maintenance/copyFileBackend.php
<?php
/**
* Copy all files in some containers of one backend to another.
*
* 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 Maintenance
*/
use MediaWiki\Status\Status;
require_once __DIR__ . '/Maintenance.php';
/**
* Copy all files in one container of one backend to another.
*
* This can also be used to re-shard the files for one backend using the
* config of second backend. The second backend should have the same config
* as the first, except for it having a different name and different sharding
* configuration. The backend should be made read-only while this runs.
* After this script finishes, the old files in the containers can be deleted.
*
* @ingroup Maintenance
*/
class CopyFileBackend extends Maintenance {
/** @var array|null (path sha1 => stat) Pre-computed dst stat entries from listings */
protected $statCache = null;
public function __construct() {
parent::__construct();
$this->addDescription( 'Copy files in one backend to another.' );
$this->addOption( 'src', 'Backend containing the source files', true, true );
$this->addOption( 'dst', 'Backend where files should be copied to', true, true );
$this->addOption( 'containers', 'Pipe separated list of containers', true, true );
$this->addOption( 'subdir', 'Only do items in this child directory', false, true );
$this->addOption( 'ratefile', 'File to check periodically for batch size', false, true );
$this->addOption( 'prestat', 'Stat the destination files first (try to use listings)' );
$this->addOption( 'skiphash', 'Skip SHA-1 sync checks for files' );
$this->addOption( 'missingonly', 'Only copy files missing from destination listing' );
$this->addOption( 'syncviadelete', 'Delete destination files missing from source listing' );
$this->addOption( 'utf8only', 'Skip source files that do not have valid UTF-8 names' );
$this->setBatchSize( 50 );
}
public function execute() {
$backendGroup = $this->getServiceContainer()->getFileBackendGroup();
$src = $backendGroup->get( $this->getOption( 'src' ) );
$dst = $backendGroup->get( $this->getOption( 'dst' ) );
$containers = explode( '|', $this->getOption( 'containers' ) );
$subDir = rtrim( $this->getOption( 'subdir', '' ), '/' );
$rateFile = $this->getOption( 'ratefile' );
foreach ( $containers as $container ) {
if ( $subDir != '' ) {
$backendRel = "$container/$subDir";
$this->output( "Doing container '$container', directory '$subDir'...\n" );
} else {
$backendRel = $container;
$this->output( "Doing container '$container'...\n" );
}
if ( $this->hasOption( 'missingonly' ) ) {
$this->output( "\tBuilding list of missing files..." );
$srcPathsRel = $this->getListingDiffRel( $src, $dst, $backendRel );
$this->output( count( $srcPathsRel ) . " file(s) need to be copied.\n" );
} else {
$srcPathsRel = $src->getFileList( [
'dir' => $src->getRootStoragePath() . "/$backendRel",
'adviseStat' => true // avoid HEADs
] );
if ( $srcPathsRel === null ) {
$this->fatalError( "Could not list files in $container." );
}
}
if ( $this->getOption( 'prestat' ) && !$this->hasOption( 'missingonly' ) ) {
// Build the stat cache for the destination files
$this->output( "\tBuilding destination stat cache..." );
$dstPathsRel = $dst->getFileList( [
'dir' => $dst->getRootStoragePath() . "/$backendRel",
'adviseStat' => true // avoid HEADs
] );
if ( $dstPathsRel === null ) {
$this->fatalError( "Could not list files in $container." );
}
$this->statCache = [];
foreach ( $dstPathsRel as $dstPathRel ) {
$path = $dst->getRootStoragePath() . "/$backendRel/$dstPathRel";
$this->statCache[sha1( $path )] = $dst->getFileStat( [ 'src' => $path ] );
}
$this->output( "done [" . count( $this->statCache ) . " file(s)]\n" );
}
$this->output( "\tCopying file(s)...\n" );
$count = 0;
$batchPaths = [];
foreach ( $srcPathsRel as $srcPathRel ) {
// Check up on the rate file periodically to adjust the concurrency
if ( $rateFile && ( !$count || ( $count % 500 ) == 0 ) ) {
$this->setBatchSize( max( 1, (int)file_get_contents( $rateFile ) ) );
$this->output( "\tBatch size is now {$this->getBatchSize()}.\n" );
}
$batchPaths[$srcPathRel] = 1; // remove duplicates
if ( count( $batchPaths ) >= $this->getBatchSize() ) {
$this->copyFileBatch( array_keys( $batchPaths ), $backendRel, $src, $dst );
$batchPaths = []; // done
}
++$count;
}
if ( count( $batchPaths ) ) { // left-overs
$this->copyFileBatch( array_keys( $batchPaths ), $backendRel, $src, $dst );
}
$this->output( "\tCopied $count file(s).\n" );
