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RedisConnectionPool.php
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1 <?php
27 
41 class RedisConnectionPool implements LoggerAwareInterface {
43  protected $connectTimeout;
45  protected $readTimeout;
47  protected $password;
49  protected $persistent;
51  protected $serializer;
53  protected $id;
54 
56  protected $idlePoolSize = 0;
57 
59  protected $connections = [];
61  protected $downServers = [];
62 
64  protected static $instances = [];
65 
67  const SERVER_DOWN_TTL = 30;
68 
72  protected $logger;
73 
79  protected function __construct( array $options, $id ) {
80  if ( !class_exists( 'Redis' ) ) {
81  throw new RuntimeException(
82  __CLASS__ . ' requires a Redis client library. ' .
83  'See https://www.mediawiki.org/wiki/Redis#Setup' );
84  }
85  $this->logger = $options['logger'] ?? new NullLogger();
86  $this->connectTimeout = $options['connectTimeout'];
87  $this->readTimeout = $options['readTimeout'];
88  $this->persistent = $options['persistent'];
89  $this->password = $options['password'];
90  if ( !isset( $options['serializer'] ) || $options['serializer'] === 'php' ) {
91  $this->serializer = Redis::SERIALIZER_PHP;
92  } elseif ( $options['serializer'] === 'igbinary' ) {
93  $this->serializer = Redis::SERIALIZER_IGBINARY;
94  } elseif ( $options['serializer'] === 'none' ) {
95  $this->serializer = Redis::SERIALIZER_NONE;
96  } else {
97  throw new InvalidArgumentException( "Invalid serializer specified." );
98  }
99  $this->id = $id;
100  }
101 
102  public function setLogger( LoggerInterface $logger ) {
103  $this->logger = $logger;
104  }
105 
110  protected static function applyDefaultConfig( array $options ) {
111  if ( !isset( $options['connectTimeout'] ) ) {
112  $options['connectTimeout'] = 1;
113  }
114  if ( !isset( $options['readTimeout'] ) ) {
115  $options['readTimeout'] = 1;
116  }
117  if ( !isset( $options['persistent'] ) ) {
118  $options['persistent'] = false;
119  }
120  if ( !isset( $options['password'] ) ) {
121  $options['password'] = null;
122  }
123 
124  return $options;
125  }
126 
142  public static function singleton( array $options ) {
143  $options = self::applyDefaultConfig( $options );
144  // Map the options to a unique hash...
145  ksort( $options ); // normalize to avoid pool fragmentation
146  $id = sha1( serialize( $options ) );
147  // Initialize the object at the hash as needed...
148  if ( !isset( self::$instances[$id] ) ) {
149  self::$instances[$id] = new self( $options, $id );
150  }
151 
152  return self::$instances[$id];
153  }
154 
159  public static function destroySingletons() {
160  self::$instances = [];
161  }
162 
172  public function getConnection( $server, LoggerInterface $logger = null ) {
173  // The above @return also documents 'Redis' for convenience with IDEs.
174  // RedisConnRef uses PHP magic methods, which wouldn't be recognised.
175 
177  // Check the listing "dead" servers which have had a connection errors.
178  // Servers are marked dead for a limited period of time, to
179  // avoid excessive overhead from repeated connection timeouts.
180  if ( isset( $this->downServers[$server] ) ) {
181  $now = time();
182  if ( $now > $this->downServers[$server] ) {
183  // Dead time expired
184  unset( $this->downServers[$server] );
185  } else {
186  // Server is dead
187  $logger->debug(
188  'Server "{redis_server}" is marked down for another ' .
189  ( $this->downServers[$server] - $now ) . 'seconds',
190  [ 'redis_server' => $server ]
191  );
192 
193  return false;
194  }
195  }
196 
197  // Check if a connection is already free for use
198  if ( isset( $this->connections[$server] ) ) {
199  foreach ( $this->connections[$server] as &$connection ) {
200  if ( $connection['free'] ) {
201  $connection['free'] = false;
203 
204  return new RedisConnRef(
205  $this, $server, $connection['conn'], $logger
206  );
207  }
208  }
209  }
210 
211  if ( !$server ) {
212  throw new InvalidArgumentException(
213  __CLASS__ . ": invalid configured server \"$server\"" );
214  } elseif ( substr( $server, 0, 1 ) === '/' ) {
215  // UNIX domain socket
216  // These are required by the redis extension to start with a slash, but
217  // we still need to set the port to a special value to make it work.
