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authorPierre Schmitz <pierre@archlinux.de>2013-01-18 16:46:04 +0100
committerPierre Schmitz <pierre@archlinux.de>2013-01-18 16:46:04 +0100
commit63601400e476c6cf43d985f3e7b9864681695ed4 (patch)
treef7846203a952e38aaf66989d0a4702779f549962 /includes/filebackend/FileOp.php
parent8ff01378c9e0207f9169b81966a51def645b6a51 (diff)
Update to MediaWiki 1.20.2
this update includes: * adjusted Arch Linux skin * updated FluxBBAuthPlugin * patch for https://bugzilla.wikimedia.org/show_bug.cgi?id=44024
Diffstat (limited to 'includes/filebackend/FileOp.php')
-rw-r--r--includes/filebackend/FileOp.php764
1 files changed, 764 insertions, 0 deletions
diff --git a/includes/filebackend/FileOp.php b/includes/filebackend/FileOp.php
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+++ b/includes/filebackend/FileOp.php
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+<?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
+ * @author Aaron Schulz
+ */
+
+/**
+ * FileBackend helper class for representing operations.
+ * Do not use this class from places outside FileBackend.
+ *
+ * Methods called from FileOpBatch::attempt() should avoid throwing
+ * exceptions at all costs. FileOp objects should be lightweight in order
+ * to support large arrays in memory and serialization.
+ *
+ * @ingroup FileBackend
+ * @since 1.19
+ */
+abstract class FileOp {
+ /** @var Array */
+ protected $params = array();
+ /** @var FileBackendStore */
+ protected $backend;
+
+ protected $state = self::STATE_NEW; // integer
+ protected $failed = false; // boolean
+ protected $async = false; // boolean
+ protected $useLatest = true; // boolean
+ protected $batchId; // string
+
+ protected $sourceSha1; // string
+ protected $destSameAsSource; // boolean
+
+ /* Object life-cycle */
+ const STATE_NEW = 1;
+ const STATE_CHECKED = 2;
+ const STATE_ATTEMPTED = 3;
+
+ /**
+ * Build a new file operation transaction
+ *
+ * @param $backend FileBackendStore
+ * @param $params Array
+ * @throws MWException
+ */
+ final public function __construct( FileBackendStore $backend, array $params ) {
+ $this->backend = $backend;
+ list( $required, $optional ) = $this->allowedParams();
+ foreach ( $required as $name ) {
+ if ( isset( $params[$name] ) ) {
+ $this->params[$name] = $params[$name];
+ } else {
+ throw new MWException( "File operation missing parameter '$name'." );
+ }
+ }
+ foreach ( $optional as $name ) {
+ if ( isset( $params[$name] ) ) {
+ $this->params[$name] = $params[$name];
+ }
+ }
+ $this->params = $params;
+ }
+
+ /**
+ * Set the batch UUID this operation belongs to
+ *
+ * @param $batchId string
+ * @return void
+ */
+ final public function setBatchId( $batchId ) {
+ $this->batchId = $batchId;
+ }
+
+ /**
+ * Whether to allow stale data for file reads and stat checks
+ *
+ * @param $allowStale bool
+ * @return void
+ */
+ final public function allowStaleReads( $allowStale ) {
+ $this->useLatest = !$allowStale;
+ }
+
+ /**
+ * Get the value of the parameter with the given name
+ *
+ * @param $name string
+ * @return mixed Returns null if the parameter is not set
+ */
+ final public function getParam( $name ) {
+ return isset( $this->params[$name] ) ? $this->params[$name] : null;
+ }
+
+ /**
+ * Check if this operation failed precheck() or attempt()
+ *
+ * @return bool
+ */
+ final public function failed() {
+ return $this->failed;
+ }
+
+ /**
