MediaWiki 1.17.0

[autoinstallsdev/mediawiki.git] / includes / ExternalStoreDB.php

diff --git a/includes/ExternalStoreDB.php b/includes/ExternalStoreDB.php
index f9046f74c9a58b22806fa59e7b90045e2058d2ae..877277a2806c15318b7e40dfcfddd7c3e7c7a31e 100644 (file)
--- a/includes/ExternalStoreDB.php
+++ b/includes/ExternalStoreDB.php
@@ -1,58 +1,57 @@
 <?php
-/**
- *
- *
- * DB accessable external objects
- *
- */
-
-
-
-/**
- * External database storage will use one (or more) separate connection pools
- * from what the main wiki uses. If we load many revisions, such as when doing
- * bulk backups or maintenance, we want to keep them around over the lifetime
- * of the script.
- *
- * Associative array of LoadBalancer objects, indexed by cluster name.
- */
-global $wgExternalLoadBalancers;
-$wgExternalLoadBalancers = array();
 
 /**
- * One-step cache variable to hold base blobs; operations that
- * pull multiple revisions may often pull multiple times from
- * the same blob. By keeping the last-used one open, we avoid
- * redundant unserialization and decompression overhead.
+ * DB accessable external objects
+ * @ingroup ExternalStorage
  */
-global $wgExternalBlobCache;
-$wgExternalBlobCache = array();
-
 class ExternalStoreDB {
 
-       /** @todo Document.*/
+       function __construct( $params = array() ) {
+               $this->mParams = $params;
+       }
+
+       /**
+        * Get a LoadBalancer for the specified cluster
+        *
+        * @param $cluster String: cluster name
+        * @return LoadBalancer object
+        */
        function &getLoadBalancer( $cluster ) {
-               global $wgExternalServers, $wgExternalLoadBalancers;
-               if ( !array_key_exists( $cluster, $wgExternalLoadBalancers ) ) {
-                       $wgExternalLoadBalancers[$cluster] = LoadBalancer::newFromParams( $wgExternalServers[$cluster] );
-               }
-               $wgExternalLoadBalancers[$cluster]->allowLagged(true);
-               return $wgExternalLoadBalancers[$cluster];
+               $wiki = isset($this->mParams['wiki']) ? $this->mParams['wiki'] : false;
+               
+               return wfGetLBFactory()->getExternalLB( $cluster, $wiki );
        }
 
-       /** @todo Document.*/
+       /**
+        * Get a slave database connection for the specified cluster
+        *
+        * @param $cluster String: cluster name
+        * @return DatabaseBase object
+        */
        function &getSlave( $cluster ) {
+               $wiki = isset($this->mParams['wiki']) ? $this->mParams['wiki'] : false;
                $lb =& $this->getLoadBalancer( $cluster );
-               return $lb->getConnection( DB_SLAVE );
+               return $lb->getConnection( DB_SLAVE, array(), $wiki );
        }
 
-       /** @todo Document.*/
+       /**
+        * Get a master database connection for the specified cluster
+        *
+        * @param $cluster String: cluster name
+        * @return DatabaseBase object
+        */
        function &getMaster( $cluster ) {
+               $wiki = isset($this->mParams['wiki']) ? $this->mParams['wiki'] : false;
                $lb =& $this->getLoadBalancer( $cluster );
-               return $lb->getConnection( DB_MASTER );
+               return $lb->getConnection( DB_MASTER, array(), $wiki );
        }
 
-       /** @todo Document.*/
+       /**
+        * Get the 'blobs' table name for this database
+        *
+        * @param $db DatabaseBase
+        * @return String: table name ('blobs' by default)
+        */
        function getTable( &$db ) {
                $table = $db->getLBInfo( 'blobs table' );
                if ( is_null( $table ) ) {
@@ -63,9 +62,9 @@ class ExternalStoreDB {
 
        /**
         * Fetch data from given URL
-        * @param string $url An url of the form DB://cluster/id or DB://cluster/id/itemid for concatened storage.
+        * @param $url String: an url of the form DB://cluster/id or DB://cluster/id/itemid for concatened storage.
         */
-       function fetchFromURL($url) {
+       function fetchFromURL( $url ) {
                $path = explode( '/', $url );
                $cluster  = $path[2];
                $id       = $path[3];
@@ -94,11 +93,18 @@ class ExternalStoreDB {
         * @private
         */
        function &fetchBlob( $cluster, $id, $itemID ) {
-               global $wgExternalBlobCache;
+               /**
+                * One-step cache variable to hold base blobs; operations that
+                * pull multiple revisions may often pull multiple times from
+                * the same blob. By keeping the last-used one open, we avoid
+                * redundant unserialization and decompression overhead.
+                */
+               static $externalBlobCache = array();
+
                $cacheID = ( $itemID === false ) ? "$cluster/$id" : "$cluster/$id/";
-               if( isset( $wgExternalBlobCache[$cacheID] ) ) {
+               if( isset( $externalBlobCache[$cacheID] ) ) {
                        wfDebug( "ExternalStoreDB::fetchBlob cache hit on $cacheID\n" );
-                       return $wgExternalBlobCache[$cacheID];
+                       return $externalBlobCache[$cacheID];
                }
 
                wfDebug( "ExternalStoreDB::fetchBlob cache miss on $cacheID\n" );
@@ -119,7 +125,7 @@ class ExternalStoreDB {
                        $ret = unserialize( $ret );
                }
 
-               $wgExternalBlobCache = array( $cacheID => &$ret );
+               $externalBlobCache = array( $cacheID => &$ret );
                return $ret;
        }
 
@@ -131,17 +137,18 @@ class ExternalStoreDB {
         * @return string URL
         */
        function store( $cluster, $data ) {
-               $fname = 'ExternalStoreDB::store';
-
-               $dbw =& $this->getMaster( $cluster );
-
+               $dbw = $this->getMaster( $cluster );
                $id = $dbw->nextSequenceValue( 'blob_blob_id_seq' );
-               $dbw->insert( $this->getTable( $dbw ), array( 'blob_id' => $id, 'blob_text' => $data ), $fname );
+               $dbw->insert( $this->getTable( $dbw ), 
+                       array( 'blob_id' => $id, 'blob_text' => $data ), 
+                       __METHOD__ );
                $id = $dbw->insertId();
+               if ( !$id ) {
+                       throw new MWException( __METHOD__.': no insert ID' );
+               }
                if ( $dbw->getFlag( DBO_TRX ) ) {
-                       $dbw->immediateCommit();
+                       $dbw->commit();
                }
                return "DB://$cluster/$id";
        }
 }
-