MediaWiki REL1_35
MemcachedBagOStuff.php
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1<?php
30 public function __construct( array $params ) {
31 parent::__construct( $params );
32
33 $this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_BE; // unreliable
34 $this->segmentationSize = $params['maxPreferedKeySize'] ?? 917504; // < 1MiB
35 }
36
45 public function makeKeyInternal( $keyspace, $args ) {
46 // Memcached keys have a maximum length of 255 characters. From that,
47 // subtract the number of characters we need for the keyspace and for
48 // the separator character needed for each argument. To handle some
49 // custom prefixes used by thing like WANObjectCache, limit to 205.
50 $charsLeft = 205 - strlen( $keyspace ) - count( $args );
51
52 foreach ( $args as &$arg ) {
53 $arg = strtr( $arg, ' ', '_' );
54
55 // Make sure %, #, and non-ASCII chars are escaped
56 $arg = preg_replace_callback(
57 '/[^\x21-\x22\x24\x26-\x39\x3b-\x7e]+/',
58 function ( $m ) {
59 return rawurlencode( $m[0] );
60 },
61 $arg
62 );
63
64 // 33 = 32 characters for the MD5 + 1 for the '#' prefix.
65 if ( $charsLeft > 33 && strlen( $arg ) > $charsLeft ) {
66 $arg = '#' . md5( $arg );
67 }
68
69 $charsLeft -= strlen( $arg );
70 }
71
72 if ( $charsLeft < 0 ) {
73 return $keyspace . ':BagOStuff-long-key:##' . md5( implode( ':', $args ) );
74 }
75
76 return $keyspace . ':' . implode( ':', $args );
77 }
78
87 public function validateKeyEncoding( $key ) {
88 if ( preg_match( '/[^\x21-\x7e]+/', $key ) ) {
89 throw new Exception( "Key contains invalid characters: $key" );
90 }
91 return $key;
92 }
93
98 protected function fixExpiry( $exptime ) {
99 if ( $exptime < 0 ) {
100 // The PECL driver does not seem to like negative relative values
101 $expiresAt = $this->getCurrentTime() + $exptime;
102 } elseif ( $this->isRelativeExpiration( $exptime ) ) {
103 // TTLs higher than 30 days will be detected as absolute TTLs
104 // (UNIX timestamps), and will result in the cache entry being
105 // discarded immediately because the expiry is in the past.
106 // Clamp expires >30d at 30d, unless they're >=1e9 in which
107 // case they are likely to really be absolute (1e9 = 2011-09-09)
108 $expiresAt = min( $exptime, self::TTL_MONTH );
109 } else {
110 $expiresAt = $exptime;
111 }
112
113 return (int)$expiresAt;
114 }
115}
Storage medium specific cache for storing items (e.g.
Base class for memcached clients.
makeKeyInternal( $keyspace, $args)
Construct a cache key.
validateKeyEncoding( $key)
Ensure that a key is safe to use (contains no control characters and no characters above the ASCII ra...
__construct(array $params)
if( $line===false) $args
Definition mcc.php:124