MediaWiki REL1_34
ExternalStoreMwstore.php
Go to the documentation of this file.
1<?php
35 private $fbGroup;
36
42 public function __construct( array $params ) {
43 parent::__construct( $params );
44 if ( !isset( $params['fbGroup'] ) || !( $params['fbGroup'] instanceof FileBackendGroup ) ) {
45 throw new InvalidArgumentException( "FileBackendGroup required in 'fbGroup' field." );
46 }
47 $this->fbGroup = $params['fbGroup'];
48 }
49
57 public function fetchFromURL( $url ) {
58 $be = $this->fbGroup->backendFromPath( $url );
59 if ( $be instanceof FileBackend ) {
60 // We don't need "latest" since objects are immutable and
61 // backends should at least have "read-after-create" consistency.
62 return $be->getFileContents( [ 'src' => $url ] );
63 }
64
65 return false;
66 }
67
75 public function batchFetchFromURLs( array $urls ) {
76 $pathsByBackend = [];
77 foreach ( $urls as $url ) {
78 $be = $this->fbGroup->backendFromPath( $url );
79 if ( $be instanceof FileBackend ) {
80 $pathsByBackend[$be->getName()][] = $url;
81 }
82 }
83 $blobs = [];
84 foreach ( $pathsByBackend as $backendName => $paths ) {
85 $be = $this->fbGroup->get( $backendName );
86 $blobs += $be->getFileContentsMulti( [ 'srcs' => $paths ] );
87 }
88
89 return $blobs;
90 }
91
95 public function store( $backend, $data ) {
96 $be = $this->fbGroup->get( $backend );
97 // Get three random base 36 characters to act as shard directories
98 $rand = Wikimedia\base_convert( mt_rand( 0, 46655 ), 10, 36, 3 );
99 // Make sure ID is roughly lexicographically increasing for performance
100 $id = str_pad( UIDGenerator::newTimestampedUID128( 32 ), 26, '0', STR_PAD_LEFT );
101 // Segregate items by DB domain ID for the sake of bookkeeping
102 $domain = $this->isDbDomainExplicit
103 ? $this->dbDomain
104 // @FIXME: this does not include the schema for b/c but it ideally should
105 : WikiMap::getWikiIdFromDbDomain( $this->dbDomain );
106 $url = $be->getContainerStoragePath( 'data' ) . '/' . rawurlencode( $domain );
107 // Use directory/container sharding
108 $url .= ( $be instanceof FSFileBackend )
109 ? "/{$rand[0]}/{$rand[1]}/{$rand[2]}/{$id}" // keep directories small
110 : "/{$rand[0]}/{$rand[1]}/{$id}"; // container sharding is only 2-levels
111
112 $be->prepare( [ 'dir' => dirname( $url ), 'noAccess' => 1, 'noListing' => 1 ] );
113 $status = $be->create( [ 'dst' => $url, 'content' => $data ] );
114
115 if ( $status->isOK() ) {
116 return $url;
117 }
118
119 throw new MWException( __METHOD__ . ": operation failed: $status" );
120 }
121
122 public function isReadOnly( $backend ) {
123 if ( parent::isReadOnly( $backend ) ) {
124 return true;
125 }
126
127 $be = $this->fbGroup->get( $backend );
128
129 return $be ? $be->isReadOnly() : false;
130 }
131}
Key/value blob storage for a particular storage medium type (e.g.
array $params
Usage context options for this instance.
File backend accessible external objects.
batchFetchFromURLs(array $urls)
Fetch data from given external store URLs.
isReadOnly( $backend)
Check if a given location is read-only.
store( $backend, $data)
Insert a data item into a given location.string|bool The URL of the stored data item,...
fetchFromURL( $url)
The URL returned is of the form of the form mwstore://backend/container/wiki/id.
Class for a file system (FS) based file backend.
Class to handle file backend registration.
Base class for all file backend classes (including multi-write backends).
MediaWiki exception.
static newTimestampedUID128( $base=10)
Get a statistically unique 128-bit unsigned integer ID string.