mediawiki-extensions-AbuseF.../includes/Variables/LazyVariableComputer.php
thiemowmde 84058c3d96 Make use of the ??= operator and such where it makes sense
We can avoid a bit of code duplication and move code closer together
when it belongs together.

Change-Id: Iffca7e4abfbf03d4663ee909220057bcbd54da75
2023-06-12 10:27:03 +02:00

518 lines
16 KiB
PHP

<?php
namespace MediaWiki\Extension\AbuseFilter\Variables;
use ContentHandler;
use Diff;
use Language;
use MediaWiki\Extension\AbuseFilter\Hooks\AbuseFilterHookRunner;
use MediaWiki\Extension\AbuseFilter\Parser\AFPData;
use MediaWiki\Extension\AbuseFilter\TextExtractor;
use MediaWiki\ExternalLinks\ExternalLinksLookup;
use MediaWiki\ExternalLinks\LinkFilter;
use MediaWiki\Permissions\PermissionManager;
use MediaWiki\Permissions\RestrictionStore;
use MediaWiki\Revision\RevisionLookup;
use MediaWiki\Revision\RevisionRecord;
use MediaWiki\Revision\RevisionStore;
use MediaWiki\Revision\SlotRecord;
use MediaWiki\User\UserEditTracker;
use MediaWiki\User\UserGroupManager;
use MediaWiki\User\UserIdentity;
use Parser;
use ParserOptions;
use Psr\Log\LoggerInterface;
use stdClass;
use StringUtils;
use TextContent;
use Title;
use UnexpectedValueException;
use UnifiedDiffFormatter;
use User;
use WANObjectCache;
use Wikimedia\Rdbms\Database;
use Wikimedia\Rdbms\LBFactory;
use WikiPage;
/**
* Service used to compute lazy-loaded variable.
* @internal
*/
class LazyVariableComputer {
public const SERVICE_NAME = 'AbuseFilterLazyVariableComputer';
/**
* @var float The amount of time to subtract from profiling
* @todo This is a hack
*/
public static $profilingExtraTime = 0;
/** @var TextExtractor */
private $textExtractor;
/** @var AbuseFilterHookRunner */
private $hookRunner;
/** @var LoggerInterface */
private $logger;
/** @var LBFactory */
private $lbFactory;
/** @var WANObjectCache */
private $wanCache;
/** @var RevisionLookup */
private $revisionLookup;
/** @var RevisionStore */
private $revisionStore;
/** @var Language */
private $contentLanguage;
/** @var Parser */
private $parser;
/** @var UserEditTracker */
private $userEditTracker;
/** @var UserGroupManager */
private $userGroupManager;
/** @var PermissionManager */
private $permissionManager;
/** @var RestrictionStore */
private $restrictionStore;
/** @var string */
private $wikiID;
/**
* @param TextExtractor $textExtractor
* @param AbuseFilterHookRunner $hookRunner
* @param LoggerInterface $logger
* @param LBFactory $lbFactory
* @param WANObjectCache $wanCache
* @param RevisionLookup $revisionLookup
* @param RevisionStore $revisionStore
* @param Language $contentLanguage
* @param Parser $parser
* @param UserEditTracker $userEditTracker
* @param UserGroupManager $userGroupManager
* @param PermissionManager $permissionManager
* @param RestrictionStore $restrictionStore
* @param string $wikiID
*/
public function __construct(
TextExtractor $textExtractor,
AbuseFilterHookRunner $hookRunner,
LoggerInterface $logger,
LBFactory $lbFactory,
WANObjectCache $wanCache,
RevisionLookup $revisionLookup,
RevisionStore $revisionStore,
Language $contentLanguage,
Parser $parser,
UserEditTracker $userEditTracker,
UserGroupManager $userGroupManager,
PermissionManager $permissionManager,
RestrictionStore $restrictionStore,
string $wikiID
) {
$this->textExtractor = $textExtractor;
$this->hookRunner = $hookRunner;
$this->logger = $logger;
$this->lbFactory = $lbFactory;
$this->wanCache = $wanCache;
$this->revisionLookup = $revisionLookup;
$this->revisionStore = $revisionStore;
$this->contentLanguage = $contentLanguage;
$this->parser = $parser;
$this->userEditTracker = $userEditTracker;
$this->userGroupManager = $userGroupManager;
$this->permissionManager = $permissionManager;
$this->restrictionStore = $restrictionStore;
$this->wikiID = $wikiID;
}
/**
* XXX: $getVarCB is a hack to hide the cyclic dependency with VariablesManager. See T261069 for possible
* solutions. This might also be merged into VariablesManager, but it would bring a ton of dependencies.
