Move remaining LoadBalancer classes to Rdbms

[mediawiki.git] / includes / revisiondelete / RevDelList.php

<?php
/**
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup RevisionDelete
 */

use MediaWiki\MediaWikiServices;

/**
 * Abstract base class for a list of deletable items. The list class
 * needs to be able to make a query from a set of identifiers to pull
 * relevant rows, to return RevDelItem subclasses wrapping them, and
 * to wrap bulk update operations.
 */
abstract class RevDelList extends RevisionListBase {
        function __construct( IContextSource $context, Title $title, array $ids ) {
                parent::__construct( $context, $title );
                $this->ids = $ids;
        }

        /**
         * Get the DB field name associated with the ID list.
         * This used to populate the log_search table for finding log entries.
         * Override this function.
         * @return string|null
         */
        public static function getRelationType() {
                return null;
        }

        /**
         * Get the user right required for this list type
         * Override this function.
         * @since 1.22
         * @return string|null
         */
        public static function getRestriction() {
                return null;
        }

        /**
         * Get the revision deletion constant for this list type
         * Override this function.
         * @since 1.22
         * @return int|null
         */
        public static function getRevdelConstant() {
                return null;
        }

        /**
         * Suggest a target for the revision deletion
         * Optionally override this function.
         * @since 1.22
         * @param Title|null $target User-supplied target
         * @param array $ids
         * @return Title|null
         */
        public static function suggestTarget( $target, array $ids ) {
                return $target;
        }

        /**
         * Indicate whether any item in this list is suppressed
         * @since 1.25
         * @return bool
         */
        public function areAnySuppressed() {
                $bit = $this->getSuppressBit();

                /** @var $item RevDelItem */
                foreach ( $this as $item ) {
                        if ( $item->getBits() & $bit ) {
                                return true;
                        }
                }

                return false;
        }

        /**
         * Set the visibility for the revisions in this list. Logging and
         * transactions are done here.
         *
         * @param array $params Associative array of parameters. Members are:
         *     value:         ExtractBitParams() bitfield array
         *     comment:       The log comment
         *     perItemStatus: Set if you want per-item status reports
         *     tags:          The array of change tags to apply to the log entry
         * @return Status
         * @since 1.23 Added 'perItemStatus' param
         */
        public function setVisibility( array $params ) {
                $status = Status::newGood();

                $bitPars = $params['value'];
                $comment = $params['comment'];
                $perItemStatus = isset( $params['perItemStatus'] ) ? $params['perItemStatus'] : false;

                // CAS-style checks are done on the _deleted fields so the select
                // does not need to use FOR UPDATE nor be in the atomic section
                $dbw = wfGetDB( DB_MASTER );
                $this->res = $this->doQuery( $dbw );

                $status->merge( $this->acquireItemLocks() );
                if ( !$status->isGood() ) {
                        return $status;
                }

                $dbw->startAtomic( __METHOD__ );
                $dbw->onTransactionResolution(
                        function () {
                                // Release locks on commit or error
                                $this->releaseItemLocks();
                        },
                        __METHOD__
                );

                $missing = array_flip( $this->ids );
                $this->clearFileOps();
                $idsForLog = [];
                $authorIds = $authorIPs = [];

                if ( $perItemStatus ) {
                        $status->itemStatuses = [];
                }

                // For multi-item deletions, set the old/new bitfields in log_params such that "hid X"
                // shows in logs if field X was hidden from ANY item and likewise for "unhid Y". Note the
                // form does not let the same field get hidden and unhidden in different items at once.
                $virtualOldBits = 0;
                $virtualNewBits = 0;
                $logType = 'delete';

                // Will be filled with id => [old, new bits] information and
                // passed to doPostCommitUpdates().
                $visibilityChangeMap = [];

                /** @var $item RevDelItem */
                foreach ( $this as $item ) {
                        unset( $missing[$item->getId()] );

                        if ( $perItemStatus ) {
                                $itemStatus = Status::newGood();
                                $status->itemStatuses[$item->getId()] = $itemStatus;
                        } else {
                                $itemStatus = $status;
                        }