+ * Get a new empty predicates array for precheck()
+ *
+ * @return Array
+ */
+ final public static function newPredicates() {
+ return array( 'exists' => array(), 'sha1' => array() );
+ }
+
+ /**
+ * Get a new empty dependency tracking array for paths read/written to
+ *
+ * @return Array
+ */
+ final public static function newDependencies() {
+ return array( 'read' => array(), 'write' => array() );
+ }
+
+ /**
+ * Update a dependency tracking array to account for this operation
+ *
+ * @param $deps Array Prior path reads/writes; format of FileOp::newPredicates()
+ * @return Array
+ */
+ final public function applyDependencies( array $deps ) {
+ $deps['read'] += array_fill_keys( $this->storagePathsRead(), 1 );
+ $deps['write'] += array_fill_keys( $this->storagePathsChanged(), 1 );
+ return $deps;
+ }
+
+ /**
+ * Check if this operation changes files listed in $paths
+ *
+ * @param $paths Array Prior path reads/writes; format of FileOp::newPredicates()
+ * @return boolean
+ */
+ final public function dependsOn( array $deps ) {
+ foreach ( $this->storagePathsChanged() as $path ) {
+ if ( isset( $deps['read'][$path] ) || isset( $deps['write'][$path] ) ) {
+ return true; // "output" or "anti" dependency
+ }
+ }
+ foreach ( $this->storagePathsRead() as $path ) {
+ if ( isset( $deps['write'][$path] ) ) {
+ return true; // "flow" dependency
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Get the file journal entries for this file operation
+ *
+ * @param $oPredicates Array Pre-op info about files (format of FileOp::newPredicates)
+ * @param $nPredicates Array Post-op info about files (format of FileOp::newPredicates)
+ * @return Array
+ */
+ final public function getJournalEntries( array $oPredicates, array $nPredicates ) {
+ $nullEntries = array();
+ $updateEntries = array();
+ $deleteEntries = array();
+ $pathsUsed = array_merge( $this->storagePathsRead(), $this->storagePathsChanged() );
+ foreach ( $pathsUsed as $path ) {
+ $nullEntries[] = array( // assertion for recovery
+ 'op' => 'null',
+ 'path' => $path,
+ 'newSha1' => $this->fileSha1( $path, $oPredicates )
+ );
+ }
+ foreach ( $this->storagePathsChanged() as $path ) {
+ if ( $nPredicates['sha1'][$path] === false ) { // deleted
+ $deleteEntries[] = array(
+ 'op' => 'delete',
+ 'path' => $path,
+ 'newSha1' => ''
+ );
+ } else { // created/updated
+ $updateEntries[] = array(
+ 'op' => $this->fileExists( $path, $oPredicates ) ? 'update' : 'create',
+ 'path' => $path,
+ 'newSha1' => $nPredicates['sha1'][$path]
+ );
+ }
+ }
+ return array_merge( $nullEntries, $updateEntries, $deleteEntries );
+ }
+
+ /**
+ * Check preconditions of the operation without writing anything
+ *
+ * @param $predicates Array
+ * @return Status
+ */
+ final public function precheck( array &$predicates ) {
+ if ( $this->state !== self::STATE_NEW ) {
+ return Status::newFatal( 'fileop-fail-state', self::STATE_NEW, $this->state );
+ }
+ $this->state = self::STATE_CHECKED;
+ $status = $this->doPrecheck( $predicates );
+ if ( !$status->isOK() ) {
+ $this->failed = true;
+ }
+ return $status;
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doPrecheck( array &$predicates ) {
+ return Status::newGood();
+ }
+
+ /**
+ * Attempt the operation
+ *
+ * @return Status
+ */
+ final public function attempt() {
+ if ( $this->state !== self::STATE_CHECKED ) {
+ return Status::newFatal( 'fileop-fail-state', self::STATE_CHECKED, $this->state );
+ } elseif ( $this->failed ) { // failed precheck
