/*
* Copyright (c) 2010 the original author or authors.
*
* 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.
*/
if (typeof dojo !== 'undefined')
{
dojo.provide('org.cometd');
}
else
{
// Namespaces for the cometd implementation
this.org = this.org || {};
org.cometd = {};
}
org.cometd.JSON = {};
org.cometd.JSON.toJSON = org.cometd.JSON.fromJSON = function(object)
{
throw 'Abstract';
};
org.cometd.Utils = {};
org.cometd.Utils.isString = function(value)
{
if (value === undefined || value === null)
{
return false;
}
return typeof value === 'string' || value instanceof String;
};
org.cometd.Utils.isArray = function(value)
{
if (value === undefined || value === null)
{
return false;
}
return value instanceof Array;
};
/**
* Returns whether the given element is contained into the given array.
* @param element the element to check presence for
* @param array the array to check for the element presence
* @return the index of the element, if present, or a negative index if the element is not present
*/
org.cometd.Utils.inArray = function(element, array)
{
for (var i = 0; i < array.length; ++i)
{
if (element == array[i])
{
return i;
}
}
return -1;
};
org.cometd.Utils.setTimeout = function(cometd, funktion, delay)
{
return setTimeout(function()
{
try
{
funktion();
}
catch (x)
{
cometd._debug('Exception invoking timed function', funktion, x);
}
}, delay);
};
/**
* A registry for transports used by the Cometd object.
*/
org.cometd.TransportRegistry = function()
{
var _types = [];
var _transports = {};
this.getTransportTypes = function()
{
return _types.slice(0);
};
this.findTransportTypes = function(version, crossDomain, url)
{
var result = [];
for (var i = 0; i < _types.length; ++i)
{
var type = _types[i];
if (_transports[type].accept(version, crossDomain, url) === true)
{
result.push(type);
}
}
return result;
};
this.negotiateTransport = function(types, version, crossDomain, url)
{
for (var i = 0; i < _types.length; ++i)
{
var type = _types[i];
for (var j = 0; j < types.length; ++j)
{
if (type == types[j])
{
var transport = _transports[type];
if (transport.accept(version, crossDomain, url) === true)
{
return transport;
}
}
}
}
return null;
};
this.add = function(type, transport, index)
{
var existing = false;
for (var i = 0; i < _types.length; ++i)
{
if (_types[i] == type)
{
existing = true;
break;
}
}
if (!existing)
{
if (typeof index !== 'number')
{
_types.push(type);
}
else
{
_types.splice(index, 0, type);
}
_transports[type] = transport;
}
return !existing;
};
this.find = function(type)
{
for (var i = 0; i < _types.length; ++i)
{
if (_types[i] == type)
{
return _transports[type];
}
}
return null;
};
this.remove = function(type)
{
for (var i = 0; i < _types.length; ++i)
{
if (_types[i] == type)
{
_types.splice(i, 1);
var transport = _transports[type];
delete _transports[type];
return transport;
}
}
return null;
};
this.reset = function()
{
for (var i = 0; i < _types.length; ++i)
{
_transports[_types[i]].reset();
}
};
};
/**
* Base object with the common functionality for transports.
*/
org.cometd.Transport = function()
{
var _type;
var _cometd;
/**
* Function invoked just after a transport has been successfully registered.
* @param type the type of transport (for example 'long-polling')
* @param cometd the cometd object this transport has been registered to
* @see #unregistered()
*/
this.registered = function(type, cometd)
{
_type = type;
_cometd = cometd;
};
/**
* Function invoked just after a transport has been successfully unregistered.
* @see #registered(type, cometd)
*/
this.unregistered = function()
{
_type = null;
_cometd = null;
};
this._debug = function()
{
_cometd._debug.apply(_cometd, arguments);
};
this._mixin = function()
{
return _cometd._mixin.apply(_cometd, arguments);
};
this.getConfiguration = function()
{
return _cometd.getConfiguration();
};
this.getAdvice = function()
{
return _cometd.getAdvice();
};
this.setTimeout = function(funktion, delay)
{
return org.cometd.Utils.setTimeout(_cometd, funktion, delay);
};
/**
* 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
*/
this.convertToMessages = function (response)
{
if (org.cometd.Utils.isString(response))
{
try
{
return org.cometd.JSON.fromJSON(response);
}
catch(x)
{
this._debug('Could not convert to JSON the following string', '"' + response + '"');
throw x;
}
}
if (org.cometd.Utils.isArray(response))
{
return response;
}
if (response === undefined || response === null)
{
return [];
}
if (response instanceof Object)
{
return [response];
}
throw 'Conversion Error ' + response + ', typeof ' + (typeof response);
};
/**
* Returns whether this transport can work for the given version and cross domain communication case.
* @param version a string indicating the transport version
* @param crossDomain a boolean indicating whether the communication is cross domain
* @return true if this transport can work for the given version and cross domain communication case,
* false otherwise
*/
this.accept = function(version, crossDomain, url)
{
throw 'Abstract';
};
/**
* Returns the type of this transport.
* @see #registered(type, cometd)
*/
this.getType = function()
{
return _type;
};
this.send = function(envelope, metaConnect)
{
throw 'Abstract';
};
this.reset = function()
{
this._debug('Transport', _type, 'reset');
};
this.abort = function()
{
this._debug('Transport', _type, 'aborted');
};
this.toString = function()
{
return this.getType();
};
};
org.cometd.Transport.derive = function(baseObject)
{
function F() {}
F.prototype = baseObject;
return new F();
};
/**
* Base object with the common functionality for transports based on requests.
* 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.
