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CommentStore.php
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1 <?php
25 
31 class CommentStore {
32 
38 
44  const MAX_COMMENT_LENGTH = 65535;
45 
51  const MAX_DATA_LENGTH = 65535;
52 
63  protected $tempTables = [
64  'rev_comment' => [
65  'table' => 'revision_comment_temp',
66  'pk' => 'revcomment_rev',
67  'field' => 'revcomment_comment_id',
68  'joinPK' => 'rev_id',
69  'stage' => MIGRATION_OLD,
70  'deprecatedIn' => null,
71  ],
72  'img_description' => [
73  'stage' => MIGRATION_NEW,
74  'deprecatedIn' => '1.32',
75  ],
76  ];
77 
83  protected $key = null;
84 
90  protected $stage;
91 
93  protected $joinCache = [];
94 
96  protected $lang;
97 
104  public function __construct( Language $lang, $migrationStage ) {
105  $this->stage = $migrationStage;
106  $this->lang = $lang;
107  }
108 
116  public static function newKey( $key ) {
117  wfDeprecated( __METHOD__, '1.31' );
118  $store = new CommentStore(
119  MediaWikiServices::getInstance()->getContentLanguage(), MIGRATION_NEW
120  );
121  $store->key = $key;
122  return $store;
123  }
124 
130  public static function getStore() {
131  return MediaWikiServices::getInstance()->getCommentStore();
132  }
133 
140  private function getKey( $methodKey = null ) {
141  $key = $this->key ?? $methodKey;
142  if ( $key === null ) {
143  // @codeCoverageIgnoreStart
144  throw new InvalidArgumentException( '$key should not be null' );
145  // @codeCoverageIgnoreEnd
146  }
147  return $key;
148  }
149 
166  public function getFields( $key = null ) {
167  $key = $this->getKey( $key );
168  $fields = [];
169  if ( $this->stage === MIGRATION_OLD ) {
170  $fields["{$key}_text"] = $key;
171  $fields["{$key}_data"] = 'NULL';
172  $fields["{$key}_cid"] = 'NULL';
173  } else {
174  if ( $this->stage < MIGRATION_NEW ) {
175  $fields["{$key}_old"] = $key;
176  }
177 
178  $tempTableStage = isset( $this->tempTables[$key] )
179  ? $this->tempTables[$key]['stage'] : MIGRATION_NEW;
180  if ( $tempTableStage < MIGRATION_NEW ) {
181  $fields["{$key}_pk"] = $this->tempTables[$key]['joinPK'];
182  }
183  if ( $tempTableStage > MIGRATION_OLD ) {
184  $fields["{$key}_id"] = "{$key}_id";
185  }
186  }
187  return $fields;
188  }
189 
207  public function getJoin( $key = null ) {
208  $key = $this->getKey( $key );
209  if ( !array_key_exists( $key, $this->joinCache ) ) {
210  $tables = [];
211  $fields = [];
212  $joins = [];
213 
214  if ( $this->stage === MIGRATION_OLD ) {
215  $fields["{$key}_text"] = $key;
216  $fields["{$key}_data"] = 'NULL';
217  $fields["{$key}_cid"] = 'NULL';
218  } else {
219  $join = $this->stage === MIGRATION_NEW ? 'JOIN' : 'LEFT JOIN';
220 
221  $tempTableStage = isset( $this->tempTables[$key] )
222  ? $this->tempTables[$key]['stage'] : MIGRATION_NEW;
223  if ( $tempTableStage < MIGRATION_NEW ) {
224  $t = $this->tempTables[$key];
225  $alias = "temp_$key";
226  $tables[$alias] = $t['table'];
227  $joins[$alias] = [ $join, "{$alias}.{$t['pk']} = {$t['joinPK']}" ];
228  if ( $tempTableStage === MIGRATION_OLD ) {
229  $joinField = "{$alias}.{$t['field']}";
230  } else {
231  // Nothing hits this code path for now, but will in the future when we set
232  // $this->tempTables['rev_comment']['stage'] to MIGRATION_WRITE_NEW while
233  // merging revision_comment_temp into revision.
