wiki.techinc.nl/includes/Rest/Handler/PageHistoryCountHandler.php
daniel c4382301cc REST Handlers: use max-age not maxage for cache-control
Smally typo, big consequence.

Change-Id: I1d8f43dd3b11e4854b08d41fb5f0c7ede3dba90e
2020-03-25 22:38:03 +01:00

694 lines
19 KiB
PHP

<?php
namespace MediaWiki\Rest\Handler;
use MediaWiki\Permissions\PermissionManager;
use MediaWiki\Rest\LocalizedHttpException;
use MediaWiki\Rest\Response;
use MediaWiki\Rest\SimpleHandler;
use MediaWiki\Revision\RevisionRecord;
use MediaWiki\Revision\RevisionStore;
use MediaWiki\Storage\NameTableAccessException;
use MediaWiki\Storage\NameTableStore;
use MediaWiki\Storage\NameTableStoreFactory;
use RequestContext;
use Title;
use User;
use WANObjectCache;
use Wikimedia\Message\MessageValue;
use Wikimedia\Message\ParamType;
use Wikimedia\Message\ScalarParam;
use Wikimedia\ParamValidator\ParamValidator;
use Wikimedia\Rdbms\ILoadBalancer;
/**
* Handler class for Core REST API endpoints that perform operations on revisions
*/
class PageHistoryCountHandler extends SimpleHandler {
/** The maximum number of counts to return per type of revision */
private const COUNT_LIMITS = [
'anonymous' => 10000,
'bot' => 10000,
'editors' => 25000,
'edits' => 30000,
'minor' => 1000,
'reverted' => 30000
];
private const DEPRECATED_COUNT_TYPES = [
'anonedits' => 'anonymous',
'botedits' => 'bot',
'revertededits' => 'reverted'
];
private const MAX_AGE_200 = 60;
private const REVERTED_TAG_NAMES = [ 'mw-undo', 'mw-rollback' ];
/** @var RevisionStore */
private $revisionStore;
/** @var NameTableStore */
private $changeTagDefStore;
/** @var PermissionManager */
private $permissionManager;
/** @var ILoadBalancer */
private $loadBalancer;
/** @var WANObjectCache */
private $cache;
/** @var User */
private $user;
/** @var RevisionRecord|bool */
private $revision;
/** @var array */
private $lastModifiedTimes;
/** @var Title */
private $titleObject;
/**
* @param RevisionStore $revisionStore
* @param NameTableStoreFactory $nameTableStoreFactory
* @param PermissionManager $permissionManager
* @param ILoadBalancer $loadBalancer
* @param WANObjectCache $cache
*/
public function __construct(
RevisionStore $revisionStore,
NameTableStoreFactory $nameTableStoreFactory,
PermissionManager $permissionManager,
ILoadBalancer $loadBalancer,
WANObjectCache $cache
) {
$this->revisionStore = $revisionStore;
$this->changeTagDefStore = $nameTableStoreFactory->getChangeTagDef();
$this->permissionManager = $permissionManager;
$this->loadBalancer = $loadBalancer;
$this->cache = $cache;
// @todo Inject this, when there is a good way to do that
$this->user = RequestContext::getMain()->getUser();
}
private function normalizeType( $type ) {
return self::DEPRECATED_COUNT_TYPES[$type] ?? $type;
}
/**
* Validates that the provided parameter combination is supported.