*/
org.cometd.RequestTransport = function()
{
var _super = new org.cometd.Transport();
var _self = org.cometd.Transport.derive(_super);
var _requestIds = 0;
var _metaConnectRequest = null;
var _requests = [];
var _envelopes = [];
function _coalesceEnvelopes(envelope)
{
while (_envelopes.length > 0)
{
var envelopeAndRequest = _envelopes[0];
var newEnvelope = envelopeAndRequest[0];
var newRequest = envelopeAndRequest[1];
if (newEnvelope.url === envelope.url &&
newEnvelope.sync === envelope.sync)
{
_envelopes.shift();
envelope.messages = envelope.messages.concat(newEnvelope.messages);
this._debug('Coalesced', newEnvelope.messages.length, 'messages from request', newRequest.id);
continue;
}
break;
}
}
function _transportSend(envelope, request)
{
this.transportSend(envelope, request);
request.expired = false;
if (!envelope.sync)
{
var maxDelay = this.getConfiguration().maxNetworkDelay;
var delay = maxDelay;
if (request.metaConnect === true)
{
delay += this.getAdvice().timeout;
}
this._debug('Transport', this.getType(), 'waiting at most', delay, 'ms for the response, maxNetworkDelay', maxDelay);
var self = this;
request.timeout = this.setTimeout(function()
{
request.expired = true;
if (request.xhr)
{
request.xhr.abort();
}
var errorMessage = 'Request ' + request.id + ' of transport ' + self.getType() + ' exceeded ' + delay + ' ms max network delay';
self._debug(errorMessage);
self.complete(request, false, request.metaConnect);
envelope.onFailure(request.xhr, envelope.messages, 'timeout', errorMessage);
}, delay);
}
}
function _queueSend(envelope)
{
var requestId = ++_requestIds;
var request = {
id: requestId,
metaConnect: false
};
// Consider the metaConnect requests which should always be present
if (_requests.length < this.getConfiguration().maxConnections - 1)
{
_requests.push(request);
_transportSend.call(this, envelope, request);
}
else
{
this._debug('Transport', this.getType(), 'queueing request', requestId, 'envelope', envelope);
_envelopes.push([envelope, request]);
}
}
function _metaConnectComplete(request)
{
var requestId = request.id;
this._debug('Transport', this.getType(), 'metaConnect complete, request', requestId);
if (_metaConnectRequest !== null && _metaConnectRequest.id !== requestId)
{
throw 'Longpoll request mismatch, completing request ' + requestId;
}
// Reset metaConnect request
_metaConnectRequest = null;
}
function _complete(request, success)
{
var index = org.cometd.Utils.inArray(request, _requests);
// The index can be negative if the request has been aborted
if (index >= 0)
{
_requests.splice(index, 1);
}
if (_envelopes.length > 0)
{
var envelopeAndRequest = _envelopes.shift();
var nextEnvelope = envelopeAndRequest[0];
var nextRequest = envelopeAndRequest[1];
this._debug('Transport dequeued request', nextRequest.id);
if (success)
{
if (this.getConfiguration().autoBatch)
{
_coalesceEnvelopes.call(this, nextEnvelope);
}
_queueSend.call(this, nextEnvelope);
this._debug('Transport completed request', request.id, nextEnvelope);
}
else
{
// Keep the semantic of calling response callbacks asynchronously after the request
var self = this;
this.setTimeout(function()
{
self.complete(nextRequest, false, nextRequest.metaConnect);
nextEnvelope.onFailure(nextRequest.xhr, nextEnvelope.messages, 'error', 'Previous request failed');
}, 0);
}
}
}
_self.complete = function(request, success, metaConnect)
{
if (metaConnect)
{
_metaConnectComplete.call(this, request);
}
else
{
_complete.call(this, request, success);
}
};
/**
* Performs the actual send depending on the transport type details.
* @param envelope the envelope to send
* @param request the request information
*/
_self.transportSend = function(envelope, request)
{
throw 'Abstract';
};
_self.transportSuccess = function(envelope, request, responses)
{
if (!request.expired)
{
clearTimeout(request.timeout);
this.complete(request, true, request.metaConnect);
if (responses && responses.length > 0)
{
envelope.onSuccess(responses);
}
else
{
envelope.onFailure(request.xhr, envelope.messages, 'Empty HTTP response');
}
}
};
_self.transportFailure = function(envelope, request, reason, exception)
{
if (!request.expired)
{
clearTimeout(request.timeout);
this.complete(request, false, request.metaConnect);
envelope.onFailure(request.xhr, envelope.messages, reason, exception);
}
};
function _metaConnectSend(envelope)
{
if (_metaConnectRequest !== null)
{
throw 'Concurrent metaConnect requests not allowed, request id=' + _metaConnectRequest.id + ' not yet completed';
}
var requestId = ++_requestIds;
this._debug('Transport', this.getType(), 'metaConnect send, request', requestId, 'envelope', envelope);
var request = {
id: requestId,
metaConnect: true
};
_transportSend.call(this, envelope, request);
_metaConnectRequest = request;
}
_self.send = function(envelope, metaConnect)
{
if (metaConnect)
{
_metaConnectSend.call(this, envelope);
}
else
{
_queueSend.call(this, envelope);
}
};
_self.abort = function()
{
_super.abort();
for (var i = 0; i < _requests.length; ++i)
{
var request = _requests[i];
this._debug('Aborting request', request);
if (request.xhr)
{
request.xhr.abort();
}
}
if (_metaConnectRequest)
{
this._debug('Aborting metaConnect request', _metaConnectRequest);
if (_metaConnectRequest.xhr)
{
_metaConnectRequest.xhr.abort();
}
}
this.reset();
};
_self.reset = function()
{
_super.reset();
_metaConnectRequest = null;
_requests = [];
_envelopes = [];
};
return _self;
};
org.cometd.LongPollingTransport = function()
{
var _super = new org.cometd.RequestTransport();
var _self = org.cometd.Transport.derive(_super);
// By default, support cross domain
var _supportsCrossDomain = true;
_self.accept = function(version, crossDomain, url)
{
return _supportsCrossDomain || !crossDomain;
};
_self.xhrSend = function(packet)
{
throw 'Abstract';
};
_self.transportSend = function(envelope, request)
{
this._debug('Transport', this.getType(), 'sending request', request.id, 'envelope', envelope);
var self = this;
try
{
var sameStack = true;
request.xhr = this.xhrSend({
transport: this,
url: envelope.url,
sync: envelope.sync,
headers: this.getConfiguration().requestHeaders,
body: org.cometd.JSON.toJSON(envelope.messages),
onSuccess: function(response)
{
self._debug('Transport', self.getType(), 'received response', response);
var success = false;
try
{
var received = self.convertToMessages(response);
if (received.length === 0)
{
_supportsCrossDomain = false;
self.transportFailure(envelope, request, 'no response', null);
}
else
{
success = true;
self.transportSuccess(envelope, request, received);
}
}
catch(x)
{
self._debug(x);
if (!success)
{
_supportsCrossDomain = false;
