ApiQueryAllDeletedRevisions.php

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<?php
class ApiQueryAllDeletedRevisions extends ApiQueryRevisionsBase {

    public function __construct( ApiQuery $query, $moduleName ) {
        parent::__construct( $query, $moduleName, 'adr' );
    }

    protected function run( ApiPageSet $resultPageSet = null ) {
        $user = $this->getUser();
        // Before doing anything at all, let's check permissions
        if ( !$user->isAllowed( 'deletedhistory' ) ) {
            $this->dieUsage(
                'You don\'t have permission to view deleted revision information',
                'permissiondenied'
            );
        }

        $db = $this->getDB();
        $params = $this->extractRequestParams( false );

        $result = $this->getResult();

        // If the user wants no namespaces, they get no pages.
        if ( $params['namespace'] === [] ) {
            if ( $resultPageSet === null ) {
                $result->addValue( 'query', $this->getModuleName(), [] );
            }
            return;
        }

        // This module operates in two modes:
        // 'user': List deleted revs by a certain user
        // 'all': List all deleted revs in NS
        $mode = 'all';
        if ( !is_null( $params['user'] ) ) {
            $mode = 'user';
        }

        if ( $mode == 'user' ) {
            foreach ( [ 'from', 'to', 'prefix', 'excludeuser' ] as $param ) {
                if ( !is_null( $params[$param] ) ) {
                    $p = $this->getModulePrefix();
                    $this->dieUsage( "The '{$p}{$param}' parameter cannot be used with '{$p}user'",
                        'badparams' );
                }
            }
        } else {
            foreach ( [ 'start', 'end' ] as $param ) {
                if ( !is_null( $params[$param] ) ) {
                    $p = $this->getModulePrefix();
                    $this->dieUsage( "The '{$p}{$param}' parameter may only be used with '{$p}user'",
                        'badparams' );
                }
            }
        }

        // If we're generating titles only, we can use DISTINCT for a better
        // query. But we can't do that in 'user' mode (wrong index), and we can
        // only do it when sorting ASC (because MySQL apparently can't use an
        // index backwards for grouping even though it can for ORDER BY, WTF?)
        $dir = $params['dir'];
        $optimizeGenerateTitles = false;
        if ( $mode === 'all' && $params['generatetitles'] && $resultPageSet !== null ) {
            if ( $dir === 'newer' ) {
                $optimizeGenerateTitles = true;
            } else {
                $p = $this->getModulePrefix();
                $this->setWarning( "For better performance when generating titles, set {$p}dir=newer" );
            }
        }

        $this->addTables( 'archive' );
        if ( $resultPageSet === null ) {
            $this->parseParameters( $params );
            $this->addFields( Revision::selectArchiveFields() );
            $this->addFields( [ 'ar_title', 'ar_namespace' ] );
        } else {
            $this->limit = $this->getParameter( 'limit' ) ?: 10;
            $this->addFields( [ 'ar_title', 'ar_namespace' ] );
            if ( $optimizeGenerateTitles ) {
                $this->addOption( 'DISTINCT' );
            } else {
                $this->addFields( [ 'ar_timestamp', 'ar_rev_id', 'ar_id' ] );
            }
        }

        if ( $this->fld_tags ) {
            $this->addTables( 'tag_summary' );
            $this->addJoinConds(
                [ 'tag_summary' => [ 'LEFT JOIN', [ 'ar_rev_id=ts_rev_id' ] ] ]
            );
            $this->addFields( 'ts_tags' );
        }

        if ( !is_null( $params['tag'] ) ) {
            $this->addTables( 'change_tag' );
            $this->addJoinConds(
                [ 'change_tag' => [ 'INNER JOIN', [ 'ar_rev_id=ct_rev_id' ] ] ]
            );
            $this->addWhereFld( 'ct_tag', $params['tag'] );
        }

        if ( $this->fetchContent ) {
            // Modern MediaWiki has the content for deleted revs in the 'text'
            // table using fields old_text and old_flags. But revisions deleted
            // pre-1.5 store the content in the 'archive' table directly using
            // fields ar_text and ar_flags, and no corresponding 'text' row. So
            // we have to LEFT JOIN and fetch all four fields.
            $this->addTables( 'text' );
            $this->addJoinConds(
                [ 'text' => [ 'LEFT JOIN', [ 'ar_text_id=old_id' ] ] ]
            );
            $this->addFields( [ 'ar_text', 'ar_flags', 'old_text', 'old_flags' ] );

