MediaWiki  1.28.1
MemcachedBagOStuff.php
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1 <?php
31  protected $client;
32 
33  function __construct( array $params ) {
34  parent::__construct( $params );
35 
36  $this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_BE; // unreliable
37  }
38 
45  protected function applyDefaultParams( $params ) {
46  return $params + [
47  'compress_threshold' => 1500,
48  'connect_timeout' => .5,
49  'debug' => false
50  ];
51  }
52 
53  protected function doGet( $key, $flags = 0 ) {
54  $casToken = null;
55 
56  return $this->getWithToken( $key, $casToken, $flags );
57  }
58 
59  protected function getWithToken( $key, &$casToken, $flags = 0 ) {
60  return $this->client->get( $this->validateKeyEncoding( $key ), $casToken );
61  }
62 
63  public function set( $key, $value, $exptime = 0, $flags = 0 ) {
64  return $this->client->set( $this->validateKeyEncoding( $key ), $value,
65  $this->fixExpiry( $exptime ) );
66  }
67 
68  protected function cas( $casToken, $key, $value, $exptime = 0 ) {
69  return $this->client->cas( $casToken, $this->validateKeyEncoding( $key ),
70  $value, $this->fixExpiry( $exptime ) );
71  }
72 
73  public function delete( $key ) {
74  return $this->client->delete( $this->validateKeyEncoding( $key ) );
75  }
76 
77  public function add( $key, $value, $exptime = 0 ) {
78  return $this->client->add( $this->validateKeyEncoding( $key ), $value,
79  $this->fixExpiry( $exptime ) );
80  }
81 
82  public function merge( $key, callable $callback, $exptime = 0, $attempts = 10, $flags = 0 ) {
83  return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
84  }
85 
86  public function changeTTL( $key, $exptime = 0 ) {
87  return $this->client->touch( $this->validateKeyEncoding( $key ),
88  $this->fixExpiry( $exptime ) );
89  }
90 
96  public function getClient() {
97  return $this->client;
98  }
99 
108  public function makeKeyInternal( $keyspace, $args ) {
109  // Memcached keys have a maximum length of 255 characters. From that,
110  // subtract the number of characters we need for the keyspace and for
111  // the separator character needed for each argument. To handle some
112  // custom prefixes used by thing like WANObjectCache, limit to 205.
113  $charsLeft = 205 - strlen( $keyspace ) - count( $args );
114 
115  $args = array_map(
116  function ( $arg ) use ( &$charsLeft ) {
117  $arg = strtr( $arg, ' ', '_' );
118 
119  // Make sure %, #, and non-ASCII chars are escaped
120  $arg = preg_replace_callback(
121  '/[^\x21-\x22\x24\x26-\x39\x3b-\x7e]+/',
122  function ( $m ) {
123  return rawurlencode( $m[0] );
124  },
125  $arg
126  );
127 
128  // 33 = 32 characters for the MD5 + 1 for the '#' prefix.
129  if ( $charsLeft > 33 && strlen( $arg ) > $charsLeft ) {
130  $arg = '#' . md5( $arg );
131  }
132 
133  $charsLeft -= strlen( $arg );
134  return $arg;
135  },
136  $args
137  );
138 
139  if ( $charsLeft < 0 ) {
140  return $keyspace . ':##' . md5( implode( ':', $args ) );
141  }
142 
143  return $keyspace . ':' . implode( ':', $args );
144  }
145 
154  public function validateKeyEncoding( $key ) {
155  if ( preg_match( '/[^\x21-\x7e]+/', $key ) ) {
156  throw new Exception( "Key contains invalid characters: $key" );
157  }
158  return $key;
159  }
160 
170  function fixExpiry( $expiry ) {
171  if ( $expiry > 2592000 && $expiry < 1000000000 ) {
172  $expiry = 2592000;
173  }
174  return (int)$expiry;
175  }
176 
181  protected function debugLog( $text ) {
182  $this->logger->debug( $text );
183  }
184 
185  public function modifySimpleRelayEvent( array $event ) {
186  if ( array_key_exists( 'val', $event ) ) {
187  $event['flg'] = 0; // data is not serialized nor gzipped (for memcached driver)
188  }
189 
190  return $event;
191  }
192 }
MemcachedClient Memcached $client
the array() calling protocol came about after MediaWiki 1.4rc1.
processing should stop and the error should be shown to the user * false
Definition: hooks.txt:189
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
merge($key, callable $callback, $exptime=0, $attempts=10, $flags=0)
$value
it s the revision text itself In either if gzip is the revision text is gzipped $flags
Definition: hooks.txt:2703
fixExpiry($expiry)
TTLs higher than 30 days will be detected as absolute TTLs (UNIX timestamps), and will result in the ...
string $keyspace
Definition: BagOStuff.php:53
if($line===false) $args
Definition: cdb.php:64
__construct(array $params)
mergeViaCas($key, $callback, $exptime=0, $attempts=10)
Definition: BagOStuff.php:289
makeKeyInternal($keyspace, $args)
Construct a cache key.
$params
validateKeyEncoding($key)
Ensure that a key is safe to use (contains no control characters and no characters above the ASCII ra...
set($key, $value, $exptime=0, $flags=0)
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35
modifySimpleRelayEvent(array $event)
Base class for memcached clients.
doGet($key, $flags=0)
add($key, $value, $exptime=0)
getClient()
Get the underlying client object.
debugLog($text)
Send a debug message to the log.
changeTTL($key, $exptime=0)
applyDefaultParams($params)
Fill in some defaults for missing keys in $params.
getWithToken($key, &$casToken, $flags=0)
cas($casToken, $key, $value, $exptime=0)