+ return Status::newFatal( 'fileop-fail-attempt-precheck' );
+ }
+ $this->state = self::STATE_ATTEMPTED;
+ $status = $this->doAttempt();
+ if ( !$status->isOK() ) {
+ $this->failed = true;
+ $this->logFailure( 'attempt' );
+ }
+ return $status;
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ return Status::newGood();
+ }
+
+ /**
+ * Attempt the operation in the background
+ *
+ * @return Status
+ */
+ final public function attemptAsync() {
+ $this->async = true;
+ $result = $this->attempt();
+ $this->async = false;
+ return $result;
+ }
+
+ /**
+ * Get the file operation parameters
+ *
+ * @return Array (required params list, optional params list)
+ */
+ protected function allowedParams() {
+ return array( array(), array() );
+ }
+
+ /**
+ * Adjust params to FileBackendStore internal file calls
+ *
+ * @param $params Array
+ * @return Array (required params list, optional params list)
+ */
+ protected function setFlags( array $params ) {
+ return array( 'async' => $this->async ) + $params;
+ }
+
+ /**
+ * Get a list of storage paths read from for this operation
+ *
+ * @return Array
+ */
+ final public function storagePathsRead() {
+ return array_map( 'FileBackend::normalizeStoragePath', $this->doStoragePathsRead() );
+ }
+
+ /**
+ * @see FileOp::storagePathsRead()
+ * @return Array
+ */
+ protected function doStoragePathsRead() {
+ return array();
+ }
+
+ /**
+ * Get a list of storage paths written to for this operation
+ *
+ * @return Array
+ */
+ final public function storagePathsChanged() {
+ return array_map( 'FileBackend::normalizeStoragePath', $this->doStoragePathsChanged() );
+ }
+
+ /**
+ * @see FileOp::storagePathsChanged()
+ * @return Array
+ */
+ protected function doStoragePathsChanged() {
+ return array();
+ }
+
+ /**
+ * Check for errors with regards to the destination file already existing.
+ * This also updates the destSameAsSource and sourceSha1 member variables.
+ * A bad status will be returned if there is no chance it can be overwritten.
+ *
+ * @param $predicates Array
+ * @return Status
+ */
+ protected function precheckDestExistence( array $predicates ) {
+ $status = Status::newGood();
+ // Get hash of source file/string and the destination file
+ $this->sourceSha1 = $this->getSourceSha1Base36(); // FS file or data string
+ if ( $this->sourceSha1 === null ) { // file in storage?
+ $this->sourceSha1 = $this->fileSha1( $this->params['src'], $predicates );
+ }
+ $this->destSameAsSource = false;
+ if ( $this->fileExists( $this->params['dst'], $predicates ) ) {
+ if ( $this->getParam( 'overwrite' ) ) {
+ return $status; // OK
+ } elseif ( $this->getParam( 'overwriteSame' ) ) {
+ $dhash = $this->fileSha1( $this->params['dst'], $predicates );
+ // Check if hashes are valid and match each other...
+ if ( !strlen( $this->sourceSha1 ) || !strlen( $dhash ) ) {
+ $status->fatal( 'backend-fail-hashes' );
+ } elseif ( $this->sourceSha1 !== $dhash ) {
+ // Give an error if the files are not identical
+ $status->fatal( 'backend-fail-notsame', $this->params['dst'] );
+ } else {
+ $this->destSameAsSource = true; // OK
+ }
+ return $status; // do nothing; either OK or bad status
+ } else {
+ $status->fatal( 'backend-fail-alreadyexists', $this->params['dst'] );
+ return $status;
+ }
+ }
+ return $status;
+ }
+
+ /**
+ * precheckDestExistence() helper function to get the source file SHA-1.
+ * Subclasses should overwride this iff the source is not in storage.