*
* @param string $type
* @throws LocalizedHttpException
*/
private function validateParameterCombination( $type ) {
$params = $this->getValidatedParams();
if ( !$params ) {
return;
}
if ( $params['from'] || $params['to'] ) {
if ( $type === 'edits' || $type === 'editors' ) {
if ( !$params['from'] || !$params['to'] ) {
throw new LocalizedHttpException(
new MessageValue( 'rest-pagehistorycount-parameters-invalid' ),
400
);
}
} else {
throw new LocalizedHttpException(
new MessageValue( 'rest-pagehistorycount-parameters-invalid' ),
400
);
}
}
}
/**
* @param Title $title the title of the page to load history for
* @param string $type the validated count type
* @return Response
* @throws LocalizedHttpException
*/
public function run( $title, $type ) {
$normalizedType = $this->normalizeType( $type );
$this->validateParameterCombination( $normalizedType );
$titleObj = $this->getTitle();
if ( !$titleObj || !$titleObj->getArticleID() ) {
throw new LocalizedHttpException(
new MessageValue( 'rest-nonexistent-title',
[ new ScalarParam( ParamType::PLAINTEXT, $title ) ]
),
404
);
}
if ( !$this->permissionManager->userCan( 'read', $this->user, $titleObj ) ) {
throw new LocalizedHttpException(
new MessageValue( 'rest-permission-denied-title',
[ new ScalarParam( ParamType::PLAINTEXT, $title ) ]
),
403
);
}
$count = $this->getCount( $normalizedType );
$countLimit = self::COUNT_LIMITS[$normalizedType];
$response = $this->getResponseFactory()->createJson( [
'count' => $count > $countLimit ? $countLimit : $count,
'limit' => $count > $countLimit
] );
$response->setHeader( 'Cache-Control', 'max-age=' . self::MAX_AGE_200 );
// Inform clients who use a deprecated "type" value, so they can adjust
if ( isset( self::DEPRECATED_COUNT_TYPES[$type] ) ) {
$docs = '<https://www.mediawiki.org/wiki/API:REST/History_API' .
'#Get_page_history_counts>; rel="deprecation"';
$response->setHeader( 'Deprecation', 'version="v1"' );
$response->setHeader( 'Link', $docs );
}
return $response;
}
/**
* @param string $type the validated count type
* @return int the article count
* @throws LocalizedHttpException
*/
private function getCount( $type ) {
$pageId = $this->getTitle()->getArticleID();
switch ( $type ) {
case 'anonymous':
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getAnonCount( $pageId, $fromRev );
}
);
case 'bot':
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getBotCount( $pageId, $fromRev );
}
);
case 'editors':
$from = $this->getValidatedParams()['from'] ?? null;
$to = $this->getValidatedParams()['to'] ?? null;
if ( $from || $to ) {
return $this->getEditorsCount(
$pageId,
$from ? $this->getRevisionOrThrow( $from ) : null,
$to ? $this->getRevisionOrThrow( $to ) : null
);
} else {
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getEditorsCount( $pageId, $fromRev );
} );
}
case 'edits':
$from = $this->getValidatedParams()['from'] ?? null;
$to = $this->getValidatedParams()['to'] ?? null;
if ( $from || $to ) {
return $this->getEditsCount(
$pageId,
$from ? $this->getRevisionOrThrow( $from ) : null,
$to ? $this->getRevisionOrThrow( $to ) : null
);
} else {
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getEditsCount( $pageId, $fromRev );
}
);
}
case 'reverted':
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getRevertedCount( $pageId, $fromRev );
}
);
case 'minor':
// The query for minor counts is inefficient for the database for pages with many revisions.
// If the specified title contains more revisions than allowed, we will return an error.