self.transportFailure(envelope, request, 'bad response', x);
}
}
},
onError: function(reason, exception)
{
_supportsCrossDomain = false;
if (sameStack)
{
// Keep the semantic of calling response callbacks asynchronously after the request
self.setTimeout(function()
{
self.transportFailure(envelope, request, reason, exception);
}, 0);
}
else
{
self.transportFailure(envelope, request, reason, exception);
}
}
});
sameStack = false;
}
catch (x)
{
_supportsCrossDomain = false;
// Keep the semantic of calling response callbacks asynchronously after the request
this.setTimeout(function()
{
self.transportFailure(envelope, request, 'error', x);
}, 0);
}
};
_self.reset = function()
{
_super.reset();
_supportsCrossDomain = true;
};
return _self;
};
org.cometd.CallbackPollingTransport = function()
{
var _super = new org.cometd.RequestTransport();
var _self = org.cometd.Transport.derive(_super);
var _maxLength = 2000;
_self.accept = function(version, crossDomain, url)
{
return true;
};
_self.jsonpSend = function(packet)
{
throw 'Abstract';
};
_self.transportSend = function(envelope, request)
{
var self = this;
// Microsoft Internet Explorer has a 2083 URL max length
// We must ensure that we stay within that length
var start = 0;
var length = envelope.messages.length;
var lengths = [];
while (length > 0)
{
// Encode the messages because all brackets, quotes, commas, colons, etc
// present in the JSON will be URL encoded, taking many more characters
var json = org.cometd.JSON.toJSON(envelope.messages.slice(start, start + length));
var urlLength = envelope.url.length + encodeURI(json).length;
// 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)
{
if (length == 1)
{
var x = 'Bayeux message too big (' + urlLength + ' bytes, max is ' + _maxLength + ') ' +
'for transport ' + this.getType();
// Keep the semantic of calling response callbacks asynchronously after the request
this.setTimeout(function()
{
self.transportFailure(envelope, request, 'error', x);
}, 0);
return;
}
--length;
continue;
}
lengths.push(length);
start += length;
length = envelope.messages.length - start;
}
// Here we are sure that the messages can be sent within the URL limit
var envelopeToSend = envelope;
if (lengths.length > 1)
{
var begin = 0;
var end = lengths[0];
this._debug('Transport', this.getType(), 'split', envelope.messages.length, 'messages into', lengths.join(' + '));
envelopeToSend = this._mixin(false, {}, envelope);
envelopeToSend.messages = envelope.messages.slice(begin, end);
envelopeToSend.onSuccess = envelope.onSuccess;
envelopeToSend.onFailure = envelope.onFailure;
for (var i = 1; i < lengths.length; ++i)
{
var nextEnvelope = this._mixin(false, {}, envelope);
begin = end;
end += lengths[i];
nextEnvelope.messages = envelope.messages.slice(begin, end);
nextEnvelope.onSuccess = envelope.onSuccess;
nextEnvelope.onFailure = envelope.onFailure;
this.send(nextEnvelope, request.metaConnect);
}
}
this._debug('Transport', this.getType(), 'sending request', request.id, 'envelope', envelopeToSend);
try
{
var sameStack = true;
this.jsonpSend({
transport: this,
url: envelopeToSend.url,
sync: envelopeToSend.sync,
headers: this.getConfiguration().requestHeaders,
body: org.cometd.JSON.toJSON(envelopeToSend.messages),
onSuccess: function(responses)
{
var success = false;
try
{
var received = self.convertToMessages(responses);
if (received.length === 0)
{
self.transportFailure(envelopeToSend, request, 'no response');
}
else
{
success=true;
self.transportSuccess(envelopeToSend, request, received);
}
}
catch (x)
{
self._debug(x);
if (!success)
{
self.transportFailure(envelopeToSend, request, 'bad response', x);
}
}
},
onError: function(reason, exception)
{
if (sameStack)
{
// Keep the semantic of calling response callbacks asynchronously after the request
self.setTimeout(function()
{
self.transportFailure(envelopeToSend, request, reason, exception);
}, 0);
}
else
{
self.transportFailure(envelopeToSend, request, reason, exception);
}
}
});
sameStack = false;
}
catch (xx)
{
// Keep the semantic of calling response callbacks asynchronously after the request
this.setTimeout(function()
{
self.transportFailure(envelopeToSend, request, 'error', xx);
}, 0);
}
};
return _self;
};
org.cometd.WebSocketTransport = function()
{
var OPENED = 1;
var CLOSED = 2;
var _super = new org.cometd.Transport();
var _self = org.cometd.Transport.derive(_super);
var _cometd;
// By default, support WebSocket
var _supportsWebSocket = true;
var _webSocketSupported = false;
var _state = CLOSED;
var _timeouts = {};
var _envelopes = {};
var _webSocket;
var _successCallback;
_self.registered = function(type, cometd)
{
_super.registered(type, cometd);
_cometd = cometd;
};
_self.accept = function(version, crossDomain, url)
{
// Using !! to return a boolean (and not the WebSocket object)
return _supportsWebSocket && !!window.WebSocket && _cometd.websocketEnabled === true;
};
function _websocketSend(envelope, metaConnect)
{
try
{
var json = org.cometd.JSON.toJSON(envelope.messages);
_webSocket.send(json);
this._debug('Transport', this.getType(), 'sent', envelope, 'metaConnect =', metaConnect);
// Manage the timeout waiting for the response
var maxDelay = this.getConfiguration().maxNetworkDelay;
var delay = maxDelay;
if (metaConnect)
{
delay += this.getAdvice().timeout;
}
var messageIds = [];
for (var i = 0; i < envelope.messages.length; ++i)
{
var message = envelope.messages[i];
if (message.id)
{
messageIds.push(message.id);
var self = this;
_timeouts[message.id] = this.setTimeout(function()
{
var errorMessage = 'Message ' + message.id + ' of transport ' + self.getType() + ' exceeded ' + delay + ' ms max network delay';
self._debug(errorMessage);
delete _timeouts[message.id];
for (var ids in _envelopes)
{
if (_envelopes[ids] === envelope)
{
delete _envelopes[ids];
break;
}
}
envelope.onFailure(_webSocket, envelope.messages, 'timeout', errorMessage);
}, delay);
}
}
this._debug('Transport', this.getType(), 'waiting at most', delay, ' ms for messages', messageIds, 'maxNetworkDelay', maxDelay, ', timeouts:', _timeouts);
}
catch (x)
{
// Keep the semantic of calling response callbacks asynchronously after the request
this.setTimeout(function()
{
envelope.onFailure(_webSocket, envelope.messages, 'error', x);
}, 0);
}
}
_self.onMessage = function(wsMessage)
{
this._debug('Transport', this.getType(), 'received websocket message', wsMessage);
if (_state === OPENED)
{
var messages = this.convertToMessages(wsMessage.data);
var messageIds = [];
for (var i = 0; i < messages.length; ++i)
{
var message = messages[i];
// Detect if the message is a response to a request we made.
