WordPress/wp-includes/js/heartbeat.js
2014-08-13 03:56:17 +00:00

739 lines
18 KiB
JavaScript

/**
* Heartbeat API
*
* Heartbeat is a simple server polling API that sends XHR requests to
* the server every 15 - 60 seconds and triggers events (or callbacks) upon
* receiving data. Currently these 'ticks' handle transports for post locking,
* login-expiration warnings, autosave, and related tasks while a user is logged in.
*
* Available PHP filters (in ajax-actions.php):
* - heartbeat_received
* - heartbeat_send
* - heartbeat_tick
* - heartbeat_nopriv_received
* - heartbeat_nopriv_send
* - heartbeat_nopriv_tick
* @see wp_ajax_nopriv_heartbeat(), wp_ajax_heartbeat()
*
* Custom jQuery events:
* - heartbeat-send
* - heartbeat-tick
* - heartbeat-error
* - heartbeat-connection-lost
* - heartbeat-connection-restored
* - heartbeat-nonces-expired
*
* @since 3.6.0
*/
( function( $, window, undefined ) {
var Heartbeat = function() {
var $document = $(document),
settings = {
// Suspend/resume
suspend: false,
// Whether suspending is enabled
suspendEnabled: true,
// Current screen id, defaults to the JS global 'pagenow' when present (in the admin) or 'front'
screenId: '',
// XHR request URL, defaults to the JS global 'ajaxurl' when present
url: '',
// Timestamp, start of the last connection request
lastTick: 0,
// Container for the enqueued items
queue: {},
// Connect interval (in seconds)
mainInterval: 60,
// Used when the interval is set to 5 sec. temporarily
tempInterval: 0,
// Used when the interval is reset
originalInterval: 0,
// Used together with tempInterval
countdown: 0,
// Whether a connection is currently in progress
connecting: false,
// Whether a connection error occurred
connectionError: false,
// Used to track non-critical errors
errorcount: 0,
// Whether at least one connection has completed successfully
hasConnected: false,
// Whether the current browser window is in focus and the user is active
hasFocus: true,
// Timestamp, last time the user was active. Checked every 30 sec.
userActivity: 0,
// Flags whether events tracking user activity were set
userActivityEvents: false,
// References to various timeouts
beatTimer: 0,
winBlurTimer: 0,
frameBlurTimer: 0
};
/**
* Set local vars and events, then start
*
* @access private
*
* @return void
*/
function initialize() {
if ( typeof window.pagenow === 'string' ) {
settings.screenId = window.pagenow;
}
if ( typeof window.ajaxurl === 'string' ) {
settings.url = window.ajaxurl;
}
// Pull in options passed from PHP
if ( typeof window.heartbeatSettings === 'object' ) {
var options = window.heartbeatSettings;
// The XHR URL can be passed as option when window.ajaxurl is not set
if ( ! settings.url && options.ajaxurl ) {
settings.url = options.ajaxurl;
}
// The interval can be from 15 to 60 sec. and can be set temporarily to 5 sec.
if ( options.interval ) {
settings.mainInterval = options.interval;
if ( settings.mainInterval < 15 ) {
settings.mainInterval = 15;
} else if ( settings.mainInterval > 60 ) {
settings.mainInterval = 60;
}
}
// 'screenId' can be added from settings on the front-end where the JS global 'pagenow' is not set
if ( ! settings.screenId ) {
settings.screenId = options.screenId || 'front';
}
if ( options.suspension === 'disable' ) {
settings.suspendEnabled = false;
}
}
// Convert to milliseconds
settings.mainInterval = settings.mainInterval * 1000;
settings.originalInterval = settings.mainInterval;
// Set focus/blur events on the window
$(window).on( 'blur.wp-heartbeat-focus', function() {
setFrameFocusEvents();
// We don't know why the 'blur' was fired. Either the user clicked in an iframe or outside the browser.
// Running blurred() after some timeout lets us cancel it if the user clicked in an iframe.
settings.winBlurTimer = window.setTimeout( function(){ blurred(); }, 500 );
}).on( 'focus.wp-heartbeat-focus', function() {
removeFrameFocusEvents();
focused();
}).on( 'unload.wp-heartbeat', function() {
// Don't connect any more
settings.suspend = true;
// Abort the last request if not completed
if ( settings.xhr && settings.xhr.readyState !== 4 ) {
settings.xhr.abort();
}
});
// Check for user activity every 30 seconds.
window.setInterval( function(){ checkUserActivity(); }, 30000 );
// Start one tick after DOM ready
$document.ready( function() {
settings.lastTick = time();
scheduleNextTick();
});
}
/**
* Return the current time according to the browser
*
* @access private
*
* @return int
*/
function time() {
return (new Date()).getTime();
}
/**
* Check if the iframe is from the same origin
*
* @access private
*
* @return bool
*/
function isLocalFrame( frame ) {
var origin, src = frame.src;
// Need to compare strings as WebKit doesn't throw JS errors when iframes have different origin.
