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authorEvan Prodromou <evan@controlyourself.ca>2009-06-30 23:33:47 -0400
committerEvan Prodromou <evan@status.net>2009-10-04 03:15:59 -0400
commit22b4a66de3441bcb54b748f98be5b53e3be4bece (patch)
tree5c7c2f32dd5e228186c578004db2bcd439feae0a /plugins/Orbited/jquery.comet.js
parent9c460d591e1e11f7aa3970ffd0b3e320dd11d33e (diff)
copy Comet plugin to Orbited
Diffstat (limited to 'plugins/Orbited/jquery.comet.js')
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diff --git a/plugins/Orbited/jquery.comet.js b/plugins/Orbited/jquery.comet.js
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+/**
+ * Copyright 2008 Mort Bay Consulting Pty. Ltd.
+ * Dual licensed under the Apache License 2.0 and the MIT license.
+ * ----------------------------------------------------------------------------
+ * 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.
+ * ----------------------------------------------------------------------------
+ * Licensed under the MIT license;
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * ----------------------------------------------------------------------------
+ * $Revision$ $Date$
+ */
+(function($)
+{
+ /**
+ * The constructor for a Comet object.
+ * There is a default Comet instance already created at the variable <code>$.cometd</code>,
+ * and hence that can be used to start a comet conversation with a server.
+ * In the rare case a page needs more than one comet conversation, a new instance can be
+ * created via:
+ * <pre>
+ * var url2 = ...;
+ * var cometd2 = new $.Cometd();
+ * cometd2.init(url2);
+ * </pre>
+ */
+ $.Cometd = function(name)
+ {
+ var _name = name || 'default';
+ var _logPriorities = { debug: 1, info: 2, warn: 3, error: 4 };
+ var _logLevel = 'info';
+ var _url;
+ var _xd = false;
+ var _transport;
+ var _status = 'disconnected';
+ var _messageId = 0;
+ var _clientId = null;
+ var _batch = 0;
+ var _messageQueue = [];
+ var _listeners = {};
+ var _backoff = 0;
+ var _backoffIncrement = 1000;
+ var _maxBackoff = 60000;
+ var _scheduledSend = null;
+ var _extensions = [];
+ var _advice = {};
+ var _handshakeProps;
+
+ /**
+ * Returns the name assigned to this Comet object, or the string 'default'
+ * if no name has been explicitely passed as parameter to the constructor.
+ */
+ this.getName = function()
+ {
+ return _name;
+ };
+
+ /**
+ * Configures the initial comet communication with the comet server.
+ * @param cometURL the URL of the comet server
+ */
+ this.configure = function(cometURL)
+ {
+ _configure(cometURL);
+ };
+
+ function _configure(cometURL)
+ {
+ _url = cometURL;
+ _debug('Initializing comet with url: {}', _url);
+
+ // Check immediately if we're cross domain
+ // If cross domain, the handshake must not send the long polling transport type
+ var urlParts = /(^https?:)?(\/\/(([^:\/\?#]+)(:(\d+))?))?([^\?#]*)/.exec(cometURL);
+ if (urlParts[3]) _xd = urlParts[3] != location.host;
+
+ // Temporary setup a transport to send the initial handshake
+ // The transport may be changed as a result of handshake
+ if (_xd)
+ _transport = newCallbackPollingTransport();
+ else
+ _transport = newLongPollingTransport();
+ _debug('Initial transport is {}', _transport.getType());
+ };
+
+ /**
+ * Configures and establishes the comet communication with the comet server
+ * via a handshake and a subsequent connect.
+ * @param cometURL the URL of the comet server
+ * @param handshakeProps an object to be merged with the handshake message
+ * @see #configure(cometURL)
+ * @see #handshake(handshakeProps)
+ */
+ this.init = function(cometURL, handshakeProps)
+ {
+ _configure(cometURL);
+ _handshake(handshakeProps);
+ };
+
+ /**
+ * Establishes the comet communication with the comet server
+ * via a handshake and a subsequent connect.
+ * @param handshakeProps an object to be merged with the handshake message
+ */
+ this.handshake = function(handshakeProps)
+ {
+ _handshake(handshakeProps);
+ };
+
+ /**
+ * Disconnects from the comet server.
+ * @param disconnectProps an object to be merged with the disconnect message
+ */
+ this.disconnect = function(disconnectProps)
+ {
+ var bayeuxMessage = {
+ channel: '/meta/disconnect'
+ };
+ var message = $.extend({}, disconnectProps, bayeuxMessage);
+ // Deliver immediately
+ // The handshake and connect mechanism make use of startBatch(), and in case
+ // of a failed handshake the disconnect would not be delivered if using _send().
+ _setStatus('disconnecting');
+ _deliver([message], false);
+ };
+
+ /**
+ * Marks the start of a batch of application messages to be sent to the server
+ * in a single request, obtaining a single response containing (possibly) many
+ * application reply messages.
+ * Messages are held in a queue and not sent until {@link #endBatch()} is called.
+ * If startBatch() is called multiple times, then an equal number of endBatch()
+ * calls must be made to close and send the batch of messages.
