[4] Add revision local cache holder object

Change-Id: I85f68b3ca269c711a8a177e013bd8eba38833444

Echo.php

@@ -70,6 +70,7 @@ $wgAutoloadClasses['EchoUserNotificationGateway'] = $dir . 'includes/gateway/Use
 // Local caches
 $wgAutoloadClasses['EchoLocalCache'] = $dir . 'includes/cache/LocalCache.php';
 $wgAutoloadClasses['EchoTitleLocalCache'] = $dir . 'includes/cache/TitleLocalCache.php';
+$wgAutoloadClasses['EchoRevisionLocalCache'] = $dir . 'includes/cache/RevisionLocalCache.php';
 
 // Output formatters
 $wgAutoloadClasses['EchoDataOutputFormatter'] = $dir . 'includes/DataOutputFormatter.php';

includes/cache/RevisionLocalCache.php

@@ -0,0 +1,68 @@
+<?php
+
+/**
+ * Cache class that maps revision id to Revision object
+ */
+class EchoRevisionLocalCache extends EchoLocalCache {
+
+	/**
+	 * @var EchoRevisionLocalCache
+	 */
+	private static $instance;
+
+	/**
+	 * The current wiki id
+	 * @var string|null
+	 */
+	private static $wiki;
+
+	/**
+	 * Create a EchoRevisionLocalCache object
+	 * @return EchoRevisionLocalCache
+	 */
+	public static function create() {
+		// A job queue may run against multiple wikis,
+		// initialize a new one for the current wiki
+		if ( wfWikiId() != self::$wiki ) {
+			self::$instance = null;
+			self::$wiki = wfWikiId();
+		}
+		if ( !self::$instance ) {
+			self::$instance = new EchoRevisionLocalCache();
+		}
+		return self::$instance;
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	protected function resolve() {
+		if ( $this->lookups ) {
+			// @Todo Add newFromIds() to Revision
+			$dbr = wfGetDB( DB_SLAVE );
+			$fields = array_merge(
+				Revision::selectFields(),
+				Revision::selectPageFields(),
+				Revision::selectUserFields()
+			);
+			$res = $dbr->select(
+				array( 'revision', 'page', 'user' ),
+				$fields,
+				array( 'rev_id' => $this->lookups ),
+				__METHOD__,
+				array(),
+				array(
+					'page' => Revision::pageJoinCond(),
+					'user' => Revision::userJoinCond()
+				)
+			);
+			if ( $res ) {
+				foreach ( $res as $row ) {
+					$this->targets->set( $row->rev_id, new Revision( $row ) );
+				}
+				$this->lookups = array();
+			}
+		}
+	}
+
+}

includes/cache/TitleLocalCache.php

@@ -1,5 +1,8 @@
 <?php
 
+/**
+ * Cache class that maps article id to Title object
+ */
 class EchoTitleLocalCache extends EchoLocalCache {
 
 	/**

model/Event.php

@@ -245,6 +245,10 @@ class EchoEvent extends EchoAbstractEntity{
 			$titleCache = EchoTitleLocalCache::create();
 			$titleCache->add( $row->event_page_id );
 		}
+		if ( isset( $this->extra['revid'] ) && $this->extra['revid'] ) {
+			$revisionCache = EchoRevisionLocalCache::create();
+			$revisionCache->add( $this->extra['revid'] );
+		}
 	}
 
 	/**
@@ -428,6 +432,11 @@ class EchoEvent extends EchoAbstractEntity{
 		if ( $this->revision ) {
 			return $this->revision;
 		} elseif ( isset( $this->extra['revid'] ) ) {
+			$revisionCache = EchoRevisionLocalCache::create();
+			$revision = $revisionCache->get( $this->extra['revid'] );
+			if ( $revision ) {
+				return $this->revision = $revision;
+			}
 			return $this->revision = Revision::newFromId( $this->extra['revid'] );
 		}
 		return null;