// It throws uncatchable exceptions.
if ( src && /^https?:\/\//.test( src ) ) {
origin = window.location.origin ? window.location.origin : window.location.protocol + '//' + window.location.host;
if ( src.indexOf( origin ) !== 0 ) {
return false;
}
}
try {
if ( frame.contentWindow.document ) {
return true;
}
} catch(e) {}
return false;
}
/**
* Set error state and fire an event on XHR errors or timeout
*
* @access private
*
* @param string error The error type passed from the XHR
* @param int status The HTTP status code passed from jqXHR (200, 404, 500, etc.)
* @return void
*/
function setErrorState( error, status ) {
var trigger;
if ( error ) {
switch ( error ) {
case 'abort':
// do nothing
break;
case 'timeout':
// no response for 30 sec.
trigger = true;
break;
case 'error':
if ( 503 === status && settings.hasConnected ) {
trigger = true;
break;
}
/* falls through */
case 'parsererror':
case 'empty':
case 'unknown':
settings.errorcount++;
if ( settings.errorcount > 2 && settings.hasConnected ) {
trigger = true;
}
break;
}
if ( trigger && ! hasConnectionError() ) {
settings.connectionError = true;
$document.trigger( 'heartbeat-connection-lost', [error, status] );
}
}
}
/**
* Clear the error state and fire an event
*
* @access private
*
* @return void
*/
function clearErrorState() {
// Has connected successfully
settings.hasConnected = true;
if ( hasConnectionError() ) {
settings.errorcount = 0;
settings.connectionError = false;
$document.trigger( 'heartbeat-connection-restored' );
}
}
/**
* Gather the data and connect to the server
*
* @access private
*
* @return void
*/
function connect() {
var ajaxData, heartbeatData;
// If the connection to the server is slower than the interval,
// heartbeat connects as soon as the previous connection's response is received.
if ( settings.connecting || settings.suspend ) {
return;
}
settings.lastTick = time();
heartbeatData = $.extend( {}, settings.queue );
// Clear the data queue, anything added after this point will be send on the next tick
settings.queue = {};
$document.trigger( 'heartbeat-send', [ heartbeatData ] );
ajaxData = {
data: heartbeatData,
interval: settings.tempInterval ? settings.tempInterval / 1000 : settings.mainInterval / 1000,
_nonce: typeof window.heartbeatSettings === 'object' ? window.heartbeatSettings.nonce : '',
action: 'heartbeat',
screen_id: settings.screenId,
has_focus: settings.hasFocus
};
settings.connecting = true;
settings.xhr = $.ajax({
url: settings.url,
type: 'post',
timeout: 30000, // throw an error if not completed after 30 sec.
data: ajaxData,
dataType: 'json'
}).always( function() {
settings.connecting = false;
scheduleNextTick();
}).done( function( response, textStatus, jqXHR ) {
var newInterval;
if ( ! response ) {
setErrorState( 'empty' );
return;
}
clearErrorState();
if ( response.nonces_expired ) {
$document.trigger( 'heartbeat-nonces-expired' );
return;
}
// Change the interval from PHP
if ( response.heartbeat_interval ) {
newInterval = response.heartbeat_interval;
delete response.heartbeat_interval;
}
$document.trigger( 'heartbeat-tick', [response, textStatus, jqXHR] );
// Do this last, can trigger the next XHR if connection time > 5 sec. and newInterval == 'fast'
if ( newInterval ) {
interval( newInterval );
}
}).fail( function( jqXHR, textStatus, error ) {
setErrorState( textStatus || 'unknown', jqXHR.status );
$document.trigger( 'heartbeat-error', [jqXHR, textStatus, error] );
});
}
/**
* Schedule the next connection
*
* Fires immediately if the connection time is longer than the interval.
*
* @access private
*
* @return void
*/
function scheduleNextTick() {
var delta = time() - settings.lastTick,
interval = settings.mainInterval;
if ( settings.suspend ) {
return;
}
if ( ! settings.hasFocus ) {
interval = 120000; // 120 sec. Post locks expire after 150 sec.