234  // @codeCoverageIgnoreStart
235  $joins[$alias][0] = 'LEFT JOIN';
236  $joinField = "(CASE WHEN {$key}_id != 0 THEN {$key}_id ELSE {$alias}.{$t['field']} END)";
237  throw new LogicException( 'Nothing should reach this code path at this time' );
238  // @codeCoverageIgnoreEnd
239  }
240  } else {
241  $joinField = "{$key}_id";
242  }
243 
244  $alias = "comment_$key";
245  $tables[$alias] = 'comment';
246  $joins[$alias] = [ $join, "{$alias}.comment_id = {$joinField}" ];
247 
248  if ( $this->stage === MIGRATION_NEW ) {
249  $fields["{$key}_text"] = "{$alias}.comment_text";
250  } else {
251  $fields["{$key}_text"] = "COALESCE( {$alias}.comment_text, $key )";
252  }
253  $fields["{$key}_data"] = "{$alias}.comment_data";
254  $fields["{$key}_cid"] = "{$alias}.comment_id";
255  }
256 
257  $this->joinCache[$key] = [
258  'tables' => $tables,
259  'fields' => $fields,
260  'joins' => $joins,
261  ];
262  }
263 
264  return $this->joinCache[$key];
265  }
266 
279  private function getCommentInternal( IDatabase $db = null, $key, $row, $fallback = false ) {
280  $row = (array)$row;
281  if ( array_key_exists( "{$key}_text", $row ) && array_key_exists( "{$key}_data", $row ) ) {
282  $cid = $row["{$key}_cid"] ?? null;
283  $text = $row["{$key}_text"];
284  $data = $row["{$key}_data"];
285  } elseif ( $this->stage === MIGRATION_OLD ) {
286  $cid = null;
287  if ( $fallback && isset( $row[$key] ) ) {
288  wfLogWarning( "Using deprecated fallback handling for comment $key" );
289  $text = $row[$key];
290  } else {
291  wfLogWarning( "Missing {$key}_text and {$key}_data fields in row with MIGRATION_OLD" );
292  $text = '';
293  }
294  $data = null;
295  } else {
296  $tempTableStage = isset( $this->tempTables[$key] )
297  ? $this->tempTables[$key]['stage'] : MIGRATION_NEW;
298  $row2 = null;
299  if ( $tempTableStage > MIGRATION_OLD && array_key_exists( "{$key}_id", $row ) ) {
300  if ( !$db ) {
301  throw new InvalidArgumentException(
302  "\$row does not contain fields needed for comment $key and getComment(), but "
303  . "does have fields for getCommentLegacy()"
304  );
305  }
306  $id = $row["{$key}_id"];
307  $row2 = $db->selectRow(
308  'comment',
309  [ 'comment_id', 'comment_text', 'comment_data' ],
310  [ 'comment_id' => $id ],
311  __METHOD__
312  );
313  }
314  if ( !$row2 && $tempTableStage < MIGRATION_NEW && array_key_exists( "{$key}_pk", $row ) ) {
315  if ( !$db ) {
316  throw new InvalidArgumentException(
317  "\$row does not contain fields needed for comment $key and getComment(), but "
318  . "does have fields for getCommentLegacy()"
319  );
320  }
321  $t = $this->tempTables[$key];
322  $id = $row["{$key}_pk"];
323  $row2 = $db->selectRow(
324  [ $t['table'], 'comment' ],
325  [ 'comment_id', 'comment_text', 'comment_data' ],
326  [ $t['pk'] => $id ],
327  __METHOD__,
328  [],
329  [ 'comment' => [ 'JOIN', [ "comment_id = {$t['field']}" ] ] ]
330  );
331  }
332  if ( $row2 === null && $fallback && isset( $row[$key] ) ) {
333  wfLogWarning( "Using deprecated fallback handling for comment $key" );
334  $row2 = (object)[ 'comment_text' => $row[$key], 'comment_data' => null ];
335  }
336  if ( $row2 === null ) {
337  throw new InvalidArgumentException( "\$row does not contain fields needed for comment $key" );
338  }
339 
340  if ( $row2 ) {
341  $cid = $row2->comment_id;
342  $text = $row2->comment_text;
343  $data = $row2->comment_data;
344  } elseif ( $this->stage < MIGRATION_NEW && array_key_exists( "{$key}_old", $row ) ) {
345  $cid = null;
346  $text = $row["{$key}_old"];
347  $data = null;
348  } else {
349  // @codeCoverageIgnoreStart
350  wfLogWarning( "Missing comment row for $key, id=$id" );
351  $cid = null;
352  $text = '';
353  $data = null;
354  // @codeCoverageIgnoreEnd