// If it's a meta message, for sure it's a response;
// otherwise it's a publish message and publish responses lack the data field
if (/^\/meta\//.test(message.channel) || message.data === undefined)
{
if (message.id)
{
messageIds.push(message.id);
var timeout = _timeouts[message.id];
if (timeout)
{
clearTimeout(timeout);
delete _timeouts[message.id];
this._debug('Transport', this.getType(), 'removed timeout for message', message.id, ', timeouts', _timeouts);
}
}
}
if ('/meta/disconnect' === message.channel && message.successful)
{
_webSocket.close();
}
}
// Remove the envelope corresponding to the messages
var removed = false;
for (var j = 0; j < messageIds.length; ++j)
{
var id = messageIds[j];
for (var key in _envelopes)
{
var ids = key.split(',');
var index = org.cometd.Utils.inArray(id, ids);
if (index >= 0)
{
removed = true;
ids.splice(index, 1);
var envelope = _envelopes[key];
delete _envelopes[key];
if (ids.length > 0)
{
_envelopes[ids.join(',')] = envelope;
}
break;
}
}
}
if (removed)
{
this._debug('Transport', this.getType(), 'removed envelope, envelopes', _envelopes);
}
_successCallback.call(this, messages);
}
};
_self.onClose = function()
{
this._debug('Transport', this.getType(), 'closed', _webSocket);
// Remember if we were able to connect
// This close event could be due to server shutdown, and if it restarts we want to try websocket again
_supportsWebSocket = _webSocketSupported;
for (var id in _timeouts)
{
clearTimeout(_timeouts[id]);
delete _timeouts[id];
}
for (var ids in _envelopes)
{
_envelopes[ids].onFailure(_webSocket, _envelopes[ids].messages, 'closed');
delete _envelopes[ids];
}
_state = CLOSED;
};
_self.send = function(envelope, metaConnect)
{
this._debug('Transport', this.getType(), 'sending', envelope, 'metaConnect =', metaConnect);
// Store the envelope in any case; if the websocket cannot be opened, we fail it in close()
var messageIds = [];
for (var i = 0; i < envelope.messages.length; ++i)
{
var message = envelope.messages[i];
if (message.id)
{
messageIds.push(message.id);
}
}
_envelopes[messageIds.join(',')] = envelope;
this._debug('Transport', this.getType(), 'stored envelope, envelopes', _envelopes);
if (_state === OPENED)
{
_websocketSend.call(this, envelope, metaConnect);
}
else
{
// Mangle the URL, changing the scheme from 'http' to 'ws'
var url = envelope.url.replace(/^http/, 'ws');
this._debug('Transport', this.getType(), 'connecting to URL', url);
_webSocket = new window.WebSocket(url);
var self = this;
_webSocket.onopen = function()
{
self._debug('WebSocket opened', _webSocket);
_webSocketSupported = true;
_state = OPENED;
// Store the success callback, which is independent from the envelope,
// so that it can be used to notify arrival of messages.
_successCallback = envelope.onSuccess;
_websocketSend.call(self, envelope, metaConnect);
};
_webSocket.onclose = function()
{
self.onClose();
};
_webSocket.onmessage = function(message)
{
self.onMessage(message);
};
}
};
_self.reset = function()
{
_super.reset();
if (_webSocket)
{
_webSocket.close();
}
_supportsWebSocket = true;
_webSocketSupported = false;
_state = CLOSED;
_timeouts = {};
_envelopes = {};
_webSocket = null;
_successCallback = null;
};
return _self;
};
/**
* The constructor for a Cometd object, identified by an optional name.
* The default name is the string 'default'.
* In the rare case a page needs more than one Bayeux conversation,
* a new instance can be created via:
*
* var bayeuxUrl2 = ...;
*
* // Dojo style
* var cometd2 = new dojox.Cometd('another_optional_name');
*
* // jQuery style
* var cometd2 = new $.Cometd('another_optional_name');
*
* cometd2.init({url: bayeuxUrl2});
*
* @param name the optional name of this cometd object
*/
// IMPLEMENTATION NOTES:
// Be very careful in not changing the function order and pass this file every time through JSLint (http://jslint.com)
// The only implied globals must be "dojo", "org" and "window", and check that there are no "unused" warnings
// Failing to pass JSLint may result in shrinkers/minifiers to create an unusable file.
org.cometd.Cometd = function(name)
{
var _cometd = this;
var _name = name || 'default';
var _crossDomain = false;
var _transports = new org.cometd.TransportRegistry();
var _transport;
var _status = 'disconnected';
var _messageId = 0;
var _clientId = null;
var _batch = 0;
var _messageQueue = [];
var _internalBatch = false;
var _listeners = {};
var _backoff = 0;
var _scheduledSend = null;
var _extensions = [];
var _advice = {};
var _handshakeProps;
var _reestablish = false;
var _connected = false;
var _config = {
maxConnections: 2,
backoffIncrement: 1000,
maxBackoff: 60000,
logLevel: 'info',
reverseIncomingExtensions: true,
maxNetworkDelay: 10000,
requestHeaders: {},
appendMessageTypeToURL: true,
autoBatch: false,
advice: {
timeout: 60000,
interval: 0,
reconnect: 'retry'
}
};
/**
* Mixes in the given objects into the target object by copying the properties.
* @param deep if the copy must be deep
* @param target the target object
* @param objects the objects whose properties are copied into the target
*/
function _mixin(deep, target, objects)
{
var result = target || {};
// Skip first 2 parameters (deep and target), and loop over the others
for (var i = 2; i < arguments.length; ++i)
{
var object = arguments[i];
if (object === undefined || object === null)
{
continue;
}
for (var propName in object)
{
var prop = object[propName];
// Avoid infinite loops
if (prop === target)
{
continue;
}
// Do not mixin undefined values
if (prop === undefined)
{
continue;
}
if (deep && typeof prop === 'object' && prop !== null)
{
if (prop instanceof Array)
{
result[propName] = _mixin(deep, [], prop);
}
else
{
result[propName] = _mixin(deep, {}, prop);
}
}
else
{
result[propName] = prop;
}
}
}
return result;
}
/**
* This method is exposed as facility for extensions that may need to clone messages.
