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-rw-r--r--includes/filerepo/backend/FileOp.php697
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diff --git a/includes/filerepo/backend/FileOp.php b/includes/filerepo/backend/FileOp.php
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index 5844c9f2..00000000
--- a/includes/filerepo/backend/FileOp.php
+++ /dev/null
@@ -1,697 +0,0 @@
-<?php
-/**
- * @file
- * @ingroup FileBackend
- * @author Aaron Schulz
- */
-
-/**
- * Helper class for representing operations with transaction support.
- * Do not use this class from places outside FileBackend.
- *
- * Methods called from attemptBatch() should avoid throwing exceptions at all costs.
- * FileOp objects should be lightweight in order to support large arrays in memory.
- *
- * @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 $useLatest = true; // boolean
-
- protected $sourceSha1; // string
- protected $destSameAsSource; // boolean
-
- /* Object life-cycle */
- const STATE_NEW = 1;
- const STATE_CHECKED = 2;
- const STATE_ATTEMPTED = 3;
-
- /* Timeout related parameters */
- const MAX_BATCH_SIZE = 1000;
- const TIME_LIMIT_SEC = 300; // 5 minutes
-
- /**
- * Build a new file operation transaction
- *
- * @params $backend FileBackendStore
- * @params $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;
- }
-
- /**
- * Allow stale data for file reads and existence checks
- *
- * @return void
- */
- final protected function allowStaleReads() {
- $this->useLatest = false;
- }
-
- /**
- * Attempt a series of file operations.
- * Callers are responsible for handling file locking.
- *
- * $opts is an array of options, including:
- * 'force' : Errors that would normally cause a rollback do not.
- * The remaining operations are still attempted if any fail.
- * 'allowStale' : Don't require the latest available data.
- * This can increase performance for non-critical writes.
- * This has no effect unless the 'force' flag is set.
- *
- * The resulting Status will be "OK" unless:
- * a) unexpected operation errors occurred (network partitions, disk full...)
- * b) significant operation errors occured and 'force' was not set
- *
- * @param $performOps Array List of FileOp operations
- * @param $opts Array Batch operation options
- * @return Status
- */
- final public static function attemptBatch( array $performOps, array $opts ) {
- $status = Status::newGood();
-
- $allowStale = !empty( $opts['allowStale'] );
- $ignoreErrors = !empty( $opts['force'] );
-
- $n = count( $performOps );
- if ( $n > self::MAX_BATCH_SIZE ) {
- $status->fatal( 'backend-fail-batchsize', $n, self::MAX_BATCH_SIZE );
- return $status;
- }
-
- $predicates = FileOp::newPredicates(); // account for previous op in prechecks
- // Do pre-checks for each operation; abort on failure...
- foreach ( $performOps as $index => $fileOp ) {
- if ( $allowStale ) {
- $fileOp->allowStaleReads(); // allow potentially stale reads
- }
- $subStatus = $fileOp->precheck( $predicates );
- $status->merge( $subStatus );
- if ( !$subStatus->isOK() ) { // operation failed?
- $status->success[$index] = false;
- ++$status->failCount;
- if ( !$ignoreErrors ) {
- return $status; // abort
- }
- }
- }
-
- if ( $ignoreErrors ) {
- # Treat all precheck() fatals as merely warnings
- $status->setResult( true, $status->value );
- }
-
- // Restart PHP's execution timer and set the timeout to safe amount.
- // This handles cases where the operations take a long time or where we are
- // already running low on time left. The old timeout is restored afterwards.
- # @TODO: re-enable this for when the number of batches is high.
- #$scopedTimeLimit = new FileOpScopedPHPTimeout( self::TIME_LIMIT_SEC );
-
- // Attempt each operation...
- foreach ( $performOps as $index => $fileOp ) {
- if ( $fileOp->failed() ) {
- continue; // nothing to do
- }
- $subStatus = $fileOp->attempt();
- $status->merge( $subStatus );
- if ( $subStatus->isOK() ) {
- $status->success[$index] = true;
- ++$status->successCount;
- } else {
- $status->success[$index] = false;
- ++$status->failCount;
- // We can't continue (even with $ignoreErrors) as $predicates is wrong.
- // Log the remaining ops as failed for recovery...