* @todo Should we remove $vars parameter (check hooks)?
*
* @param LazyLoadedVariable $var
* @param VariableHolder $vars
* @param callable $getVarCB
* @phan-param callable(string $name):AFPData $getVarCB
* @return AFPData
*/
public function compute( LazyLoadedVariable $var, VariableHolder $vars, callable $getVarCB ) {
$parameters = $var->getParameters();
$varMethod = $var->getMethod();
$result = null;
if ( !$this->hookRunner->onAbuseFilter_interceptVariable(
$varMethod,
$vars,
$parameters,
$result
) ) {
return $result instanceof AFPData
? $result : AFPData::newFromPHPVar( $result );
}
switch ( $varMethod ) {
case 'diff':
$text1Var = $parameters['oldtext-var'];
$text2Var = $parameters['newtext-var'];
$text1 = $getVarCB( $text1Var )->toString();
$text2 = $getVarCB( $text2Var )->toString();
// T74329: if there's no text, don't return an array with the empty string
$text1 = $text1 === '' ? [] : explode( "\n", $text1 );
$text2 = $text2 === '' ? [] : explode( "\n", $text2 );
$diffs = new Diff( $text1, $text2 );
$format = new UnifiedDiffFormatter();
$result = $format->format( $diffs );
break;
case 'diff-split':
$diff = $getVarCB( $parameters['diff-var'] )->toString();
$line_prefix = $parameters['line-prefix'];
$diff_lines = explode( "\n", $diff );
$result = [];
foreach ( $diff_lines as $line ) {
if ( ( $line[0] ?? '' ) === $line_prefix ) {
$result[] = substr( $line, 1 );
}
}
break;
case 'links-from-wikitext':
// This should ONLY be used when sharing a parse operation with the edit.
/** @var WikiPage $article */
$article = $parameters['article'];
if ( $article->getContentModel() === CONTENT_MODEL_WIKITEXT ) {
// Shared with the edit, don't count it in profiling
$startTime = microtime( true );
$textVar = $parameters['text-var'];
$new_text = $getVarCB( $textVar )->toString();
$content = ContentHandler::makeContent( $new_text, $article->getTitle() );
$editInfo = $article->prepareContentForEdit(
$content,
null,
$parameters['contextUserIdentity']
);
$result = LinkFilter::getIndexedUrlsNonReversed(
array_keys( $editInfo->output->getExternalLinks() )
);
self::$profilingExtraTime += ( microtime( true ) - $startTime );
break;
}
// Otherwise fall back to database
case 'links-from-wikitext-or-database':
// TODO: use Content object instead, if available!
/** @var WikiPage $article */
$article ??= $parameters['article'];
// this inference is ugly, but the name isn't accessible from here
// and we only want this for debugging
$varName = strpos( $parameters['text-var'], 'old_' ) === 0 ? 'old_links' : 'all_links';
if ( $parameters['forFilter'] ?? false ) {
$this->logger->debug( "Loading $varName from DB" );
$links = $this->getLinksFromDB( $article );
} elseif ( $article->getContentModel() === CONTENT_MODEL_WIKITEXT ) {
$this->logger->debug( "Loading $varName from Parser" );
$textVar = $parameters['text-var'];
$wikitext = $getVarCB( $textVar )->toString();
$editInfo = $this->parseNonEditWikitext(
$wikitext,
$article,
$parameters['contextUserIdentity']
);
$links = LinkFilter::getIndexedUrlsNonReversed(
array_keys( $editInfo->output->getExternalLinks() )
);
} else {
// TODO: Get links from Content object. But we don't have the content object.
// And for non-text content, $wikitext is usually not going to be a valid
// serialization, but rather some dummy text for filtering.