                        $oldBits = $item->getBits();
                        // Build the actual new rev_deleted bitfield
                        $newBits = RevisionDeleter::extractBitfield( $bitPars, $oldBits );

                        if ( $oldBits == $newBits ) {
                                $itemStatus->warning(
                                        'revdelete-no-change', $item->formatDate(), $item->formatTime() );
                                $status->failCount++;
                                continue;
                        } elseif ( $oldBits == 0 && $newBits != 0 ) {
                                $opType = 'hide';
                        } elseif ( $oldBits != 0 && $newBits == 0 ) {
                                $opType = 'show';
                        } else {
                                $opType = 'modify';
                        }

                        if ( $item->isHideCurrentOp( $newBits ) ) {
                                // Cannot hide current version text
                                $itemStatus->error(
                                        'revdelete-hide-current', $item->formatDate(), $item->formatTime() );
                                $status->failCount++;
                                continue;
                        } elseif ( !$item->canView() ) {
                                // Cannot access this revision
                                $msg = ( $opType == 'show' ) ?
                                        'revdelete-show-no-access' : 'revdelete-modify-no-access';
                                $itemStatus->error( $msg, $item->formatDate(), $item->formatTime() );
                                $status->failCount++;
                                continue;
                        // Cannot just "hide from Sysops" without hiding any fields
                        } elseif ( $newBits == Revision::DELETED_RESTRICTED ) {
                                $itemStatus->warning(
                                        'revdelete-only-restricted', $item->formatDate(), $item->formatTime() );
                                $status->failCount++;
                                continue;
                        }

                        // Update the revision
                        $ok = $item->setBits( $newBits );

                        if ( $ok ) {
                                $idsForLog[] = $item->getId();
                                // If any item field was suppressed or unsupressed
                                if ( ( $oldBits | $newBits ) & $this->getSuppressBit() ) {
                                        $logType = 'suppress';
                                }
                                // Track which fields where (un)hidden for each item
                                $addedBits = ( $oldBits ^ $newBits ) & $newBits;
                                $removedBits = ( $oldBits ^ $newBits ) & $oldBits;
                                $virtualNewBits |= $addedBits;
                                $virtualOldBits |= $removedBits;

                                $status->successCount++;
                                if ( $item->getAuthorId() > 0 ) {
                                        $authorIds[] = $item->getAuthorId();
                                } elseif ( IP::isIPAddress( $item->getAuthorName() ) ) {
                                        $authorIPs[] = $item->getAuthorName();
                                }

                                // Save the old and new bits in $visibilityChangeMap for
                                // later use.
                                $visibilityChangeMap[$item->getId()] = [
                                        'oldBits' => $oldBits,
                                        'newBits' => $newBits,
                                ];
                        } else {
                                $itemStatus->error(
                                        'revdelete-concurrent-change', $item->formatDate(), $item->formatTime() );
                                $status->failCount++;
                        }
                }

                // Handle missing revisions
                foreach ( $missing as $id => $unused ) {
                        if ( $perItemStatus ) {
                                $status->itemStatuses[$id] = Status::newFatal( 'revdelete-modify-missing', $id );
                        } else {
                                $status->error( 'revdelete-modify-missing', $id );
                        }
                        $status->failCount++;
                }

                if ( $status->successCount == 0 ) {
                        $dbw->endAtomic( __METHOD__ );
                        return $status;
                }

                // Save success count
                $successCount = $status->successCount;

                // Move files, if there are any
                $status->merge( $this->doPreCommitUpdates() );
                if ( !$status->isOK() ) {
                        // Fatal error, such as no configured archive directory or I/O failures
                        $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
                        $lbFactory->rollbackMasterChanges( __METHOD__ );
                        return $status;
                }

                // Log it
                $this->updateLog(
                        $logType,
                        [
                                'title' => $this->title,
                                'count' => $successCount,
                                'newBits' => $virtualNewBits,
                                'oldBits' => $virtualOldBits,
                                'comment' => $comment,
                                'ids' => $idsForLog,
                                'authorIds' => $authorIds,
                                'authorIPs' => $authorIPs,
                                'tags' => isset( $params['tags'] ) ? $params['tags'] : [],
                        ]
                );