+ * @see #endBatch()
+ */
+ this.startBatch = function()
+ {
+ _startBatch();
+ };
+
+ /**
+ * Marks the end of a batch of application messages to be sent to the server
+ * in a single request.
+ * @see #startBatch()
+ */
+ this.endBatch = function()
+ {
+ _endBatch(true);
+ };
+
+ /**
+ * Subscribes to the given channel, performing the given callback in the given scope
+ * when a message for the channel arrives.
+ * @param channel the channel to subscribe to
+ * @param scope the scope of the callback
+ * @param callback the callback to call when a message is delivered to the channel
+ * @param subscribeProps an object to be merged with the subscribe message
+ * @return the subscription handle to be passed to {@link #unsubscribe(object)}
+ */
+ this.subscribe = function(channel, scope, callback, subscribeProps)
+ {
+ var subscription = this.addListener(channel, scope, callback);
+
+ // Send the subscription message after the subscription registration to avoid
+ // races where the server would deliver a message to the subscribers, but here
+ // on the client the subscription has not been added yet to the data structures
+ var bayeuxMessage = {
+ channel: '/meta/subscribe',
+ subscription: channel
+ };
+ var message = $.extend({}, subscribeProps, bayeuxMessage);
+ _send(message);
+
+ return subscription;
+ };
+
+ /**
+ * Unsubscribes the subscription obtained with a call to {@link #subscribe(string, object, function)}.
+ * @param subscription the subscription to unsubscribe.
+ */
+ this.unsubscribe = function(subscription, unsubscribeProps)
+ {
+ // Remove the local listener before sending the message
+ // This ensures that if the server fails, this client does not get notifications
+ this.removeListener(subscription);
+ var bayeuxMessage = {
+ channel: '/meta/unsubscribe',
+ subscription: subscription[0]
+ };
+ var message = $.extend({}, unsubscribeProps, bayeuxMessage);
+ _send(message);
+ };
+
+ /**
+ * Publishes a message on the given channel, containing the given content.
+ * @param channel the channel to publish the message to
+ * @param content the content of the message
+ * @param publishProps an object to be merged with the publish message
+ */
+ this.publish = function(channel, content, publishProps)
+ {
+ var bayeuxMessage = {
+ channel: channel,
+ data: content
+ };
+ var message = $.extend({}, publishProps, bayeuxMessage);
+ _send(message);
+ };
+
+ /**
+ * Adds a listener for bayeux messages, performing the given callback in the given scope
+ * when a message for the given channel arrives.
+ * @param channel the channel the listener is interested to
+ * @param scope the scope of the callback
+ * @param callback the callback to call when a message is delivered to the channel
+ * @returns the subscription handle to be passed to {@link #removeListener(object)}
+ * @see #removeListener(object)
+ */
+ this.addListener = function(channel, scope, callback)
+ {
+ // The data structure is a map<channel, subscription[]>, where each subscription
+ // holds the callback to be called and its scope.
+
+ // Normalize arguments
+ if (!callback)
+ {
+ callback = scope;
+ scope = undefined;
+ }
+
+ var subscription = {
+ scope: scope,
+ callback: callback
+ };
+
+ var subscriptions = _listeners[channel];
+ if (!subscriptions)
+ {
+ subscriptions = [];
+ _listeners[channel] = subscriptions;
+ }
+ // Pushing onto an array appends at the end and returns the id associated with the element increased by 1.
+ // Note that if:
+ // a.push('a'); var hb=a.push('b'); delete a[hb-1]; var hc=a.push('c');
+ // then:
+ // hc==3, a.join()=='a',,'c', a.length==3
+ var subscriptionIndex = subscriptions.push(subscription) - 1;
+ _debug('Added listener: channel \'{}\', callback \'{}\', index {}', channel, callback.name, subscriptionIndex);
+
+ // The subscription to allow removal of the listener is made of the channel and the index
+ return [channel, subscriptionIndex];
+ };
+
+ /**
+ * Removes the subscription obtained with a call to {@link #addListener(string, object, function)}.
+ * @param subscription the subscription to unsubscribe.
+ */
+ this.removeListener = function(subscription)
+ {
+ var subscriptions = _listeners[subscription[0]];
+ if (subscriptions)
+ {
+ delete subscriptions[subscription[1]];
+ _debug('Removed listener: channel \'{}\', index {}', subscription[0], subscription[1]);
+ }
+ };
+
+ /**
+ * Removes all listeners registered with {@link #addListener(channel, scope, callback)} or
+ * {@link #subscribe(channel, scope, callback)}.
+ */
+ this.clearListeners = function()
+ {
+ _listeners = {};
+ };
+
+ /**
+ * Returns a string representing the status of the bayeux communication with the comet server.
+ */
+ this.getStatus = function()
+ {
+ return _status;
+ };
+
+ /**
+ * Sets the backoff period used to increase the backoff time when retrying an unsuccessful or failed message.
+ * Default value is 1 second, which means if there is a persistent failure the retries will happen
+ * after 1 second, then after 2 seconds, then after 3 seconds, etc. So for example with 15 seconds of
+ * elapsed time, there will be 5 retries (at 1, 3, 6, 10 and 15 seconds elapsed).