$links = [];
}
$result = $links;
break;
case 'link-diff-added':
case 'link-diff-removed':
$oldLinkVar = $parameters['oldlink-var'];
$newLinkVar = $parameters['newlink-var'];
$oldLinks = $getVarCB( $oldLinkVar )->toNative();
$newLinks = $getVarCB( $newLinkVar )->toNative();
if ( $varMethod === 'link-diff-added' ) {
$result = array_diff( $newLinks, $oldLinks );
}
if ( $varMethod === 'link-diff-removed' ) {
$result = array_diff( $oldLinks, $newLinks );
}
break;
case 'parse-wikitext':
// Should ONLY be used when sharing a parse operation with the edit.
// TODO: use Content object instead, if available!
/* @var WikiPage $article */
$article = $parameters['article'];
if ( $article->getContentModel() === CONTENT_MODEL_WIKITEXT ) {
// Shared with the edit, don't count it in profiling
$startTime = microtime( true );
$textVar = $parameters['wikitext-var'];
$new_text = $getVarCB( $textVar )->toString();
$content = ContentHandler::makeContent( $new_text, $article->getTitle() );
$editInfo = $article->prepareContentForEdit(
$content,
null,
$parameters['contextUserIdentity']
);
if ( isset( $parameters['pst'] ) && $parameters['pst'] ) {
$result = $editInfo->pstContent->serialize( $editInfo->format );
} else {
// Note: as of core change r727361, the PP limit comments (which we don't want to be here)
// are already excluded.
$result = $editInfo->getOutput()->getText();
}
self::$profilingExtraTime += ( microtime( true ) - $startTime );
} else {
$result = '';
}
break;
case 'strip-html':
$htmlVar = $parameters['html-var'];
$html = $getVarCB( $htmlVar )->toString();
$stripped = StringUtils::delimiterReplace( '<', '>', '', $html );
// We strip extra spaces to the right because the stripping above
// could leave a lot of whitespace.
// @fixme Find a better way to do this.
$result = TextContent::normalizeLineEndings( $stripped );
break;
case 'load-recent-authors':
$result = $this->getLastPageAuthors( $parameters['title'] );
break;
case 'load-first-author':
$revision = $this->revisionLookup->getFirstRevision( $parameters['title'] );
if ( $revision ) {
// TODO T233241
$user = $revision->getUser();
$result = $user === null ? '' : $user->getName();
} else {
$result = '';
}
break;
case 'get-page-restrictions':
$action = $parameters['action'];
/** @var Title $title */
$title = $parameters['title'];
$result = $this->restrictionStore->getRestrictions( $title, $action );
break;
case 'user-editcount':
/** @var UserIdentity $userIdentity */
$userIdentity = $parameters['user-identity'];
$result = $this->userEditTracker->getUserEditCount( $userIdentity );
break;
case 'user-emailconfirm':
/** @var User $user */
$user = $parameters['user'];
$result = $user->getEmailAuthenticationTimestamp();
break;
case 'user-groups':
/** @var UserIdentity $userIdentity */
$userIdentity = $parameters['user-identity'];
$result = $this->userGroupManager->getUserEffectiveGroups( $userIdentity );
break;
case 'user-rights':
/** @var UserIdentity $userIdentity */
$userIdentity = $parameters['user-identity'];
$result = $this->permissionManager->getUserPermissions( $userIdentity );
break;
case 'user-block':
// @todo Support partial blocks?
/** @var User $user */
$user = $parameters['user'];
$result = (bool)$user->getBlock();
break;
case 'user-age':
/** @var User $user */
$user = $parameters['user'];
$asOf = $parameters['asof'];
if ( !$user->isRegistered() ) {
$result = 0;
} else {
// HACK: If there's no registration date, assume 2008-01-15, Wikipedia Day
// in the year before the new user log was created. See T243469.
