diff options
Diffstat (limited to 'vendor/guzzle/guzzle/src/Guzzle/Plugin/Cache/CachePlugin.php')
| -rw-r--r-- | vendor/guzzle/guzzle/src/Guzzle/Plugin/Cache/CachePlugin.php | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/vendor/guzzle/guzzle/src/Guzzle/Plugin/Cache/CachePlugin.php b/vendor/guzzle/guzzle/src/Guzzle/Plugin/Cache/CachePlugin.php new file mode 100644 index 0000000..ce4b317 --- /dev/null +++ b/vendor/guzzle/guzzle/src/Guzzle/Plugin/Cache/CachePlugin.php @@ -0,0 +1,353 @@ +<?php + +namespace Guzzle\Plugin\Cache; + +use Guzzle\Cache\CacheAdapterFactory; +use Guzzle\Cache\CacheAdapterInterface; +use Guzzle\Common\Event; +use Guzzle\Common\Exception\InvalidArgumentException; +use Guzzle\Common\Version; +use Guzzle\Http\Message\RequestInterface; +use Guzzle\Http\Message\Response; +use Guzzle\Cache\DoctrineCacheAdapter; +use Guzzle\Http\Exception\CurlException; +use Doctrine\Common\Cache\ArrayCache; +use Symfony\Component\EventDispatcher\EventSubscriberInterface; + +/** + * Plugin to enable the caching of GET and HEAD requests. Caching can be done on all requests passing through this + * plugin or only after retrieving resources with cacheable response headers. + * + * This is a simple implementation of RFC 2616 and should be considered a private transparent proxy cache, meaning + * authorization and private data can be cached. + * + * It also implements RFC 5861's `stale-if-error` Cache-Control extension, allowing stale cache responses to be used + * when an error is encountered (such as a `500 Internal Server Error` or DNS failure). + */ +class CachePlugin implements EventSubscriberInterface +{ + /** @var RevalidationInterface Cache revalidation strategy */ + protected $revalidation; + + /** @var CanCacheStrategyInterface Object used to determine if a request can be cached */ + protected $canCache; + + /** @var CacheStorageInterface $cache Object used to cache responses */ + protected $storage; + + /** @var bool */ + protected $autoPurge; + + /** + * @param array|CacheAdapterInterface|CacheStorageInterface $options Array of options for the cache plugin, + * cache adapter, or cache storage object. + * - CacheStorageInterface storage: Adapter used to cache responses + * - RevalidationInterface revalidation: Cache revalidation strategy + * - CanCacheInterface can_cache: Object used to determine if a request can be cached + * - bool auto_purge Set to true to automatically PURGE resources when non-idempotent + * requests are sent to a resource. Defaults to false. + * @throws InvalidArgumentException if no cache is provided and Doctrine cache is not installed + */ + public function __construct($options = null) + { + if (!is_array($options)) { + if ($options instanceof CacheAdapterInterface) { + $options = array('storage' => new DefaultCacheStorage($options)); + } elseif ($options instanceof CacheStorageInterface) { + $options = array('storage' => $options); + } elseif ($options) { + $options = array('storage' => new DefaultCacheStorage(CacheAdapterFactory::fromCache($options))); + } elseif (!class_exists('Doctrine\Common\Cache\ArrayCache')) { + // @codeCoverageIgnoreStart + throw new InvalidArgumentException('No cache was provided and Doctrine is not installed'); + // @codeCoverageIgnoreEnd + } + } + + $this->autoPurge = isset($options['auto_purge']) ? $options['auto_purge'] : false; + + // Add a cache storage if a cache adapter was provided + $this->storage = isset($options['storage']) + ? $options['storage'] + : new DefaultCacheStorage(new DoctrineCacheAdapter(new ArrayCache())); + + if (!isset($options['can_cache'])) { + $this->canCache = new DefaultCanCacheStrategy(); + } else { + $this->canCache = is_callable($options['can_cache']) + ? new CallbackCanCacheStrategy($options['can_cache']) + : $options['can_cache']; + } + + // Use the provided revalidation