric parameter indicating the calibration of minimum calls before starting to validate measurements when implementing the internal fail fast mechanism (default is 10 calls)
* @param {Function} [options.ondisconnect] - optional disconnect handler that will be invoked when the fail fast mechanism disconnects the component upon to many failures
* @param {Function} [options.onreconnect] - optional reconnect handler that will be invoked when the fail fast mechanism reconnects the component upon back to normal behaviour
*/
function initialize(options) {
if (!this.initialized) {
options = options || {};
// Init options for serialization of messages
_initializeSerialization.call(this, options);
// Init the communication components
_initializeCommunication.call(this, options);
// Init the cache for handling responses
_initializeCache.call(this, options);
// Init the fail fast mechanism which monitors responses
_initializeFailFast.call(this, options);
_registerProxy.call(this, this.eventChannel);
// Dumb Proxy methods
this.once = this.eventChannel.once;
this.hasFiredEvents = this.eventChannel.hasFiredEvents;
this.bind = this.eventChannel.bind;
this.register = this.eventChannel.register;
this.unbind = this.eventChannel.unbind;
this.unregister = this.eventChannel.unregister;
this.hasFiredCommands = this.eventChannel.hasFiredCommands;
this.comply = this.eventChannel.comply;
this.stopComplying = this.eventChannel.stopComplying;
this.hasFiredReqres = this.eventChannel.hasFiredReqres;
this.reply = this.eventChannel.reply;
this.stopReplying = this.eventChannel.stopReplying;
this.initialized = true;
}
}
/**
* Registers an external call to trigger for events to propagate calls to Channels.trigger automatically
* @param eventChannel
* @private
*/
function _registerProxy(eventChannel) {
if (eventChannel && "function" === typeof eventChannel.registerProxy) {
eventChannel.registerProxy({
trigger: function () {
_postMessage.call(this, Array.prototype.slice.apply(arguments), ACTION_TYPE.TRIGGER);
},
context: this
});
}
}
/**
* Method to get the member instance of the message channel
* @returns {PostMessageChannel} the member message channel
*/
function getMessageChannel() {
return this.messageChannel;
}
/**
* Method to get the member instance of the event channel
* @returns {Events} the member event channel
*/
function getEventChannel() {
return this.eventChannel;
}
/**
* Method to trigger event via post message
* @link Chronos.Events#trigger
* @param {Object|String} options - Configuration object or app name
* @param {String} [options.eventName] - the name of the event triggered
* @param {String} [options.appName] - optional specifies the identifier it is bound to
* @param {Boolean} [options.passDataByRef = false] - boolean flag whether this callback will get the reference information of the event or a copy (this allows control of data manipulation)
* @param {Object} [options.data] - optional event parameters to be passed to the listeners
* @param {String|Boolean} [evName] - the name of the event triggered || [noLocal] - optional boolean flag indicating whether to trigger the event on the local event channel too
* @param {Object} [data] - optional event parameters to be passed to the listeners
* @param {Boolean} [noLocal] - optional boolean flag indicating whether to trigger the event on the local event channel too
* @returns {*}
*
* @example
* courier.trigger({
* appName: "frame",
* eventName: "got_it",
* data: 2
* });
*/
function trigger() {
if (!this.disposed) {
var args = Array.prototype.slice.apply(arguments);
// We are looking for a "noLocal" param which can only be second or forth
// And only if its value is true, we will not trigger the event on the local event channel
if (!((2 === arguments.length || 4 === arguments.length) &&
true === arguments[arguments.length - 1])) {
this.eventChannel.trigger.apply(this.eventChannel, args);
}
return _postMessage.call(this, args, ACTION_TYPE.TRIGGER);
}
}
/**
* Method to trigger a command via post message
* @link Chronos.Commands#command
* @param {Object|String} options - Configuration object or app name