$registration = $user->getRegistration() ?? "20080115000000";
$result = (int)wfTimestamp( TS_UNIX, $asOf ) - (int)wfTimestamp( TS_UNIX, $registration );
}
break;
case 'page-age':
/** @var Title $title */
$title = $parameters['title'];
$firstRev = $this->revisionLookup->getFirstRevision( $title );
$firstRevisionTime = $firstRev ? $firstRev->getTimestamp() : null;
if ( !$firstRevisionTime ) {
$result = 0;
break;
}
$asOf = $parameters['asof'];
$result = (int)wfTimestamp( TS_UNIX, $asOf ) - (int)wfTimestamp( TS_UNIX, $firstRevisionTime );
break;
case 'length':
$s = $getVarCB( $parameters['length-var'] )->toString();
$result = strlen( $s );
break;
case 'subtract-int':
$v1 = $getVarCB( $parameters['val1-var'] )->toInt();
$v2 = $getVarCB( $parameters['val2-var'] )->toInt();
$result = $v1 - $v2;
break;
case 'content-model-by-id':
$revRec = $this->revisionLookup->getRevisionById( $parameters['revid'] );
$result = $this->getContentModelFromRevision( $revRec );
break;
case 'revision-text-by-id':
$revRec = $this->revisionLookup->getRevisionById( $parameters['revid'] );
$result = $this->textExtractor->revisionToString( $revRec, $parameters['contextUser'] );
break;
case 'get-wiki-name':
$result = $this->wikiID;
break;
case 'get-wiki-language':
$result = $this->contentLanguage->getCode();
break;
default:
if ( $this->hookRunner->onAbuseFilter_computeVariable(
$varMethod,
$vars,
$parameters,
$result
) ) {
throw new UnexpectedValueException( 'Unknown variable compute type ' . $varMethod );
}
}
return $result instanceof AFPData ? $result : AFPData::newFromPHPVar( $result );
}
/**
* @param WikiPage $article
* @return array
*/
private function getLinksFromDB( WikiPage $article ) {
$id = $article->getId();
if ( !$id ) {
return [];
}
return ExternalLinksLookup::getExternalLinksForPage(
$id,
$this->lbFactory->getReplicaDatabase(),
__METHOD__
);
}
/**
* @todo Move to MW core (T272050)
* @param Title $title
* @return string[] Usernames of the last 10 (unique) authors from $title
*/
private function getLastPageAuthors( Title $title ) {
if ( !$title->exists() ) {
return [];
}
$fname = __METHOD__;
return $this->wanCache->getWithSetCallback(
$this->wanCache->makeKey( 'last-10-authors', 'revision', $title->getLatestRevID() ),
WANObjectCache::TTL_MINUTE,
function ( $oldValue, &$ttl, array &$setOpts ) use ( $title, $fname ) {
$dbr = $this->lbFactory->getReplicaDatabase();
$setOpts += Database::getCacheSetOptions( $dbr );
// Get the last 100 edit authors with a trivial query (avoid T116557)
$revQuery = $this->revisionStore->getQueryInfo();
$revAuthors = $dbr->selectFieldValues(
$revQuery['tables'],
$revQuery['fields']['rev_user_text'],
[
'rev_page' => $title->getArticleID(),
// TODO Should deleted names be counted in the 10 authors? If yes, this check should
// be moved inside the foreach
'rev_deleted' => 0
],
$fname,
// Some pages have < 10 authors but many revisions (e.g. bot pages)
[ 'ORDER BY' => 'rev_timestamp DESC, rev_id DESC',
'LIMIT' => 100,
// Force index per T116557
'USE INDEX' => [ 'revision' => 'rev_page_timestamp' ],
],
$revQuery['joins']
);
// Get the last 10 distinct authors within this set of edits
$users = [];
foreach ( $revAuthors as $author ) {
$users[$author] = 1;
if ( count( $users ) >= 10 ) {
break;
}
}
return array_keys( $users );
}
);
}
/**
* @param ?RevisionRecord $revision
* @return string
*/
private function getContentModelFromRevision( ?RevisionRecord $revision ): string {
// this is consistent with what is done on various places in RunVariableGenerator
// and RCVariableGenerator
if ( $revision !== null ) {
$content = $revision->getContent( SlotRecord::MAIN, RevisionRecord::RAW );
return $content->getModel();
}
return '';
}
/**
* It's like WikiPage::prepareContentForEdit, but not for editing (old wikitext usually)
*
* @param string $wikitext
* @param WikiPage $article
* @param UserIdentity $userIdentity Context user
*
* @return stdClass
*/
private function parseNonEditWikitext( $wikitext, WikiPage $article, UserIdentity $userIdentity ) {
static $cache = [];
$cacheKey = md5( $wikitext ) . ':' . $article->getTitle()->getPrefixedText();
if ( !isset( $cache[$cacheKey] ) ) {
$options = ParserOptions::newFromUser( $userIdentity );
$cache[$cacheKey] = (object)[
'output' => $this->parser->parse( $wikitext, $article->getTitle(), $options )
];
}
return $cache[$cacheKey];
}
}