Heartbeat API: first run, see #23216

git-svn-id: https://develop.svn.wordpress.org/trunk@23355 602fd350-edb4-49c9-b593-d223f7449a82

wp-admin/admin-ajax.php

@@ -56,7 +56,7 @@ $core_actions_post = array(
 	'save-widget', 'set-post-thumbnail', 'date_format', 'time_format', 'wp-fullscreen-save-post',
 	'wp-remove-post-lock', 'dismiss-wp-pointer', 'upload-attachment', 'get-attachment',
 	'query-attachments', 'save-attachment', 'save-attachment-compat', 'send-link-to-editor',
-	'send-attachment-to-editor', 'save-attachment-order',
+	'send-attachment-to-editor', 'save-attachment-order', 'heartbeat',
 );
 
 // Register core Ajax calls.

wp-admin/includes/ajax-actions.php

@@ -2071,3 +2071,32 @@ function wp_ajax_send_link_to_editor() {
 
 	wp_send_json_success( $html );
 }
+
+function wp_ajax_heartbeat() {
+	check_ajax_referer( 'heartbeat-nonce', '_nonce' );
+	$response = array( 'pagenow' => '' );
+
+	if ( ! empty($_POST['pagenow']) )
+		$response['pagenow'] = sanitize_key($_POST['pagenow']);
+	
+	if ( ! empty($_POST['data']) ) {
+		$data = (array) $_POST['data'];
+		// todo: how much to sanitize and preset and what to leave to be accessed from $data or $_POST..?
+		$user = wp_get_current_user();
+		$data['user_id'] = $user->exists() ? $user->ID : 0;
+
+		// todo: separate filters: 'heartbeat_[action]' so we call different callbacks only when there is data for them,
+		// or all callbacks listen to one filter and run when there is something for them in $data?
+		$response = apply_filters( 'heartbeat_received', $response, $data );
+	}
+
+	$response = apply_filters( 'heartbeat_send', $response );
+
+	// Allow the transport to be replaced with long-polling easily
+	do_action( 'heartbeat_tick', $response );
+
+	// always send the current time acording to the server
+	$response['time'] = time();
+
+	wp_send_json($response);
+}

wp-includes/default-filters.php

@@ -290,4 +290,7 @@ add_filter( 'default_option_link_manager_enabled', '__return_true' );
 // This option no longer exists; tell plugins we always support auto-embedding.
 add_filter( 'default_option_embed_autourls', '__return_true' );
 
+// Default settings for heartbeat
+add_filter( 'heartbeat_settings', 'wp_heartbeat_settings' );
+
 unset($filter, $action);

wp-includes/general-template.php

@@ -2284,3 +2284,18 @@ function __checked_selected_helper( $helper, $current, $echo, $type ) {
 
 	return $result;
 }
+
+/**
+ * Default settings for heartbeat
+ *
+ * Outputs the nonce used in the heartbeat XHR
+ *
+ * @since 3.6.0
+ *
+ * @param array $settings
+ * @return array $settings
+ */
+function wp_heartbeat_settings( $settings ) {
+	$setting['nonce'] = wp_create_nonce( 'heartbeat-nonce' );
+	return $setting;
+}