            // This also means stricter restrictions
            if ( !$user->isAllowedAny( 'undelete', 'deletedtext' ) ) {
                $this->dieUsage(
                    'You don\'t have permission to view deleted revision content',
                    'permissiondenied'
                );
            }
        }

        $miser_ns = null;

        if ( $mode == 'all' ) {
            if ( $params['namespace'] !== null ) {
                $namespaces = $params['namespace'];
            } else {
                $namespaces = MWNamespace::getValidNamespaces();
            }
            $this->addWhereFld( 'ar_namespace', $namespaces );

            // For from/to/prefix, we have to consider the potential
            // transformations of the title in all specified namespaces.
            // Generally there will be only one transformation, but wikis with
            // some namespaces case-sensitive could have two.
            if ( $params['from'] !== null || $params['to'] !== null ) {
                $isDirNewer = ( $dir === 'newer' );
                $after = ( $isDirNewer ? '>=' : '<=' );
                $before = ( $isDirNewer ? '<=' : '>=' );
                $where = [];
                foreach ( $namespaces as $ns ) {
                    $w = [];
                    if ( $params['from'] !== null ) {
                        $w[] = 'ar_title' . $after .
                            $db->addQuotes( $this->titlePartToKey( $params['from'], $ns ) );
                    }
                    if ( $params['to'] !== null ) {
                        $w[] = 'ar_title' . $before .
                            $db->addQuotes( $this->titlePartToKey( $params['to'], $ns ) );
                    }
                    $w = $db->makeList( $w, LIST_AND );
                    $where[$w][] = $ns;
                }
                if ( count( $where ) == 1 ) {
                    $where = key( $where );
                    $this->addWhere( $where );
                } else {
                    $where2 = [];
                    foreach ( $where as $w => $ns ) {
                        $where2[] = $db->makeList( [ $w, 'ar_namespace' => $ns ], LIST_AND );
                    }
                    $this->addWhere( $db->makeList( $where2, LIST_OR ) );
                }
            }

            if ( isset( $params['prefix'] ) ) {
                $where = [];
                foreach ( $namespaces as $ns ) {
                    $w = 'ar_title' . $db->buildLike(
                        $this->titlePartToKey( $params['prefix'], $ns ),
                        $db->anyString() );
                    $where[$w][] = $ns;
                }
                if ( count( $where ) == 1 ) {
                    $where = key( $where );
                    $this->addWhere( $where );
                } else {
                    $where2 = [];
                    foreach ( $where as $w => $ns ) {
                        $where2[] = $db->makeList( [ $w, 'ar_namespace' => $ns ], LIST_AND );
                    }
                    $this->addWhere( $db->makeList( $where2, LIST_OR ) );
                }
            }
        } else {
            if ( $this->getConfig()->get( 'MiserMode' ) ) {
                $miser_ns = $params['namespace'];
            } else {
                $this->addWhereFld( 'ar_namespace', $params['namespace'] );
            }
            $this->addTimestampWhereRange( 'ar_timestamp', $dir, $params['start'], $params['end'] );
        }

        if ( !is_null( $params['user'] ) ) {
            $this->addWhereFld( 'ar_user_text', $params['user'] );
        } elseif ( !is_null( $params['excludeuser'] ) ) {
            $this->addWhere( 'ar_user_text != ' .
                $db->addQuotes( $params['excludeuser'] ) );
        }

        if ( !is_null( $params['user'] ) || !is_null( $params['excludeuser'] ) ) {
            // Paranoia: avoid brute force searches (bug 17342)
            // (shouldn't be able to get here without 'deletedhistory', but
            // check it again just in case)
            if ( !$user->isAllowed( 'deletedhistory' ) ) {
                $bitmask = Revision::DELETED_USER;
            } elseif ( !$user->isAllowedAny( 'suppressrevision', 'viewsuppressed' ) ) {
                $bitmask = Revision::DELETED_USER | Revision::DELETED_RESTRICTED;
            } else {
                $bitmask = 0;
            }
            if ( $bitmask ) {
                $this->addWhere( $db->bitAnd( 'ar_deleted', $bitmask ) . " != $bitmask" );
            }
        }