*/
this._mixin = _mixin;
function _isString(value)
{
return org.cometd.Utils.isString(value);
}
function _isFunction(value)
{
if (value === undefined || value === null)
{
return false;
}
return typeof value === 'function';
}
function _log(level, args)
{
if (window.console)
{
var logger = window.console[level];
if (_isFunction(logger))
{
logger.apply(window.console, args);
}
}
}
function _warn()
{
_log('warn', arguments);
}
this._warn = _warn;
function _info()
{
if (_config.logLevel != 'warn')
{
_log('info', arguments);
}
}
this._info = _info;
function _debug()
{
if (_config.logLevel == 'debug')
{
_log('debug', arguments);
}
}
this._debug = _debug;
function _configure(configuration)
{
_debug('Configuring cometd object with', configuration);
// Support old style param, where only the Bayeux server URL was passed
if (_isString(configuration))
{
configuration = { url: configuration };
}
if (!configuration)
{
configuration = {};
}
_config = _mixin(false, _config, configuration);
if (!_config.url)
{
throw 'Missing required configuration parameter \'url\' specifying the Bayeux server URL';
}
// Check if we're cross domain
// [1] = protocol:, [2] = //host:port, [3] = host:port, [4] = host, [5] = :port, [6] = port, [7] = uri, [8] = rest
var urlParts = /(^https?:)?(\/\/(([^:\/\?#]+)(:(\d+))?))?([^\?#]*)(.*)?/.exec(_config.url);
_crossDomain = urlParts[3] && urlParts[3] != window.location.host;
// Check if appending extra path is supported
if (_config.appendMessageTypeToURL)
{
if (urlParts[8] !== undefined && urlParts[8].length > 0)
{
_info('Appending message type to URI ' + urlParts[7] + urlParts[8] + ' is not supported, disabling \'appendMessageTypeToURL\' configuration');
_config.appendMessageTypeToURL = false;
}
else
{
var uriSegments = urlParts[7].split('/');
var lastSegmentIndex = uriSegments.length - 1;
if (urlParts[7].match(/\/$/))
{
lastSegmentIndex -= 1;
}
if (uriSegments[lastSegmentIndex].indexOf('.') >= 0)
{
// Very likely the CometD servlet's URL pattern is mapped to an extension, such as *.cometd
// It will be difficult to add the extra path in this case
_info('Appending message type to URI ' + urlParts[7] + ' is not supported, disabling \'appendMessageTypeToURL\' configuration');
_config.appendMessageTypeToURL = false;
}
}
}
}
function _clearSubscriptions()
{
for (var channel in _listeners)
{
var subscriptions = _listeners[channel];
for (var i = 0; i < subscriptions.length; ++i)
{
var subscription = subscriptions[i];
if (subscription && !subscription.listener)
{
delete subscriptions[i];
_debug('Removed subscription', subscription, 'for channel', channel);
}
}
}
}
function _setStatus(newStatus)
{
if (_status != newStatus)
{
_debug('Status', _status, '->', newStatus);
_status = newStatus;
}
}
function _isDisconnected()
{
return _status == 'disconnecting' || _status == 'disconnected';
}
function _nextMessageId()
{
return ++_messageId;
}
function _applyExtension(scope, callback, name, message, outgoing)
{
try
{
return callback.call(scope, message);
}
catch (x)
{
_debug('Exception during execution of extension', name, x);
var exceptionCallback = _cometd.onExtensionException;
if (_isFunction(exceptionCallback))
{
_debug('Invoking extension exception callback', name, x);
try
{
exceptionCallback.call(_cometd, x, name, outgoing, message);
}
catch(xx)
{
_info('Exception during execution of exception callback in extension', name, xx);
}
}
return message;
}
}
function _applyIncomingExtensions(message)
{
for (var i = 0; i < _extensions.length; ++i)
{
if (message === undefined || message === null)
{
break;
}
var index = _config.reverseIncomingExtensions ? _extensions.length - 1 - i : i;
var extension = _extensions[index];
var callback = extension.extension.incoming;
if (_isFunction(callback))
{
var result = _applyExtension(extension.extension, callback, extension.name, message, false);
message = result === undefined ? message : result;
}
}
return message;
}
function _applyOutgoingExtensions(message)
{
for (var i = 0; i < _extensions.length; ++i)
{
if (message === undefined || message === null)
{
break;
}
var extension = _extensions[i];
var callback = extension.extension.outgoing;
if (_isFunction(callback))
{
var result = _applyExtension(extension.extension, callback, extension.name, message, true);
message = result === undefined ? message : result;
}
}
return 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
{
subscription.callback.call(subscription.scope, message);
}
catch (x)
{
_debug('Exception during notification', subscription, message, x);
var listenerCallback = _cometd.onListenerException;
if (_isFunction(listenerCallback))
{
_debug('Invoking listener exception callback', subscription, x);
try
{
listenerCallback.call(_cometd, x, subscription.handle, subscription.listener, message);
}
catch (xx)
{
_info('Exception during execution of listener callback', subscription, xx);
}
}
}
}
}
}
}
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 _cancelDelayedSend()
{
if (_scheduledSend !== null)
{
clearTimeout(_scheduledSend);
}
_scheduledSend = null;
}
function _delayedSend(operation)
{
_cancelDelayedSend();
var delay = _advice.interval + _backoff;
_debug('Function scheduled in', delay, 'ms, interval =', _advice.interval, 'backoff =', _backoff, operation);
_scheduledSend = org.cometd.Utils.setTimeout(_cometd, operation, delay);
}
// Needed to break cyclic dependencies between function definitions
var _handleMessages;
var _handleFailure;
/**
* Delivers the messages to the CometD server
* @param messages the array of messages to send
* @param longpoll true if this send is a long poll
*/
function _send(sync, messages, longpoll, extraPath)
{
// 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.
for (var i = 0; i < messages.length; ++i)
{
var message = messages[i];
message.id = '' + _nextMessageId();
if (_clientId)
{
message.clientId = _clientId;
}
message = _applyOutgoingExtensions(message);
if (message !== undefined && message !== null)
{
messages[i] = message;
}
else
{
messages.splice(i--, 1);
}
}
if (messages.length === 0)
{
return;
}
var url = _config.url;
if (_config.appendMessageTypeToURL)
{
// If url does not end with '/', then append it
if (!url.match(/\/$/))
{
url = url + '/';
}
if (extraPath)
{
url = url + extraPath;
}
}
var envelope = {
url: url,
sync: sync,
messages: messages,
onSuccess: function(rcvdMessages)
{
try
{
_handleMessages.call(_cometd, rcvdMessages);
}
catch (x)
{
_debug('Exception during handling of messages', x);
}
},
onFailure: function(conduit, messages, reason, exception)
{
try
{
_handleFailure.call(_cometd, conduit, messages, reason, exception);
}
catch (x)
{
_debug('Exception during handling of failure', x);
}
}
};
_debug('Send', envelope);
_transport.send(envelope, longpoll);
}
function _queueSend(message)
{
if (_batch > 0 || _internalBatch === true)
{
_messageQueue.push(message);
}
else
{
_send(false, [message], false);
}
}
/**
* Sends a complete bayeux message.
* This method is exposed as a public so that extensions may use it
* to send bayeux message directly, for example in case of re-sending
* messages that have already been sent but that for some reason must
* be resent.
*/
this.send = _queueSend;
function _resetBackoff()
{
_backoff = 0;
}
function _increaseBackoff()
{
if (_backoff < _config.maxBackoff)
{
_backoff += _config.backoffIncrement;
}
}
/**
* Starts a the batch of messages to be sent in a single request.
* @see #_endBatch(sendMessages)
*/
function _startBatch()
{
++_batch;
}
function _flushBatch()
{
var messages = _messageQueue;
_messageQueue = [];
if (messages.length > 0)
{
_send(false, messages, false);
}
}
/**
* Ends the batch of messages to be sent in a single request,
* optionally sending messages present in the message queue depending
* on the given argument.
