/home/mip/public_html/img/credit/datatables/HttpCache.tar
ResponseCacheStrategy.php 0000644 00000022072 15152054541 0011527 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Response;
/**
* ResponseCacheStrategy knows how to compute the Response cache HTTP header
* based on the different response cache headers.
*
* This implementation changes the main response TTL to the smallest TTL received
* or force validation if one of the surrogates has validation cache strategy.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class ResponseCacheStrategy implements ResponseCacheStrategyInterface
{
/**
* Cache-Control headers that are sent to the final response if they appear in ANY of the responses.
*/
private const OVERRIDE_DIRECTIVES = ['private', 'no-cache', 'no-store', 'no-transform', 'must-revalidate', 'proxy-revalidate'];
/**
* Cache-Control headers that are sent to the final response if they appear in ALL of the responses.
*/
private const INHERIT_DIRECTIVES = ['public', 'immutable'];
private int $embeddedResponses = 0;
private bool $isNotCacheableResponseEmbedded = false;
private int $age = 0;
private \DateTimeInterface|null|false $lastModified = null;
private array $flagDirectives = [
'no-cache' => null,
'no-store' => null,
'no-transform' => null,
'must-revalidate' => null,
'proxy-revalidate' => null,
'public' => null,
'private' => null,
'immutable' => null,
];
private array $ageDirectives = [
'max-age' => null,
's-maxage' => null,
'expires' => null,
];
/**
* @return void
*/
public function add(Response $response)
{
++$this->embeddedResponses;
foreach (self::OVERRIDE_DIRECTIVES as $directive) {
if ($response->headers->hasCacheControlDirective($directive)) {
$this->flagDirectives[$directive] = true;
}
}
foreach (self::INHERIT_DIRECTIVES as $directive) {
if (false !== $this->flagDirectives[$directive]) {
$this->flagDirectives[$directive] = $response->headers->hasCacheControlDirective($directive);
}
}
$age = $response->getAge();
$this->age = max($this->age, $age);
if ($this->willMakeFinalResponseUncacheable($response)) {
$this->isNotCacheableResponseEmbedded = true;
return;
}
$isHeuristicallyCacheable = $response->headers->hasCacheControlDirective('public');
$maxAge = $response->headers->hasCacheControlDirective('max-age') ? (int) $response->headers->getCacheControlDirective('max-age') : null;
$this->storeRelativeAgeDirective('max-age', $maxAge, $age, $isHeuristicallyCacheable);
$sharedMaxAge = $response->headers->hasCacheControlDirective('s-maxage') ? (int) $response->headers->getCacheControlDirective('s-maxage') : $maxAge;
$this->storeRelativeAgeDirective('s-maxage', $sharedMaxAge, $age, $isHeuristicallyCacheable);
$expires = $response->getExpires();
$expires = null !== $expires ? (int) $expires->format('U') - (int) $response->getDate()->format('U') : null;
$this->storeRelativeAgeDirective('expires', $expires >= 0 ? $expires : null, 0, $isHeuristicallyCacheable);
if (false !== $this->lastModified) {
$lastModified = $response->getLastModified();
$this->lastModified = $lastModified ? max($this->lastModified, $lastModified) : false;
}
}
/**
* @return void
*/
public function update(Response $response)
{
// if we have no embedded Response, do nothing
if (0 === $this->embeddedResponses) {
return;
}
// Remove Etag since it cannot be merged from embedded responses.
$response->setEtag(null);
$this->add($response);
$response->headers->set('Age', $this->age);
if ($this->isNotCacheableResponseEmbedded) {
$response->setLastModified(null);
if ($this->flagDirectives['no-store']) {
$response->headers->set('Cache-Control', 'no-cache, no-store, must-revalidate');
} else {
$response->headers->set('Cache-Control', 'no-cache, must-revalidate');
}
return;
}
$response->setLastModified($this->lastModified ?: null);
$flags = array_filter($this->flagDirectives);
if (isset($flags['must-revalidate'])) {
$flags['no-cache'] = true;
}
$response->headers->set('Cache-Control', implode(', ', array_keys($flags)));
$maxAge = null;
if (is_numeric($this->ageDirectives['max-age'])) {
$maxAge = $this->ageDirectives['max-age'] + $this->age;
$response->headers->addCacheControlDirective('max-age', $maxAge);
}
if (is_numeric($this->ageDirectives['s-maxage'])) {
$sMaxage = $this->ageDirectives['s-maxage'] + $this->age;
if ($maxAge !== $sMaxage) {
$response->headers->addCacheControlDirective('s-maxage', $sMaxage);
}
}
if (is_numeric($this->ageDirectives['expires'])) {
$date = clone $response->getDate();
$date = $date->modify('+'.($this->ageDirectives['expires'] + $this->age).' seconds');
$response->setExpires($date);
}
}
/**
* RFC2616, Section 13.4.
*
* @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.4
*/
private function willMakeFinalResponseUncacheable(Response $response): bool
{
// RFC2616: A response received with a status code of 200, 203, 300, 301 or 410
// MAY be stored by a cache […] unless a cache-control directive prohibits caching.
if ($response->headers->hasCacheControlDirective('no-cache')
|| $response->headers->hasCacheControlDirective('no-store')
) {
return true;
}
// Etag headers cannot be merged, they render the response uncacheable
// by default (except if the response also has max-age etc.).
if (null === $response->getEtag() && \in_array($response->getStatusCode(), [200, 203, 300, 301, 410])) {
return false;
}
// RFC2616: A response received with any other status code (e.g. status codes 302 and 307)
// MUST NOT be returned in a reply to a subsequent request unless there are
// cache-control directives or another header(s) that explicitly allow it.