        if ( !is_null( $params['continue'] ) ) {
            $cont = explode( '|', $params['continue'] );
            $op = ( $dir == 'newer' ? '>' : '<' );
            if ( $optimizeGenerateTitles ) {
                $this->dieContinueUsageIf( count( $cont ) != 2 );
                $ns = intval( $cont[0] );
                $this->dieContinueUsageIf( strval( $ns ) !== $cont[0] );
                $title = $db->addQuotes( $cont[1] );
                $this->addWhere( "ar_namespace $op $ns OR " .
                    "(ar_namespace = $ns AND ar_title $op= $title)" );
            } elseif ( $mode == 'all' ) {
                $this->dieContinueUsageIf( count( $cont ) != 4 );
                $ns = intval( $cont[0] );
                $this->dieContinueUsageIf( strval( $ns ) !== $cont[0] );
                $title = $db->addQuotes( $cont[1] );
                $ts = $db->addQuotes( $db->timestamp( $cont[2] ) );
                $ar_id = (int)$cont[3];
                $this->dieContinueUsageIf( strval( $ar_id ) !== $cont[3] );
                $this->addWhere( "ar_namespace $op $ns OR " .
                    "(ar_namespace = $ns AND " .
                    "(ar_title $op $title OR " .
                    "(ar_title = $title AND " .
                    "(ar_timestamp $op $ts OR " .
                    "(ar_timestamp = $ts AND " .
                    "ar_id $op= $ar_id)))))" );
            } else {
                $this->dieContinueUsageIf( count( $cont ) != 2 );
                $ts = $db->addQuotes( $db->timestamp( $cont[0] ) );
                $ar_id = (int)$cont[1];
                $this->dieContinueUsageIf( strval( $ar_id ) !== $cont[1] );
                $this->addWhere( "ar_timestamp $op $ts OR " .
                    "(ar_timestamp = $ts AND " .
                    "ar_id $op= $ar_id)" );
            }
        }

        $this->addOption( 'LIMIT', $this->limit + 1 );

        $sort = ( $dir == 'newer' ? '' : ' DESC' );
        $orderby = [];
        if ( $optimizeGenerateTitles ) {
            // Targeting index name_title_timestamp
            if ( $params['namespace'] === null || count( array_unique( $params['namespace'] ) ) > 1 ) {
                $orderby[] = "ar_namespace $sort";
            }
            $orderby[] = "ar_title $sort";
        } elseif ( $mode == 'all' ) {
            // Targeting index name_title_timestamp
            if ( $params['namespace'] === null || count( array_unique( $params['namespace'] ) ) > 1 ) {
                $orderby[] = "ar_namespace $sort";
            }
            $orderby[] = "ar_title $sort";
            $orderby[] = "ar_timestamp $sort";
            $orderby[] = "ar_id $sort";
        } else {
            // Targeting index usertext_timestamp
            // 'user' is always constant.
            $orderby[] = "ar_timestamp $sort";
            $orderby[] = "ar_id $sort";
        }
        $this->addOption( 'ORDER BY', $orderby );

        $res = $this->select( __METHOD__ );
        $pageMap = []; // Maps ns&title to array index
        $count = 0;
        $nextIndex = 0;
        $generated = [];
        foreach ( $res as $row ) {
            if ( ++$count > $this->limit ) {
                // We've had enough
                if ( $optimizeGenerateTitles ) {
                    $this->setContinueEnumParameter( 'continue', "$row->ar_namespace|$row->ar_title" );
                } elseif ( $mode == 'all' ) {
                    $this->setContinueEnumParameter( 'continue',
                        "$row->ar_namespace|$row->ar_title|$row->ar_timestamp|$row->ar_id"
                    );
                } else {
                    $this->setContinueEnumParameter( 'continue', "$row->ar_timestamp|$row->ar_id" );
                }
                break;
            }

