CachedReader.php

<?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\Annotations;

use Doctrine\Common\Cache\Cache;

/**
 * A cache aware annotation reader.
 *
 * @author Johannes M. Schmitt <schmittjoh@gmail.com>
 * @author Benjamin Eberlei <kontakt@beberlei.de>
 */
final class CachedReader implements Reader {

  /**
   * @var string
   */
  private static $CACHE_SALT = '@[Annot]';

  /**
   * @var Reader
   */
  private $delegate;

  /**
   * @var Cache
   */
  private $cache;

  /**
   * @var boolean
   */
  private $debug;

  /**
   * @var array
   */
  private $loadedAnnotations;

  /**
   * Constructor
   *
   * @param Reader $reader
   * @param Cache $cache
   * @param bool $debug
   */
  public function __construct(Reader $reader, Cache $cache, $debug = false) {
    $this->delegate = $reader;
    $this->cache = $cache;
    $this->debug = (bool) $debug;
  }

  /**
   * Get annotations for class
   *
   * @param \ReflectionClass $class
   * @return array
   */
  public function getClassAnnotations(\ReflectionClass $class) {
    $cacheKey = $class
      ->getName();
    if (isset($this->loadedAnnotations[$cacheKey])) {
      return $this->loadedAnnotations[$cacheKey];
    }
    if (false === ($annots = $this
      ->fetchFromCache($cacheKey, $class))) {
      $annots = $this->delegate
        ->getClassAnnotations($class);
      $this
        ->saveToCache($cacheKey, $annots);
    }
    return $this->loadedAnnotations[$cacheKey] = $annots;
  }

  /**
   * Get selected annotation for class
   *
   * @param \ReflectionClass $class
   * @param string $annotationName
   * @return null
   */
  public function getClassAnnotation(\ReflectionClass $class, $annotationName) {
    foreach ($this
      ->getClassAnnotations($class) as $annot) {
      if ($annot instanceof $annotationName) {
        return $annot;
      }
    }
    return null;
  }

  /**
   * Get annotations for property
   *
   * @param \ReflectionProperty $property
   * @return array
   */
  public function getPropertyAnnotations(\ReflectionProperty $property) {
    $class = $property
      ->getDeclaringClass();
    $cacheKey = $class
      ->getName() . '$' . $property
      ->getName();
    if (isset($this->loadedAnnotations[$cacheKey])) {
      return $this->loadedAnnotations[$cacheKey];
    }
    if (false === ($annots = $this
      ->fetchFromCache($cacheKey, $class))) {
      $annots = $this->delegate
        ->getPropertyAnnotations($property);
      $this
        ->saveToCache($cacheKey, $annots);
    }
    return $this->loadedAnnotations[$cacheKey] = $annots;
  }

  /**
   * Get selected annotation for property
   *
   * @param \ReflectionProperty $property
   * @param string $annotationName
   * @return null
   */
  public function getPropertyAnnotation(\ReflectionProperty $property, $annotationName) {
    foreach ($this
      ->getPropertyAnnotations($property) as $annot) {
      if ($annot instanceof $annotationName) {
        return $annot;
      }
    }
    return null;
  }

  /**
   * Get method annotations
   *
   * @param \ReflectionMethod $method
   * @return array
   */
  public function getMethodAnnotations(\ReflectionMethod $method) {
    $class = $method
      ->getDeclaringClass();
    $cacheKey = $class
      ->getName() . '#' . $method
      ->getName();
    if (isset($this->loadedAnnotations[$cacheKey])) {
      return $this->loadedAnnotations[$cacheKey];
    }
    if (false === ($annots = $this
      ->fetchFromCache($cacheKey, $class))) {
      $annots = $this->delegate
        ->getMethodAnnotations($method);
      $this
        ->saveToCache($cacheKey, $annots);
    }
    return $this->loadedAnnotations[$cacheKey] = $annots;
  }

  /**
   * Get selected method annotation
   *
   * @param \ReflectionMethod $method
   * @param string $annotationName
   * @return null
   */
  public function getMethodAnnotation(\ReflectionMethod $method, $annotationName) {
    foreach ($this
      ->getMethodAnnotations($method) as $annot) {
      if ($annot instanceof $annotationName) {
        return $annot;
      }
    }
    return null;
  }

  /**
   * Clear loaded annotations
   */
  public function clearLoadedAnnotations() {
    $this->loadedAnnotations = array();
  }

  /**
   * Fetches a value from the cache.
   *
   * @param string           $rawCacheKey The cache key.
   * @param \ReflectionClass $class       The related class.
   * @return mixed|boolean The cached value or false when the value is not in cache.
   */
  private function fetchFromCache($rawCacheKey, \ReflectionClass $class) {
    $cacheKey = $rawCacheKey . self::$CACHE_SALT;
    if (($data = $this->cache
      ->fetch($cacheKey)) !== false) {
      if (!$this->debug || $this
        ->isCacheFresh($cacheKey, $class)) {
        return $data;
      }
    }
    return false;
  }

  /**
   * Saves a value to the cache
   *
   * @param string $rawCacheKey The cache key.
   * @param mixed  $value       The value.
   */
  private function saveToCache($rawCacheKey, $value) {
    $cacheKey = $rawCacheKey . self::$CACHE_SALT;
    $this->cache
      ->save($cacheKey, $value);
    if ($this->debug) {
      $this->cache
        ->save('[C]' . $cacheKey, time());
    }
  }

  /**
   * Check if cache is fresh
   *
   * @param string $cacheKey
   * @param \ReflectionClass $class
   * @return bool
   */
  private function isCacheFresh($cacheKey, \ReflectionClass $class) {
    if (false === ($filename = $class
      ->getFilename())) {
      return true;
    }
    return $this->cache
      ->fetch('[C]' . $cacheKey) >= filemtime($filename);
  }

}