if ( $this->hasOption( 'syncviadelete' ) ) {
$this->output( "\tBuilding list of excess destination files..." );
$delPathsRel = $this->getListingDiffRel( $dst, $src, $backendRel );
$this->output( count( $delPathsRel ) . " file(s) need to be deleted.\n" );
$this->output( "\tDeleting file(s)...\n" );
$count = 0;
$batchPaths = [];
foreach ( $delPathsRel as $delPathRel ) {
// Check up on the rate file periodically to adjust the concurrency
if ( $rateFile && ( !$count || ( $count % 500 ) == 0 ) ) {
$this->setBatchSize( max( 1, (int)file_get_contents( $rateFile ) ) );
$this->output( "\tBatch size is now {$this->getBatchSize()}.\n" );
}
$batchPaths[$delPathRel] = 1; // remove duplicates
if ( count( $batchPaths ) >= $this->getBatchSize() ) {
$this->delFileBatch( array_keys( $batchPaths ), $backendRel, $dst );
$batchPaths = []; // done
}
++$count;
}
if ( count( $batchPaths ) ) { // left-overs
$this->delFileBatch( array_keys( $batchPaths ), $backendRel, $dst );
}
$this->output( "\tDeleted $count file(s).\n" );
}
if ( $subDir != '' ) {
$this->output( "Finished container '$container', directory '$subDir'.\n" );
} else {
$this->output( "Finished container '$container'.\n" );
}
}
$this->output( "Done.\n" );
}
/**
* @param FileBackend $src
* @param FileBackend $dst
* @param string $backendRel
* @return string[] (rel paths in $src minus those in $dst)
*/
protected function getListingDiffRel( FileBackend $src, FileBackend $dst, $backendRel ) {
$srcPathsRel = $src->getFileList( [
'dir' => $src->getRootStoragePath() . "/$backendRel" ] );
if ( $srcPathsRel === null ) {
$this->fatalError( "Could not list files in source container." );
}
$dstPathsRel = $dst->getFileList( [
'dir' => $dst->getRootStoragePath() . "/$backendRel" ] );
if ( $dstPathsRel === null ) {
$this->fatalError( "Could not list files in destination container." );
}
// Get the list of destination files
$relFilesDstSha1 = [];
foreach ( $dstPathsRel as $dstPathRel ) {
$relFilesDstSha1[sha1( $dstPathRel )] = 1;
}
unset( $dstPathsRel ); // free
// Get the list of missing files
$missingPathsRel = [];
foreach ( $srcPathsRel as $srcPathRel ) {
if ( !isset( $relFilesDstSha1[sha1( $srcPathRel )] ) ) {
$missingPathsRel[] = $srcPathRel;
}
}
unset( $srcPathsRel ); // free
return $missingPathsRel;
}
/**
* @param string[] $srcPathsRel
* @param string $backendRel
* @param FileBackend $src
* @param FileBackend $dst
* @return void
*/
protected function copyFileBatch(
array $srcPathsRel, $backendRel, FileBackend $src, FileBackend $dst
) {
$ops = [];
$fsFiles = [];
$copiedRel = []; // for output message
$domainId = $src->getDomainId();
// Download the batch of source files into backend cache...
if ( $this->hasOption( 'missingonly' ) ) {
$srcPaths = [];
foreach ( $srcPathsRel as $srcPathRel ) {
$srcPaths[] = $src->getRootStoragePath() . "/$backendRel/$srcPathRel";
}
$t_start = microtime( true );
$fsFiles = $src->getLocalReferenceMulti( [ 'srcs' => $srcPaths, 'latest' => 1 ] );
$elapsed_ms = floor( ( microtime( true ) - $t_start ) * 1000 );
$this->output( "\n\tDownloaded these file(s) [{$elapsed_ms}ms]:\n\t" .
implode( "\n\t", $srcPaths ) . "\n\n" );
}
// Determine what files need to be copied over...
foreach ( $srcPathsRel as $srcPathRel ) {
$srcPath = $src->getRootStoragePath() . "/$backendRel/$srcPathRel";
$dstPath = $dst->getRootStoragePath() . "/$backendRel/$srcPathRel";
if ( $this->hasOption( 'utf8only' ) && !mb_check_encoding( $srcPath, 'UTF-8' ) ) {
$this->error( "$domainId: Detected illegal (non-UTF8) path for $srcPath." );
continue;
} elseif ( !$this->hasOption( 'missingonly' )
&& $this->filesAreSame( $src, $dst, $srcPath, $dstPath )
) {
$this->output( "\tAlready have $srcPathRel.\n" );
continue; // assume already copied...
}
$fsFile = array_key_exists( $srcPath, $fsFiles )
? $fsFiles[$srcPath]
: $src->getLocalReference( [ 'src' => $srcPath, 'latest' => 1 ] );
if ( !$fsFile ) {
$src->clearCache( [ $srcPath ] );
if ( $src->fileExists( [ 'src' => $srcPath, 'latest' => 1 ] ) === false ) {
$this->error( "$domainId: File '$srcPath' was listed but does not exist." );
} else {
$this->error( "$domainId: Could not get local copy of $srcPath." );
}
continue;
} elseif ( !$fsFile->exists() ) {
// FSFileBackends just return the path for getLocalReference() and paths with
// illegal slashes may get normalized to a different path. This can cause the
// local reference to not exist...skip these broken files.
