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See Release Notes

  • Bug fixes for general core bugs in 3.10.x will end 8 November 2021 (12 months).
  • Bug fixes for security issues in 3.10.x will end 9 May 2022 (18 months).
  • PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.
<?php
/*
 * Copyright 2016-2017 MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

namespace MongoDB\GridFS;

> use ArrayIterator;
use MongoDB\Collection; use MongoDB\Driver\Cursor; use MongoDB\Driver\Manager; use MongoDB\Driver\ReadPreference; use MongoDB\Exception\InvalidArgumentException; use MongoDB\UpdateResult;
> use MultipleIterator;
use stdClass; use function abs;
> use function count; use function sprintf; > use function is_numeric;
/** * CollectionWrapper abstracts the GridFS files and chunks collections. * * @internal */ class CollectionWrapper { /** @var string */ private $bucketName; /** @var Collection */ private $chunksCollection; /** @var string */ private $databaseName; /** @var boolean */ private $checkedIndexes = false; /** @var Collection */ private $filesCollection; /** * Constructs a GridFS collection wrapper. * * @see Collection::__construct() for supported options * @param Manager $manager Manager instance from the driver * @param string $databaseName Database name * @param string $bucketName Bucket name * @param array $collectionOptions Collection options * @throws InvalidArgumentException */ public function __construct(Manager $manager, $databaseName, $bucketName, array $collectionOptions = []) { $this->databaseName = (string) $databaseName; $this->bucketName = (string) $bucketName; $this->filesCollection = new Collection($manager, $databaseName, sprintf('%s.files', $bucketName), $collectionOptions); $this->chunksCollection = new Collection($manager, $databaseName, sprintf('%s.chunks', $bucketName), $collectionOptions); } /** * Deletes all GridFS chunks for a given file ID. * * @param mixed $id */ public function deleteChunksByFilesId($id) { $this->chunksCollection->deleteMany(['files_id' => $id]); } /** * Deletes a GridFS file and related chunks by ID. * * @param mixed $id */ public function deleteFileAndChunksById($id) { $this->filesCollection->deleteOne(['_id' => $id]); $this->chunksCollection->deleteMany(['files_id' => $id]); } /** * Drops the GridFS files and chunks collections. */ public function dropCollections() { $this->filesCollection->drop(['typeMap' => []]); $this->chunksCollection->drop(['typeMap' => []]); } /** * Finds GridFS chunk documents for a given file ID and optional offset. * * @param mixed $id File ID * @param integer $fromChunk Starting chunk (inclusive) * @return Cursor */ public function findChunksByFileId($id, $fromChunk = 0) { return $this->chunksCollection->find( [ 'files_id' => $id, 'n' => ['$gte' => $fromChunk], ], [ 'sort' => ['n' => 1], 'typeMap' => ['root' => 'stdClass'], ] ); } /** * Finds a GridFS file document for a given filename and revision. * * Revision numbers are defined as follows: * * * 0 = the original stored file * * 1 = the first revision * * 2 = the second revision * * etc… * * -2 = the second most recent revision * * -1 = the most recent revision * * @see Bucket::downloadToStreamByName() * @see Bucket::openDownloadStreamByName() * @param string $filename * @param integer $revision * @return stdClass|null */ public function findFileByFilenameAndRevision($filename, $revision) { $filename = (string) $filename; $revision = (integer) $revision; if ($revision < 0) { $skip = abs($revision) - 1; $sortOrder = -1; } else { $skip = $revision; $sortOrder = 1; } return $this->filesCollection->findOne( ['filename' => $filename], [ 'skip' => $skip, 'sort' => ['uploadDate' => $sortOrder], 'typeMap' => ['root' => 'stdClass'], ] ); } /** * Finds a GridFS file document for a given ID. * * @param mixed $id * @return stdClass|null */ public function findFileById($id) { return $this->filesCollection->findOne( ['_id' => $id], ['typeMap' => ['root' => 'stdClass']] ); } /** * Finds documents from the GridFS bucket's files collection. * * @see Find::__construct() for supported options * @param array|object $filter Query by which to filter documents * @param array $options Additional options * @return Cursor */ public function findFiles($filter, array $options = []) { return $this->filesCollection->find($filter, $options); } /** * Finds a single document from the GridFS bucket's