$editsCount = $this->getCachedCount( 'edits',
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getEditsCount( $pageId, $fromRev );
}
);
if ( $editsCount > self::COUNT_LIMITS[$type] * 2 ) {
throw new LocalizedHttpException(
new MessageValue( 'rest-pagehistorycount-too-many-revisions' ),
500
);
}
return $this->getCachedCount( $type,
function ( RevisionRecord $fromRev = null ) use ( $pageId ) {
return $this->getMinorCount( $pageId, $fromRev );
}
);
// Sanity check
default:
throw new LocalizedHttpException(
new MessageValue( 'rest-pagehistorycount-type-unrecognized',
[ new ScalarParam( ParamType::PLAINTEXT, $type ) ]
),
500
);
}
}
/**
* @return RevisionRecord|bool current revision or false if unable to retrieve revision
*/
private function getCurrentRevision() {
if ( $this->revision === null ) {
$title = $this->getTitle();
if ( $title && $title->getArticleID() ) {
$this->revision = $this->revisionStore->getKnownCurrentRevision( $title );
} else {
$this->revision = false;
}
}
return $this->revision;
}
/**
* @return Title|bool Title or false if unable to retrieve title
*/
private function getTitle() {
if ( $this->titleObject === null ) {
$this->titleObject = Title::newFromText( $this->getValidatedParams()['title'] );
}
return $this->titleObject;
}
/**
* Returns latest of 2 timestamps:
* 1. Current revision
* 2. OR entry from the DB logging table for the given page
* @return int|null
*/
protected function getLastModified() {
$lastModifiedTimes = $this->getLastModifiedTimes();
if ( $lastModifiedTimes ) {
return max( array_values( $lastModifiedTimes ) );
}
}
/**
* Returns array with 2 timestamps:
* 1. Current revision
* 2. OR entry from the DB logging table for the given page
* @return array
*/
protected function getLastModifiedTimes() {
$currentRev = $this->getCurrentRevision();
if ( !$currentRev ) {
return null;
}
if ( $this->lastModifiedTimes === null ) {
$currentRevTime = (int)wfTimestampOrNull( TS_UNIX, $currentRev->getTimestamp() );
$loggingTableTime = $this->loggingTableTime( $currentRev->getPageId() );
$this->lastModifiedTimes = [
'currentRevTS' => $currentRevTime,
'dependencyModTS' => $loggingTableTime
];
}
return $this->lastModifiedTimes;
}
/**
* Return timestamp of latest entry in logging table for given page id
* @param int $pageId
* @return int|null
*/
private function loggingTableTime( $pageId ) {
$res = $this->loadBalancer->getConnectionRef( DB_REPLICA )->selectField(
'logging',
'MAX(log_timestamp)',
[ 'log_page' => $pageId ],
__METHOD__
);
return $res ? (int)wfTimestamp( TS_UNIX, $res ) : null;
}
/**
* Choosing to not implement etags in this handler.
* Generating an etag when getting revision counts must account for things like visibility settings
* (e.g. rev_deleted bit) which requires hitting the database anyway. The response for these
* requests are so small that we wouldn't be gaining much efficiency.
* Etags are strong validators and if provided would take precendence over
* last modified time, a weak validator. We want to ensure only last modified time is used
* since it is more efficient than using etags for this particular case.
* @return null
*/
protected function getEtag() {
return null;
}
/**
* @param string $type
* @param callable $fetchCount
* @return int
*/
private function getCachedCount( $type,
callable $fetchCount
) {
$titleObj = $this->getTitle();
$pageId = $titleObj->getArticleID();
return $this->cache->getWithSetCallback(
$this->cache->makeKey( 'rest', 'pagehistorycount', $pageId, $type ),
WANObjectCache::TTL_WEEK,
function ( $oldValue ) use ( $fetchCount ) {
$currentRev = $this->getCurrentRevision();
if ( $oldValue ) {
// Last modified timestamp was NOT a dependency change (e.g. revdel)
$doIncrementalUpdate = (
$this->getLastModified() != $this->getLastModifiedTimes()['dependencyModTS']
);
if ( $doIncrementalUpdate ) {
$rev = $this->revisionStore->getRevisionById( $oldValue['revision'] );
if ( $rev ) {
$additionalCount = $fetchCount( $rev );
return [
'revision' => $currentRev->getId(),
'count' => $oldValue['count'] + $additionalCount,
'dependencyModTS' => $this->getLastModifiedTimes()['dependencyModTS']
];
}
}
}
// Nothing was previously stored, or incremental update was done for too long,
// recalculate from scratch.
return [
'revision' => $currentRev->getId(),
'count' => $fetchCount(),
'dependencyModTS' => $this->getLastModifiedTimes()['dependencyModTS']
];
},
[
'touchedCallback' => function (){
return $this->getLastModified();
},
'version' => 2,
'lockTSE' => WANObjectCache::TTL_MINUTE * 5
]
)['count'];
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @return int the count
*/
protected function getAnonCount( $pageId, RevisionRecord $fromRev = null ) {
$dbr = $this->loadBalancer->getConnectionRef( DB_REPLICA );
$cond = [
'rev_page' => $pageId,
'actor_user IS NULL',
$dbr->bitAnd( 'rev_deleted',
RevisionRecord::DELETED_TEXT | RevisionRecord::DELETED_USER ) . " = 0"
];
if ( $fromRev ) {
$oldTs = $dbr->addQuotes( $dbr->timestamp( $fromRev->getTimestamp() ) );
$cond[] = "(rev_timestamp = {$oldTs} AND rev_id > {$fromRev->getId()}) " .
