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Diffstat (limited to 'contexts/data/lib/closure-library/closure/goog/net/xpc/iframepollingtransport.js')
| -rw-r--r-- | contexts/data/lib/closure-library/closure/goog/net/xpc/iframepollingtransport.js | 907 |
1 files changed, 0 insertions, 907 deletions
diff --git a/contexts/data/lib/closure-library/closure/goog/net/xpc/iframepollingtransport.js b/contexts/data/lib/closure-library/closure/goog/net/xpc/iframepollingtransport.js deleted file mode 100644 index 9f52c44..0000000 --- a/contexts/data/lib/closure-library/closure/goog/net/xpc/iframepollingtransport.js +++ /dev/null @@ -1,907 +0,0 @@ -// Copyright 2007 The Closure Library Authors. All Rights Reserved. -// -// 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. - -/** - * @fileoverview Contains the iframe polling transport. - */ - - -goog.provide('goog.net.xpc.IframePollingTransport'); -goog.provide('goog.net.xpc.IframePollingTransport.Receiver'); -goog.provide('goog.net.xpc.IframePollingTransport.Sender'); - -goog.require('goog.array'); -goog.require('goog.dom'); -goog.require('goog.net.xpc'); -goog.require('goog.net.xpc.CrossPageChannelRole'); -goog.require('goog.net.xpc.Transport'); -goog.require('goog.userAgent'); - - - -/** - * Iframe polling transport. Uses hidden iframes to transfer data - * in the fragment identifier of the URL. The peer polls the iframe's location - * for changes. - * Unfortunately, in Safari this screws up the history, because Safari doesn't - * allow to call location.replace() on a window containing a document from a - * different domain (last version tested: 2.0.4). - * - * @param {goog.net.xpc.CrossPageChannel} channel The channel this - * transport belongs to. - * @param {goog.dom.DomHelper=} opt_domHelper The dom helper to use for finding - * the correct window. - * @constructor - * @extends {goog.net.xpc.Transport} - */ -goog.net.xpc.IframePollingTransport = function(channel, opt_domHelper) { - goog.base(this, opt_domHelper); - - /** - * The channel this transport belongs to. - * @type {goog.net.xpc.CrossPageChannel} - * @private - */ - this.channel_ = channel; - - /** - * The URI used to send messages. - * @type {string} - * @private - */ - this.sendUri_ = - this.channel_.getConfig()[goog.net.xpc.CfgFields.PEER_POLL_URI]; - - /** - * The URI which is polled for incoming messages. - * @type {string} - * @private - */ - this.rcvUri_ = - this.channel_.getConfig()[goog.net.xpc.CfgFields.LOCAL_POLL_URI]; - - /** - * The queue to hold messages which can't be sent immediately. - * @type {Array} - * @private - */ - this.sendQueue_ = []; -}; -goog.inherits(goog.net.xpc.IframePollingTransport, goog.net.xpc.Transport); - - -/** - * The number of times the inner frame will check for evidence of the outer - * frame before it tries its reconnection sequence. These occur at 100ms - * intervals, making this an effective max waiting period of 500ms. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.pollsBeforeReconnect_ = 5; - - -/** - * The transport type. - * @type {number} - * @protected - * @override - */ -goog.net.xpc.IframePollingTransport.prototype.transportType = - goog.net.xpc.TransportTypes.IFRAME_POLLING; - - -/** - * Sequence counter. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.sequence_ = 0; - - -/** - * Flag indicating whether we are waiting for an acknoledgement. - * @type {boolean} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.waitForAck_ = false; - - -/** - * Flag indicating if channel has been initialized. - * @type {boolean} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.initialized_ = false; - - -/** - * Reconnection iframe created by inner peer. - * @type {Element} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.reconnectFrame_ = null; - - -/** - * The string used to prefix all iframe names and IDs. - * @type {string} - */ -goog.net.xpc.IframePollingTransport.IFRAME_PREFIX = 'googlexpc'; - - -/** - * Returns the name/ID of the message frame. - * @return {string} Name of message frame. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.getMsgFrameName_ = function() { - return goog.net.xpc.IframePollingTransport.IFRAME_PREFIX + '_' + - this.channel_.name + '_msg'; -}; - - -/** - * Returns the name/ID of the ack frame. - * @return {string} Name of ack frame. