MediaWiki  master
FileCacheBase.php
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1 <?php
29 abstract class FileCacheBase {
30  protected $mKey;
31  protected $mType = 'object';
32  protected $mExt = 'cache';
33  protected $mFilePath;
34  protected $mUseGzip;
35  /* lazy loaded */
36  protected $mCached;
37 
38  /* @todo configurable? */
39  const MISS_FACTOR = 15; // log 1 every MISS_FACTOR cache misses
40  const MISS_TTL_SEC = 3600; // how many seconds ago is "recent"
41 
42  protected function __construct() {
43  global $wgUseGzip;
44 
45  $this->mUseGzip = (bool)$wgUseGzip;
46  }
47 
52  final protected function baseCacheDirectory() {
53  global $wgFileCacheDirectory;
54 
55  return $wgFileCacheDirectory;
56  }
57 
62  abstract protected function cacheDirectory();
63 
68  protected function cachePath() {
69  if ( $this->mFilePath !== null ) {
70  return $this->mFilePath;
71  }
72 
73  $dir = $this->cacheDirectory();
74  # Build directories (methods include the trailing "/")
75  $subDirs = $this->typeSubdirectory() . $this->hashSubdirectory();
76  # Avoid extension confusion
77  $key = str_replace( '.', '%2E', urlencode( $this->mKey ) );
78  # Build the full file path
79  $this->mFilePath = "{$dir}/{$subDirs}{$key}.{$this->mExt}";
80  if ( $this->useGzip() ) {
81  $this->mFilePath .= '.gz';
82  }
83 
84  return $this->mFilePath;
85  }
86 
91  public function isCached() {
92  if ( $this->mCached === null ) {
93  $this->mCached = file_exists( $this->cachePath() );
94  }
95 
96  return $this->mCached;
97  }
98 
103  public function cacheTimestamp() {
104  $timestamp = filemtime( $this->cachePath() );
105 
106  return ( $timestamp !== false )
107  ? wfTimestamp( TS_MW, $timestamp )
108  : false;
109  }
110 
117  public function isCacheGood( $timestamp = '' ) {
118  global $wgCacheEpoch;
119 
120  if ( !$this->isCached() ) {
121  return false;
122  }
123 
124  $cachetime = $this->cacheTimestamp();
125  $good = ( $timestamp <= $cachetime && $wgCacheEpoch <= $cachetime );
126  wfDebug( __METHOD__ .
127  ": cachetime $cachetime, touched '{$timestamp}' epoch {$wgCacheEpoch}, good $good\n" );
128 
129  return $good;
130  }
131 
136  protected function useGzip() {
137  return $this->mUseGzip;
138  }
139 
144  public function fetchText() {
145  if ( $this->useGzip() ) {
146  $fh = gzopen( $this->cachePath(), 'rb' );
147 
148  return stream_get_contents( $fh );
149  } else {
150  return file_get_contents( $this->cachePath() );
151  }
152  }
153 
159  public function saveText( $text ) {
160  if ( $this->useGzip() ) {
161  $text = gzencode( $text );
162  }
163 
164  $this->checkCacheDirs(); // build parent dir
165  if ( !file_put_contents( $this->cachePath(), $text, LOCK_EX ) ) {
166  wfDebug( __METHOD__ . "() failed saving " . $this->cachePath() . "\n" );
167  $this->mCached = null;
168 
169  return false;
170  }
171 
172  $this->mCached = true;
173 
174  return $text;
175  }
176 
181  public function clearCache() {
182  Wikimedia\suppressWarnings();
183  unlink( $this->cachePath() );
184  Wikimedia\restoreWarnings();
185  $this->mCached = false;
186  }
187 
192  protected function checkCacheDirs() {
193  wfMkdirParents( dirname( $this->cachePath() ), null, __METHOD__ );
194  }
195 
203  protected function typeSubdirectory() {
204  return $this->mType . '/';
205  }
206 
212  protected function hashSubdirectory() {
213  global $wgFileCacheDepth;
214 
215  $subdir = '';
216  if ( $wgFileCacheDepth > 0 ) {
217  $hash = md5( $this->mKey );
218  for ( $i = 1; $i <= $wgFileCacheDepth; $i++ ) {
219  $subdir .= substr( $hash, 0, $i ) . '/';
220  }
221  }
222 
223  return $subdir;
224  }
225 
231  public function incrMissesRecent( WebRequest $request ) {
232  if ( mt_rand( 0, self::MISS_FACTOR - 1 ) == 0 ) {
234  # Get a large IP range that should include the user even if that
235  # person's IP address changes
236  $ip = $request->getIP();
237  if ( !IP::isValid( $ip ) ) {
238  return;
239  }
240  $ip = IP::isIPv6( $ip )
241  ? IP::sanitizeRange( "$ip/32" )
242  : IP::sanitizeRange( "$ip/16" );
243 
244  # Bail out if a request already came from this range...