* @param {String} [options.cmdName] - the name of the command triggered
* @param {String} [options.appName] - optional specifies the identifier it is bound to
* @param {Boolean} [options.passDataByRef = false] - boolean flag whether this callback will get the reference information of the event or a copy (this allows control of data manipulation)
* @param {Object} [options.data] - optional event parameters to be passed to the listeners
* @param {Function} [callback] - optional callback method to be triggered when the command had finished executing
* @returns {*}
*
* @example
* courier.command({
* appName: "frame",
* cmdName: "expect",
* data: data
* }, function(err) {
* if (err) {
* console.log("Problem invoking command");
* }
* });
*/
function command() {
if (!this.disposed) {
var args = Array.prototype.slice.apply(arguments);
return _postMessage.call(this, args, ACTION_TYPE.COMMAND);
}
}
/**
* Method to trigger a request via post message
* @link Chronos.ReqRes#request
* @param {Object|String} options - Configuration object or app name
* @param {String} [options.reqName] - the name of the request triggered
* @param {String} [options.appName] - optional specifies the identifier it is bound to
* @param {Boolean} [options.passDataByRef = false] - boolean flag whether this callback will get the reference information of the event or a copy (this allows control of data manipulation)
* @param {Object} [options.data] - optional event parameters to be passed to the listeners
* @param {Function} [callback] - optional callback method to be triggered when the command had finished executing
* @return {*}
*
* @example
* courier.request({
* appName: "iframe",
* reqName: "Ma Shlomha?",
* data: data
* }, function(err, data) {
* if (err) {
* console.log("Problem invoking request");
* return;
* }
*
* // Do Something with data
* });
*/
function request() {
if (!this.disposed) {
var args = Array.prototype.slice.apply(arguments);
return _postMessage.call(this, args, ACTION_TYPE.REQUEST);
}
}
/**
* Method for disposing the object
*/
function dispose() {
if (!this.disposed) {
this.messageChannel.dispose();
this.messageChannel = void 0;
this.eventChannel = void 0;
this.mapper = void 0;
this.callbackCache = void 0;
this.circuit = void 0;
this.disposed = true;
}
}
/**
* Method for initializing the options for serialization of messages
* @param {Boolean} [options.useObjects = true upon browser support] - optional indication for passing objects by reference
* @param {Function} [options.serialize = JSON.stringify] - optional serialization method for post message
* @param {Function} [options.deserialize = JSON.parse] - optional deserialization method for post message
* @private
*/
function _initializeSerialization(options) {
this.useObjects = false === options.useObjects ? options.useObjects : _getUseObjectsUrlIndicator();
if ("undefined" === typeof this.useObjects) {
// Defaults to true
this.useObjects = true;
}
options.useObjects = this.useObjects;
// Define the serialize/deserialize methods to be used
if ("function" !== typeof options.serialize || "function" !== typeof options.deserialize) {
if (this.useObjects && PostMessageUtilities.hasPostMessageObjectsSupport()) {
this.serialize = _de$serializeDummy;
this.deserialize = _de$serializeDummy;
}
else {
this.serialize = PostMessageUtilities.stringify;
this.deserialize = JSON.parse;
}
options.serialize = this.serialize;
options.deserialize = this.deserialize;
}
else {
this.serialize = options.serialize;
this.deserialize = options.deserialize;
}
}
/**
* Method for initializing the communication elements
* @param {Object} [options.eventChannel] - optional events channel to be used (if not supplied, a new one will be created OR optional events, optional commands, optional reqres to be used
* @private
*/
function _initializeCommunication(options) {
var mapping;
var onmessage;
// Grab the event channel and initialize a new mapper
this.eventChannel = options.eventChannel || new Channels({
events: options.events,
commands: options.commands,
reqres: options.reqres
});