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.getAckFrameName_ = function() { - return goog.net.xpc.IframePollingTransport.IFRAME_PREFIX + '_' + - this.channel_.name + '_ack'; -}; - - -/** - * Determines whether the channel is still available. The channel is - * unavailable if the transport was disposed or the peer is no longer - * available. - * @return {boolean} Whether the channel is available. - */ -goog.net.xpc.IframePollingTransport.prototype.isChannelAvailable = function() { - return !this.isDisposed() && this.channel_.isPeerAvailable(); -}; - - -/** - * Safely retrieves the frames from the peer window. If an error is thrown - * (e.g. the window is closing) an empty frame object is returned. - * @return {!Object.<!Window>} The frames from the peer window. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.getPeerFrames_ = function() { - try { - if (this.isChannelAvailable()) { - return this.channel_.getPeerWindowObject().frames || {}; - } - } catch (e) { - // An error may be thrown if the window is closing. - goog.net.xpc.logger.fine('error retrieving peer frames'); - } - return {}; -}; - - -/** - * Safely retrieves the peer frame with the specified name. - * @param {string} frameName The name of the peer frame to retrieve. - * @return {Window} The peer frame with the specified name. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.getPeerFrame_ = function( - frameName) { - return this.getPeerFrames_()[frameName]; -}; - - -/** - * Connects this transport. - * @override - */ -goog.net.xpc.IframePollingTransport.prototype.connect = function() { - if (!this.isChannelAvailable()) { - // When the channel is unavailable there is no peer to poll so stop trying - // to connect. - return; - } - - goog.net.xpc.logger.fine('transport connect called'); - if (!this.initialized_) { - goog.net.xpc.logger.fine('initializing...'); - this.constructSenderFrames_(); - this.initialized_ = true; - } - this.checkForeignFramesReady_(); -}; - - -/** - * Creates the iframes which are used to send messages (and acknowledgements) - * to the peer. Sender iframes contain a document from a different origin and - * therefore their content can't be accessed. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.constructSenderFrames_ = - function() { - var name = this.getMsgFrameName_(); - this.msgIframeElm_ = this.constructSenderFrame_(name); - this.msgWinObj_ = this.getWindow().frames[name]; - - name = this.getAckFrameName_(); - this.ackIframeElm_ = this.constructSenderFrame_(name); - this.ackWinObj_ = this.getWindow().frames[name]; -}; - - -/** - * Constructs a sending frame the the given id. - * @param {string} id The id. - * @return {Element} The constructed frame. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.constructSenderFrame_ = - function(id) { - goog.net.xpc.logger.finest('constructing sender frame: ' + id); - var ifr = goog.dom.createElement('iframe'); - var s = ifr.style; - s.position = 'absolute'; - s.top = '-10px'; s.left = '10px'; s.width = '1px'; s.height = '1px'; - ifr.id = ifr.name = id; - ifr.src = this.sendUri_ + '#INITIAL'; - this.getWindow().document.body.appendChild(ifr); - return ifr; -}; - - -/** - * The protocol for reconnecting is for the inner frame to change channel - * names, and then communicate the new channel name to the outer peer. - * The outer peer looks in a predefined location for the channel name - * upate. It is important to use a completely new channel name, as this - * will ensure that all messaging iframes are not in the bfcache. - * Otherwise, Safari may pollute the history when modifying the location - * of bfcached iframes. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.maybeInnerPeerReconnect_ = - function() { - // Reconnection has been found to not function on some browsers (eg IE7), so - // it's important that the mechanism only be triggered as a last resort. As - // such, we poll a number of times to find the outer iframe before triggering - // it. - if (this.reconnectFrame_ || this.pollsBeforeReconnect_-- > 0) { - return; - } - - goog.net.xpc.logger.finest('Inner peer reconnect triggered.'); - this.channel_.name = goog.net.xpc.getRandomString(10); - goog.net.xpc.logger.finest('switching channels: ' + this.channel_.name); - this.deconstructSenderFrames_(); - this.initialized_ = false; - // Communicate new channel name to outer peer. - this.reconnectFrame_ = this.constructSenderFrame_( - goog.net.xpc.IframePollingTransport.IFRAME_PREFIX + - '_reconnect_' + this.channel_.name); -}; - - -/** - * Scans inner peer for a reconnect message, which will be used to update - * the outer peer's channel name. If a reconnect message is found, the - * sender frames will be cleaned up to make way for the new sender frames. - * Only called by the outer peer. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.outerPeerReconnect_ = function() { - goog.net.xpc.logger.finest('outerPeerReconnect called'); - var frames = this.getPeerFrames_(); - var length = frames.length; - for (var i = 0; i < length; i++) { - var frameName; - try { - if (frames[i] && frames[i].name) { - frameName = frames[i].name; - } - } catch (e) { - // Do nothing. - } - if (!frameName) { - continue; - } - var message = frameName.split('_'); - if (message.length == 3 && - message[0] == goog.net.xpc.IframePollingTransport.IFRAME_PREFIX && - message[1] == 'reconnect') { - // This is a legitimate reconnect message from the peer. Start using - // the peer provided channel name, and start a connection over from - // scratch. - this.channel_.name = message[2]; - this.deconstructSenderFrames_(); - this.initialized_ = false; - break; - } - } -}; - - -/** - * Cleans up the existing sender frames owned by this peer. Only called by - * the outer peer. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.deconstructSenderFrames_ = - function() { - goog.net.xpc.logger.finest('deconstructSenderFrames called'); - if (this.msgIframeElm_) { - this.msgIframeElm_.parentNode.removeChild(this.msgIframeElm_); - this.msgIframeElm_ = null; - this.msgWinObj_ = null; - } - if (this.ackIframeElm_) { - this.ackIframeElm_.parentNode.removeChild(this.ackIframeElm_); - this.ackIframeElm_ = null; - this.ackWinObj_ = null; - } -}; - - -/** - * Checks if the frames in the peer's page are ready. These contain a - * document from the own domain and are the ones messages are received through. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.checkForeignFramesReady_ = - function() { - // check if the connected iframe ready - if (!(this.isRcvFrameReady_(this.getMsgFrameName_()) && - this.isRcvFrameReady_(this.getAckFrameName_()))) { - goog.net.xpc.logger.finest('foreign frames not (yet) present'); - - if (this.channel_.getRole() == goog.net.xpc.CrossPageChannelRole.INNER) { - // The outer peer might need a short time to get its frames ready, as - // CrossPageChannel prevents them from getting created until the inner - // peer's frame has thrown its loaded event. This method is a noop for - // the first few times it's called, and then allows the reconnection - // sequence to begin. - this.maybeInnerPeerReconnect_(); - } else if (this.channel_.getRole() == - goog.net.xpc.CrossPageChannelRole.OUTER) { - // The inner peer is either not loaded yet, or the receiving - // frames are simply missing. Since we cannot discern the two cases, we - // should scan for a reconnect message from the inner peer. - this.outerPeerReconnect_(); - } - - // start a timer to check again - this.getWindow().setTimeout(goog.bind(this.connect, this), 100); - } else { - goog.net.xpc.logger.fine('foreign frames present'); - - // Create receivers. - this.msgReceiver_ = new goog.net.xpc.IframePollingTransport.Receiver( - this, - this.getPeerFrame_(this.getMsgFrameName_()), - goog.bind(this.processIncomingMsg, this)); - this.ackReceiver_ = new goog.net.xpc.IframePollingTransport.Receiver( - this, - this.getPeerFrame_(this.getAckFrameName_()), - goog.bind(this.processIncomingAck, this)); - - this.checkLocalFramesPresent_(); - } -}; - - -/** - * Checks if the receiving frame is ready. - * @param {string} frameName Which receiving frame to check. - * @return {boolean} Whether the receiving frame is ready. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.isRcvFrameReady_ = - function(frameName) { - goog.net.xpc.logger.finest('checking for receive frame: ' + frameName); - /** @preserveTry */ - try { - var winObj = this.getPeerFrame_(frameName); - if (!winObj || winObj.location.href.indexOf(this.rcvUri_) != 0) { - return false; - } - } catch (e) { - return false; - } - return true; -}; - - -/** - * Checks if the iframes created in the own document are ready. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.checkLocalFramesPresent_ = - function() { - - // Are the sender frames ready? - // These contain a document from the peer's domain, therefore we can only - // check if the frame itself is present. - var frames = this.getPeerFrames_(); - if (!