} else if ( settings.countdown > 0 && settings.tempInterval ) {
interval = settings.tempInterval;
settings.countdown--;
if ( settings.countdown < 1 ) {
settings.tempInterval = 0;
}
}
window.clearTimeout( settings.beatTimer );
if ( delta < interval ) {
settings.beatTimer = window.setTimeout(
function() {
connect();
},
interval - delta
);
} else {
connect();
}
}
/**
* Set the internal state when the browser window looses focus
*
* @access private
*
* @return void
*/
function blurred() {
clearFocusTimers();
settings.hasFocus = false;
}
/**
* Set the internal state when the browser window is focused
*
* @access private
*
* @return void
*/
function focused() {
clearFocusTimers();
settings.userActivity = time();
// Resume if suspended
settings.suspend = false;
if ( ! settings.hasFocus ) {
settings.hasFocus = true;
scheduleNextTick();
}
}
/**
* Add focus/blur events to all local iframes
*
* Used to detect when focus is moved from the main window to an iframe
*
* @access private
*
* @return void
*/
function setFrameFocusEvents() {
$('iframe').each( function( i, frame ) {
if ( ! isLocalFrame( frame ) ) {
return;
}
if ( $.data( frame, 'wp-heartbeat-focus' ) ) {
return;
}
$.data( frame, 'wp-heartbeat-focus', 1 );
$( frame.contentWindow ).on( 'focus.wp-heartbeat-focus', function() {
focused();
}).on('blur.wp-heartbeat-focus', function() {
setFrameFocusEvents();
// We don't know why 'blur' was fired. Either the user clicked in the main window or outside the browser.
// Running blurred() after some timeout lets us cancel it if the user clicked in the main window.
settings.frameBlurTimer = window.setTimeout( function(){ blurred(); }, 500 );
});
});
}
/**
* Remove the focus/blur events to all local iframes
*
* @access private
*
* @return void
*/
function removeFrameFocusEvents() {
$('iframe').each( function( i, frame ) {
if ( ! isLocalFrame( frame ) ) {
return;
}
$.removeData( frame, 'wp-heartbeat-focus' );
$( frame.contentWindow ).off( '.wp-heartbeat-focus' );
});
}
/**
* Clear the reset timers for focus/blur events on the window and iframes
*
* @access private
*
* @return void
*/
function clearFocusTimers() {
window.clearTimeout( settings.winBlurTimer );
window.clearTimeout( settings.frameBlurTimer );
}
/**
* Runs when the user becomes active after a period of inactivity
*
* @access private
*
* @return void
*/
function userIsActive() {
settings.userActivityEvents = false;
$document.off( '.wp-heartbeat-active' );
$('iframe').each( function( i, frame ) {
if ( ! isLocalFrame( frame ) ) {
return;
}
$( frame.contentWindow ).off( '.wp-heartbeat-active' );
});
focused();
}
/**
* Check for user activity
*
* Runs every 30 sec.
* Sets 'hasFocus = true' if user is active and the window is in the background.
* Set 'hasFocus = false' if the user has been inactive (no mouse or keyboard activity)
* for 5 min. even when the window has focus.
*
* @access private
*
* @return void
*/
function checkUserActivity() {
var lastActive = settings.userActivity ? time() - settings.userActivity : 0;
if ( lastActive > 300000 && settings.hasFocus ) {
// Throttle down when no mouse or keyboard activity for 5 min
blurred();
}
if ( settings.suspendEnabled && lastActive > 1200000 ) {
// Suspend after 20 min. of inactivity
settings.suspend = true;
}
if ( ! settings.userActivityEvents ) {
$document.on( 'mouseover.wp-heartbeat-active keyup.wp-heartbeat-active', function(){ userIsActive(); } );
$('iframe').each( function( i, frame ) {
if ( ! isLocalFrame( frame ) ) {
return;
}
$( frame.contentWindow ).on( 'mouseover.wp-heartbeat-active keyup.wp-heartbeat-active', function(){ userIsActive(); } );
});
settings.userActivityEvents = true;
}
}
// Public methods
/**
* Whether the window (or any local iframe in it) has focus, or the user is active
*
* @return bool
*/
function hasFocus() {
return settings.hasFocus;
}
/**
* Whether there is a connection error
*
* @return bool
*/
function hasConnectionError() {
return settings.connectionError;
}
/**
* Connect asap regardless of 'hasFocus'
*
* Will not open two concurrent connections. If a connection is in progress,
* will connect again immediately after the current connection completes.
