wikimedia/mediawiki-core

<?php
/**
 * Helper class for representing operations with transaction support.
 *
 * 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 FileBackend
 */

use Wikimedia\FileBackend\FileBackend;

/**
 * Move a file from one storage path to another in the backend.
 * Parameters for this operation are outlined in FileBackend::doOperations().
 */
class MoveFileOp extends FileOp {
    protected function allowedParams() {
        return [
            [ 'src', 'dst' ],
            [ 'overwrite', 'overwriteSame', 'ignoreMissingSource', 'headers' ],
            [ 'src', 'dst' ]
        ];
    }

    protected function doPrecheck(
        FileStatePredicates $opPredicates,
        FileStatePredicates $batchPredicates
    ) {
        $status = StatusValue::newGood();

        // Check source file existence
        $srcExists = $this->resolveFileExistence( $this->params['src'], $opPredicates );
        if ( $srcExists === false ) {
            if ( $this->getParam( 'ignoreMissingSource' ) ) {
                $this->noOp = true; // no-op
                // Update file existence predicates (cache 404s)
                $batchPredicates->assumeFileDoesNotExist( $this->params['src'] );

                return $status; // nothing to do
            } else {
                $status->fatal( 'backend-fail-notexists', $this->params['src'] );

                return $status;
            }
        } elseif ( $srcExists === FileBackend::EXISTENCE_ERROR ) {
            $status->fatal( 'backend-fail-stat', $this->params['src'] );

            return $status;
        }
        // Check if an incompatible destination file exists
        $srcSize = function () use ( $opPredicates ) {
            static $size = null;
            $size ??= $this->resolveFileSize( $this->params['src'], $opPredicates );
            return $size;
        };
        $srcSha1 = function () use ( $opPredicates ) {
            static $sha1 = null;
            $sha1 ??= $this->resolveFileSha1Base36( $this->params['src'], $opPredicates );
            return $sha1;
        };
        $status->merge( $this->precheckDestExistence( $opPredicates, $srcSize, $srcSha1 ) );
        $this->params['dstExists'] = $this->destExists; // see FileBackendStore::setFileCache()

        // Update file existence predicates if the operation is expected to be allowed to run
        if ( $status->isOK() ) {
            $batchPredicates->assumeFileExists( $this->params['dst'], $srcSize, $srcSha1 );
            if ( $this->params['src'] !== $this->params['dst'] ) {
                $batchPredicates->assumeFileDoesNotExist( $this->params['src'] );
            }
        }

        return $status; // safe to call attempt()
    }

    protected function doAttempt() {
        if ( $this->overwriteSameCase ) {
            if ( $this->params['src'] === $this->params['dst'] ) {
                // Do nothing to the destination (which is also the source)
                $status = StatusValue::newGood();
            } else {
                // Just delete the source as the destination file needs no changes
                $status = $this->backend->deleteInternal( $this->setFlags(
                    [ 'src' => $this->params['src'] ]
                ) );
            }
        } elseif ( $this->params['src'] === $this->params['dst'] ) {
            // Just update the destination file headers
            $headers = $this->getParam( 'headers' ) ?: [];
            $status = $this->backend->describeInternal( $this->setFlags(
                [ 'src' => $this->params['dst'], 'headers' => $headers ]
            ) );
        } else {
            // Move the file to the destination
            $status = $this->backend->moveInternal( $this->setFlags( $this->params ) );
        }

        return $status;
    }

    public function storagePathsRead() {
        return [ $this->params['src'] ];
    }

    public function storagePathsChanged() {
        return [ $this->params['src'], $this->params['dst'] ];
    }
}