                // Clear caches after commit
                DeferredUpdates::addCallableUpdate(
                        function () use ( $visibilityChangeMap ) {
                                $this->doPostCommitUpdates( $visibilityChangeMap );
                        },
                        DeferredUpdates::PRESEND,
                        $dbw
                );

                $dbw->endAtomic( __METHOD__ );

                return $status;
        }

        final protected function acquireItemLocks() {
                $status = Status::newGood();
                /** @var $item RevDelItem */
                foreach ( $this as $item ) {
                        $status->merge( $item->lock() );
                }

                return $status;
        }

        final protected function releaseItemLocks() {
                $status = Status::newGood();
                /** @var $item RevDelItem */
                foreach ( $this as $item ) {
                        $status->merge( $item->unlock() );
                }

                return $status;
        }

        /**
         * Reload the list data from the master DB. This can be done after setVisibility()
         * to allow $item->getHTML() to show the new data.
         */
        function reloadFromMaster() {
                $dbw = wfGetDB( DB_MASTER );
                $this->res = $this->doQuery( $dbw );
        }

        /**
         * Record a log entry on the action
         * @param string $logType One of (delete,suppress)
         * @param array $params Associative array of parameters:
         *     newBits:         The new value of the *_deleted bitfield
         *     oldBits:         The old value of the *_deleted bitfield.
         *     title:           The target title
         *     ids:             The ID list
         *     comment:         The log comment
         *     authorsIds:      The array of the user IDs of the offenders
         *     authorsIPs:      The array of the IP/anon user offenders
         *     tags:            The array of change tags to apply to the log entry
         * @throws MWException
         */
        private function updateLog( $logType, $params ) {
                // Get the URL param's corresponding DB field
                $field = RevisionDeleter::getRelationType( $this->getType() );
                if ( !$field ) {
                        throw new MWException( "Bad log URL param type!" );
                }
                // Add params for affected page and ids
                $logParams = $this->getLogParams( $params );
                // Actually add the deletion log entry
                $logEntry = new ManualLogEntry( $logType, $this->getLogAction() );
                $logEntry->setTarget( $params['title'] );
                $logEntry->setComment( $params['comment'] );
                $logEntry->setParameters( $logParams );
                $logEntry->setPerformer( $this->getUser() );
                // Allow for easy searching of deletion log items for revision/log items
                $logEntry->setRelations( [
                        $field => $params['ids'],
                        'target_author_id' => $params['authorIds'],
                        'target_author_ip' => $params['authorIPs'],
                ] );
                // Apply change tags to the log entry
                $logEntry->setTags( $params['tags'] );
                $logId = $logEntry->insert();
                $logEntry->publish( $logId );
        }

        /**
         * Get the log action for this list type
         * @return string
         */
        public function getLogAction() {
                return 'revision';
        }

        /**
         * Get log parameter array.
         * @param array $params Associative array of log parameters, same as updateLog()
         * @return array
         */
        public function getLogParams( $params ) {
                return [
                        '4::type' => $this->getType(),
                        '5::ids' => $params['ids'],
                        '6::ofield' => $params['oldBits'],
                        '7::nfield' => $params['newBits'],
                ];
        }

        /**
         * Clear any data structures needed for doPreCommitUpdates() and doPostCommitUpdates()
         * STUB
         */
        public function clearFileOps() {
        }

        /**
         * A hook for setVisibility(): do batch updates pre-commit.
         * STUB
         * @return Status
         */
        public function doPreCommitUpdates() {
                return Status::newGood();
        }

        /**
         * A hook for setVisibility(): do any necessary updates post-commit.
         * STUB
         * @param array [id => ['oldBits' => $oldBits, 'newBits' => $newBits], ... ]
         * @return Status
         */
        public function doPostCommitUpdates( array $visibilityChangeMap ) {
                return Status::newGood();
        }

        /**
         * Get the integer value of the flag used for suppression
         */
        abstract public function getSuppressBit();
}