*
* @return void
*/
function connectNow() {
settings.lastTick = 0;
scheduleNextTick();
}
/**
* Disable suspending
*
* Should be used only when Heartbeat is performing critical tasks like autosave, post-locking, etc.
* Using this on many screens may overload the user's hosting account if several
* browser windows/tabs are left open for a long time.
*
* @return void
*/
function disableSuspend() {
settings.suspendEnabled = false;
}
/**
* Get/Set the interval
*
* When setting to 'fast' or 5, by default interval is 5 sec. for the next 30 ticks (for 2 min and 30 sec).
* In this case the number of 'ticks' can be passed as second argument.
* If the window doesn't have focus, the interval slows down to 2 min.
*
* @param mixed speed Interval: 'fast' or 5, 15, 30, 60
* @param string ticks Used with speed = 'fast' or 5, how many ticks before the interval reverts back
* @return int Current interval in seconds
*/
function interval( speed, ticks ) {
var newInterval,
oldInterval = settings.tempInterval ? settings.tempInterval : settings.mainInterval;
if ( speed ) {
switch ( speed ) {
case 'fast':
case 5:
newInterval = 5000;
break;
case 15:
newInterval = 15000;
break;
case 30:
newInterval = 30000;
break;
case 60:
newInterval = 60000;
break;
case 'long-polling':
// Allow long polling, (experimental)
settings.mainInterval = 0;
return 0;
default:
newInterval = settings.originalInterval;
}
if ( 5000 === newInterval ) {
ticks = parseInt( ticks, 10 ) || 30;
ticks = ticks < 1 || ticks > 30 ? 30 : ticks;
settings.countdown = ticks;
settings.tempInterval = newInterval;
} else {
settings.countdown = 0;
settings.tempInterval = 0;
settings.mainInterval = newInterval;
}
// Change the next connection time if new interval has been set.
// Will connect immediately if the time since the last connection
// is greater than the new interval.
if ( newInterval !== oldInterval ) {
scheduleNextTick();
}
}
return settings.tempInterval ? settings.tempInterval / 1000 : settings.mainInterval / 1000;
}
/**
* Enqueue data to send with the next XHR
*
* As the data is send asynchronously, this function doesn't return the XHR response.
* To see the response, use the custom jQuery event 'heartbeat-tick' on the document, example:
* $(document).on( 'heartbeat-tick.myname', function( event, data, textStatus, jqXHR ) {
* // code
* });
* If the same 'handle' is used more than once, the data is not overwritten when the third argument is 'true'.
* Use wp.heartbeat.isQueued('handle') to see if any data is already queued for that handle.
*
* $param string handle Unique handle for the data. The handle is used in PHP to receive the data.
* $param mixed data The data to send.
* $param bool noOverwrite Whether to overwrite existing data in the queue.
* $return bool Whether the data was queued or not.
*/
function enqueue( handle, data, noOverwrite ) {
if ( handle ) {
if ( noOverwrite && this.isQueued( handle ) ) {
return false;
}
settings.queue[handle] = data;
return true;
}
return false;
}
/**
* Check if data with a particular handle is queued
*
* $param string handle The handle for the data
* $return bool Whether some data is queued with this handle
*/
function isQueued( handle ) {
if ( handle ) {
return settings.queue.hasOwnProperty( handle );
}
}
/**
* Remove data with a particular handle from the queue
*
* $param string handle The handle for the data
* $return void
*/
function dequeue( handle ) {
if ( handle ) {
delete settings.queue[handle];
}
}
/**
* Get data that was enqueued with a particular handle
*
* $param string handle The handle for the data
* $return mixed The data or undefined
*/
function getQueuedItem( handle ) {
if ( handle ) {
return this.isQueued( handle ) ? settings.queue[handle] : undefined;
}
}
initialize();
// Expose public methods
return {
hasFocus: hasFocus,
connectNow: connectNow,
disableSuspend: disableSuspend,
interval: interval,
hasConnectionError: hasConnectionError,
enqueue: enqueue,
dequeue: dequeue,
isQueued: isQueued,
getQueuedItem: getQueuedItem
};
};
// Ensure the global `wp` object exists.
window.wp = window.wp || {};
window.wp.heartbeat = new Heartbeat();
}( jQuery, window ));