+ * @param period the backoff period to set
+ * @see #getBackoffIncrement()
+ */
+ this.setBackoffIncrement = function(period)
+ {
+ _backoffIncrement = period;
+ };
+
+ /**
+ * Returns the backoff period used to increase the backoff time when retrying an unsuccessful or failed message.
+ * @see #setBackoffIncrement(period)
+ */
+ this.getBackoffIncrement = function()
+ {
+ return _backoffIncrement;
+ };
+
+ /**
+ * Returns the backoff period to wait before retrying an unsuccessful or failed message.
+ */
+ this.getBackoffPeriod = function()
+ {
+ return _backoff;
+ };
+
+ /**
+ * Sets the log level for console logging.
+ * Valid values are the strings 'error', 'warn', 'info' and 'debug', from
+ * less verbose to more verbose.
+ * @param level the log level string
+ */
+ this.setLogLevel = function(level)
+ {
+ _logLevel = level;
+ };
+
+ /**
+ * Registers an extension whose callbacks are called for every incoming message
+ * (that comes from the server to this client implementation) and for every
+ * outgoing message (that originates from this client implementation for the
+ * server).
+ * The format of the extension object is the following:
+ * <pre>
+ * {
+ * incoming: function(message) { ... },
+ * outgoing: function(message) { ... }
+ * }
+ * Both properties are optional, but if they are present they will be called
+ * respectively for each incoming message and for each outgoing message.
+ * </pre>
+ * @param name the name of the extension
+ * @param extension the extension to register
+ * @return true if the extension was registered, false otherwise
+ * @see #unregisterExtension(name)
+ */
+ this.registerExtension = function(name, extension)
+ {
+ var existing = false;
+ for (var i = 0; i < _extensions.length; ++i)
+ {
+ var existingExtension = _extensions[i];
+ if (existingExtension.name == name)
+ {
+ existing = true;
+ return false;
+ }
+ }
+ if (!existing)
+ {
+ _extensions.push({
+ name: name,
+ extension: extension
+ });
+ _debug('Registered extension \'{}\'', name);
+ return true;
+ }
+ else
+ {
+ _info('Could not register extension with name \'{}\': another extension with the same name already exists');
+ return false;
+ }
+ };
+
+ /**
+ * Unregister an extension previously registered with
+ * {@link #registerExtension(name, extension)}.
+ * @param name the name of the extension to unregister.
+ * @return true if the extension was unregistered, false otherwise
+ */
+ this.unregisterExtension = function(name)
+ {
+ var unregistered = false;
+ $.each(_extensions, function(index, extension)
+ {
+ if (extension.name == name)
+ {
+ _extensions.splice(index, 1);
+ unregistered = true;
+ _debug('Unregistered extension \'{}\'', name);
+ return false;
+ }
+ });
+ return unregistered;
+ };
+
+ /**
+ * Starts a the batch of messages to be sent in a single request.
+ * @see _endBatch(deliverMessages)
+ */
+ function _startBatch()
+ {
+ ++_batch;
+ };
+
+ /**
+ * Ends the batch of messages to be sent in a single request,
+ * optionally delivering messages present in the message queue depending
+ * on the given argument.
+ * @param deliverMessages whether to deliver the messages in the queue or not
+ * @see _startBatch()
+ */
+ function _endBatch(deliverMessages)
+ {
+ --_batch;
+ if (_batch < 0) _batch = 0;
+ if (deliverMessages && _batch == 0 && !_isDisconnected())
+ {
+ var messages = _messageQueue;
+ _messageQueue = [];
+ if (messages.length > 0) _deliver(messages, false);
+ }
+ };
+
+ function _nextMessageId()
+ {
+ return ++_messageId;
+ };
+
+ /**
+ * Converts the given response into an array of bayeux messages
+ * @param response the response to convert
+ * @return an array of bayeux messages obtained by converting the response
+ */
+ function _convertToMessages(response)
+ {
+ if (response === undefined) return [];
+ if (response instanceof Array) return response;
+ if (response instanceof String || typeof response == 'string') return eval('(' + response + ')');
+ if (response instanceof Object) return [response];
+ throw 'Conversion Error ' + response + ', typeof ' + (typeof response);
+ };
+
+ function _setStatus(newStatus)
+ {
+ _debug('{} -> {}', _status, newStatus);
+ _status = newStatus;
+ };
+
+ function _isDisconnected()
+ {
+ return _status == 'disconnecting' || _status == 'disconnected';
+ };
+
+ /**
+ * Sends the initial handshake message
+ */
+ function _handshake(handshakeProps)
+ {
+ _debug('Starting handshake');
+ _clientId = null;
+
+ // Start a batch.
+ // This is needed because handshake and connect are async.
+ // It may happen that the application calls init() then subscribe()
+ // and the subscribe message is sent before the connect message, if
+ // the subscribe message is not held until the connect message is sent.
+ // So here we start a batch to hold temporarly any message until
+ // the connection is fully established.