- for ( $i = ($index + 1); $i < count( $performOps ); $i++ ) {
- $performOps[$i]->logFailure( 'attempt_aborted' );
- }
- return $status; // bail out
- }
- }
-
- return $status;
- }
-
- /**
- * 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() );
- }
-
- /**
- * 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;
- }
-
- /**
- * Attempt the operation, backing up files as needed; this must be reversible
- *
- * @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 $status;
- }
-
- /**
- * Get the file operation parameters
- *
- * @return Array (required params list, optional params list)
- */
- protected function allowedParams() {
- return array( array(), array() );
- }
-
- /**
- * Get a list of storage paths read from for this operation
- *
- * @return Array
- */
- public function storagePathsRead() {
- return array();
- }
-
- /**
- * Get a list of storage paths written to for this operation
- *
- * @return Array
- */
- public function storagePathsChanged() {
- return array();
- }
-
- /**
- * @return Status
- */
- protected function doPrecheck( array &$predicates ) {
- return Status::newGood();
- }
-
- /**
- * @return Status
- */
- protected function doAttempt() {
- return Status::newGood();
- }
-
- /**
- * 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|false 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|false
- */
- 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 );
- }
- }
-
- /**
- * Log a file operation failure and preserve any temp files
- *
- * @param $action string
- * @return void
- */
- final protected function logFailure( $action ) {
- $params = $this->params;
- $params['failedAction'] = $action;
- try {
- wfDebugLog( 'FileOperation',
- get_class( $this ) . ' failed:' . serialize( $params ) );
- } catch ( Exception $e ) {
- // bad config? debug log error?
- }
- }
-}
-
-/**
- * FileOp helper class to expand PHP execution time for a function.
- * On construction, set_time_limit() is called and set to $seconds.
- * When the object goes out of scope, the timer is restarted, with
- * the original time limit minus the time the object existed.
- */
-class FileOpScopedPHPTimeout {
- protected $startTime; // float; seconds
- protected $oldTimeout; // integer; seconds
-
- protected static $stackDepth = 0; // integer
- protected static $totalCalls = 0; // integer
- protected static $totalElapsed = 0; // float; seconds
-
- /* Prevent callers in infinite loops from running forever */
- const MAX_TOTAL_CALLS = 1000000;
- const MAX_TOTAL_TIME = 300; // seconds
-
- /**
- * @param $seconds integer
- */
- public function __construct( $seconds ) {
- if ( ini_get( 'max_execution_time' ) > 0 ) { // CLI uses 0
- if ( self::$totalCalls >= self::MAX_TOTAL_CALLS ) {
- trigger_error( "Maximum invocations of " . __CLASS__ . " exceeded." );
- } elseif ( self::$totalElapsed >= self::MAX_TOTAL_TIME ) {
- trigger_error( "Time limit within invocations of " . __CLASS__ . " exceeded." );
- } elseif ( self::$stackDepth > 0 ) { // recursion guard
- trigger_error( "Resursive invocation of " . __CLASS__ . " attempted." );
- } else {
- $this->oldTimeout = ini_set( 'max_execution_time', $seconds );
- $this->startTime = microtime( true );
- ++self::$stackDepth;
- ++self::$totalCalls; // proof against < 1us scopes
- }
- }
- }
-
- /**
- * Restore the original timeout.
- * This does not account for the timer value on __construct().
- */
- public function __destruct() {
- if ( $this->oldTimeout ) {
- $elapsed = microtime( true ) - $this->startTime;
- // Note: a limit of 0 is treated as "forever"
- set_time_limit( max( 1, $this->oldTimeout - (int)$elapsed ) );
- // If each scoped timeout is for less than one second, we end up
- // restoring the original timeout without any decrease in value.
- // Thus web scripts in an infinite loop can run forever unless we
- // take some measures to prevent this. Track total time and calls.
- self::$totalElapsed += $elapsed;
- --self::$stackDepth;
- }
- }
-}
-
-/**
- * Store a file into the backend from a file on the file system.
- * Parameters similar to FileBackendStore::storeInternal(), which include:
- * src : source path on file system
- * dst : destination storage path
- * overwrite : do nothing and pass if an identical file exists at destination
- * overwriteSame : override any existing file at destination
- */
-class StoreFileOp extends FileOp {
- protected function allowedParams() {
- return array( array( 'src', 'dst' ), array( 'overwrite', 'overwriteSame' ) );
- }
-
- 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-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-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()
- }
-
- protected function doAttempt() {
- $status = Status::newGood();
- // Store the file at the destination
- if ( !$this->destSameAsSource ) {
- $status->merge( $this->backend->storeInternal( $this->params ) );
- }
- return $status;
- }
-
- protected function getSourceSha1Base36() {
- wfSuppressWarnings();
- $hash = sha1_file( $this->params['src'] );
- wfRestoreWarnings();
- if ( $hash !== false ) {
- $hash = wfBaseConvert( $hash, 16, 36, 31 );
- }
- return $hash;
- }
-
- public function storagePathsChanged() {
- return array( $this->params['dst'] );
- }
-}
-
-/**
- * Create a file in the backend with the given content.