files collection. * * @param array|object $filter Query by which to filter documents * @param array $options Additional options * @return array|object|null */ public function findOneFile($filter, array $options = []) { return $this->filesCollection->findOne($filter, $options); } /** * Return the bucket name. * * @return string */ public function getBucketName() { return $this->bucketName; } /** * Return the chunks collection. * * @return Collection */ public function getChunksCollection() { return $this->chunksCollection; } /** * Return the database name. * * @return string */ public function getDatabaseName() { return $this->databaseName; } /** * Return the files collection. * * @return Collection */ public function getFilesCollection() { return $this->filesCollection; } /** * Inserts a document into the chunks collection. * * @param array|object $chunk Chunk document */ public function insertChunk($chunk) { if (! $this->checkedIndexes) { $this->ensureIndexes(); } $this->chunksCollection->insertOne($chunk); } /** * Inserts a document into the files collection. * * The file document should be inserted after all chunks have been inserted. * * @param array|object $file File document */ public function insertFile($file) { if (! $this->checkedIndexes) { $this->ensureIndexes(); } $this->filesCollection->insertOne($file); } /** * Updates the filename field in the file document for a given ID. * * @param mixed $id * @param string $filename * @return UpdateResult */ public function updateFilenameForId($id, $filename) { return $this->filesCollection->updateOne( ['_id' => $id], ['$set' => ['filename' => (string) $filename]] ); } /** * Create an index on the chunks collection if it does not already exist. */ private function ensureChunksIndex() {
> $expectedIndex = ['files_id' => 1, 'n' => 1]; foreach ($this->chunksCollection->listIndexes() as $index) { >
< if ($index->isUnique() && $index->getKey() === ['files_id' => 1, 'n' => 1]) {
> if ($index->isUnique() && $this->indexKeysMatch($expectedIndex, $index->getKey())) {
return; } }
< $this->chunksCollection->createIndex(['files_id' => 1, 'n' => 1], ['unique' => true]);
> $this->chunksCollection->createIndex($expectedIndex, ['unique' => true]);
} /** * Create an index on the files collection if it does not already exist. */ private function ensureFilesIndex() {
> $expectedIndex = ['filename' => 1, 'uploadDate' => 1]; foreach ($this->filesCollection->listIndexes() as $index) { >
< if ($index->getKey() === ['filename' => 1, 'uploadDate' => 1]) {
> if ($this->indexKeysMatch($expectedIndex, $index->getKey())) {
return; } }
< $this->filesCollection->createIndex(['filename' => 1, 'uploadDate' => 1]);
> $this->filesCollection->createIndex($expectedIndex);
} /** * Ensure indexes on the files and chunks collections exist. * * This method is called once before the first write operation on a GridFS * bucket. Indexes are only be created if the files collection is empty. */ private function ensureIndexes() { if ($this->checkedIndexes) { return; } $this->checkedIndexes = true; if (! $this->isFilesCollectionEmpty()) { return; } $this->ensureFilesIndex(); $this->ensureChunksIndex();
> } } > > private function indexKeysMatch(array $expectedKeys, array $actualKeys) : bool /** > { * Returns whether the files collection is empty. > if (count($expectedKeys) !== count($actualKeys)) { * > return false; * @return boolean > } */ > private function isFilesCollectionEmpty() > $iterator = new MultipleIterator(MultipleIterator::MIT_NEED_ANY); { > $iterator->attachIterator(new ArrayIterator($expectedKeys)); return null === $this->filesCollection->findOne([], [ > $iterator->attachIterator(new ArrayIterator($actualKeys)); 'readPreference' => new ReadPreference(ReadPreference::RP_PRIMARY), > 'projection' => ['_id' => 1], > foreach ($iterator as $key => $value) { 'typeMap' => [], > list($expectedKey, $actualKey) = $key; ]); > list($expectedValue, $actualValue) = $value; } > } > if ($expectedKey !== $actualKey) { > return false; > } > > /* Since we don't expect special indexes (e.g. text), we mark any > * index with a non-numeric definition as unequal. All others are > * compared against their int value to avoid differences due to > * some drivers using float values in the key specification. */ > if (! is_numeric($actualValue) || (int) $expectedValue !== (int) $actualValue) { > return false; > } > } > > return true;