this.mapper = new PostMessageMapper(this.eventChannel);
// Bind the mapping method to the mapper
mapping = this.mapper.toEvent.bind(this.mapper);
// Create the message handler which uses the mapping method
onmessage = _createMessageHandler(mapping).bind(this);
// Initialize a message channel with the message handler
this.messageChannel = new PostMessageChannel(options, onmessage);
}
/**
* Method for initializing the cache for responses
* @param {Number} [options.maxConcurrency = 100] - optional maximum concurrency that can be managed by the component before dropping
* @param {Number} [options.timeout = 30000] - optional milliseconds parameter for waiting before timeout to responses (default is 30 seconds)
* @private
*/
function _initializeCache(options) {
this.callbackCache = new Cacher({
max: PostMessageUtilities.parseNumber(options.maxConcurrency, DEFAULT_CONCURRENCY),
ttl: PostMessageUtilities.parseNumber(options.timeout, DEFAULT_TIMEOUT),
interval: CACHE_EVICTION_INTERVAL
});
}
/**
* Method for initializing the fail fast mechanisms
* @param {Number} [options.messureTime = 30000] - optional milliseconds parameter for time measurement indicating the time window to apply when implementing the internal fail fast mechanism (default is 30 seconds)
* @param {Number} [options.messureTolerance = 30] - optional percentage parameter indicating the tolerance to apply on the measurements when implementing the internal fail fast mechanism (default is 30 percents)
* @param {Number} [options.messureCalibration = 10] optional numeric parameter indicating the calibration of minimum calls before starting to validate measurements when implementing the internal fail fast mechanism (default is 10 calls)
* @param {Function} [options.ondisconnect] - optional disconnect handler that will be invoked when the fail fast mechanism disconnects the component upon to many failures
* @param {Function} [options.onreconnect] - optional reconnect handler that will be invoked when the fail fast mechanism reconnects the component upon back to normal behaviour
* @private
*/
function _initializeFailFast(options) {
var messureTime = PostMessageUtilities.parseNumber(options.messureTime, DEFAULT_MESSURE_TIME);
this.circuit = new CircuitBreaker({
timeWindow: messureTime,
slidesNumber: Math.ceil(messureTime / 100),
tolerance: PostMessageUtilities.parseNumber(options.messureTolerance, DEFAULT_MESSURE_TOLERANCE),
calibration: PostMessageUtilities.parseNumber(options.messureCalibration, DEFAULT_MESSURE_CALIBRATION),
onopen: PostMessageUtilities.parseFunction(options.ondisconnect, true),
onclose: PostMessageUtilities.parseFunction(options.onreconnect, true)
});
}
/**
* Method to get url indication for using serialization/deserialization
* @returns {Boolean} indication for serialization/deserialization usage
* @private
*/
function _getUseObjectsUrlIndicator() {
var deserialize = PostMessageUtilities.getURLParameter("lpPMDeSerialize");
if ("true" === deserialize) {
return false;
}
}
/**
* Just a dummy serialization/deserialization method for browsers supporting objects with postMessage API
* @param {Object} object - the object to (NOT) serialize/deserialize.
* @returns {Object} The same object
*/
function _de$serializeDummy(object) {
return object;
}
/**
* Method for posting the message via the circuit breaker
* @param {Array} args - the arguments for the message to be processed.
* @param {String} name - name of type of command.
* @private
*/
function _postMessage(args, name) {
return this.circuit.run(function (success, failure, timeout) {
var message = _prepare.call(this, args, name, timeout);
if (message) {
try {
var initiated = this.messageChannel.postMessage.call(this.messageChannel, message);
if (false === initiated) {
failure();
}
else {
success();
}
}
catch (ex) {
failure();
}
}
else {
// Cache is full, as a fail fast mechanism, we should not continue
failure();
}
}.bind(this));
}
/**
* Method for posting the returned message via the circuit breaker
* @param {Object} message - the message to post.
* @param {bject} [target] - optional target for post.