+ *
+ * @return string|bool Returns false on failure
+ */
+ protected function getSourceSha1Base36() {
+ return null; // N/A
+ }
+
+ /**
+ * Check if a file will exist in storage when this operation is attempted
+ *
+ * @param $source string Storage path
+ * @param $predicates Array
+ * @return bool
+ */
+ final protected function fileExists( $source, array $predicates ) {
+ if ( isset( $predicates['exists'][$source] ) ) {
+ return $predicates['exists'][$source]; // previous op assures this
+ } else {
+ $params = array( 'src' => $source, 'latest' => $this->useLatest );
+ return $this->backend->fileExists( $params );
+ }
+ }
+
+ /**
+ * Get the SHA-1 of a file in storage when this operation is attempted
+ *
+ * @param $source string Storage path
+ * @param $predicates Array
+ * @return string|bool False on failure
+ */
+ final protected function fileSha1( $source, array $predicates ) {
+ if ( isset( $predicates['sha1'][$source] ) ) {
+ return $predicates['sha1'][$source]; // previous op assures this
+ } else {
+ $params = array( 'src' => $source, 'latest' => $this->useLatest );
+ return $this->backend->getFileSha1Base36( $params );
+ }
+ }
+
+ /**
+ * Get the backend this operation is for
+ *
+ * @return FileBackendStore
+ */
+ public function getBackend() {
+ return $this->backend;
+ }
+
+ /**
+ * Log a file operation failure and preserve any temp files
+ *
+ * @param $action string
+ * @return void
+ */
+ final public function logFailure( $action ) {
+ $params = $this->params;
+ $params['failedAction'] = $action;
+ try {
+ wfDebugLog( 'FileOperation', get_class( $this ) .
+ " failed (batch #{$this->batchId}): " . FormatJson::encode( $params ) );
+ } catch ( Exception $e ) {
+ // bad config? debug log error?
+ }
+ }
+}
+
+/**
+ * Store a file into the backend from a file on the file system.
+ * Parameters for this operation are outlined in FileBackend::doOperations().
+ */
+class StoreFileOp extends FileOp {
+ /**
+ * @return array
+ */
+ protected function allowedParams() {
+ return array( array( 'src', 'dst' ),
+ array( 'overwrite', 'overwriteSame', 'disposition' ) );
+ }
+
+ /**
+ * @param $predicates array
+ * @return Status
+ */
+ protected function doPrecheck( array &$predicates ) {
+ $status = Status::newGood();
+ // Check if the source file exists on the file system
+ if ( !is_file( $this->params['src'] ) ) {
+ $status->fatal( 'backend-fail-notexists', $this->params['src'] );
+ return $status;
+ // Check if the source file is too big
+ } elseif ( filesize( $this->params['src'] ) > $this->backend->maxFileSizeInternal() ) {
+ $status->fatal( 'backend-fail-maxsize',
+ $this->params['dst'], $this->backend->maxFileSizeInternal() );
+ $status->fatal( 'backend-fail-store', $this->params['src'], $this->params['dst'] );
+ return $status;
+ // Check if a file can be placed at the destination
+ } elseif ( !$this->backend->isPathUsableInternal( $this->params['dst'] ) ) {
+ $status->fatal( 'backend-fail-usable', $this->params['dst'] );
+ $status->fatal( 'backend-fail-store', $this->params['src'], $this->params['dst'] );
+ return $status;
+ }
+ // Check if destination file exists
+ $status->merge( $this->precheckDestExistence( $predicates ) );
+ if ( $status->isOK() ) {
+ // Update file existence predicates
+ $predicates['exists'][$this->params['dst']] = true;
+ $predicates['sha1'][$this->params['dst']] = $this->sourceSha1;
+ }
+ return $status; // safe to call attempt()
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ // Store the file at the destination
+ if ( !$this->destSameAsSource ) {
+ return $this->backend->storeInternal( $this->setFlags( $this->params ) );
+ }
+ return Status::newGood();
+ }
+
+ /**
+ * @return bool|string
+ */
+ protected function getSourceSha1Base36() {
+ wfSuppressWarnings();
+ $hash = sha1_file( $this->params['src'] );
+ wfRestoreWarnings();
+ if ( $hash !== false ) {
+ $hash = wfBaseConvert( $hash, 16, 36, 31 );
+ }
+ return $hash;
+ }
+
+ protected function doStoragePathsChanged() {
+ return array( $this->params['dst'] );
+ }
+}
+
+/**
+ * Create a file in the backend with the given content.