(frames[this.getAckFrameName_()] && - frames[this.getMsgFrameName_()])) { - // start a timer to check again - if (!this.checkLocalFramesPresentCb_) { - this.checkLocalFramesPresentCb_ = goog.bind( - this.checkLocalFramesPresent_, this); - } - this.getWindow().setTimeout(this.checkLocalFramesPresentCb_, 100); - goog.net.xpc.logger.fine('local frames not (yet) present'); - } else { - // Create senders. - this.msgSender_ = new goog.net.xpc.IframePollingTransport.Sender( - this.sendUri_, this.msgWinObj_); - this.ackSender_ = new goog.net.xpc.IframePollingTransport.Sender( - this.sendUri_, this.ackWinObj_); - - goog.net.xpc.logger.fine('local frames ready'); - - this.getWindow().setTimeout(goog.bind(function() { - this.msgSender_.send(goog.net.xpc.SETUP); - this.sentConnectionSetup_ = true; - this.waitForAck_ = true; - goog.net.xpc.logger.fine('SETUP sent'); - }, this), 100); - } -}; - - -/** - * Check if connection is ready. - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.checkIfConnected_ = function() { - if (this.sentConnectionSetupAck_ && this.rcvdConnectionSetupAck_) { - this.channel_.notifyConnected(); - - if (this.deliveryQueue_) { - goog.net.xpc.logger.fine('delivering queued messages ' + - '(' + this.deliveryQueue_.length + ')'); - - for (var i = 0, m; i < this.deliveryQueue_.length; i++) { - m = this.deliveryQueue_[i]; - this.channel_.xpcDeliver(m.service, m.payload); - } - delete this.deliveryQueue_; - } - } else { - goog.net.xpc.logger.finest('checking if connected: ' + - 'ack sent:' + this.sentConnectionSetupAck_ + - ', ack rcvd: ' + this.rcvdConnectionSetupAck_); - } -}; - - -/** - * Processes an incoming message. - * @param {string} raw The complete received string. - */ -goog.net.xpc.IframePollingTransport.prototype.processIncomingMsg = - function(raw) { - goog.net.xpc.logger.finest('msg received: ' + raw); - - if (raw == goog.net.xpc.SETUP) { - if (!this.ackSender_) { - // Got SETUP msg, but we can't send an ack. - return; - } - - this.ackSender_.send(goog.net.xpc.SETUP_ACK_); - goog.net.xpc.logger.finest('SETUP_ACK sent'); - - this.sentConnectionSetupAck_ = true; - this.checkIfConnected_(); - - } else if (this.channel_.isConnected() || this.sentConnectionSetupAck_) { - - var pos = raw.indexOf('|'); - var head = raw.substring(0, pos); - var frame = raw.substring(pos + 1); - - // check if it is a framed message - pos = head.indexOf(','); - if (pos == -1) { - var seq = head; - // send acknowledgement - this.ackSender_.send('ACK:' + seq); - this.deliverPayload_(frame); - } else { - var seq = head.substring(0, pos); - // send acknowledgement - this.ackSender_.send('ACK:' + seq); - - var partInfo = head.substring(pos + 1).split('/'); - var part0 = parseInt(partInfo[0], 10); - var part1 = parseInt(partInfo[1], 10); - // create an array to accumulate the parts if this is the - // first frame of a message - if (part0 == 1) { - this.parts_ = []; - } - this.parts_.push(frame); - // deliver the message if this was the last frame of a message - if (part0 == part1) { - this.deliverPayload_(this.parts_.join('')); - delete this.parts_; - } - } - } else { - goog.net.xpc.logger.warning('received msg, but channel is not connected'); - } -}; - - -/** - * Process an incoming acknowdedgement. - * @param {string} msgStr The incoming ack string to process. - */ -goog.net.xpc.IframePollingTransport.prototype.processIncomingAck = - function(msgStr) { - goog.net.xpc.logger.finest('ack received: ' + msgStr); - - if (msgStr == goog.net.xpc.SETUP_ACK_) { - this.waitForAck_ = false; - this.rcvdConnectionSetupAck_ = true; - // send the next frame - this.checkIfConnected_(); - - } else if (this.channel_.isConnected()) { - if (!this.waitForAck_) { - goog.net.xpc.logger.warning('got unexpected ack'); - return; - } - - var seq = parseInt(msgStr.split(':')[1], 10); - if (seq == this.sequence_) { - this.waitForAck_ = false; - this.sendNextFrame_(); - } else { - goog.net.xpc.logger.warning('got ack with wrong sequence'); - } - } else { - goog.net.xpc.logger.warning('received ack, but channel not connected'); - } -}; - - -/** - * Sends a frame (message part). - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.sendNextFrame_ = function() { - // do nothing if we are waiting for an