diff options
Diffstat (limited to 'www/wiki/includes/externalstore/ExternalStoreMwstore.php')
-rw-r--r-- | www/wiki/includes/externalstore/ExternalStoreMwstore.php | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/www/wiki/includes/externalstore/ExternalStoreMwstore.php b/www/wiki/includes/externalstore/ExternalStoreMwstore.php new file mode 100644 index 00000000..5d7155e8 --- /dev/null +++ b/www/wiki/includes/externalstore/ExternalStoreMwstore.php @@ -0,0 +1,105 @@ +<?php +/** + * External storage in a file backend. + * + * 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 + */ + +/** + * File backend accessible external objects. + * + * In this system, each store "location" maps to the name of a file backend. + * The file backends must be defined in $wgFileBackends and must be global + * and fully qualified with a global "wikiId" prefix in the configuration. + * + * @ingroup ExternalStorage + * @since 1.21 + */ +class ExternalStoreMwstore extends ExternalStoreMedium { + /** + * The URL returned is of the form of the form mwstore://backend/container/wiki/id + * + * @see ExternalStoreMedium::fetchFromURL() + * @param string $url + * @return bool + */ + public function fetchFromURL( $url ) { + $be = FileBackendGroup::singleton()->backendFromPath( $url ); + if ( $be instanceof FileBackend ) { + // We don't need "latest" since objects are immutable and + // backends should at least have "read-after-create" consistency. + return $be->getFileContents( [ 'src' => $url ] ); + } + + return false; + } + + /** + * Fetch data from given external store URLs. + * The URL returned is of the form of the form mwstore://backend/container/wiki/id + * + * @param array $urls An array of external store URLs + * @return array A map from url to stored content. Failed results are not represented. + */ + public function batchFetchFromURLs( array $urls ) { + $pathsByBackend = []; + foreach ( $urls as $url ) { + $be = FileBackendGroup::singleton()->backendFromPath( $url ); + if ( $be instanceof FileBackend ) { + $pathsByBackend[$be->getName()][] = $url; + } + } + $blobs = []; + foreach ( $pathsByBackend as $backendName => $paths ) { + $be = FileBackendGroup::singleton()->get( $backendName ); + $blobs = $blobs + $be->getFileContentsMulti( [ 'srcs' => $paths ] ); + } + + return $blobs; + } + + public function store( $backend, $data ) { + $be = FileBackendGroup::singleton()->get( $backend ); + if ( $be instanceof FileBackend ) { + // Get three random base 36 characters to act as shard directories + $rand = Wikimedia\base_convert( mt_rand( 0, 46655 ), 10, 36, 3 ); + // Make sure ID is roughly lexicographically increasing for performance + $id = str_pad( UIDGenerator::newTimestampedUID128( 32 ), 26, '0', STR_PAD_LEFT ); + // Segregate items by wiki ID for the sake of bookkeeping + $wiki = isset( $this->params['wiki'] ) ? $this->params['wiki'] : wfWikiID(); + + $url = $be->getContainerStoragePath( 'data' ) . '/' . rawurlencode( $wiki ); + $url .= ( $be instanceof FSFileBackend ) + ? "/{$rand[0]}/{$rand[1]}/{$rand[2]}/{$id}" // keep directories small + : "/{$rand[0]}/{$rand[1]}/{$id}"; // container sharding is only 2-levels + + $be->prepare( [ 'dir' => dirname( $url ), 'noAccess' => 1, 'noListing' => 1 ] ); + if ( $be->create( [ 'dst' => $url, 'content' => $data ] )->isOK() ) { + return $url; + } + } + + return false; + } + + public function isReadOnly( $backend ) { + $be = FileBackendGroup::singleton()->get( $backend ); + + return $be ? $be->isReadOnly() : false; + } +} |