218  $host = $server;
219  $port = 0;
220  } else {
221  // TCP connection
222  if ( preg_match( '/^\[(.+)\]:(\d+)$/', $server, $m ) ) {
223  list( $host, $port ) = [ $m[1], (int)$m[2] ]; // (ip, port)
224  } elseif ( preg_match( '/^([^:]+):(\d+)$/', $server, $m ) ) {
225  list( $host, $port ) = [ $m[1], (int)$m[2] ]; // (ip or path, port)
226  } else {
227  list( $host, $port ) = [ $server, 6379 ]; // (ip or path, port)
228  }
229  }
230 
231  $conn = new Redis();
232  try {
233  if ( $this->persistent ) {
234  $result = $conn->pconnect( $host, $port, $this->connectTimeout, $this->id );
235  } else {
236  $result = $conn->connect( $host, $port, $this->connectTimeout );
237  }
238  if ( !$result ) {
239  $logger->error(
240  'Could not connect to server "{redis_server}"',
241  [ 'redis_server' => $server ]
242  );
243  // Mark server down for some time to avoid further timeouts
244  $this->downServers[$server] = time() + self::SERVER_DOWN_TTL;
245 
246  return false;
247  }
248  if ( ( $this->password !== null ) && !$conn->auth( $this->password ) ) {
249  $logger->error(
250  'Authentication error connecting to "{redis_server}"',
251  [ 'redis_server' => $server ]
252  );
253  }
254  } catch ( RedisException $e ) {
255  $this->downServers[$server] = time() + self::SERVER_DOWN_TTL;
256  $logger->error(
257  'Redis exception connecting to "{redis_server}"',
258  [
259  'redis_server' => $server,
260  'exception' => $e,
261  ]
262  );
263 
264  return false;
265  }
266 
267  if ( $conn ) {
268  $conn->setOption( Redis::OPT_READ_TIMEOUT, $this->readTimeout );
269  $conn->setOption( Redis::OPT_SERIALIZER, $this->serializer );
270  $this->connections[$server][] = [ 'conn' => $conn, 'free' => false ];
271 
272  return new RedisConnRef( $this, $server, $conn, $logger );
273  } else {
274  return false;
275  }
276  }
277 
285  public function freeConnection( $server, Redis $conn ) {
286  $found = false;
287 
288  foreach ( $this->connections[$server] as &$connection ) {
289  if ( $connection['conn'] === $conn && !$connection['free'] ) {
290  $connection['free'] = true;
292  break;
293  }
294  }
295 
296  $this->closeExcessIdleConections();
297 
298  return $found;
299  }
300 
304  protected function closeExcessIdleConections() {
305  if ( $this->idlePoolSize <= count( $this->connections ) ) {
306  return; // nothing to do (no more connections than servers)
307  }
308 
309  foreach ( $this->connections as &$serverConnections ) {
310  foreach ( $serverConnections as $key => &$connection ) {
311  if ( $connection['free'] ) {
312  unset( $serverConnections[$key] );
313  if ( --$this->idlePoolSize <= count( $this->connections ) ) {
314  return; // done (no more connections than servers)
315  }
316  }
317  }
318  }
319  }
320 
330  public function handleError( RedisConnRef $cref, RedisException $e ) {
331  $server = $cref->getServer();
332  $this->logger->error(
333  'Redis exception on server "{redis_server}"',
334  [
335  'redis_server' => $server,
336  'exception' => $e,
337  ]
338  );
339  foreach ( $this->connections[$server] as $key => $connection ) {
340  if ( $cref->isConnIdentical( $connection['conn'] ) ) {
341  $this->idlePoolSize -= $connection['free'] ? 1 : 0;
342  unset( $this->connections[$server][$key] );
343  break;
344  }
345  }
346  }
347 
364  public function reauthenticateConnection( $server, Redis $conn ) {
365  if ( $this->password !== null && !$conn->auth( $this->password ) ) {
366  $this->logger->error(
367  'Authentication error connecting to "{redis_server}"',
368  [ 'redis_server' => $server ]
369  );
370 
371  return false;
372  }
373 
374  return true;
375  }
376 
383  public function resetTimeout( Redis $conn, $timeout = null ) {
384  $conn->setOption( Redis::OPT_READ_TIMEOUT, $timeout ?: $this->readTimeout );
385  }
386 
390  function __destruct() {
391  foreach ( $this->connections as $server => &$serverConnections ) {
392  foreach ( $serverConnections as $key => &$connection ) {
393  try {
395  $conn = $connection['conn'];
396  $conn->close();
397  } catch ( RedisException $e ) {
398  // The destructor can be called on shutdown when random parts of the system
399  // have been destructed already, causing weird errors. Ignore them.