            // Miser mode namespace check
            if ( $miser_ns !== null && !in_array( $row->ar_namespace, $miser_ns ) ) {
                continue;
            }

            if ( $resultPageSet !== null ) {
                if ( $params['generatetitles'] ) {
                    $key = "{$row->ar_namespace}:{$row->ar_title}";
                    if ( !isset( $generated[$key] ) ) {
                        $generated[$key] = Title::makeTitle( $row->ar_namespace, $row->ar_title );
                    }
                } else {
                    $generated[] = $row->ar_rev_id;
                }
            } else {
                $revision = Revision::newFromArchiveRow( $row );
                $rev = $this->extractRevisionInfo( $revision, $row );

                if ( !isset( $pageMap[$row->ar_namespace][$row->ar_title] ) ) {
                    $index = $nextIndex++;
                    $pageMap[$row->ar_namespace][$row->ar_title] = $index;
                    $title = $revision->getTitle();
                    $a = [
                        'pageid' => $title->getArticleID(),
                        'revisions' => [ $rev ],
                    ];
                    ApiResult::setIndexedTagName( $a['revisions'], 'rev' );
                    ApiQueryBase::addTitleInfo( $a, $title );
                    $fit = $result->addValue( [ 'query', $this->getModuleName() ], $index, $a );
                } else {
                    $index = $pageMap[$row->ar_namespace][$row->ar_title];
                    $fit = $result->addValue(
                        [ 'query', $this->getModuleName(), $index, 'revisions' ],
                        null, $rev );
                }
                if ( !$fit ) {
                    if ( $mode == 'all' ) {
                        $this->setContinueEnumParameter( 'continue',
                            "$row->ar_namespace|$row->ar_title|$row->ar_timestamp|$row->ar_id"
                        );
                    } else {
                        $this->setContinueEnumParameter( 'continue', "$row->ar_timestamp|$row->ar_id" );
                    }
                    break;
                }
            }
        }

        if ( $resultPageSet !== null ) {
            if ( $params['generatetitles'] ) {
                $resultPageSet->populateFromTitles( $generated );
            } else {
                $resultPageSet->populateFromRevisionIDs( $generated );
            }
        } else {
            $result->addIndexedTagName( [ 'query', $this->getModuleName() ], 'page' );
        }
    }

    public function getAllowedParams() {
        $ret = parent::getAllowedParams() + [
            'user' => [
                ApiBase::PARAM_TYPE => 'user'
            ],
            'namespace' => [
                ApiBase::PARAM_ISMULTI => true,
                ApiBase::PARAM_TYPE => 'namespace',
            ],
            'start' => [
                ApiBase::PARAM_TYPE => 'timestamp',
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'useronly' ] ],
            ],
            'end' => [
                ApiBase::PARAM_TYPE => 'timestamp',
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'useronly' ] ],
            ],
            'dir' => [
                ApiBase::PARAM_TYPE => [
                    'newer',
                    'older'
                ],
                ApiBase::PARAM_DFLT => 'older',
                ApiBase::PARAM_HELP_MSG => 'api-help-param-direction',
            ],
            'from' => [
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'nonuseronly' ] ],
            ],
            'to' => [
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'nonuseronly' ] ],
            ],
            'prefix' => [
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'nonuseronly' ] ],
            ],
            'excludeuser' => [
                ApiBase::PARAM_TYPE => 'user',
                ApiBase::PARAM_HELP_MSG_INFO => [ [ 'nonuseronly' ] ],
            ],
            'tag' => null,
            'continue' => [
                ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
            ],
            'generatetitles' => [
                ApiBase::PARAM_DFLT => false
            ],
        ];

        if ( $this->getConfig()->get( 'MiserMode' ) ) {
            $ret['user'][ApiBase::PARAM_HELP_MSG_APPEND] = [
                'apihelp-query+alldeletedrevisions-param-miser-user-namespace',
            ];
            $ret['namespace'][ApiBase::PARAM_HELP_MSG_APPEND] = [
                'apihelp-query+alldeletedrevisions-param-miser-user-namespace',
            ];
        }

        return $ret;
    }

    protected function getExamplesMessages() {
        return [
            'action=query&list=alldeletedrevisions&adruser=Example&adrlimit=50'
                => 'apihelp-query+alldeletedrevisions-example-user',
            'action=query&list=alldeletedrevisions&adrdir=newer&adrnamespace=0&adrlimit=50'
                => 'apihelp-query+alldeletedrevisions-example-ns-main',
        ];
    }

    public function getHelpUrls() {
        return 'https://www.mediawiki.org/wiki/API:Alldeletedrevisions';
    }
}