355  }
356  }
357 
358  $msg = null;
359  if ( $data !== null ) {
360  $data = FormatJson::decode( $data, true );
361  if ( !is_array( $data ) ) {
362  // @codeCoverageIgnoreStart
363  wfLogWarning( "Invalid JSON object in comment: $data" );
364  $data = null;
365  // @codeCoverageIgnoreEnd
366  } else {
367  if ( isset( $data['_message'] ) ) {
368  $msg = self::decodeMessage( $data['_message'] )
369  ->setInterfaceMessageFlag( true );
370  }
371  if ( !empty( $data['_null'] ) ) {
372  $data = null;
373  } else {
374  foreach ( $data as $k => $v ) {
375  if ( substr( $k, 0, 1 ) === '_' ) {
376  unset( $data[$k] );
377  }
378  }
379  }
380  }
381  }
382 
383  return new CommentStoreComment( $cid, $text, $msg, $data );
384  }
385 
402  public function getComment( $key, $row = null, $fallback = false ) {
403  // Compat for method sig change in 1.31 (introduction of $key)
404  if ( $this->key !== null ) {
405  $fallback = $row;
406  $row = $key;
407  $key = $this->getKey();
408  }
409  if ( $row === null ) {
410  // @codeCoverageIgnoreStart
411  throw new InvalidArgumentException( '$row must not be null' );
412  // @codeCoverageIgnoreEnd
413  }
414  return $this->getCommentInternal( null, $key, $row, $fallback );
415  }
416 
436  public function getCommentLegacy( IDatabase $db, $key, $row = null, $fallback = false ) {
437  // Compat for method sig change in 1.31 (introduction of $key)
438  if ( $this->key !== null ) {
439  $fallback = $row;
440  $row = $key;
441  $key = $this->getKey();
442  }
443  if ( $row === null ) {
444  // @codeCoverageIgnoreStart
445  throw new InvalidArgumentException( '$row must not be null' );
446  // @codeCoverageIgnoreEnd
447  }
448  return $this->getCommentInternal( $db, $key, $row, $fallback );
449  }
450 
471  public function createComment( IDatabase $dbw, $comment, array $data = null ) {
472  $comment = CommentStoreComment::newUnsavedComment( $comment, $data );
473 
474  # Truncate comment in a Unicode-sensitive manner
475  $comment->text = $this->lang->truncateForVisual( $comment->text, self::COMMENT_CHARACTER_LIMIT );
476 
477  if ( $this->stage > MIGRATION_OLD && !$comment->id ) {
478  $dbData = $comment->data;
479  if ( !$comment->message instanceof RawMessage ) {
480  if ( $dbData === null ) {
481  $dbData = [ '_null' => true ];
482  }
483  $dbData['_message'] = self::encodeMessage( $comment->message );
484  }
485  if ( $dbData !== null ) {
486  $dbData = FormatJson::encode( (object)$dbData, false, FormatJson::ALL_OK );
487  $len = strlen( $dbData );
488  if ( $len > self::MAX_DATA_LENGTH ) {
489  $max = self::MAX_DATA_LENGTH;
490  throw new OverflowException( "Comment data is too long ($len bytes, maximum is $max)" );
491  }
492  }
493 
494  $hash = self::hash( $comment->text, $dbData );
495  $comment->id = $dbw->selectField(
496  'comment',
497  'comment_id',
498  [
499  'comment_hash' => $hash,
500  'comment_text' => $comment->text,
501  'comment_data' => $dbData,
502  ],
503  __METHOD__
504  );
505  if ( !$comment->id ) {
506  $dbw->insert(
507  'comment',
508  [
509  'comment_hash' => $hash,
510  'comment_text' => $comment->text,
511  'comment_data' => $dbData,
512  ],
513  __METHOD__
514  );
515  $comment->id = $dbw->insertId();
516  }
517  }
518 
519  return $comment;
520  }
521 
531  private function insertInternal( IDatabase $dbw, $key, $comment, $data ) {
532  $fields = [];
533  $callback = null;
534 
535  $comment = $this->createComment( $dbw, $comment, $data );
536 
537  if ( $this->stage <= MIGRATION_WRITE_BOTH ) {
538  $fields[$key] = $this->lang->truncateForDatabase( $comment->text, 255 );
539  }
540 
541  if ( $this->stage >= MIGRATION_WRITE_BOTH ) {
542  $tempTableStage = isset( $this->tempTables[$key] )