* @see #_startBatch()
*/
function _endBatch()
{
--_batch;
if (_batch < 0)
{
throw 'Calls to startBatch() and endBatch() are not paired';
}
if (_batch === 0 && !_isDisconnected() && !_internalBatch)
{
_flushBatch();
}
}
/**
* Sends the connect message
*/
function _connect()
{
if (!_isDisconnected())
{
var message = {
channel: '/meta/connect',
connectionType: _transport.getType()
};
// In case of reload or temporary loss of connection
// we want the next successful connect to return immediately
// instead of being held by the server, so that connect listeners
// can be notified that the connection has been re-established
if (!_connected)
{
message.advice = { timeout: 0 };
}
_setStatus('connecting');
_debug('Connect sent', message);
_send(false, [message], true, 'connect');
_setStatus('connected');
}
}
function _delayedConnect()
{
_setStatus('connecting');
_delayedSend(function()
{
_connect();
});
}
function _updateAdvice(newAdvice)
{
if (newAdvice)
{
_advice = _mixin(false, {}, _config.advice, newAdvice);
_debug('New advice', _advice);
}
}
function _disconnect(abort)
{
_cancelDelayedSend();
if (abort)
{
_transport.abort();
}
_clientId = null;
_setStatus('disconnected');
_batch = 0;
_resetBackoff();
// Fail any existing queued message
if (_messageQueue.length > 0)
{
_handleFailure.call(_cometd, undefined, _messageQueue, 'error', 'Disconnected');
_messageQueue = [];
}
}
/**
* Sends the initial handshake message
*/
function _handshake(handshakeProps)
{
_clientId = null;
_clearSubscriptions();
// Reset the transports if we're not retrying the handshake
if (_isDisconnected())
{
_transports.reset();
_updateAdvice(_config.advice);
}
else
{
// We are retrying the handshake, either because another handshake failed
// and we're backing off, or because the server timed us out and asks us to
// re-handshake: in both cases, make sure that if the handshake succeeds
// the next action is a connect.
_updateAdvice(_mixin(false, _advice, {reconnect: 'retry'}));
}
_batch = 0;
// Mark the start of an internal 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 temporarily any message until
// the connection is fully established.
_internalBatch = true;
// Save the properties provided by the user, so that
// we can reuse them during automatic re-handshake
_handshakeProps = handshakeProps;
var version = '1.0';
// Figure out the transports to send to the server
var transportTypes = _transports.findTransportTypes(version, _crossDomain, _config.url);
var bayeuxMessage = {
version: version,
minimumVersion: '0.9',
channel: '/meta/handshake',
supportedConnectionTypes: transportTypes,
advice: {
timeout: _advice.timeout,
interval: _advice.interval
}
};
// Do not allow the user to mess with the required properties,
// so merge first the user properties and *then* the bayeux message
var message = _mixin(false, {}, _handshakeProps, bayeuxMessage);
// Pick up the first available transport as initial transport
// since we don't know if the server supports it
_transport = _transports.negotiateTransport(transportTypes, version, _crossDomain, _config.url);
_debug('Initial transport is', _transport.getType());
// We started a batch to hold the application messages,
// so here we must bypass it and send immediately.
_setStatus('handshaking');
_debug('Handshake sent', message);
_send(false, [message], false, 'handshake');
}
function _delayedHandshake()
{
_setStatus('handshaking');
// We will call _handshake() which will reset _clientId, but we want to avoid
// that between the end of this method and the call to _handshake() someone may
// call publish() (or other methods that call _queueSend()).
_internalBatch = true;
_delayedSend(function()
{
_handshake(_handshakeProps);
});
}
function _failHandshake(message)
{
_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
var retry = !_isDisconnected() && _advice.reconnect != 'none';
if (retry)
{
_increaseBackoff();
_delayedHandshake();
}
else
{
_disconnect(false);
}
}
function _handshakeResponse(message)
{
if (message.successful)
{
// Save clientId, figure out transport, then follow the advice to connect
_clientId = message.clientId;
var newTransport = _transports.negotiateTransport(message.supportedConnectionTypes, message.version, _crossDomain, _config.url);
if (newTransport === null)
{
throw 'Could not negotiate transport with server; client ' +
_transports.findTransportTypes(message.version, _crossDomain, _config.url) +
', server ' + message.supportedConnectionTypes;
}
else if (_transport != newTransport)
{
_debug('Transport', _transport, '->', newTransport);
_transport = newTransport;
}
// End the internal batch and allow held messages from the application
// to go to the server (see _handshake() where we start the internal batch).
_internalBatch = false;
_flushBatch();
// Here the new transport is in place, as well as the clientId, so
// the listeners can perform a publish() if they want.
// Notify the listeners before the connect below.
message.reestablish = _reestablish;
_reestablish = true;
_notifyListeners('/meta/handshake', message);
var action = _isDisconnected() ? 'none' : _advice.reconnect;
switch (action)
{
case 'retry':
_resetBackoff();
_delayedConnect();
break;
case 'none':
_disconnect(false);
break;
default:
throw 'Unrecognized advice action ' + action;
}
}
else
{
_failHandshake(message);
}
}
function _handshakeFailure(xhr, message)
{
_failHandshake({
successful: false,
failure: true,
channel: '/meta/handshake',
request: message,
xhr: xhr,
advice: {
reconnect: 'retry',
interval: _backoff
}
});
}
function _failConnect(message)
{
// Notify the listeners after the status change but before the next action
_notifyListeners('/meta/connect', message);
_notifyListeners('/meta/unsuccessful', message);
// This may happen when the server crashed, the current clientId
// will be invalid, and the server will ask to handshake again
// Listeners can call disconnect(), so check the state after they run
var action = _isDisconnected() ? 'none' : _advice.reconnect;
switch (action)
{
case 'retry':
_increaseBackoff();
_delayedConnect();
break;
case 'handshake':
// The current transport may be failed (e.g. network disconnection)
// Reset the transports so the new handshake picks up the right one
_transports.reset();
_resetBackoff();
_delayedHandshake();
break;
case 'none':
_disconnect(false);
break;
default:
throw 'Unrecognized advice action' + action;
}
}
function _connectResponse(message)
{
_connected = message.successful;
if (_connected)
{
_notifyListeners('/meta/connect', message);
// 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)
// Listeners can call disconnect(), so check the state after they run
var action = _isDisconnected() ? 'none' : _advice.reconnect;
switch (action)
{
case 'retry':
_resetBackoff();
_delayedConnect();
break;
case 'none':
_disconnect(false);
break;
default:
throw 'Unrecognized advice action ' + action;
}
}
else
{
_failConnect(message);
}
}
function _connectFailure(xhr, message)
{
_connected = false;
_failConnect({
successful: false,
failure: true,
channel: '/meta/connect',
request: message,
xhr: xhr,
advice: {
reconnect: 'retry',
interval: _backoff
}
});
}
function _failDisconnect(message)
{
_disconnect(true);
_notifyListeners('/meta/disconnect', message);
_notifyListeners('/meta/unsuccessful', message);
}
function _disconnectResponse(message)
{
if (message.successful)
{
_disconnect(false);
_notifyListeners('/meta/disconnect', message);
}
else
{
_failDisconnect(message);
}
}
function _disconnectFailure(xhr, message)
{
_failDisconnect({
successful: false,
failure: true,
channel: '/meta/disconnect',
request: message,
xhr: xhr,
advice: {
reconnect: 'none',
interval: 0
}
});
}
function _failSubscribe(message)
{
_notifyListeners('/meta/subscribe', message);
_notifyListeners('/meta/unsuccessful', message);
}
function _subscribeResponse(message)
{
if (message.successful)
{
_notifyListeners('/meta/subscribe', message);
}
else
{
_failSubscribe(message);
}
}
function _subscribeFailure(xhr, message)
{
_failSubscribe({
successful: false,
failure: true,
channel: '/meta/subscribe',
request: message,
xhr: xhr,
advice: {
reconnect: 'none',
interval: 0
}
});
}
function _failUnsubscribe(message)
{
_notifyListeners('/meta/unsubscribe', message);
_notifyListeners('/meta/unsuccessful', message);
}
function _unsubscribeResponse(message)
{
if (message.successful)
{
_notifyListeners('/meta/unsubscribe', message);
}
else
{
_failUnsubscribe(message);
}
}
function _unsubscribeFailure(xhr, message)
{
_failUnsubscribe({
successful: false,
failure: true,
channel: '/meta/unsubscribe',
request: message,
xhr: xhr,
advice: {
reconnect: 'none',
interval: 0
}
});
}
function _failMessage(message)
{
_notifyListeners('/meta/publish', message);
_notifyListeners('/meta/unsuccessful', message);
}
function _messageResponse(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', message);
}
}
else
{
if (message.successful)
{
_notifyListeners('/meta/publish', message);
}
else
{
_failMessage(message);
}
}
}
function _messageFailure(xhr, message)
{
_failMessage({
successful: false,
failure: true,
channel: message.channel,
request: message,
xhr: xhr,
advice: {
reconnect: 'none',
interval: 0
}
});
}
function _receive(message)
{
message = _applyIncomingExtensions(message);
if (message === undefined || message === null)
{
return;
}
_updateAdvice(message.advice);
var channel = message.channel;
switch (channel)
{
case '/meta/handshake':
_handshakeResponse(message);
break;
case '/meta/connect':
_connectResponse(message);
break;
case '/meta/disconnect':
_disconnectResponse(message);
break;
case '/meta/subscribe':
_subscribeResponse(message);
break;
case '/meta/unsubscribe':
_unsubscribeResponse(message);
break;
default:
_messageResponse(message);
break;
}
}
/**
* Receives a message.
