Mercurial > hg > isophonics-drupal-site
diff vendor/doctrine/cache/lib/Doctrine/Common/Cache/RiakCache.php @ 0:4c8ae668cc8c
Initial import (non-working)
author | Chris Cannam |
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date | Wed, 29 Nov 2017 16:09:58 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/vendor/doctrine/cache/lib/Doctrine/Common/Cache/RiakCache.php Wed Nov 29 16:09:58 2017 +0000 @@ -0,0 +1,250 @@ +<?php +/* + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This software consists of voluntary contributions made by many individuals + * and is licensed under the MIT license. For more information, see + * <http://www.doctrine-project.org>. + */ + +namespace Doctrine\Common\Cache; + +use Riak\Bucket; +use Riak\Connection; +use Riak\Input; +use Riak\Exception; +use Riak\Object; + +/** + * Riak cache provider. + * + * @link www.doctrine-project.org + * @since 1.1 + * @author Guilherme Blanco <guilhermeblanco@hotmail.com> + */ +class RiakCache extends CacheProvider +{ + const EXPIRES_HEADER = 'X-Riak-Meta-Expires'; + + /** + * @var \Riak\Bucket + */ + private $bucket; + + /** + * Sets the riak bucket instance to use. + * + * @param \Riak\Bucket $bucket + */ + public function __construct(Bucket $bucket) + { + $this->bucket = $bucket; + } + + /** + * {@inheritdoc} + */ + protected function doFetch($id) + { + try { + $response = $this->bucket->get($id); + + // No objects found + if ( ! $response->hasObject()) { + return false; + } + + // Check for attempted siblings + $object = ($response->hasSiblings()) + ? $this->resolveConflict($id, $response->getVClock(), $response->getObjectList()) + : $response->getFirstObject(); + + // Check for expired object + if ($this->isExpired($object)) { + $this->bucket->delete($object); + + return false; + } + + return unserialize($object->getContent()); + } catch (Exception\RiakException $e) { + // Covers: + // - Riak\ConnectionException + // - Riak\CommunicationException + // - Riak\UnexpectedResponseException + // - Riak\NotFoundException + } + + return false; + } + + /** + * {@inheritdoc} + */ + protected function doContains($id) + { + try { + // We only need the HEAD, not the entire object + $input = new Input\GetInput(); + + $input->setReturnHead(true); + + $response = $this->bucket->get($id, $input); + + // No objects found + if ( ! $response->hasObject()) { + return false; + } + + $object = $response->getFirstObject(); + + // Check for expired object + if ($this->isExpired($object)) { + $this->bucket->delete($object); + + return false; + } + + return true; + } catch (Exception\RiakException $e) { + // Do nothing + } + + return false; + } + + /** + * {@inheritdoc} + */ + protected function doSave($id, $data, $lifeTime = 0) + { + try { + $object = new Object($id); + + $object->setContent(serialize($data)); + + if ($lifeTime > 0) { + $object->addMetadata(self::EXPIRES_HEADER, (string) (time() + $lifeTime)); + } + + $this->bucket->put($object); + + return true; + } catch (Exception\RiakException $e) { + // Do nothing + } + + return false; + } + + /** + * {@inheritdoc} + */ + protected function doDelete($id) + { + try { + $this->bucket->delete($id); + + return true; + } catch (Exception\BadArgumentsException $e) { + // Key did not exist on cluster already + } catch (Exception\RiakException $e) { + // Covers: + // - Riak\Exception\ConnectionException + // - Riak\Exception\CommunicationException + // - Riak\Exception\UnexpectedResponseException + } + + return false; + } + + /** + * {@inheritdoc} + */ + protected function doFlush() + { + try { + $keyList = $this->bucket->getKeyList(); + + foreach ($keyList as $key) { + $this->bucket->delete($key); + } + + return true; + } catch (Exception\RiakException $e) { + // Do nothing + } + + return false; + } + + /** + * {@inheritdoc} + */ + protected function doGetStats() + { + // Only exposed through HTTP stats API, not Protocol Buffers API + return null; + } + + /** + * Check if a given Riak Object have expired. + * + * @param \Riak\Object $object + * + * @return bool + */ + private function isExpired(Object $object) + { + $metadataMap = $object->getMetadataMap(); + + return isset($metadataMap[self::EXPIRES_HEADER]) + && $metadataMap[self::EXPIRES_HEADER] < time(); + } + + /** + * On-read conflict resolution. Applied approach here is last write wins. + * Specific needs may override this method to apply alternate conflict resolutions. + * + * {@internal Riak does not attempt to resolve a write conflict, and store + * it as sibling of conflicted one. By following this approach, it is up to + * the next read to resolve the conflict. When this happens, your fetched + * object will have a list of siblings (read as a list of objects). + * In our specific case, we do not care about the intermediate ones since + * they are all the same read from storage, and we do apply a last sibling + * (last write) wins logic. + * If by any means our resolution generates another conflict, it'll up to + * next read to properly solve it.} + * + * @param string $id + * @param string $vClock + * @param array $objectList + * + * @return \Riak\Object + */ + protected function resolveConflict($id, $vClock, array $objectList) + { + // Our approach here is last-write wins + $winner = $objectList[count($objectList)]; + + $putInput = new Input\PutInput(); + $putInput->setVClock($vClock); + + $mergedObject = new Object($id); + $mergedObject->setContent($winner->getContent()); + + $this->bucket->put($mergedObject, $putInput); + + return $mergedObject; + } +}