+ _batch = 0;
+ _startBatch();
+
+ // Save the original properties provided by the user
+ // Deep copy to avoid the user to be able to change them later
+ _handshakeProps = $.extend(true, {}, handshakeProps);
+
+ var bayeuxMessage = {
+ version: '1.0',
+ minimumVersion: '0.9',
+ channel: '/meta/handshake',
+ supportedConnectionTypes: _xd ? ['callback-polling'] : ['long-polling', 'callback-polling']
+ };
+ // Do not allow the user to mess with the required properties,
+ // so merge first the user properties and *then* the bayeux message
+ var message = $.extend({}, handshakeProps, bayeuxMessage);
+
+ // We started a batch to hold the application messages,
+ // so here we must bypass it and deliver immediately.
+ _setStatus('handshaking');
+ _deliver([message], false);
+ };
+
+ function _findTransport(handshakeResponse)
+ {
+ var transportTypes = handshakeResponse.supportedConnectionTypes;
+ if (_xd)
+ {
+ // If we are cross domain, check if the server supports it, that's the only option
+ if ($.inArray('callback-polling', transportTypes) >= 0) return _transport;
+ }
+ else
+ {
+ // Check if we can keep long-polling
+ if ($.inArray('long-polling', transportTypes) >= 0) return _transport;
+
+ // The server does not support long-polling
+ if ($.inArray('callback-polling', transportTypes) >= 0) return newCallbackPollingTransport();
+ }
+ return null;
+ };
+
+ function _delayedHandshake()
+ {
+ _setStatus('handshaking');
+ _delayedSend(function()
+ {
+ _handshake(_handshakeProps);
+ });
+ };
+
+ function _delayedConnect()
+ {
+ _setStatus('connecting');
+ _delayedSend(function()
+ {
+ _connect();
+ });
+ };
+
+ function _delayedSend(operation)
+ {
+ _cancelDelayedSend();
+ var delay = _backoff;
+ _debug("Delayed send: backoff {}, interval {}", _backoff, _advice.interval);
+ if (_advice.interval && _advice.interval > 0)
+ delay += _advice.interval;
+ _scheduledSend = _setTimeout(operation, delay);
+ };
+
+ function _cancelDelayedSend()
+ {
+ if (_scheduledSend !== null) clearTimeout(_scheduledSend);
+ _scheduledSend = null;
+ };
+
+ function _setTimeout(funktion, delay)
+ {
+ return setTimeout(function()
+ {
+ try
+ {
+ funktion();
+ }
+ catch (x)
+ {
+ _debug('Exception during scheduled execution of function \'{}\': {}', funktion.name, x);
+ }
+ }, delay);
+ };
+
+ /**
+ * Sends the connect message
+ */
+ function _connect()
+ {
+ _debug('Starting connect');
+ var message = {
+ channel: '/meta/connect',
+ connectionType: _transport.getType()
+ };
+ _setStatus('connecting');
+ _deliver([message], true);
+ _setStatus('connected');
+ };
+
+ function _send(message)
+ {
+ if (_batch > 0)
+ _messageQueue.push(message);
+ else
+ _deliver([message], false);
+ };
+
+ /**
+ * Delivers the messages to the comet server
+ * @param messages the array of messages to send
+ */
+ function _deliver(messages, comet)
+ {
+ // We must be sure that the messages have a clientId.
+ // This is not guaranteed since the handshake may take time to return
+ // (and hence the clientId is not known yet) and the application
+ // may create other messages.
+ $.each(messages, function(index, message)
+ {
+ message['id'] = _nextMessageId();
+ if (_clientId) message['clientId'] = _clientId;
+ messages[index] = _applyOutgoingExtensions(message);
+ });
+
+ var self = this;
+ var envelope = {
+ url: _url,
+ messages: messages,
+ onSuccess: function(request, response)
+ {
+ try
+ {
+ _handleSuccess.call(self, request, response, comet);
+ }
+ catch (x)
+ {
+ _debug('Exception during execution of success callback: {}', x);
+ }
+ },
+ onFailure: function(request, reason, exception)
+ {
+ try
+ {
+ _handleFailure.call(self, request, messages, reason, exception, comet);
+ }
+ catch (x)
+ {
+ _debug('Exception during execution of failure callback: {}', x);
+ }
+ }
+ };
+ _debug('Sending request to {}, message(s): {}', envelope.url, JSON.stringify(envelope.messages));
+ _transport.send(envelope, comet);
+ };
+
+ function _applyIncomingExtensions(message)
+ {
+ for (var i = 0; i < _extensions.length; ++i)
+ {
+ var extension = _extensions[i];
+ var callback = extension.extension.incoming;
+ if (callback && typeof callback === 'function')
+ {
+ _debug('Calling incoming extension \'{}\', callback \'{}\'', extension.name, callback.name);
+ message = _applyExtension(extension.name, callback, message) || message;
+ }
+ }
+ return message;
+ };
+
+ function _applyOutgoingExtensions(message)
+ {
+ for (var i = 0; i < _extensions.length; ++i)
+ {
+ var extension = _extensions[i];
+ var callback = extension.extension.outgoing;
+ if (callback && typeof callback === 'function')
+ {
+ _debug('Calling outgoing extension \'{}\', callback \'{}\'', extension.name, callback.name);