strategy or the default + $this->revalidation = isset($options['revalidation']) + ? $options['revalidation'] + : new DefaultRevalidation($this->storage, $this->canCache); + } + + public static function getSubscribedEvents() + { + return array( + 'request.before_send' => array('onRequestBeforeSend', -255), + 'request.sent' => array('onRequestSent', 255), + 'request.error' => array('onRequestError', 0), + 'request.exception' => array('onRequestException', 0), + ); + } + + /** + * Check if a response in cache will satisfy the request before sending + * + * @param Event $event + */ + public function onRequestBeforeSend(Event $event) + { + $request = $event['request']; + $request->addHeader('Via', sprintf('%s GuzzleCache/%s', $request->getProtocolVersion(), Version::VERSION)); + + if (!$this->canCache->canCacheRequest($request)) { + switch ($request->getMethod()) { + case 'PURGE': + $this->purge($request); + $request->setResponse(new Response(200, array(), 'purged')); + break; + case 'PUT': + case 'POST': + case 'DELETE': + case 'PATCH': + if ($this->autoPurge) { + $this->purge($request); + } + } + return; + } + + if ($response = $this->storage->fetch($request)) { + $params = $request->getParams(); + $params['cache.lookup'] = true; + $response->setHeader( + 'Age', + time() - strtotime($response->getDate() ? : $response->getLastModified() ?: 'now') + ); + // Validate that the response satisfies the request + if ($this->canResponseSatisfyRequest($request, $response)) { + if (!isset($params['cache.hit'])) { + $params['cache.hit'] = true; + } + $request->setResponse($response); + } + } + } + + /** + * If possible, store a response in cache after sending + * + * @param Event $event + */ + public function onRequestSent(Event $event) + { + $request = $event['request']; + $response = $event['response']; + + if ($request->getParams()->get('cache.hit') === null && + $this->canCache->canCacheRequest($request) && + $this->canCache->canCacheResponse($response) + ) { + $this->storage->cache($request, $response); + } + + $this->addResponseHeaders($request, $response); + } + + /** + * If possible, return a cache response on an error + * + * @param Event $event + */ + public function onRequestError(Event $event) + { + $request = $event['request']; + + if (!$this->canCache->canCacheRequest($request)) { + return; + } + + if ($response = $this->storage->fetch($request)) { + $response->setHeader( + 'Age', + time() - strtotime($response->getLastModified() ? : $response->getDate() ?: 'now') + ); + + if ($this->canResponseSatisfyFailedRequest($request, $response)) { + $request->getParams()->set('cache.hit', 'error'); + $this->addResponseHeaders($request, $response); + $event['response'] = $response; + $event->stopPropagation(); + } + } + } + + /** + * If possible, set a cache response on a cURL exception + * + * @param Event $event + * + * @return null + */ + public function onRequestException(Event $event) + { + if (!$event['exception'] instanceof CurlException) { + return; + } + + $request = $event['request']; + if (!$this->canCache->canCacheRequest($request)) { + return; + } + + if ($response = $this->storage->fetch($request)) { + $response->setHeader('Age', time() - strtotime($response->getDate() ? : 'now')); + if (!$this->canResponseSatisfyFailedRequest($request, $response)) { + return; + } + $request->getParams()->set('cache.hit', 'error'); + $request->setResponse($response); + $this->addResponseHeaders($request, $response); + $event->stopPropagation(); + } + } + + /** + * Check if a cache response satisfies a request's caching constraints + * + * @param RequestInterface $request Request to validate + * @param Response $response Response to validate + * + * @return bool + */ + public function canResponseSatisfyRequest(RequestInterface $request, Response $response) + { + $responseAge = $response->calculateAge(); + $reqc = $request->getHeader('Cache-Control'); + $resc = $response->getHeader('Cache-Control'); + + // Check the request's max-age header against the age of the response + if ($reqc && $reqc->hasDirective('max-age') && + $responseAge > $reqc->getDirective('max-age')) { + return false; + } + + // Check the response's max-age header + if ($response->isFresh() === false) { + $maxStale = $reqc ? $reqc->getDirective('max-stale') : null; + if (null !