* @private
*/
function _returnMessage(message, target) {
return this.circuit.run(function (success, failure) {
try {
var initiated = this.messageChannel.postMessage.call(this.messageChannel, message, target);
if (false === initiated) {
failure();
}
else {
success();
}
}
catch (ex) {
failure();
}
}.bind(this));
}
/**
* Method for preparing the message to be posted via the postmessage and caching the callback to be called if needed
* @param {Array} args - the arguments to pass to the message mapper
* @param {String} name - the action type name (trigger, command, request)
* @param {Function} [ontimeout] - the ontimeout measurement handler
* @returns {Function} handler function for messages
* @private
*/
function _prepare(args, name, ontimeout) {
var method;
var ttl;
var id = PostMessageUtilities.createUniqueSequence(MESSAGE_PREFIX + name + PostMessageUtilities.SEQUENCE_FORMAT);
args.unshift(id, name);
if (_isTwoWay(name)) {
if (1 < args.length && "function" === typeof args[args.length - 1]) {
method = args.pop();
}
else if (2 < args.length && !isNaN(args[args.length - 1]) && "function" === typeof args[args.length - 2]) {
ttl = parseInt(args.pop(), 10);
method = args.pop();
}
if (method) {
if (!this.callbackCache.set(id, method, ttl, function (id, callback) {
ontimeout();
_handleTimeout.call(this, id, callback);
}.bind(this))) {
// Cache is full, as a fail fast mechanism, we will not continue
return void 0;
}
}
}
return this.mapper.toMessage.apply(this.mapper, args);
}
/**
* Method for checking two way communication for action
* @param {PostMessageCourier.ACTION_TYPE} action - the action type name
* @returns {Boolean} flag to indicate whether the action is two way (had return call)
* @private
*/
function _isTwoWay(action) {
return ACTION_TYPE.REQUEST === action || ACTION_TYPE.COMMAND === action;
}
/**
* Method for handling timeout of a cached callback
* @param {String} id - the id of the timed out callback
* @param {Function} callback - the callback object from cache
* @private
*/
function _handleTimeout(id, callback) {
// Handle timeout
if (id && "function" === typeof callback) {
try {
callback.call(null, new Error("Callback: Operation Timeout!"));
}
catch (ex) {
/* istanbul ignore next */
PostMessageUtilities.log("Error while trying to handle the timeout using the callback", "ERROR", "PostMessageCourier");
}
}
}
/**
* Method for handling return messages from the callee
* @param {String} id - the id of the callback
* @param {Object} method - the method object with needed args
* @private
*/
function _handleReturnMessage(id, method) {
var callback = this.callbackCache.get(id, true);
var args = method && method.args;
if ("function" === typeof callback) {
// First try to parse the first parameter in case the error is an object
if (args && args.length && args[0] && "Error" === args[0].type && "string" === typeof args[0].message) {
args[0] = new Error(args[0].message);
}
try {
callback.apply(null, args);
}
catch (ex) {
PostMessageUtilities.log("Error while trying to handle the returned message from request/command", "ERROR", "PostMessageCourier");
}
}
}
/**
* Method for creation of a return message handler from the callee
* @param {String} id - the id of the message
* @param {String} name - message name
* @param {Object} message - original message structure
* @private
*/
function _getReturnMessageHandler(id, name, message) {
/* istanbul ignore next: it is being covered at the iframe side - cannot add it to coverage matrix */
return function(err, result) {
var retMsg;
var params;
var error = err;
// In case of Error Object, create a special object that can be parsed
if (err instanceof Error) {
error = {
type: "Error",
message: err.message
};
}
// Call the mapping method to receive the message structure
params = [id, ACTION_TYPE.RETURN, error];
if (ACTION_TYPE.REQUEST === name) {
params.push(result);
}
retMsg = this.mapper.toMessage.apply(this.mapper, params);
// Post the message
_returnMessage.call(this, retMsg, message.source);
}.bind(this);
}
/**
* Method for handling the result of the call (this can be the response or a defer/promise)