+ message = _applyExtension(extension.name, callback, message) || message;
+ }
+ }
+ return message;
+ };
+
+ function _applyExtension(name, callback, message)
+ {
+ try
+ {
+ return callback(message);
+ }
+ catch (x)
+ {
+ _debug('Exception during execution of extension \'{}\': {}', name, x);
+ return message;
+ }
+ };
+
+ function _handleSuccess(request, response, comet)
+ {
+ var messages = _convertToMessages(response);
+ _debug('Received response {}', JSON.stringify(messages));
+
+ // Signal the transport it can deliver other queued requests
+ _transport.complete(request, true, comet);
+
+ for (var i = 0; i < messages.length; ++i)
+ {
+ var message = messages[i];
+ message = _applyIncomingExtensions(message);
+
+ if (message.advice) _advice = message.advice;
+
+ var channel = message.channel;
+ switch (channel)
+ {
+ case '/meta/handshake':
+ _handshakeSuccess(message);
+ break;
+ case '/meta/connect':
+ _connectSuccess(message);
+ break;
+ case '/meta/disconnect':
+ _disconnectSuccess(message);
+ break;
+ case '/meta/subscribe':
+ _subscribeSuccess(message);
+ break;
+ case '/meta/unsubscribe':
+ _unsubscribeSuccess(message);
+ break;
+ default:
+ _messageSuccess(message);
+ break;
+ }
+ }
+ };
+
+ function _handleFailure(request, messages, reason, exception, comet)
+ {
+ var xhr = request.xhr;
+ _debug('Request failed, status: {}, reason: {}, exception: {}', xhr && xhr.status, reason, exception);
+
+ // Signal the transport it can deliver other queued requests
+ _transport.complete(request, false, comet);
+
+ for (var i = 0; i < messages.length; ++i)
+ {
+ var message = messages[i];
+ var channel = message.channel;
+ switch (channel)
+ {
+ case '/meta/handshake':
+ _handshakeFailure(xhr, message);
+ break;
+ case '/meta/connect':
+ _connectFailure(xhr, message);
+ break;
+ case '/meta/disconnect':
+ _disconnectFailure(xhr, message);
+ break;
+ case '/meta/subscribe':
+ _subscribeFailure(xhr, message);
+ break;
+ case '/meta/unsubscribe':
+ _unsubscribeFailure(xhr, message);
+ break;
+ default:
+ _messageFailure(xhr, message);
+ break;
+ }
+ }
+ };
+
+ function _handshakeSuccess(message)
+ {
+ if (message.successful)
+ {
+ _debug('Handshake successful');
+ // Save clientId, figure out transport, then follow the advice to connect
+ _clientId = message.clientId;
+
+ var newTransport = _findTransport(message);
+ if (newTransport === null)
+ {
+ throw 'Could not agree on transport with server';
+ }
+ else
+ {
+ if (_transport.getType() != newTransport.getType())
+ {
+ _debug('Changing transport from {} to {}', _transport.getType(), newTransport.getType());
+ _transport = newTransport;
+ }
+ }
+
+ // Notify the listeners
+ // Here the new transport is in place, as well as the clientId, so
+ // the listener can perform a publish() if it wants, and the listeners
+ // are notified before the connect below.
+ _notifyListeners('/meta/handshake', message);
+
+ var action = _advice.reconnect ? _advice.reconnect : 'retry';
+ switch (action)
+ {
+ case 'retry':
+ _delayedConnect();
+ break;
+ default:
+ break;
+ }
+ }
+ else
+ {
+ _debug('Handshake unsuccessful');
+
+ var retry = !_isDisconnected() && _advice.reconnect != 'none';
+ if (!retry) _setStatus('disconnected');
+
+ _notifyListeners('/meta/handshake', message);
+ _notifyListeners('/meta/unsuccessful', message);
+
+ // Only try again if we haven't been disconnected and
+ // the advice permits us to retry the handshake
+ if (retry)
+ {
+ _increaseBackoff();
+ _debug('Handshake failure, backing off and retrying in {} ms', _backoff);
+ _delayedHandshake();
+ }
+ }
+ };
+
+ function _handshakeFailure(xhr, message)
+ {
+ _debug('Handshake failure');
+
+ // Notify listeners
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: '/meta/handshake',
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'retry',
+ interval: _backoff
+ }
+ };
+
+ var retry = !_isDisconnected() && _advice.reconnect != 'none';
+ if (!retry) _setStatus('disconnected');
+
+ _notifyListeners('/meta/handshake', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+
+ // Only try again if we haven't been disconnected and the
+ // advice permits us to try again
+ if (retry)
+ {
+ _increaseBackoff();
+ _debug('Handshake failure, backing off and retrying in {} ms', _backoff);
+ _delayedHandshake();
+ }
+ };
+
+ function _connectSuccess(message)
+ {
+ var action = _isDisconnected() ? 'none' : (_advice.reconnect ? _advice.reconnect : 'retry');
+ if (!_isDisconnected()) _setStatus(action == 'retry' ? 'connecting' : 'disconnecting');
+
+ if (message.successful)
+ {
+ _debug('Connect successful');
+
+ // End the batch and allow held messages from the application
+ // to go to the server (see _handshake() where we start the batch).