400  }
401  }
402  }
403  }
404 }
deferred txt A few of the database updates required by various functions here can be deferred until after the result page is displayed to the user For updating the view updating the linked to tables after a etc PHP does not yet have any way to tell the server to actually return and disconnect while still running these but it might have such a feature in the future We handle these by creating a deferred update object and putting those objects on a global list
Definition: deferred.txt:11
freeConnection( $server, Redis $conn)
Mark a connection to a server as free to return to the pool.
string $id
ID for persistent connections.
processing should stop and the error should be shown to the user * false
Definition: hooks.txt:187
serialize()
reauthenticateConnection( $server, Redis $conn)
Re-send an AUTH request to the redis server (useful after disconnects).
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
bool $persistent
Whether connections persist.
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException' returning false will NOT prevent logging $e
Definition: hooks.txt:2147
string $password
Plaintext auth password.
array $downServers
(server name => UNIX timestamp)
static destroySingletons()
Destroy all singleton() instances.
string $connectTimeout
Connection timeout in seconds.
static applyDefaultConfig(array $options)
handleError(RedisConnRef $cref, RedisException $e)
The redis extension throws an exception in response to various read, write and protocol errors...
array $connections
(server name => ((connection info array),...)
The index of the header message $result[1]=The index of the body text message $result[2 through n]=Parameters passed to body text message. Please note the header message cannot receive/use parameters. 'ImgAuthModifyHeaders':Executed just before a file is streamed to a user via img_auth.php, allowing headers to be modified beforehand. $title:LinkTarget object & $headers:HTTP headers(name=> value, names are case insensitive). Two headers get special handling:If-Modified-Since(value must be a valid HTTP date) and Range(must be of the form "bytes=(\*-\*)") will be honored when streaming the file. 'ImportHandleLogItemXMLTag':When parsing a XML tag in a log item. Return false to stop further processing of the tag $reader:XMLReader object $logInfo:Array of information 'ImportHandlePageXMLTag':When parsing a XML tag in a page. Return false to stop further processing of the tag $reader:XMLReader object & $pageInfo:Array of information 'ImportHandleRevisionXMLTag':When parsing a XML tag in a page revision. Return false to stop further processing of the tag $reader:XMLReader object $pageInfo:Array of page information $revisionInfo:Array of revision information 'ImportHandleToplevelXMLTag':When parsing a top level XML tag. Return false to stop further processing of the tag $reader:XMLReader object 'ImportHandleUnknownUser':When a user doesn 't exist locally, this hook is called to give extensions an opportunity to auto-create it. If the auto-creation is successful, return false. $name:User name 'ImportHandleUploadXMLTag':When parsing a XML tag in a file upload. Return false to stop further processing of the tag $reader:XMLReader object $revisionInfo:Array of information 'ImportLogInterwikiLink':Hook to change the interwiki link used in log entries and edit summaries for transwiki imports. & $fullInterwikiPrefix:Interwiki prefix, may contain colons. & $pageTitle:String that contains page title. 'ImportSources':Called when reading from the $wgImportSources configuration variable. Can be used to lazy-load the import sources list. & $importSources:The value of $wgImportSources. Modify as necessary. See the comment in DefaultSettings.php for the detail of how to structure this array. 'InfoAction':When building information to display on the action=info page. $context:IContextSource object & $pageInfo:Array of information 'InitializeArticleMaybeRedirect':MediaWiki check to see if title is a redirect. & $title:Title object for the current page & $request:WebRequest & $ignoreRedirect:boolean to skip redirect check & $target:Title/string of redirect target & $article:Article object 'InternalParseBeforeLinks':during Parser 's internalParse method before links but after nowiki/noinclude/includeonly/onlyinclude and other processings. & $parser:Parser object & $text:string containing partially parsed text & $stripState:Parser 's internal StripState object 'InternalParseBeforeSanitize':during Parser 's internalParse method just before the parser removes unwanted/dangerous HTML tags and after nowiki/noinclude/includeonly/onlyinclude and other processings. Ideal for syntax-extensions after template/parser function execution which respect nowiki and HTML-comments. & $parser:Parser object & $text:string containing partially parsed text & $stripState:Parser 's internal StripState object 'InterwikiLoadPrefix':When resolving if a given prefix is an interwiki or not. Return true without providing an interwiki to continue interwiki search. $prefix:interwiki prefix we are looking for. & $iwData:output array describing the interwiki with keys iw_url, iw_local, iw_trans and optionally iw_api and iw_wikiid. 