543  ? $this->tempTables[$key]['stage'] : MIGRATION_NEW;
544  if ( $tempTableStage <= MIGRATION_WRITE_BOTH ) {
545  $t = $this->tempTables[$key];
546  $func = __METHOD__;
547  $commentId = $comment->id;
548  $callback = function ( $id ) use ( $dbw, $commentId, $t, $func ) {
549  $dbw->insert(
550  $t['table'],
551  [
552  $t['pk'] => $id,
553  $t['field'] => $commentId,
554  ],
555  $func
556  );
557  };
558  }
559  if ( $tempTableStage >= MIGRATION_WRITE_BOTH ) {
560  $fields["{$key}_id"] = $comment->id;
561  }
562  }
563 
564  return [ $fields, $callback ];
565  }
566 
582  public function insert( IDatabase $dbw, $key, $comment = null, $data = null ) {
583  // Compat for method sig change in 1.31 (introduction of $key)
584  if ( $this->key !== null ) {
585  $data = $comment;
586  $comment = $key;
587  $key = $this->key;
588  }
589  if ( $comment === null ) {
590  // @codeCoverageIgnoreStart
591  throw new InvalidArgumentException( '$comment can not be null' );
592  // @codeCoverageIgnoreEnd
593  }
594 
595  $tempTableStage = isset( $this->tempTables[$key] )
596  ? $this->tempTables[$key]['stage'] : MIGRATION_NEW;
597  if ( $tempTableStage < MIGRATION_WRITE_NEW ) {
598  throw new InvalidArgumentException( "Must use insertWithTempTable() for $key" );
599  }
600 
601  list( $fields ) = $this->insertInternal( $dbw, $key, $comment, $data );
602  return $fields;
603  }
604 
626  public function insertWithTempTable( IDatabase $dbw, $key, $comment = null, $data = null ) {
627  // Compat for method sig change in 1.31 (introduction of $key)
628  if ( $this->key !== null ) {
629  $data = $comment;
630  $comment = $key;
631  $key = $this->getKey();
632  }
633  if ( $comment === null ) {
634  // @codeCoverageIgnoreStart
635  throw new InvalidArgumentException( '$comment can not be null' );
636  // @codeCoverageIgnoreEnd
637  }
638 
639  if ( !isset( $this->tempTables[$key] ) ) {
640  throw new InvalidArgumentException( "Must use insert() for $key" );
641  } elseif ( isset( $this->tempTables[$key]['deprecatedIn'] ) ) {
642  wfDeprecated( __METHOD__ . " for $key", $this->tempTables[$key]['deprecatedIn'] );
643  }
644 
645  list( $fields, $callback ) = $this->insertInternal( $dbw, $key, $comment, $data );
646  if ( !$callback ) {
647  $callback = function () {
648  // Do nothing.
649  };
650  }
651  return [ $fields, $callback ];
652  }
653 
659  protected static function encodeMessage( Message $msg ) {
660  $key = count( $msg->getKeysToTry() ) > 1 ? $msg->getKeysToTry() : $msg->getKey();
661  $params = $msg->getParams();
662  foreach ( $params as &$param ) {
663  if ( $param instanceof Message ) {
664  $param = [
665  'message' => self::encodeMessage( $param )
666  ];
667  }
668  }
669  array_unshift( $params, $key );
670  return $params;
671  }
672 
678  protected static function decodeMessage( $data ) {
679  $key = array_shift( $data );
680  foreach ( $data as &$param ) {
681  if ( is_object( $param ) ) {
682  $param = (array)$param;
683  }
684  if ( is_array( $param ) && count( $param ) === 1 && isset( $param['message'] ) ) {
685  $param = self::decodeMessage( $param['message'] );
686  }
687  }
688  return new Message( $key, $data );
689  }
690 
697  public static function hash( $text, $data ) {
698  $hash = crc32( $text ) ^ crc32( (string)$data );
699 
700  // 64-bit PHP returns an unsigned CRC, change it to signed for
701  // insertion into the database.
702  if ( $hash >= 0x80000000 ) {
703  $hash |= -1 << 32;
704  }
705 
706  return $hash;
707  }
708 
709 }
The wiki should then use memcached to cache various data To use multiple just add more items to the array To increase the weight of a make its entry a array("192.168.0.1:11211", 2))
getKeysToTry()
Definition: Message.php:341
getKey()
Returns the message key.