"OR rev_timestamp > {$oldTs}";
}
$edits = $dbr->selectRowCount(
[
'revision_actor_temp',
'revision',
'actor'
],
'1',
$cond,
__METHOD__,
[ 'LIMIT' => self::COUNT_LIMITS['anonymous'] + 1 ], // extra to detect truncation
[
'revision' => [
'JOIN',
'revactor_rev = rev_id AND revactor_page = rev_page'
],
'actor' => [
'JOIN',
'revactor_actor = actor_id'
]
]
);
return $edits;
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @return int the count
*/
protected function getBotCount( $pageId, RevisionRecord $fromRev = null ) {
$dbr = $this->loadBalancer->getConnectionRef( DB_REPLICA );
$cond = [
'rev_page=' . intval( $pageId ),
$dbr->bitAnd( 'rev_deleted',
RevisionRecord::DELETED_TEXT | RevisionRecord::DELETED_USER ) . " = 0",
'EXISTS(' .
$dbr->selectSQLText(
'user_groups',
'1',
[
'actor.actor_user = ug_user',
'ug_group' => $this->permissionManager->getGroupsWithPermission( 'bot' ),
'ug_expiry IS NULL OR ug_expiry >= ' . $dbr->addQuotes( $dbr->timestamp() )
],
__METHOD__
) .
')'
];
if ( $fromRev ) {
$oldTs = $dbr->addQuotes( $dbr->timestamp( $fromRev->getTimestamp() ) );
$cond[] = "(rev_timestamp = {$oldTs} AND rev_id > {$fromRev->getId()}) " .
"OR rev_timestamp > {$oldTs}";
}
$edits = $dbr->selectRowCount(
[
'revision_actor_temp',
'revision',
'actor',
],
'1',
$cond,
__METHOD__,
[ 'LIMIT' => self::COUNT_LIMITS['bot'] + 1 ], // extra to detect truncation
[
'revision' => [
'JOIN',
'revactor_rev = rev_id AND revactor_page = rev_page'
],
'actor' => [
'JOIN',
'revactor_actor = actor_id'
],
]
);
return $edits;
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @param RevisionRecord|null $toRev
* @return int the count
*/
protected function getEditorsCount( $pageId,
RevisionRecord $fromRev = null,
RevisionRecord $toRev = null
) {
list( $fromRev, $toRev ) = $this->orderRevisions( $fromRev, $toRev );
return $this->revisionStore->countAuthorsBetween( $pageId, $fromRev,
$toRev, $this->user, self::COUNT_LIMITS['editors'] );
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @return int the count
*/
protected function getRevertedCount( $pageId, RevisionRecord $fromRev = null ) {
$tagIds = [];
foreach ( self::REVERTED_TAG_NAMES as $tagName ) {
try {
$tagIds[] = $this->changeTagDefStore->getId( $tagName );
} catch ( NameTableAccessException $e ) {
// If no revisions are tagged with a name, no tag id will be present
}
}
if ( !$tagIds ) {
return 0;
}
$dbr = $this->loadBalancer->getConnectionRef( DB_REPLICA );
$cond = [
'rev_page' => $pageId,
$dbr->bitAnd( 'rev_deleted', RevisionRecord::DELETED_TEXT ) . " = 0"
];
if ( $fromRev ) {
$oldTs = $dbr->addQuotes( $dbr->timestamp( $fromRev->getTimestamp() ) );
$cond[] = "(rev_timestamp = {$oldTs} AND rev_id > {$fromRev->getId()}) " .