== $maxStale) { + if ($maxStale !== true && $response->getFreshness() < (-1 * $maxStale)) { + return false; + } + } elseif ($resc && $resc->hasDirective('max-age') + && $responseAge > $resc->getDirective('max-age') + ) { + return false; + } + } + + if ($this->revalidation->shouldRevalidate($request, $response)) { + try { + return $this->revalidation->revalidate($request, $response); + } catch (CurlException $e) { + $request->getParams()->set('cache.hit', 'error'); + return $this->canResponseSatisfyFailedRequest($request, $response); + } + } + + return true; + } + + /** + * Check if a cache response satisfies a failed request's caching constraints + * + * @param RequestInterface $request Request to validate + * @param Response $response Response to validate + * + * @return bool + */ + public function canResponseSatisfyFailedRequest(RequestInterface $request, Response $response) + { + $reqc = $request->getHeader('Cache-Control'); + $resc = $response->getHeader('Cache-Control'); + $requestStaleIfError = $reqc ? $reqc->getDirective('stale-if-error') : null; + $responseStaleIfError = $resc ? $resc->getDirective('stale-if-error') : null; + + if (!$requestStaleIfError && !$responseStaleIfError) { + return false; + } + + if (is_numeric($requestStaleIfError) && $response->getAge() - $response->getMaxAge() > $requestStaleIfError) { + return false; + } + + if (is_numeric($responseStaleIfError) && $response->getAge() - $response->getMaxAge() > $responseStaleIfError) { + return false; + } + + return true; + } + + /** + * Purge all cache entries for a given URL + * + * @param string $url URL to purge + */ + public function purge($url) + { + // BC compatibility with previous version that accepted a Request object + $url = $url instanceof RequestInterface ? $url->getUrl() : $url; + $this->storage->purge($url); + } + + /** + * Add the plugin's headers to a response + * + * @param RequestInterface $request Request + * @param Response $response Response to add headers to + */ + protected function addResponseHeaders(RequestInterface $request, Response $response) + { + $params = $request->getParams(); + $response->setHeader('Via', sprintf('%s GuzzleCache/%s', $request->getProtocolVersion(), Version::VERSION)); + + $lookup = ($params['cache.lookup'] === true ? 'HIT' : 'MISS') . ' from GuzzleCache'; + if ($header = $response->getHeader('X-Cache-Lookup')) { + // Don't add duplicates + $values = $header->toArray(); + $values[] = $lookup; + $response->setHeader('X-Cache-Lookup', array_unique($values)); + } else { + $response->setHeader('X-Cache-Lookup', $lookup); + } + + if ($params['cache.hit'] === true) { + $xcache = 'HIT from GuzzleCache'; + } elseif ($params['cache.hit'] == 'error') { + $xcache = 'HIT_ERROR from GuzzleCache'; + } else { + $xcache = 'MISS from GuzzleCache'; + } + + if ($header = $response->getHeader('X-Cache')) { + // Don't add duplicates + $values = $header->toArray(); + $values[] = $xcache; + $response->setHeader('X-Cache', array_unique($values)); + } else { + $response->setHeader('X-Cache', $xcache); + } + + if ($response->isFresh() === false) { + $response->addHeader('Warning', sprintf('110 GuzzleCache/%s "Response is stale"', Version::VERSION)); + if ($params['cache.hit'] === 'error') { + $response->addHeader('Warning', sprintf('111 GuzzleCache/%s "Revalidation failed"', Version::VERSION)); + } + } + } +} |