Definition: Message.php:356
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
static encodeMessage(Message $msg)
Encode a Message as a PHP data structure.
static newKey( $key)
Static constructor for easier chaining.
insertWithTempTable(IDatabase $dbw, $key, $comment=null, $data=null)
Insert a comment in a temporary table in preparation for a row that references it.
array string null $key
selectField( $table, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
A SELECT wrapper which returns a single field from a single result row.
const MIGRATION_WRITE_NEW
Definition: Defines.php:313
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
insert( $table, $a, $fname=__METHOD__, $options=[])
INSERT wrapper, inserts an array into a table.
globals will be eliminated from MediaWiki replaced by an application object which would be passed to constructors Whether that would be an convenient solution remains to be but certainly PHP makes such object oriented programming models easier than they were in previous versions For the time being MediaWiki programmers will have to work in an environment with some global context At the time of globals were initialised on startup by MediaWiki of these were configuration which are documented in DefaultSettings php There is no comprehensive documentation for the remaining however some of the most important ones are listed below They are typically initialised either in index php or in Setup php $wgTitle Title object created from the request URL $wgOut OutputPage object for HTTP response $wgUser User object for the user associated with the current request $wgLang Language object selected by user preferences $wgContLang Language object associated with the wiki being viewed $wgParser Parser object Parser extensions register their hooks here $wgRequest WebRequest object
Definition: globals.txt:25
getCommentInternal(IDatabase $db=null, $key, $row, $fallback=false)
Extract the comment from a row.
const ALL_OK
Skip escaping as many characters as reasonably possible.
Definition: FormatJson.php:55
static hash( $text, $data)
Hashing function for comment storage.
const MAX_DATA_LENGTH
Maximum length of serialized data in bytes.
const MIGRATION_WRITE_BOTH
Definition: Defines.php:312
either a unescaped string or a HtmlArmor object after in associative array form externallinks including delete and has completed for all link tables whether this was an auto creation use $formDescriptor instead default is conds Array Extra conditions for the No matching items in log is displayed if loglist is empty msgKey Array If you want a nice box with a set this to the key of the message First element is the message key
Definition: hooks.txt:2151
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 MediaWikiServices
Definition: injection.txt:23
static encode( $value, $pretty=false, $escaping=0)
Returns the JSON representation of a value.
Definition: FormatJson.php:115
wfLogWarning( $msg, $callerOffset=1, $level=E_USER_WARNING)
Send a warning as a PHP error and the debug log.
insertId()
Get the inserted value of an auto-increment row.
const COMMENT_CHARACTER_LIMIT
Maximum length of a comment in UTF-8 characters.
createComment(IDatabase $dbw, $comment, array $data=null)
Create a new CommentStoreComment, inserting it into the database if necessary.
static newUnsavedComment( $comment, array $data=null)
Create a new, unsaved CommentStoreComment.
this hook is for auditing only RecentChangesLinked and Watchlist Do not use this to implement individual filters if they are compatible with the ChangesListFilter and ChangesListFilterGroup structure use sub classes of those in conjunction with the ChangesListSpecialPageStructuredFilters hook This hook can be used to implement filters that do not implement that or custom behavior that is not an individual filter e g Watchlist & $tables
Definition: hooks.txt:979
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 noclasses just before the function returns a value If you return true
Definition: hooks.txt:1982
getParams()
Returns the message parameters.
Definition: Message.php:367
getFields( $key=null)
Get SELECT fields for the comment key.
getJoin( $key=null)
Get SELECT fields and joins for the comment key.
const MIGRATION_OLD
Definition: Defines.php:311
static decode( $value, $assoc=false)
Decodes a JSON string.
Definition: FormatJson.php:174
Language $lang
Language to use for comment truncation.
$params
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
const MAX_COMMENT_LENGTH
Maximum length of a comment in bytes.
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
insert(IDatabase $dbw, $key, $comment=null, $data=null)
Insert a comment in preparation for a row that references it.
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
getCommentLegacy(IDatabase $db, $key, $row=null, $fallback=false)
Extract the comment from a row, with legacy lookups.
$fallback
Definition: MessagesAb.php:11
static getStore()
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:38
Variant of the Message class.
Definition: RawMessage.php:34
wfDeprecated( $function, $version=false, $component=false, $callerOffset=2)
Throws a warning that $function is deprecated.
getComment( $key, $row=null, $fallback=false)
Extract the comment from a row.
array [] $joinCache
Cache for self::getJoin()
int $stage
One of the MIGRATION_* constants.
array $tempTables
Define fields that use temporary tables for transitional purposes Keys are &#39;$key&#39;, values are arrays with these possible fields:
getKey( $methodKey=null)
Compat method allowing use of self::newKey until removed.
__construct(Language $lang, $migrationStage)
const MIGRATION_NEW
Definition: Defines.php:314
static decodeMessage( $data)
Decode a message that was encoded by self::encodeMessage()
insertInternal(IDatabase $dbw, $key, $comment, $data)
Implementation for self::insert() and self::insertWithTempTable()