3 * External storage in a file backend.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
24 * File backend accessable external objects.
26 * In this system, each store "location" maps to the name of a file backend.
27 * The file backends must be defined in $wgFileBackends and must be global
28 * and fully qualified with a global "wikiId" prefix in the configuration.
30 * @ingroup ExternalStorage
33 class ExternalStoreMwstore
extends ExternalStoreMedium
{
35 * The URL returned is of the form of the form mwstore://backend/container/wiki/id
37 * @see ExternalStoreMedium::fetchFromURL()
39 public function fetchFromURL( $url ) {
40 $be = FileBackendGroup
::singleton()->backendFromPath( $url );
41 if ( $be instanceof FileBackend
) {
42 // We don't need "latest" since objects are immutable and
43 // backends should at least have "read-after-create" consistency.
44 return $be->getFileContents( array( 'src' => $url ) );
50 * Fetch data from given external store URLs.
51 * The URL returned is of the form of the form mwstore://backend/container/wiki/id
53 * @param array $urls An array of external store URLs
54 * @return array A map from url to stored content. Failed results are not represented.
56 public function batchFetchFromURLs( array $urls ) {
57 $pathsByBackend = array();
58 foreach ( $urls as $url ) {
59 $be = FileBackendGroup
::singleton()->backendFromPath( $url );
60 if ( $be instanceof FileBackend
) {
61 $pathsByBackend[$be->getName()][] = $url;
65 foreach ( $pathsByBackend as $backendName => $paths ) {
66 $be = FileBackendGroup
::get( $backendName );
67 $blobs = $blobs +
$be->getFileContentsMulti( array( 'srcs' => $paths ) );
73 * @see ExternalStoreMedium::store()
75 public function store( $backend, $data ) {
76 $be = FileBackendGroup
::singleton()->get( $backend );
77 if ( $be instanceof FileBackend
) {
78 // Get three random base 36 characters to act as shard directories
79 $rand = wfBaseConvert( mt_rand( 0, 46655 ), 10, 36, 3 );
80 // Make sure ID is roughly lexicographically increasing for performance
81 $id = str_pad( UIDGenerator
::newTimestampedUID128( 32 ), 26, '0', STR_PAD_LEFT
);
82 // Segregate items by wiki ID for the sake of bookkeeping
83 $wiki = isset( $this->params
['wiki'] ) ?
$this->params
['wiki'] : wfWikiID();
85 $url = $be->getContainerStoragePath( 'data' ) . '/' .
86 rawurlencode( $wiki ) . "/{$rand[0]}/{$rand[1]}/{$rand[2]}/{$id}";
88 $be->prepare( array( 'dir' => dirname( $url ), 'noAccess' => 1, 'noListing' => 1 ) );
89 if ( $be->create( array( 'dst' => $url, 'content' => $data ) )->isOK() ) {