* This method is exposed as a public so that extensions may inject
* messages simulating that they had been received.
*/
this.receive = _receive;
_handleMessages = function _handleMessages(rcvdMessages)
{
_debug('Received', rcvdMessages);
for (var i = 0; i < rcvdMessages.length; ++i)
{
var message = rcvdMessages[i];
_receive(message);
}
};
_handleFailure = function _handleFailure(conduit, messages, reason, exception)
{
_debug('handleFailure', conduit, messages, reason, exception);
for (var i = 0; i < messages.length; ++i)
{
var message = messages[i];
var channel = message.channel;
switch (channel)
{
case '/meta/handshake':
_handshakeFailure(conduit, message);
break;
case '/meta/connect':
_connectFailure(conduit, message);
break;
case '/meta/disconnect':
_disconnectFailure(conduit, message);
break;
case '/meta/subscribe':
_subscribeFailure(conduit, message);
break;
case '/meta/unsubscribe':
_unsubscribeFailure(conduit, message);
break;
default:
_messageFailure(conduit, message);
break;
}
}
};
function _hasSubscriptions(channel)
{
var subscriptions = _listeners[channel];
if (subscriptions)
{
for (var i = 0; i < subscriptions.length; ++i)
{
if (subscriptions[i])
{
return true;
}
}
}
return false;
}
function _resolveScopedCallback(scope, callback)
{
var delegate = {
scope: scope,
method: callback
};
if (_isFunction(scope))
{
delegate.scope = undefined;
delegate.method = scope;
}
else
{
if (_isString(callback))
{
if (!scope)
{
throw 'Invalid scope ' + scope;
}
delegate.method = scope[callback];
if (!_isFunction(delegate.method))
{
throw 'Invalid callback ' + callback + ' for scope ' + scope;
}
}
else if (!_isFunction(callback))
{
throw 'Invalid callback ' + callback;
}
}
return delegate;
}
function _addListener(channel, scope, callback, isListener)
{
// The data structure is a map, where each subscription
// holds the callback to be called and its scope.
var delegate = _resolveScopedCallback(scope, callback);
_debug('Adding listener on', channel, 'with scope', delegate.scope, 'and callback', delegate.method);
var subscription = {
channel: channel,
scope: delegate.scope,
callback: delegate.method,
listener: isListener
};
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 subscriptionID = subscriptions.push(subscription) - 1;
subscription.id = subscriptionID;
subscription.handle = [channel, subscriptionID];
_debug('Added listener', subscription, 'for channel', channel, 'having id =', subscriptionID);
// The subscription to allow removal of the listener is made of the channel and the index
return subscription.handle;
}
function _removeListener(subscription)
{
var subscriptions = _listeners[subscription[0]];
if (subscriptions)
{
delete subscriptions[subscription[1]];
_debug('Removed listener', subscription);
}
}
//
// PUBLIC API
//
/**
* Registers the given transport under the given transport type.
* The optional index parameter specifies the "priority" at which the
* transport is registered (where 0 is the max priority).
* If a transport with the same type is already registered, this function
* does nothing and returns false.
* @param type the transport type
* @param transport the transport object
* @param index the index at which this transport is to be registered
* @return true if the transport has been registered, false otherwise
* @see #unregisterTransport(type)
*/
this.registerTransport = function(type, transport, index)
{
var result = _transports.add(type, transport, index);
if (result)
{
_debug('Registered transport', type);
if (_isFunction(transport.registered))
{
transport.registered(type, this);
}
}
return result;
};
/**
* @return an array of all registered transport types
*/
this.getTransportTypes = function()
{
return _transports.getTransportTypes();
};
/**
* Unregisters the transport with the given transport type.
* @param type the transport type to unregister
* @return the transport that has been unregistered,
* or null if no transport was previously registered under the given transport type
*/
this.unregisterTransport = function(type)
{
var transport = _transports.remove(type);
if (transport !== null)
{
_debug('Unregistered transport', type);
if (_isFunction(transport.unregistered))
{
transport.unregistered();
}
}
return transport;
};
this.findTransport = function(name)
{
return _transports.find(name);
};
/**
* Configures the initial Bayeux communication with the Bayeux server.
* Configuration is passed via an object that must contain a mandatory field url
* of type string containing the URL of the Bayeux server.
* @param configuration the configuration object
*/
this.configure = function(configuration)
{
_configure.call(this, configuration);
};
/**
* Configures and establishes the Bayeux communication with the Bayeux server
* via a handshake and a subsequent connect.
* @param configuration the configuration object
* @param handshakeProps an object to be merged with the handshake message
* @see #configure(configuration)
* @see #handshake(handshakeProps)
*/
this.init = function(configuration, handshakeProps)
{
this.configure(configuration);
this.handshake(handshakeProps);
};
/**
* Establishes the Bayeux communication with the Bayeux server
* via a handshake and a subsequent connect.
* @param handshakeProps an object to be merged with the handshake message
*/
this.handshake = function(handshakeProps)
{
_setStatus('disconnected');
_reestablish = false;
_handshake(handshakeProps);
};
/**
* Disconnects from the Bayeux server.