245  $key = $cache->makeKey( static::class, 'attempt', $this->mType, $this->mKey, $ip );
246  if ( $cache->get( $key ) ) {
247  return; // possibly the same user
248  }
249  $cache->set( $key, 1, self::MISS_TTL_SEC );
250 
251  # Increment the number of cache misses...
252  $key = $this->cacheMissKey( $cache );
253  if ( $cache->get( $key ) === false ) {
254  $cache->set( $key, 1, self::MISS_TTL_SEC );
255  } else {
256  $cache->incr( $key );
257  }
258  }
259  }
260 
265  public function getMissesRecent() {
267 
268  return self::MISS_FACTOR * $cache->get( $this->cacheMissKey( $cache ) );
269  }
270 
275  protected function cacheMissKey( BagOStuff $cache ) {
276  return $cache->makeKey( static::class, 'misses', $this->mType, $this->mKey );
277  }
278 }
isCacheGood( $timestamp='')
Check if up to date cache file exists.
getIP()
Work out the IP address based on various globals For trusted proxies, use the XFF client IP (first of...
processing should stop and the error should be shown to the user * false
Definition: hooks.txt:187
incrMissesRecent(WebRequest $request)
Roughly increments the cache misses in the last hour by unique visitors.
baseCacheDirectory()
Get the base file cache directory.
static getLocalClusterInstance()
Get the main cluster-local cache object.
makeKey( $class, $component=null)
Make a cache key, scoped to this instance&#39;s keyspace.
Definition: BagOStuff.php:977
$wgFileCacheDepth
Depth of the subdirectory hierarchy to be created under $wgFileCacheDirectory.
static sanitizeRange( $range)
Gets rid of unneeded numbers in quad-dotted/octet IP strings For example, 127.111.113.151/24 -> 127.111.113.0/24.
Definition: IP.php:712
cacheTimestamp()
Get the last-modified timestamp of the cache file.
isCached()
Check if the cache file exists.
wfTimestamp( $outputtype=TS_UNIX, $ts=0)
Get a timestamp string in one of various formats.
typeSubdirectory()
Get the cache type subdirectory (with trailing slash) An extending class could use that method to alt...
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
Base class for data storage in the file system.
static isValid( $ip)
Validate an IP address.
Definition: IP.php:111
$cache
Definition: mcc.php:33
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:780
$wgUseGzip
When using the file cache, we can store the cached HTML gzipped to save disk space.
cachePath()
Get the path to the cache file.
hashSubdirectory()
Return relative multi-level hash subdirectory (with trailing slash) or the empty string if not $wgFil...
cacheDirectory()
Get the base cache directory (not specific to this file)
fetchText()
Get the uncompressed text from the cache.
getMissesRecent()
Roughly gets the cache misses in the last hour by unique visitors.
clearCache()
Clear the cache for this page.
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
static isIPv6( $ip)
Given a string, determine if it as valid IP in IPv6 only.
Definition: IP.php:88
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:52
wfMkdirParents( $dir, $mode=null, $caller=null)
Make directory, and make all parent directories if they don&#39;t exist.
useGzip()
Check if the cache is gzipped.
checkCacheDirs()
Create parent directors of $this->cachePath()
cacheMissKey(BagOStuff $cache)
$wgCacheEpoch
Set this to current time to invalidate all prior cached pages.
do that in ParserLimitReportFormat instead use this to modify the parameters of the image all existing parser cache entries will be invalid To avoid you ll need to handle that somehow(e.g. with the RejectParserCacheValue hook) because MediaWiki won 't do it for you. & $defaults also a ContextSource after deleting those rows but within the same transaction you ll probably need to make sure the header is varied on $request
Definition: hooks.txt:2633
$wgFileCacheDirectory
Directory where the cached page will be saved.
saveText( $text)
Save and compress text to the cache.