+ * Parameters for this operation are outlined in FileBackend::doOperations().
+ */
+class CreateFileOp extends FileOp {
+ protected function allowedParams() {
+ return array( array( 'content', 'dst' ),
+ array( 'overwrite', 'overwriteSame', 'disposition' ) );
+ }
+
+ protected function doPrecheck( array &$predicates ) {
+ $status = Status::newGood();
+ // Check if the source data is too big
+ if ( strlen( $this->getParam( 'content' ) ) > $this->backend->maxFileSizeInternal() ) {
+ $status->fatal( 'backend-fail-maxsize',
+ $this->params['dst'], $this->backend->maxFileSizeInternal() );
+ $status->fatal( 'backend-fail-create', $this->params['dst'] );
+ return $status;
+ // Check if a file can be placed at the destination
+ } elseif ( !$this->backend->isPathUsableInternal( $this->params['dst'] ) ) {
+ $status->fatal( 'backend-fail-usable', $this->params['dst'] );
+ $status->fatal( 'backend-fail-create', $this->params['dst'] );
+ return $status;
+ }
+ // Check if destination file exists
+ $status->merge( $this->precheckDestExistence( $predicates ) );
+ if ( $status->isOK() ) {
+ // Update file existence predicates
+ $predicates['exists'][$this->params['dst']] = true;
+ $predicates['sha1'][$this->params['dst']] = $this->sourceSha1;
+ }
+ return $status; // safe to call attempt()
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ if ( !$this->destSameAsSource ) {
+ // Create the file at the destination
+ return $this->backend->createInternal( $this->setFlags( $this->params ) );
+ }
+ return Status::newGood();
+ }
+
+ /**
+ * @return bool|String
+ */
+ protected function getSourceSha1Base36() {
+ return wfBaseConvert( sha1( $this->params['content'] ), 16, 36, 31 );
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsChanged() {
+ return array( $this->params['dst'] );
+ }
+}
+
+/**
+ * Copy a file from one storage path to another in the backend.
+ * Parameters for this operation are outlined in FileBackend::doOperations().
+ */
+class CopyFileOp extends FileOp {
+ /**
+ * @return array
+ */
+ protected function allowedParams() {
+ return array( array( 'src', 'dst' ),
+ array( 'overwrite', 'overwriteSame', 'disposition' ) );
+ }
+
+ /**
+ * @param $predicates array
+ * @return Status
+ */
+ protected function doPrecheck( array &$predicates ) {
+ $status = Status::newGood();
+ // Check if the source file exists
+ if ( !$this->fileExists( $this->params['src'], $predicates ) ) {
+ $status->fatal( 'backend-fail-notexists', $this->params['src'] );
+ return $status;
+ // Check if a file can be placed at the destination
+ } elseif ( !$this->backend->isPathUsableInternal( $this->params['dst'] ) ) {
+ $status->fatal( 'backend-fail-usable', $this->params['dst'] );
+ $status->fatal( 'backend-fail-copy', $this->params['src'], $this->params['dst'] );
+ return $status;
+ }
+ // Check if destination file exists
+ $status->merge( $this->precheckDestExistence( $predicates ) );
+ if ( $status->isOK() ) {
+ // Update file existence predicates
+ $predicates['exists'][$this->params['dst']] = true;
+ $predicates['sha1'][$this->params['dst']] = $this->sourceSha1;
+ }
+ return $status; // safe to call attempt()
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ // Do nothing if the src/dst paths are the same
+ if ( $this->params['src'] !== $this->params['dst'] ) {
+ // Copy the file into the destination
+ if ( !$this->destSameAsSource ) {
+ return $this->backend->copyInternal( $this->setFlags( $this->params ) );
+ }
+ }
+ return Status::newGood();
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsRead() {
+ return array( $this->params['src'] );
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsChanged() {