* @param {String} id - the id of the message
* @param {String} name - message name
* @param {Object} result - the result object
* @param {Object} message - original message structure
* @private
*/
function _handleResult(id, name, result, message) {
var retMsg;
var params;
// If the result is async (promise) we need to defer the execution of the results data
if (("undefined" !== typeof Promise && result instanceof Promise) || result instanceof PostMessagePromise) {
// Handle async using promises
result.then(function (data) {
params = [id, ACTION_TYPE.RETURN, null];
if (ACTION_TYPE.REQUEST === name) {
params.push(data);
}
// Call the mapping method to receive the message structure
retMsg = this.mapper.toMessage.apply(this.mapper, params);
// Post the message
_returnMessage.call(this, retMsg, message.source);
}.bind(this), function (data) {
params = [id, ACTION_TYPE.RETURN, data];
// Call the mapping method to receive the message structure
retMsg = this.mapper.toMessage.apply(this.mapper, params);
// Post the message
_returnMessage.call(this, retMsg, message.source);
}.bind(this));
}
else {
if (result && result.error) {
params = [id, ACTION_TYPE.RETURN, result];
// Call the mapping method to receive the message structure
retMsg = this.mapper.toMessage.apply(this.mapper, params);
// Post the message
_returnMessage.call(this, retMsg, message.source);
}
else if ("undefined" !== typeof result) {
params = [id, ACTION_TYPE.RETURN, null];
if (ACTION_TYPE.REQUEST === name) {
params.push(result);
}
// Call the mapping method to receive the message structure
retMsg = this.mapper.toMessage.apply(this.mapper, params);
// Post the message
_returnMessage.call(this, retMsg, message.source);
}
}
}
/**
* Method for wrapping the handler of the postmessage for parsing
* @param {Object} mapping - the handler for incoming messages to invoke which maps the message to event
* @returns {Function} handler function for messages
* @private
*/
function _createMessageHandler(mapping) {
return function(message) {
var handler;
var result;
var params;
var retMsg;
var id;
var name;
var args;
if (message) {
id = message.method && message.method.id;
name = message.method && message.method.name;
args = message.method && message.method.args;
// In case the message is a return value from a request/response call
// It is marked as a "return" message and we need to call the supplied cached callback
if (ACTION_TYPE.RETURN === name) {
_handleReturnMessage.call(this, id, message.method);
}
else {
// Call the mapping method to receive the handling method on the event channel
// Invoke the handling method
try {
if (_isTwoWay(name)) {
if (args.length) {
args.push(_getReturnMessageHandler.call(this, id, name, message));
}
}
handler = mapping(message);
result = handler && handler();
}
catch (ex) {
/* istanbul ignore next: special handling for other implementations of channels which does not catch exceptions from triggers (like backbone) - when working with chronos channels it will not be called */
PostMessageUtilities.log("Error while trying to invoke the handler on the events channel", "ERROR", "PostMessageCourier");
/* istanbul ignore next: special handling for other implementations of channels which does not catch exceptions from triggers (like backbone) - when working with chronos channels it will not be called */
if (_isTwoWay(name)) {
params = [id, ACTION_TYPE.RETURN, {error: ex.toString()}];
retMsg = this.mapper.toMessage.apply(this.mapper, params);
_returnMessage.call(this, retMsg, message.source);
}
}
// In case the method is two way and returned a result
if (_isTwoWay(name) && "undefined" !== typeof result) {
_handleResult.call(this, id, name, result, message);
}
}
}
};
}
return {
initialize: initialize,
getMessageChannel: getMessageChannel,
getEventChannel: getEventChannel,
trigger: trigger,
publish: trigger,
command: command,
request: request,
dispose: dispose
};
}());
// attach properties to the exports object to define
// the exported module properties.
if (!hide) {
exports.PostMessageCourier = exports.PostMessageCourier || PostMessageCourier;
}
return PostMessageCourier;
}));