$this->error( "$domainId: Detected possible illegal path for $srcPath." );
continue;
}
$fsFiles[] = $fsFile; // keep TempFSFile objects alive as needed
// Note: prepare() is usually fast for key/value backends
$status = $dst->prepare( [ 'dir' => dirname( $dstPath ), 'bypassReadOnly' => true ] );
if ( !$status->isOK() ) {
$this->error( Status::wrap( $status )->getMessage( false, false, 'en' )->text() );
$this->fatalError( "$domainId: Could not copy $srcPath to $dstPath." );
}
$ops[] = [ 'op' => 'store',
'src' => $fsFile->getPath(), 'dst' => $dstPath, 'overwrite' => true ];
$copiedRel[] = $srcPathRel;
}
// Copy in the batch of source files...
$t_start = microtime( true );
$status = $dst->doQuickOperations( $ops, [ 'bypassReadOnly' => true ] );
if ( !$status->isOK() ) {
sleep( 10 ); // wait and retry copy again
$status = $dst->doQuickOperations( $ops, [ 'bypassReadOnly' => true ] );
}
$elapsed_ms = floor( ( microtime( true ) - $t_start ) * 1000 );
if ( !$status->isOK() ) {
$this->error( Status::wrap( $status )->getMessage( false, false, 'en' )->text() );
$this->fatalError( "$domainId: Could not copy file batch." );
} elseif ( count( $copiedRel ) ) {
$this->output( "\n\tCopied these file(s) [{$elapsed_ms}ms]:\n\t" .
implode( "\n\t", $copiedRel ) . "\n\n" );
}
}
/**
* @param string[] $dstPathsRel
* @param string $backendRel
* @param FileBackend $dst
* @return void
*/
protected function delFileBatch(
array $dstPathsRel, $backendRel, FileBackend $dst
) {
$ops = [];
$deletedRel = []; // for output message
$domainId = $dst->getDomainId();
// Determine what files need to be copied over...
foreach ( $dstPathsRel as $dstPathRel ) {
$dstPath = $dst->getRootStoragePath() . "/$backendRel/$dstPathRel";
$ops[] = [ 'op' => 'delete', 'src' => $dstPath ];
$deletedRel[] = $dstPathRel;
}
// Delete the batch of source files...
$t_start = microtime( true );
$status = $dst->doQuickOperations( $ops, [ 'bypassReadOnly' => true ] );
if ( !$status->isOK() ) {
sleep( 10 ); // wait and retry copy again
$status = $dst->doQuickOperations( $ops, [ 'bypassReadOnly' => true ] );
}
$elapsed_ms = floor( ( microtime( true ) - $t_start ) * 1000 );
if ( !$status->isOK() ) {
$this->error( Status::wrap( $status )->getMessage( false, false, 'en' )->text() );
$this->fatalError( "$domainId: Could not delete file batch." );
} elseif ( count( $deletedRel ) ) {
$this->output( "\n\tDeleted these file(s) [{$elapsed_ms}ms]:\n\t" .
implode( "\n\t", $deletedRel ) . "\n\n" );
}
}
/**
* @param FileBackend $src
* @param FileBackend $dst
* @param string $sPath
* @param string $dPath
* @return bool
*/
protected function filesAreSame( FileBackend $src, FileBackend $dst, $sPath, $dPath ) {
$skipHash = $this->hasOption( 'skiphash' );
$srcStat = $src->getFileStat( [ 'src' => $sPath ] );
$dPathSha1 = sha1( $dPath );
if ( $this->statCache !== null ) {
// All dst files are already in stat cache
$dstStat = $this->statCache[$dPathSha1] ?? false;
} else {
$dstStat = $dst->getFileStat( [ 'src' => $dPath ] );
}
// Initial fast checks to see if files are obviously different
$sameFast = (
is_array( $srcStat )
&& is_array( $dstStat ) // dest exists
&& $srcStat['size'] === $dstStat['size']
);
// More thorough checks against files
if ( !$sameFast ) {
$same = false; // no need to look farther
} elseif ( isset( $srcStat['md5'] ) && isset( $dstStat['md5'] ) ) {
// If MD5 was already in the stat info, just use it.
// This is useful as many objects stores can return this in object listing,
// so we can use it to avoid slow per-file HEADs.
$same = ( $srcStat['md5'] === $dstStat['md5'] );
} elseif ( $skipHash ) {
// This mode is good for copying to a backup location or resyncing clone
// backends in FileBackendMultiWrite (since they get writes second, they have
// higher timestamps). However, when copying the other way, this hits loads of
// false positives (possibly 100%) and wastes a bunch of time on GETs/PUTs.
// @phan-suppress-next-line PhanTypeArraySuspiciousNullable
$same = ( $srcStat['mtime'] <= $dstStat['mtime'] );
} else {
// This is the slowest method which does many per-file HEADs (unless an object
// store tracks SHA-1 in listings).
$same = ( $src->getFileSha1Base36( [ 'src' => $sPath, 'latest' => 1 ] )
=== $dst->getFileSha1Base36( [ 'src' => $dPath, 'latest' => 1 ] ) );
}
return $same;
}
}
$maintClass = CopyFileBackend::class;
require_once RUN_MAINTENANCE_IF_MAIN;