+ // The batch is ended before notifying the listeners, so that
+ // listeners can batch other cometd operations
+ _endBatch(true);
+
+ // Notify the listeners after the status change but before the next connect
+ _notifyListeners('/meta/connect', message);
+
+ // Connect was successful.
+ // Normally, the advice will say "reconnect: 'retry', interval: 0"
+ // and the server will hold the request, so when a response returns
+ // we immediately call the server again (long polling)
+ switch (action)
+ {
+ case 'retry':
+ _resetBackoff();
+ _delayedConnect();
+ break;
+ default:
+ _resetBackoff();
+ _setStatus('disconnected');
+ break;
+ }
+ }
+ else
+ {
+ _debug('Connect unsuccessful');
+
+ // Notify the listeners after the status change but before the next action
+ _notifyListeners('/meta/connect', message);
+ _notifyListeners('/meta/unsuccessful', message);
+
+ // Connect was not successful.
+ // This may happen when the server crashed, the current clientId
+ // will be invalid, and the server will ask to handshake again
+ switch (action)
+ {
+ case 'retry':
+ _increaseBackoff();
+ _delayedConnect();
+ break;
+ case 'handshake':
+ // End the batch but do not deliver the messages until we connect successfully
+ _endBatch(false);
+ _resetBackoff();
+ _delayedHandshake();
+ break;
+ case 'none':
+ _resetBackoff();
+ _setStatus('disconnected');
+ break;
+ }
+ }
+ };
+
+ function _connectFailure(xhr, message)
+ {
+ _debug('Connect failure');
+
+ // Notify listeners
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: '/meta/connect',
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'retry',
+ interval: _backoff
+ }
+ };
+ _notifyListeners('/meta/connect', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+
+ if (!_isDisconnected())
+ {
+ var action = _advice.reconnect ? _advice.reconnect : 'retry';
+ switch (action)
+ {
+ case 'retry':
+ _increaseBackoff();
+ _debug('Connect failure, backing off and retrying in {} ms', _backoff);
+ _delayedConnect();
+ break;
+ case 'handshake':
+ _resetBackoff();
+ _delayedHandshake();
+ break;
+ case 'none':
+ _resetBackoff();
+ break;
+ default:
+ _debug('Unrecognized reconnect value: {}', action);
+ break;
+ }
+ }
+ };
+
+ function _disconnectSuccess(message)
+ {
+ if (message.successful)
+ {
+ _debug('Disconnect successful');
+ _disconnect(false);
+ _notifyListeners('/meta/disconnect', message);
+ }
+ else
+ {
+ _debug('Disconnect unsuccessful');
+ _disconnect(true);
+ _notifyListeners('/meta/disconnect', message);
+ _notifyListeners('/meta/usuccessful', message);
+ }
+ };
+
+ function _disconnect(abort)
+ {
+ _cancelDelayedSend();
+ if (abort) _transport.abort();
+ _clientId = null;
+ _setStatus('disconnected');
+ _batch = 0;
+ _messageQueue = [];
+ _resetBackoff();
+ };
+
+ function _disconnectFailure(xhr, message)
+ {
+ _debug('Disconnect failure');
+ _disconnect(true);
+
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: '/meta/disconnect',
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'none',
+ interval: 0
+ }
+ };
+ _notifyListeners('/meta/disconnect', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+ };
+
+ function _subscribeSuccess(message)
+ {
+ if (message.successful)
+ {
+ _debug('Subscribe successful');
+ _notifyListeners('/meta/subscribe', message);
+ }
+ else
+ {
+ _debug('Subscribe unsuccessful');
+ _notifyListeners('/meta/subscribe', message);
+ _notifyListeners('/meta/unsuccessful', message);
+ }
+ };
+
+ function _subscribeFailure(xhr, message)
+ {
+ _debug('Subscribe failure');
+
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: '/meta/subscribe',
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'none',
+ interval: 0
+ }
+ };
+ _notifyListeners('/meta/subscribe', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+ };
+
+ function _unsubscribeSuccess(message)
+ {
+ if (message.successful)
+ {
+ _debug('Unsubscribe successful');
+ _notifyListeners('/meta/unsubscribe', message);
+ }
+ else
+ {
+ _debug('Unsubscribe unsuccessful');
+ _notifyListeners('/meta/unsubscribe', message);
+ _notifyListeners('/meta/unsuccessful', message);
+ }
+ };
+
+ function _unsubscribeFailure(xhr, message)
+ {
+ _debug('Unsubscribe failure');
+
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: '/meta/unsubscribe',
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'none',