- * Parameters similar to FileBackendStore::createInternal(), which include:
- * content : the raw file contents
- * dst : destination storage path
- * overwrite : do nothing and pass if an identical file exists at destination
- * overwriteSame : override any existing file at destination
- */
-class CreateFileOp extends FileOp {
- protected function allowedParams() {
- return array( array( 'content', 'dst' ), array( 'overwrite', 'overwriteSame' ) );
- }
-
- protected function doPrecheck( array &$predicates ) {
- $status = Status::newGood();
- // Check if the source data is too big
- if ( strlen( $this->getParam( 'content' ) ) > $this->backend->maxFileSizeInternal() ) {
- $status->fatal( 'backend-fail-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-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()
- }
-
- protected function doAttempt() {
- $status = Status::newGood();
- // Create the file at the destination
- if ( !$this->destSameAsSource ) {
- $status->merge( $this->backend->createInternal( $this->params ) );
- }
- return $status;
- }
-
- protected function getSourceSha1Base36() {
- return wfBaseConvert( sha1( $this->params['content'] ), 16, 36, 31 );
- }
-
- public function storagePathsChanged() {
- return array( $this->params['dst'] );
- }
-}
-
-/**
- * Copy a file from one storage path to another in the backend.
- * Parameters similar to FileBackendStore::copyInternal(), which include:
- * src : source storage path
- * dst : destination storage path
- * overwrite : do nothing and pass if an identical file exists at destination
- * overwriteSame : override any existing file at destination
- */
-class CopyFileOp extends FileOp {
- protected function allowedParams() {
- return array( array( 'src', 'dst' ), array( 'overwrite', 'overwriteSame' ) );
- }
-
- protected function doPrecheck( array &$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-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()
- }
-
- protected function doAttempt() {
- $status = Status::newGood();
- // 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 ) {
- $status->merge( $this->backend->copyInternal( $this->params ) );
- }
- }
- return $status;
- }
-
- public function storagePathsRead() {
- return array( $this->params['src'] );
- }
-
- public function storagePathsChanged() {
- return array( $this->params['dst'] );
- }
-}
-
-/**
- * Move a file from one storage path to another in the backend.
- * Parameters similar to FileBackendStore::moveInternal(), which include:
- * src : source storage path
- * dst : destination storage path
- * overwrite : do nothing and pass if an identical file exists at destination
- * overwriteSame : override any existing file at destination
- */
-class MoveFileOp extends FileOp {
- protected function allowedParams() {
- return array( array( 'src', 'dst' ), array( 'overwrite', 'overwriteSame' ) );
- }
-
- protected function doPrecheck( array &$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-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()
- }
-
- protected function doAttempt() {
- $status = Status::newGood();
- // 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
- $status->merge( $this->backend->moveInternal( $this->params ) );
- } else {
- // Just delete source as the destination needs no changes
- $params = array( 'src' => $this->params['src'] );
- $status->merge( $this->backend->deleteInternal( $params ) );
- }
- }
- return $status;
- }
-
- public function storagePathsRead() {
- return array( $this->params['src'] );
- }
-
- public function storagePathsChanged() {
- return array( $this->params['dst'] );
- }
-}
-
-/**
- * Delete a file at the given storage path from the backend.
- * Parameters similar to FileBackendStore::deleteInternal(), which include:
- * src : source storage path
- * ignoreMissingSource : don't return an error if the file does not exist
- */
-class DeleteFileOp extends FileOp {
- protected function allowedParams() {
- return array( array( 'src' ), array( 'ignoreMissingSource' ) );
- }
-
- protected $needsDelete = true;
-
- protected function doPrecheck( array &$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()
- }
-
- protected function doAttempt() {
- $status = Status::newGood();
- if ( $this->needsDelete ) {
- // Delete the source file
- $status->merge( $this->backend->deleteInternal( $this->params ) );
- }
- return $status;
- }
-
- public function storagePathsChanged() {
- return array( $this->params['src'] );
- }
-}
-
-/**
- * Placeholder operation that has no params and does nothing
- */
-class NullFileOp extends FileOp {}