* It is possible to suggest to attempt a synchronous disconnect, but this feature
* may only be available in certain transports (for example, long-polling may support
* it, callback-polling certainly does not).
* @param sync whether attempt to perform a synchronous disconnect
* @param disconnectProps an object to be merged with the disconnect message
*/
this.disconnect = function(sync, disconnectProps)
{
if (_isDisconnected())
{
return;
}
if (disconnectProps === undefined)
{
if (typeof sync !== 'boolean')
{
disconnectProps = sync;
sync = false;
}
}
var bayeuxMessage = {
channel: '/meta/disconnect'
};
var message = _mixin(false, {}, disconnectProps, bayeuxMessage);
_setStatus('disconnecting');
_send(sync === true, [message], false, 'disconnect');
};
/**
* 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();
};
/**
* Executes the given callback in the given scope, surrounded by a {@link #startBatch()}
* and {@link #endBatch()} calls.
* @param scope the scope of the callback, may be omitted
* @param callback the callback to be executed within {@link #startBatch()} and {@link #endBatch()} calls
*/
this.batch = function(scope, callback)
{
var delegate = _resolveScopedCallback(scope, callback);
this.startBatch();
try
{
delegate.method.call(delegate.scope);
this.endBatch();
}
catch (x)
{
_debug('Exception during execution of batch', x);
this.endBatch();
throw x;
}
};
/**
* 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, may be omitted
* @param callback the callback to call when a message is sent to the channel
* @returns the subscription handle to be passed to {@link #removeListener(object)}
* @see #removeListener(subscription)
*/
this.addListener = function(channel, scope, callback)
{
if (arguments.length < 2)
{
throw 'Illegal arguments number: required 2, got ' + arguments.length;
}
if (!_isString(channel))
{
throw 'Illegal argument type: channel must be a string';
}
return _addListener(channel, scope, callback, true);
};
/**
* Removes the subscription obtained with a call to {@link #addListener(string, object, function)}.
* @param subscription the subscription to unsubscribe.
* @see #addListener(channel, scope, callback)
*/
this.removeListener = function(subscription)
{
if (!org.cometd.Utils.isArray(subscription))
{
throw 'Invalid argument: expected subscription, not ' + subscription;
}
_removeListener(subscription);
};
/**
* Removes all listeners registered with {@link #addListener(channel, scope, callback)} or
* {@link #subscribe(channel, scope, callback)}.
*/
this.clearListeners = function()
{
_listeners = {};
};
/**
* 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, may be omitted
* @param callback the callback to call when a message is sent 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)
{
if (arguments.length < 2)
{
throw 'Illegal arguments number: required 2, got ' + arguments.length;
}
if (!_isString(channel))
{
throw 'Illegal argument type: channel must be a string';
}
if (_isDisconnected())
{
throw 'Illegal state: already disconnected';
}
// Normalize arguments
if (_isFunction(scope))
{
subscribeProps = callback;
callback = scope;
scope = undefined;
}
// Only send the message to the server if this clientId has not yet subscribed to the channel
var send = !_hasSubscriptions(channel);
var subscription = _addListener(channel, scope, callback, false);
if (send)
{
// Send the subscription message after the subscription registration to avoid
// races where the server would send 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 = _mixin(false, {}, subscribeProps, bayeuxMessage);
_queueSend(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)
{
if (arguments.length < 1)
{
throw 'Illegal arguments number: required 1, got ' + arguments.length;
}
if (_isDisconnected())
{
throw 'Illegal state: already disconnected';
}
// 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 channel = subscription[0];
// Only send the message to the server if this clientId unsubscribes the last subscription
if (!_hasSubscriptions(channel))
{
var bayeuxMessage = {
channel: '/meta/unsubscribe',
subscription: channel
};
var message = _mixin(false, {}, unsubscribeProps, bayeuxMessage);
_queueSend(message);
}
};
/**
* Removes all subscriptions added via {@link #subscribe(channel, scope, callback, subscribeProps)},
* but does not remove the listeners added via {@link addListener(channel, scope, callback)}.
*/
this.clearSubscriptions = function()
{
_clearSubscriptions();
};
/**
* 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)
{
if (arguments.length < 1)
{
throw 'Illegal arguments number: required 1, got ' + arguments.length;
}
if (!_isString(channel))
{
throw 'Illegal argument type: channel must be a string';
}
if (_isDisconnected())
{
throw 'Illegal state: already disconnected';
}
var bayeuxMessage = {
channel: channel,
data: content
};
var message = _mixin(false, {}, publishProps, bayeuxMessage);
_queueSend(message);
};
/**
* Returns a string representing the status of the bayeux communication with the Bayeux server.
*/
this.getStatus = function()
{
return _status;
};
/**
* Returns whether this instance has been disconnected.
*/
this.isDisconnected = _isDisconnected;
/**
* 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)
{
_config.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 _config.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)
{
_config.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:
*
* {
* 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.
* @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)
{
if (arguments.length < 2)
{
throw 'Illegal arguments number: required 2, got ' + arguments.length;
}
if (!_isString(name))
{
throw 'Illegal argument type: extension name must be a string';
}
var existing = false;
for (var i = 0; i < _extensions.length; ++i)
{
var existingExtension = _extensions[i];
if (existingExtension.name == name)
{
existing = true;
break;
}
}
if (!existing)
{
_extensions.push({
name: name,
extension: extension
});
_debug('Registered extension', name);
// Callback for extensions
if (_isFunction(extension.registered))
{
extension.registered(name, this);
}
return true;
}
else
{
_info('Could not register extension with name', name, 'since 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)
{
if (!_isString(name))
{
throw 'Illegal argument type: extension name must be a string';
}
var unregistered = false;
for (var i = 0; i < _extensions.length; ++i)
{
var extension = _extensions[i];
if (extension.name == name)
{
_extensions.splice(i, 1);
unregistered = true;
_debug('Unregistered extension', name);
// Callback for extensions
var ext = extension.extension;
if (_isFunction(ext.unregistered))
{
ext.unregistered();
}
break;
}
}
return unregistered;
};
/**
* Find the extension registered with the given name.
* @param name the name of the extension to find
* @return the extension found or null if no extension with the given name has been registered
*/
this.getExtension = function(name)
{
for (var i = 0; i < _extensions.length; ++i)
{
var extension = _extensions[i];
if (extension.name == name)
{
return extension.extension;
}
}
return null;
};
/**
* Returns the name assigned to this Cometd object, or the string 'default'
* if no name has been explicitly passed as parameter to the constructor.
*/
this.getName = function()
{
return _name;
};
/**
* Returns the clientId assigned by the Bayeux server during handshake.
*/
this.getClientId = function()
{
return _clientId;
};
/**
* Returns the URL of the Bayeux server.
*/
this.getURL = function()
{
return _config.url;
};
this.getTransport = function()
{
return _transport;
};
this.getConfiguration = function()
{
return _mixin(true, {}, _config);
};
this.getAdvice = function()
{
return _mixin(true, {}, _advice);
};
};