+ interval: 0
+ }
+ };
+ _notifyListeners('/meta/unsubscribe', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+ };
+
+ function _messageSuccess(message)
+ {
+ if (message.successful === undefined)
+ {
+ if (message.data)
+ {
+ // It is a plain message, and not a bayeux meta message
+ _notifyListeners(message.channel, message);
+ }
+ else
+ {
+ _debug('Unknown message {}', JSON.stringify(message));
+ }
+ }
+ else
+ {
+ if (message.successful)
+ {
+ _debug('Publish successful');
+ _notifyListeners('/meta/publish', message);
+ }
+ else
+ {
+ _debug('Publish unsuccessful');
+ _notifyListeners('/meta/publish', message);
+ _notifyListeners('/meta/unsuccessful', message);
+ }
+ }
+ };
+
+ function _messageFailure(xhr, message)
+ {
+ _debug('Publish failure');
+
+ var failureMessage = {
+ successful: false,
+ failure: true,
+ channel: message.channel,
+ request: message,
+ xhr: xhr,
+ advice: {
+ action: 'none',
+ interval: 0
+ }
+ };
+ _notifyListeners('/meta/publish', failureMessage);
+ _notifyListeners('/meta/unsuccessful', failureMessage);
+ };
+
+ function _notifyListeners(channel, message)
+ {
+ // Notify direct listeners
+ _notify(channel, message);
+
+ // Notify the globbing listeners
+ var channelParts = channel.split("/");
+ var last = channelParts.length - 1;
+ for (var i = last; i > 0; --i)
+ {
+ var channelPart = channelParts.slice(0, i).join('/') + '/*';
+ // We don't want to notify /foo/* if the channel is /foo/bar/baz,
+ // so we stop at the first non recursive globbing
+ if (i == last) _notify(channelPart, message);
+ // Add the recursive globber and notify
+ channelPart += '*';
+ _notify(channelPart, message);
+ }
+ };
+
+ function _notify(channel, message)
+ {
+ var subscriptions = _listeners[channel];
+ if (subscriptions && subscriptions.length > 0)
+ {
+ for (var i = 0; i < subscriptions.length; ++i)
+ {
+ var subscription = subscriptions[i];
+ // Subscriptions may come and go, so the array may have 'holes'
+ if (subscription)
+ {
+ try
+ {
+ _debug('Notifying subscription: channel \'{}\', callback \'{}\'', channel, subscription.callback.name);
+ subscription.callback.call(subscription.scope, message);
+ }
+ catch (x)
+ {
+ // Ignore exceptions from callbacks
+ _warn('Exception during execution of callback \'{}\' on channel \'{}\' for message {}, exception: {}', subscription.callback.name, channel, JSON.stringify(message), x);
+ }
+ }
+ }
+ }
+ };
+
+ function _resetBackoff()
+ {
+ _backoff = 0;
+ };
+
+ function _increaseBackoff()
+ {
+ if (_backoff < _maxBackoff) _backoff += _backoffIncrement;
+ };
+
+ var _error = this._error = function(text, args)
+ {
+ _log('error', _format.apply(this, arguments));
+ };
+
+ var _warn = this._warn = function(text, args)
+ {
+ _log('warn', _format.apply(this, arguments));
+ };
+
+ var _info = this._info = function(text, args)
+ {
+ _log('info', _format.apply(this, arguments));
+ };
+
+ var _debug = this._debug = function(text, args)
+ {
+ _log('debug', _format.apply(this, arguments));
+ };
+
+ function _log(level, text)
+ {
+ var priority = _logPriorities[level];
+ var configPriority = _logPriorities[_logLevel];
+ if (!configPriority) configPriority = _logPriorities['info'];
+ if (priority >= configPriority)
+ {
+ if (window.console) window.console.log(text);
+ }
+ };
+
+ function _format(text)
+ {
+ var braces = /\{\}/g;
+ var result = '';
+ var start = 0;
+ var count = 0;
+ while (braces.test(text))
+ {
+ result += text.substr(start, braces.lastIndex - start - 2);
+ var arg = arguments[++count];
+ result += arg !== undefined ? arg : '{}';
+ start = braces.lastIndex;
+ }
+ result += text.substr(start, text.length - start);
+ return result;
+ };
+
+ function newLongPollingTransport()
+ {
+ return $.extend({}, new Transport('long-polling'), new LongPollingTransport());
+ };
+
+ function newCallbackPollingTransport()
+ {
+ return $.extend({}, new Transport('callback-polling'), new CallbackPollingTransport());
+ };
+
+ /**
+ * Base object with the common functionality for transports.
+ * The key responsibility is to allow at most 2 outstanding requests to the server,
+ * to avoid that requests are sent behind a long poll.
+ * To achieve this, we have one reserved request for the long poll, and all other
+ * requests are serialized one after the other.