acknowledgement or the - // queue is emtpy - if (this.waitForAck_ || !this.sendQueue_.length) { - return; - } - - var s = this.sendQueue_.shift(); - ++this.sequence_; - this.msgSender_.send(this.sequence_ + s); - goog.net.xpc.logger.finest('msg sent: ' + this.sequence_ + s); - - - this.waitForAck_ = true; -}; - - -/** - * Delivers a message. - * @param {string} s The complete message string ("<service_name>:<payload>"). - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.deliverPayload_ = function(s) { - // determine the service name and the payload - var pos = s.indexOf(':'); - var service = s.substr(0, pos); - var payload = s.substring(pos + 1); - - // deliver the message - if (!this.channel_.isConnected()) { - // as valid messages can come in before a SETUP_ACK has - // been received (because subchannels for msgs and acks are independent), - // delay delivery of early messages until after 'connect'-event - (this.deliveryQueue_ || (this.deliveryQueue_ = [])). - push({service: service, payload: payload}); - goog.net.xpc.logger.finest('queued delivery'); - } else { - this.channel_.xpcDeliver(service, payload); - } -}; - - -// ---- send message ---- - - -/** - * Maximal frame length. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.prototype.MAX_FRAME_LENGTH_ = 3800; - - -/** - * Sends a message. Splits it in multiple frames if too long (exceeds IE's - * URL-length maximum. - * Wireformat: <seq>[,<frame_no>/<#frames>]|<frame_content> - * - * @param {string} service Name of service this the message has to be delivered. - * @param {string} payload The message content. - * @override - */ -goog.net.xpc.IframePollingTransport.prototype.send = - function(service, payload) { - var frame = service + ':' + payload; - // put in queue - if (!goog.userAgent.IE || payload.length <= this.MAX_FRAME_LENGTH_) { - this.sendQueue_.push('|' + frame); - } - else { - var l = payload.length; - var num = Math.ceil(l / this.MAX_FRAME_LENGTH_); // number of frames - var pos = 0; - var i = 1; - while (pos < l) { - this.sendQueue_.push(',' + i + '/' + num + '|' + - frame.substr(pos, this.MAX_FRAME_LENGTH_)); - i++; - pos += this.MAX_FRAME_LENGTH_; - } - } - this.sendNextFrame_(); -}; - - -/** @override */ -goog.net.xpc.IframePollingTransport.prototype.disposeInternal = function() { - goog.base(this, 'disposeInternal'); - - var receivers = goog.net.xpc.IframePollingTransport.receivers_; - goog.array.remove(receivers, this.msgReceiver_); - goog.array.remove(receivers, this.ackReceiver_); - this.msgReceiver_ = this.ackReceiver_ = null; - - goog.dom.removeNode(this.msgIframeElm_); - goog.dom.removeNode(this.ackIframeElm_); - this.msgIframeElm_ = this.ackIframeElm_ = null; - this.msgWinObj_ = this.ackWinObj_ = null; -}; - - -/** - * Array holding all Receiver-instances. - * @type {Array.<goog.net.xpc.IframePollingTransport.Receiver>} - * @private - */ -goog.net.xpc.IframePollingTransport.receivers_ = []; - - -/** - * Short polling interval. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.TIME_POLL_SHORT_ = 10; - - -/** - * Long polling interval. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.TIME_POLL_LONG_ = 100; - - -/** - * Period how long to use TIME_POLL_SHORT_ before raising polling-interval - * to TIME_POLL_LONG_ after an activity. - * @type {number} - * @private - */ -goog.net.xpc.IframePollingTransport.TIME_SHORT_POLL_AFTER_ACTIVITY_ = - 1000; - - -/** - * Polls all receivers. - * @private - */ -goog.net.xpc.IframePollingTransport.receive_ = function() { - var receivers = goog.net.xpc.IframePollingTransport.receivers_; - var receiver; - var rcvd = false; - - /** @preserveTry */ - try { - for (var i = 0; receiver = receivers[i]; i++) { - rcvd = rcvd || receiver.receive(); - } - } catch (e) { - goog.net.xpc.logger.info('receive_() failed: ' + e); - - // Notify the channel that the transport had an error. - receiver.transport_.channel_.notifyTransportError(); - - // notifyTransportError() closes the channel and disposes the transport. - // If there are no other channels present, this.receivers_ will now be empty - // and there is no need to keep polling. - if (!receivers.length) { - return; - } - } - - var now = goog.now(); - if (rcvd) { - goog.net.xpc.IframePollingTransport.lastActivity_ = now; - } - - // Schedule next check. - var t = now - goog.net.xpc.IframePollingTransport.lastActivity_ < - goog.net.xpc.IframePollingTransport.TIME_SHORT_POLL_AFTER_ACTIVITY_ ? - goog.net.xpc.IframePollingTransport.TIME_POLL_SHORT_ : - goog.net.xpc.IframePollingTransport.TIME_POLL_LONG_; - goog.net.xpc.IframePollingTransport.rcvTimer_ = window.setTimeout( - goog.net.xpc.IframePollingTransport.receiveCb_, t); -}; - - -/** - * Callback that wraps receive_ to be used in timers. - * @type {Function} - * @private - */ -goog.net.xpc.IframePollingTransport.receiveCb_ = goog.bind( - goog.net.xpc.IframePollingTransport.receive_, - goog.net.xpc.IframePollingTransport); - - -/** - * Starts the polling loop. - * @private - */ -goog.net.xpc.IframePollingTransport.startRcvTimer_ = function() { - goog.net.xpc.logger.fine('starting receive-timer'); - goog.net.xpc.IframePollingTransport.lastActivity_ = goog.now(); - if (goog.net.xpc.IframePollingTransport.rcvTimer_) { - window.clearTimeout(goog.net.xpc.IframePollingTransport.rcvTimer_); - } - goog.net.xpc.IframePollingTransport.rcvTimer_ = window.setTimeout( - goog.net.xpc.IframePollingTransport.receiveCb_, - goog.net.xpc.IframePollingTransport.TIME_POLL_SHORT_); -}; - - - -/** - * goog.net.xpc.IframePollingTransport.Sender - * - * Utility class to send message-parts to a document from a different origin. - * - * @constructor - * @param {string} url The url the other document will use for polling. - * @param {Object} windowObj The frame used for sending information to. - */ -goog.net.xpc.IframePollingTransport.Sender = function(url, windowObj) { - /** - * The URI used to sending messages. - * @type {string} - * @private - */ - this.sendUri_ = url; - - /** - * The window object of the iframe used to send messages. - * The script instantiating the Sender won't have access to - * the content of sendFrame_. - * @type {Object} - * @private - */ - this.sendFrame_ = windowObj; - - /** - * Cycle counter (used to make sure that sending two identical messages sent - * in direct succession can be recognized as such by the receiver). - * @type {number} - * @private - */ - this.cycle_ = 0; -}; - - -/** - * Sends a message-part (frame) to the peer. - * The message-part is encoded and put in the fragment identifier - * of the URL used for sending (and belongs to the origin/domain of the peer). - * @param {string} payload The message to send. - */ -goog.net.xpc.IframePollingTransport.Sender.prototype.send = function(payload) { - this.cycle_ = ++this.cycle_ % 2; - - var url = this.sendUri_ + '#' + this.cycle_ + encodeURIComponent(payload); - - // TODO(user) Find out if try/catch is still needed - /** @preserveTry */ - try { - // safari doesn't allow to call location.replace() - if (goog.userAgent.WEBKIT) { - this.sendFrame_.location.href = url; - } else { - this.sendFrame_.location.replace(url); - } - } catch (e) { - goog.net.xpc.logger.severe('sending failed', e); - } - - // Restart receiver timer on short polling interval, to support use-cases - // where we need to capture responses quickly. - goog.net.xpc.IframePollingTransport.startRcvTimer_(); -}; - - - -/** - * goog.net.xpc.IframePollingTransport.Receiver - * - * @constructor - * @param {goog.net.xpc.IframePollingTransport} transport The transport to - * receive from. - * @param {Object} windowObj The window-object to poll for location-changes. - * @param {Function} callback The callback-function to be called when - * location has changed. - */ -goog.net.xpc.IframePollingTransport.Receiver = function(transport, - windowObj, - callback) { - /** - * The transport to receive from. - * @type {goog.net.xpc.IframePollingTransport} - * @private - */ - this.transport_ = transport; - this.rcvFrame_ = windowObj; - - this.cb_ = callback; - this.currentLoc_ = this.rcvFrame_.location.href.split('#')[0] + '#INITIAL'; - - goog.net.xpc.IframePollingTransport.receivers_.push(this); - goog.net.xpc.IframePollingTransport.startRcvTimer_(); -}; - - -/** - * Polls the location of the receiver-frame for changes. - * @return {boolean} Whether a change has been detected. - */ -goog.net.xpc.IframePollingTransport.Receiver.prototype.receive = function() { - var loc = this.rcvFrame_.location.href; - - if (loc != this.currentLoc_) { - this.currentLoc_ = loc; - var payload = loc.split('#')[1]; - if (payload) { - payload = payload.substr(1); // discard first character (cycle) - this.cb_(decodeURIComponent(payload)); - } - return true; - } else { - return false; - } -}; |