+ return array( $this->params['dst'] );
+ }
+}
+
+/**
+ * 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 {
+ /**
+ * @return array
+ */
+ protected function allowedParams() {
+ return array( array( 'src', 'dst' ),
+ array( 'overwrite', 'overwriteSame', 'disposition' ) );
+ }
+
+ /**
+ * @param $predicates array
+ * @return Status
+ */
+ protected function doPrecheck( array &$predicates ) {
+ $status = Status::newGood();
+ // Check if the source file exists
+ if ( !$this->fileExists( $this->params['src'], $predicates ) ) {
+ $status->fatal( 'backend-fail-notexists', $this->params['src'] );
+ return $status;
+ // Check if a file can be placed at the destination
+ } elseif ( !$this->backend->isPathUsableInternal( $this->params['dst'] ) ) {
+ $status->fatal( 'backend-fail-usable', $this->params['dst'] );
+ $status->fatal( 'backend-fail-move', $this->params['src'], $this->params['dst'] );
+ return $status;
+ }
+ // Check if destination file exists
+ $status->merge( $this->precheckDestExistence( $predicates ) );
+ if ( $status->isOK() ) {
+ // Update file existence predicates
+ $predicates['exists'][$this->params['src']] = false;
+ $predicates['sha1'][$this->params['src']] = false;
+ $predicates['exists'][$this->params['dst']] = true;
+ $predicates['sha1'][$this->params['dst']] = $this->sourceSha1;
+ }
+ return $status; // safe to call attempt()
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ // Do nothing if the src/dst paths are the same
+ if ( $this->params['src'] !== $this->params['dst'] ) {
+ if ( !$this->destSameAsSource ) {
+ // Move the file into the destination
+ return $this->backend->moveInternal( $this->setFlags( $this->params ) );
+ } else {
+ // Just delete source as the destination needs no changes
+ $params = array( 'src' => $this->params['src'] );
+ return $this->backend->deleteInternal( $this->setFlags( $params ) );
+ }
+ }
+ return Status::newGood();
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsRead() {
+ return array( $this->params['src'] );
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsChanged() {
+ return array( $this->params['src'], $this->params['dst'] );
+ }
+}
+
+/**
+ * Delete a file at the given storage path from the backend.
+ * Parameters for this operation are outlined in FileBackend::doOperations().
+ */
+class DeleteFileOp extends FileOp {
+ /**
+ * @return array
+ */
+ protected function allowedParams() {
+ return array( array( 'src' ), array( 'ignoreMissingSource' ) );
+ }
+
+ protected $needsDelete = true;
+
+ /**
+ * @param array $predicates
+ * @return Status
+ */
+ protected function doPrecheck( array &$predicates ) {
+ $status = Status::newGood();
+ // Check if the source file exists
+ if ( !$this->fileExists( $this->params['src'], $predicates ) ) {
+ if ( !$this->getParam( 'ignoreMissingSource' ) ) {
+ $status->fatal( 'backend-fail-notexists', $this->params['src'] );
+ return $status;
+ }
+ $this->needsDelete = false;
+ }
+ // Update file existence predicates
+ $predicates['exists'][$this->params['src']] = false;
+ $predicates['sha1'][$this->params['src']] = false;
+ return $status; // safe to call attempt()
+ }
+
+ /**
+ * @return Status
+ */
+ protected function doAttempt() {
+ if ( $this->needsDelete ) {
+ // Delete the source file
+ return $this->backend->deleteInternal( $this->setFlags( $this->params ) );
+ }
+ return Status::newGood();
+ }
+
+ /**
+ * @return array
+ */
+ protected function doStoragePathsChanged() {
+ return array( $this->params['src'] );
+ }
+}
+
+/**
+ * Placeholder operation that has no params and does nothing
+ */
+class NullFileOp extends FileOp {}