+ */
+ var Transport = function(type)
+ {
+ var _maxRequests = 2;
+ var _requestIds = 0;
+ var _cometRequest = null;
+ var _requests = [];
+ var _packets = [];
+
+ this.getType = function()
+ {
+ return type;
+ };
+
+ this.send = function(packet, comet)
+ {
+ if (comet)
+ _cometSend(this, packet);
+ else
+ _send(this, packet);
+ };
+
+ function _cometSend(self, packet)
+ {
+ if (_cometRequest !== null) throw 'Concurrent comet requests not allowed, request ' + _cometRequest.id + ' not yet completed';
+
+ var requestId = ++_requestIds;
+ _debug('Beginning comet request {}', requestId);
+
+ var request = {id: requestId};
+ _debug('Delivering comet request {}', requestId);
+ self.deliver(packet, request);
+ _cometRequest = request;
+ };
+
+ function _send(self, packet)
+ {
+ var requestId = ++_requestIds;
+ _debug('Beginning request {}, {} other requests, {} queued requests', requestId, _requests.length, _packets.length);
+
+ var request = {id: requestId};
+ // Consider the comet request which should always be present
+ if (_requests.length < _maxRequests - 1)
+ {
+ _debug('Delivering request {}', requestId);
+ self.deliver(packet, request);
+ _requests.push(request);
+ }
+ else
+ {
+ _packets.push([packet, request]);
+ _debug('Queued request {}, {} queued requests', requestId, _packets.length);
+ }
+ };
+
+ this.complete = function(request, success, comet)
+ {
+ if (comet)
+ _cometComplete(request);
+ else
+ _complete(this, request, success);
+ };
+
+ function _cometComplete(request)
+ {
+ var requestId = request.id;
+ if (_cometRequest !== request) throw 'Comet request mismatch, completing request ' + requestId;
+
+ // Reset comet request
+ _cometRequest = null;
+ _debug('Ended comet request {}', requestId);
+ };
+
+ function _complete(self, request, success)
+ {
+ var requestId = request.id;
+ var index = $.inArray(request, _requests);
+ // The index can be negative the request has been aborted
+ if (index >= 0) _requests.splice(index, 1);
+ _debug('Ended request {}, {} other requests, {} queued requests', requestId, _requests.length, _packets.length);
+
+ if (_packets.length > 0)
+ {
+ var packet = _packets.shift();
+ if (success)
+ {
+ _debug('Dequeueing and sending request {}, {} queued requests', packet[1].id, _packets.length);
+ _send(self, packet[0]);
+ }
+ else
+ {
+ _debug('Dequeueing and failing request {}, {} queued requests', packet[1].id, _packets.length);
+ // Keep the semantic of calling response callbacks asynchronously after the request
+ setTimeout(function() { packet[0].onFailure(packet[1], 'error'); }, 0);
+ }
+ }
+ };
+
+ this.abort = function()
+ {
+ for (var i = 0; i < _requests.length; ++i)
+ {
+ var request = _requests[i];
+ _debug('Aborting request {}', request.id);
+ if (request.xhr) request.xhr.abort();
+ }
+ if (_cometRequest)
+ {
+ _debug('Aborting comet request {}', _cometRequest.id);
+ if (_cometRequest.xhr) _cometRequest.xhr.abort();
+ }
+ _cometRequest = null;
+ _requests = [];
+ _packets = [];
+ };
+ };
+
+ var LongPollingTransport = function()
+ {
+ this.deliver = function(packet, request)
+ {
+ request.xhr = $.ajax({
+ url: packet.url,
+ type: 'POST',
+ contentType: 'text/json;charset=UTF-8',
+ beforeSend: function(xhr)
+ {
+ xhr.setRequestHeader('Connection', 'Keep-Alive');
+ return true;
+ },
+ data: JSON.stringify(packet.messages),
+ success: function(response) { packet.onSuccess(request, response); },
+ error: function(xhr, reason, exception) { packet.onFailure(request, reason, exception); }
+ });
+ };
+ };
+
+ var CallbackPollingTransport = function()
+ {
+ var _maxLength = 2000;
+ this.deliver = function(packet, request)
+ {
+ // Microsoft Internet Explorer has a 2083 URL max length
+ // We must ensure that we stay within that length
+ var messages = JSON.stringify(packet.messages);
+ // Encode the messages because all brackets, quotes, commas, colons, etc
+ // present in the JSON will be URL encoded, taking many more characters
+ var urlLength = packet.url.length + encodeURI(messages).length;
+ _debug('URL length: {}', urlLength);
+ // Let's stay on the safe side and use 2000 instead of 2083
+ // also because we did not count few characters among which
+ // the parameter name 'message' and the parameter 'jsonp',
+ // which sum up to about 50 chars
+ if (urlLength > _maxLength)
+ {
+ var x = packet.messages.length > 1 ?
+ 'Too many bayeux messages in the same batch resulting in message too big ' +
+ '(' + urlLength + ' bytes, max is ' + _maxLength + ') for transport ' + this.getType() :
+ 'Bayeux message too big (' + urlLength + ' bytes, max is ' + _maxLength + ') ' +
+ 'for transport ' + this.getType();
+ // Keep the semantic of calling response callbacks asynchronously after the request
+ _setTimeout(function() { packet.onFailure(request, 'error', x); }, 0);
+ }
+ else
+ {
+ $.ajax({
+ url: packet.url,
+ type: 'GET',
+ dataType: 'jsonp',
+ jsonp: 'jsonp',
+ beforeSend: function(xhr)
+ {
+ xhr.setRequestHeader('Connection', 'Keep-Alive');
+ return true;
+ },
+ data:
+ {
+ // In callback-polling, the content must be sent via the 'message' parameter
+ message: messages
+ },
+ success: function(response) { packet.onSuccess(request, response); },
+ error: function(xhr, reason, exception) { packet.onFailure(request, reason, exception); }
+ });
+ }
+ };
+ };
+ };
+
+ /**
+ * The JS object that exposes the comet API to applications
+ */
+ $.cometd = new $.Cometd(); // The default instance
+
+})(jQuery);