<?php
+/**
+ * External storage in SQL database.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
/**
* DB accessable external objects
*/
class ExternalStoreDB {
+ /**
+ * @param $params array
+ */
function __construct( $params = array() ) {
$this->mParams = $params;
}
*/
function &getLoadBalancer( $cluster ) {
$wiki = isset($this->mParams['wiki']) ? $this->mParams['wiki'] : false;
-
+
return wfGetLBFactory()->getExternalLB( $cluster, $wiki );
}
* @return DatabaseBase object
*/
function &getSlave( $cluster ) {
+ global $wgDefaultExternalStore;
+
$wiki = isset($this->mParams['wiki']) ? $this->mParams['wiki'] : false;
$lb =& $this->getLoadBalancer( $cluster );
+
+ if ( !in_array( "DB://" . $cluster, (array)$wgDefaultExternalStore ) ) {
+ wfDebug( "read only external store" );
+ $lb->allowLagged(true);
+ } else {
+ wfDebug( "writable external store" );
+ }
+
return $lb->getConnection( DB_SLAVE, array(), $wiki );
}
/**
* Fetch data from given URL
* @param $url String: an url of the form DB://cluster/id or DB://cluster/id/itemid for concatened storage.
+ * @return mixed
*/
function fetchFromURL( $url ) {
$path = explode( '/', $url );
- $cluster = $path[2];
- $id = $path[3];
+ $cluster = $path[2];
+ $id = $path[3];
if ( isset( $path[4] ) ) {
$itemID = $path[4];
} else {
wfDebug( "ExternalStoreDB::fetchBlob cache miss on $cacheID\n" );
$dbr =& $this->getSlave( $cluster );
- $ret = $dbr->selectField( $this->getTable( $dbr ), 'blob_text', array( 'blob_id' => $id ) );
+ $ret = $dbr->selectField( $this->getTable( $dbr ), 'blob_text', array( 'blob_id' => $id ), __METHOD__ );
if ( $ret === false ) {
wfDebugLog( 'ExternalStoreDB', "ExternalStoreDB::fetchBlob master fallback on $cacheID\n" );
// Try the master
$dbw =& $this->getMaster( $cluster );
- $ret = $dbw->selectField( $this->getTable( $dbw ), 'blob_text', array( 'blob_id' => $id ) );
+ $ret = $dbw->selectField( $this->getTable( $dbw ), 'blob_text', array( 'blob_id' => $id ), __METHOD__ );
if( $ret === false) {
wfDebugLog( 'ExternalStoreDB', "ExternalStoreDB::fetchBlob master failed to find $cacheID\n" );
}
*
* @param $cluster String: the cluster name
* @param $data String: the data item
+ * @throws MWException
* @return string URL
*/
function store( $cluster, $data ) {
$dbw = $this->getMaster( $cluster );
$id = $dbw->nextSequenceValue( 'blob_blob_id_seq' );
- $dbw->insert( $this->getTable( $dbw ),
- array( 'blob_id' => $id, 'blob_text' => $data ),
+ $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->commit();
+ $dbw->commit( __METHOD__ );
}
return "DB://$cluster/$id";
}