'InvalidateEmailComplete':Called after a user 's email has been invalidated successfully. $user:user(object) whose email is being invalidated 'IRCLineURL':When constructing the URL to use in an IRC notification. Callee may modify $url and $query, URL will be constructed as $url . $query & $url:URL to index.php & $query:Query string $rc:RecentChange object that triggered url generation 'IsFileCacheable':Override the result of Article::isFileCacheable()(if true) & $article:article(object) being checked 'IsTrustedProxy':Override the result of IP::isTrustedProxy() & $ip:IP being check & $result:Change this value to override the result of IP::isTrustedProxy() 'IsUploadAllowedFromUrl':Override the result of UploadFromUrl::isAllowedUrl() $url:URL used to upload from & $allowed:Boolean indicating if uploading is allowed for given URL 'isValidEmailAddr':Override the result of Sanitizer::validateEmail(), for instance to return false if the domain name doesn 't match your organization. $addr:The e-mail address entered by the user & $result:Set this and return false to override the internal checks 'isValidPassword':Override the result of User::isValidPassword() $password:The password entered by the user & $result:Set this and return false to override the internal checks $user:User the password is being validated for 'Language::getMessagesFileName':$code:The language code or the language we 're looking for a messages file for & $file:The messages file path, you can override this to change the location. 'LanguageGetNamespaces':Provide custom ordering for namespaces or remove namespaces. Do not use this hook to add namespaces. Use CanonicalNamespaces for that. & $namespaces:Array of namespaces indexed by their numbers 'LanguageGetTranslatedLanguageNames':Provide translated language names. & $names:array of language code=> language name $code:language of the preferred translations 'LanguageLinks':Manipulate a page 's language links. This is called in various places to allow extensions to define the effective language links for a page. $title:The page 's Title. & $links:Array with elements of the form "language:title" in the order that they will be output. & $linkFlags:Associative array mapping prefixed links to arrays of flags. Currently unused, but planned to provide support for marking individual language links in the UI, e.g. for featured articles. 'LanguageSelector':Hook to change the language selector available on a page. $out:The output page. $cssClassName:CSS class name of the language selector. 'LinkBegin':DEPRECATED since 1.28! Use HtmlPageLinkRendererBegin instead. Used when generating internal and interwiki links in Linker::link(), before processing starts. Return false to skip default processing and return $ret. See documentation for Linker::link() for details on the expected meanings of parameters. $skin:the Skin object $target:the Title that the link is pointing to & $html:the contents that the< a > tag should have(raw HTML) $result
Definition: hooks.txt:1970
static singleton(array $options)
__construct(array $options, $id)
int $serializer
Serializer to use (Redis::SERIALIZER_*)
const SERVER_DOWN_TTL
integer; seconds to cache servers as "down".
__destruct()
Make sure connections are closed for sanity.
null means default in associative array with keys and values unescaped Should be merged with default with a value of false meaning to suppress the attribute in associative array with keys and values unescaped & $options
Definition: hooks.txt:1972
this hook is for auditing only or null if authentication failed before getting that far or null if we can t even determine that When $user is not null
Definition: hooks.txt:767
string $readTimeout
Read timeout in seconds.
resetTimeout(Redis $conn, $timeout=null)
Adjust or reset the connection handle read timeout value.
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
Definition: distributors.txt:9
Helper class to manage Redis connections.
closeExcessIdleConections()
Close any extra idle connections if there are more than the limit.
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
Helper class to handle automatically marking connectons as reusable (via RAII pattern) ...
isConnIdentical(Redis $conn)
getConnection( $server, LoggerInterface $logger=null)
Get a connection to a redis server.
setLogger(LoggerInterface $logger)
static array $instances
(pool ID => RedisConnectionPool)
int $idlePoolSize
Current idle pool size.