"OR rev_timestamp > {$oldTs}";
}
$edits = $dbr->selectRowCount(
[
'revision',
'change_tag'
],
'1',
[ 'rev_page' => $pageId ],
__METHOD__,
[
'LIMIT' => self::COUNT_LIMITS['reverted'] + 1, // extra to detect truncation
'GROUP BY' => 'rev_id'
],
[
'change_tag' => [
'JOIN',
[
'ct_rev_id = rev_id',
'ct_tag_id' => $tagIds,
]
],
]
);
return $edits;
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @return int the count
*/
protected function getMinorCount( $pageId, RevisionRecord $fromRev = null ) {
$dbr = $this->loadBalancer->getConnectionRef( DB_REPLICA );
$cond = [
'rev_page' => $pageId,
'rev_minor_edit != 0',
$dbr->bitAnd( 'rev_deleted', RevisionRecord::DELETED_TEXT ) . " = 0"
];
if ( $fromRev ) {
$oldTs = $dbr->addQuotes( $dbr->timestamp( $fromRev->getTimestamp() ) );
$cond[] = "(rev_timestamp = {$oldTs} AND rev_id > {$fromRev->getId()}) " .
"OR rev_timestamp > {$oldTs}";
}
$edits = $dbr->selectRowCount( 'revision', '1',
$cond,
__METHOD__,
[ 'LIMIT' => self::COUNT_LIMITS['minor'] + 1 ] // extra to detect truncation
);
return $edits;
}
/**
* @param int $pageId the id of the page to load history for
* @param RevisionRecord|null $fromRev
* @param RevisionRecord|null $toRev
* @return int the count
*/
protected function getEditsCount(
$pageId,
RevisionRecord $fromRev = null,
RevisionRecord $toRev = null
) {
list( $fromRev, $toRev ) = $this->orderRevisions( $fromRev, $toRev );
return $this->revisionStore->countRevisionsBetween(
$pageId,
$fromRev,
$toRev,
self::COUNT_LIMITS['edits'] // Will be increased by 1 to detect truncation
);
}
/**
* @param int $revId
* @return RevisionRecord
* @throws LocalizedHttpException
*/
private function getRevisionOrThrow( $revId ) {
$rev = $this->revisionStore->getRevisionById( $revId );
if ( !$rev ) {
throw new LocalizedHttpException(
new MessageValue( 'rest-nonexistent-revision', [ $revId ] ),
404
);
}
return $rev;
}
/**
* Reorders revisions if they are present
* @param RevisionRecord|null $fromRev
* @param RevisionRecord|null $toRev
* @return array
* @phan-return array{0:RevisionRecord|null,1:RevisionRecord|null}
*/
private function orderRevisions(
RevisionRecord $fromRev = null,
RevisionRecord $toRev = null
) {
if ( $fromRev && $toRev && ( $fromRev->getTimestamp() > $toRev->getTimestamp() ||
( $fromRev->getTimestamp() === $toRev->getTimestamp()
&& $fromRev->getId() > $toRev->getId() ) )
) {
return [ $toRev, $fromRev ];
}
return [ $fromRev, $toRev ];
}
public function needsWriteAccess() {
return false;
}
public function getParamSettings() {
return [
'title' => [
self::PARAM_SOURCE => 'path',
ParamValidator::PARAM_TYPE => 'string',
ParamValidator::PARAM_REQUIRED => true,
],
'type' => [
self::PARAM_SOURCE => 'path',
ParamValidator::PARAM_TYPE => array_merge(
array_keys( self::COUNT_LIMITS ),
array_keys( self::DEPRECATED_COUNT_TYPES )
),
ParamValidator::PARAM_REQUIRED => true,
],
'from' => [
self::PARAM_SOURCE => 'query',
ParamValidator::PARAM_TYPE => 'integer',
ParamValidator::PARAM_REQUIRED => false
],
'to' => [
self::PARAM_SOURCE => 'query',
ParamValidator::PARAM_TYPE => 'integer',
ParamValidator::PARAM_REQUIRED => false
]
];
}
}