wp-includes/js/heartbeat.js

@@ -0,0 +1,178 @@
+/**
+ * Heartbeat API
+ */
+
+ // Ensure the global `wp` object exists.
+window.wp = window.wp || {};
+
+(function($){
+	var Heartbeat = function() {
+		var self = this,
+			running,
+			timeout,
+			nonce,
+			screen = typeof pagenow != 'undefined' ? pagenow : '',
+			settings,
+			tick = 0,
+			queue = {},
+			interval,
+			lastconnect = 0;
+
+		this.url = typeof ajaxurl != 'undefined' ? ajaxurl : 'wp-admin/admin-ajax.php';
+		this.autostart = true;
+
+		if ( typeof( window.heartbeatSettings != 'undefined' ) ) {
+			settings = $.extend( {}, window.heartbeatSettings );
+			delete window.heartbeatSettings;
+
+			// Add private vars
+			nonce = settings.nonce || '';
+			delete settings.nonce;
+
+			interval = settings.interval || 15000; // default interval
+			delete settings.interval;
+			
+			// todo: needed?
+			// 'pagenow' can be added from settings if not already defined
+			screen = screen || settings.pagenow;
+			delete settings.pagenow;
+
+			// Add public vars
+			$.extend( this, settings );
+		}
+
+		function time(s) {
+			if ( s )
+				return parseInt( (new Date()).getTime() / 1000 );
+
+			return (new Date()).getTime();
+		}
+
+		// Set error state and fire an event if it persists for over 3 min
+		function errorstate() {
+			var since;
+
+			if ( lastconnect ) {
+				since = time() - lastconnect;
+
+				if ( since > 180000 ) {
+					self.connectionLost = true;
+					$(document).trigger( 'heartbeat-connection-lost', parseInt(since / 1000) );
+				} else if ( self.connectionLost ) {
+					self.connectionLost = false;
+					$(document).trigger( 'heartbeat-connection-restored' );
+				}
+			}
+		}
+
+		function connect() {
+			var data = {};
+			tick = time();
+
+			data.data = $.extend( {}, queue );
+			queue = {};
+
+			data.interval = interval / 1000;
+			data._nonce = nonce;
+			data.action = 'heartbeat';
+			data.pagenow = screen;
+
+			self.xhr = $.post( self.url, data, function(r){
+				lastconnect = time();
+				// Clear error state
+				if ( self.connectionLost )
+					errorstate();
+				
+				self.tick(r);
+			}, 'json' ).always( function(){
+				next();
+			}).fail( function(r){
+				errorstate();
+				self.error(r);
+			});
+		};
+
+		function next() {
+			var delta = time() - tick;
+
+			if ( !running )
+				return;
+
+			if ( delta < interval ) {
+				timeout = window.setTimeout(
+					function(){
+						if ( running )
+							connect();
+					},
+					interval - delta
+				);
+			} else {
+				window.clearTimeout(timeout); // this has already expired?
+				connect();
+			}
+		};
+
+		this.interval = function(seconds) {
+			if ( seconds ) {
+				// Limit
+				if ( 5 > seconds || seconds > 60 )
+					return false;
+
+				interval = seconds * 1000;
+			} else if ( seconds === 0 ) {
+				// Allow long polling to be turned on
+				interval = 0;
+			}
+			return interval / 1000;
+		};
+
+		this.start = function() {
+			// start only once
+			if ( running )
+				return false;
+
+			running = true;
+			connect();
+
+			return true;
+		};
+
+		this.stop = function() {
+			if ( !running )
+				return false;
+
+			if ( self.xhr )
+				self.xhr.abort();
+
+			running = false;
+			return true;
+		}
+
+		this.send = function(action, data) {
+			if ( action )
+				queue[action] = data;
+		}
+
+		if ( this.autostart ) {
+			$(document).ready( function(){
+				// Start one tick (15 sec) after DOM ready
+				running = true;
+				tick = time();
+				next();
+			});
+		}
+			
+	}
+
+	$.extend( Heartbeat.prototype, {
+		tick: function(r) {
+			$(document).trigger( 'heartbeat-tick', r );
+		},
+		error: function(r) {
+			$(document).trigger( 'heartbeat-error', r );
+		}
+	});
+
+	wp.heartbeat = new Heartbeat();
+
+}(jQuery));

wp-includes/script-loader.php

@@ -107,6 +107,11 @@ function wp_default_scripts( &$scripts ) {
 	) );
 
 	$scripts->add( 'autosave', "/wp-includes/js/autosave$suffix.js", array('schedule', 'wp-ajax-response'), false, 1 );
+	
+	$scripts->add( 'heartbeat', "/wp-includes/js/heartbeat$suffix.js", array('jquery'), false, 1 );
+	did_action( 'init' ) && $scripts->localize( 'heartbeat', 'heartbeatSettings',
+		apply_filters( 'heartbeat_settings', array() )
+	);
 
 	$scripts->add( 'wp-lists', "/wp-includes/js/wp-lists$suffix.js", array( 'wp-ajax-response', 'jquery-color' ), false, 1 );
 
@@ -371,7 +376,7 @@ function wp_default_scripts( &$scripts ) {
 
 		$scripts->add( 'postbox', "/wp-admin/js/postbox$suffix.js", array('jquery-ui-sortable'), false, 1 );
 
-		$scripts->add( 'post', "/wp-admin/js/post$suffix.js", array('suggest', 'wp-lists', 'postbox'), false, 1 );
+		$scripts->add( 'post', "/wp-admin/js/post$suffix.js", array('suggest', 'wp-lists', 'postbox', 'heartbeat'), false, 1 );
 		did_action( 'init' ) && $scripts->localize( 'post', 'postL10n', array(
 			'ok' => __('OK'),
 			'cancel' => __('Cancel'),