$cacheControl = ['max-age', 's-maxage', 'must-revalidate', 'proxy-revalidate', 'public', 'private'];
foreach ($cacheControl as $key) {
if ($response->headers->hasCacheControlDirective($key)) {
return false;
}
}
if ($response->headers->has('Expires')) {
return false;
}
return true;
}
/**
* Store lowest max-age/s-maxage/expires for the final response.
*
* The response might have been stored in cache a while ago. To keep things comparable,
* we have to subtract the age so that the value is normalized for an age of 0.
*
* If the value is lower than the currently stored value, we update the value, to keep a rolling
* minimal value of each instruction.
*
* If the value is NULL and the isHeuristicallyCacheable parameter is false, the directive will
* not be set on the final response. In this case, not all responses had the directive set and no
* value can be found that satisfies the requirements of all responses. The directive will be dropped
* from the final response.
*
* If the isHeuristicallyCacheable parameter is true, however, the current response has been marked
* as cacheable in a public (shared) cache, but did not provide an explicit lifetime that would serve
* as an upper bound. In this case, we can proceed and possibly keep the directive on the final response.
*/
private function storeRelativeAgeDirective(string $directive, ?int $value, int $age, bool $isHeuristicallyCacheable): void
{
if (null === $value) {
if ($isHeuristicallyCacheable) {
/*
* See https://datatracker.ietf.org/doc/html/rfc7234#section-4.2.2
* This particular response does not require maximum lifetime; heuristics might be applied.
* Other responses, however, might have more stringent requirements on maximum lifetime.
* So, return early here so that the final response can have the more limiting value set.
*/
return;
}
$this->ageDirectives[$directive] = false;
}
if (false !== $this->ageDirectives[$directive]) {
$value -= $age;
$this->ageDirectives[$directive] = null !== $this->ageDirectives[$directive] ? min($this->ageDirectives[$directive], $value) : $value;
}
}
}
ResponseCacheStrategyInterface.php 0000644 00000002037 15152054541 0013347 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* This code is partially based on the Rack-Cache library by Ryan Tomayko,
* which is released under the MIT license.
* (based on commit 02d2b48d75bcb63cf1c0c7149c077ad256542801)
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Response;
/**
* ResponseCacheStrategyInterface implementations know how to compute the
* Response cache HTTP header based on the different response cache headers.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
interface ResponseCacheStrategyInterface
{
/**
* Adds a Response.
*
* @return void
*/
public function add(Response $response);
/**
* Updates the Response HTTP headers based on the embedded Responses.
*
* @return void
*/
public function update(Response $response);
}
Store.php 0000644 00000034562 15152054541 0006365 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* This code is partially based on the Rack-Cache library by Ryan Tomayko,
* which is released under the MIT license.
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
/**
* Store implements all the logic for storing cache metadata (Request and Response headers).
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class Store implements StoreInterface
{
protected $root;
/** @var \SplObjectStorage<Request, string> */
private \SplObjectStorage $keyCache;
/** @var array<string, resource> */
private array $locks = [];
private array $options;
/**
* Constructor.
*
* The available options are:
*
* * private_headers Set of response headers that should not be stored
* when a response is cached. (default: Set-Cookie)
*
* @throws \RuntimeException
*/
public function __construct(string $root, array $options = [])
{
$this->root = $root;
if (!is_dir($this->root) && !@mkdir($this->root, 0777, true) && !is_dir($this->root)) {
throw new \RuntimeException(sprintf('Unable to create the store directory (%s).', $this->root));
}
$this->keyCache = new \SplObjectStorage();
$this->options = array_merge([
'private_headers' => ['Set-Cookie'],
], $options);
}
/**
* Cleanups storage.
*
* @return void
*/
public function cleanup()
{
// unlock everything
foreach ($this->locks as $lock) {
flock($lock, \LOCK_UN);
fclose($lock);
}
$this->locks = [];
}
/**
* Tries to lock the cache for a given Request, without blocking.
*
* @return bool|string true if the lock is acquired, the path to the current lock otherwise
*/
public function lock(Request $request): bool|string
{
$key = $this->getCacheKey($request);
if (!isset($this->locks[$key])) {
$path = $this->getPath($key);
if (!is_dir(\dirname($path)) && false === @mkdir(\dirname($path), 0777, true) && !is_dir(\dirname($path))) {
return $path;
}
$h = fopen($path, 'c');
if (!flock($h, \LOCK_EX | \LOCK_NB)) {
fclose($h);
return $path;
}
$this->locks[$key] = $h;
}
return true;
}
/**
* Releases the lock for the given Request.
*
* @return bool False if the lock file does not exist or cannot be unlocked, true otherwise
*/
public function unlock(Request $request): bool
{
$key = $this->getCacheKey($request);
if (isset($this->locks[$key])) {
flock($this->locks[$key], \LOCK_UN);
fclose($this->locks[$key]);
unset($this->locks[$key]);
return true;
}
return false;
}
public function isLocked(Request $request): bool
{
$key = $this->getCacheKey($request);
if (isset($this->locks[$key])) {
return true; // shortcut if lock held by this process
}
if (!is_file($path = $this->getPath($key))) {
return false;
}
$h = fopen($path, 'r');
flock($h, \LOCK_EX | \LOCK_NB, $wouldBlock);
flock($h, \LOCK_UN); // release the lock we just acquired
fclose($h);
return (bool) $wouldBlock;
}
/**
* Locates a cached Response for the Request provided.
*/
public function lookup(Request $request): ?Response
{
$key = $this->getCacheKey($request);
if (!$entries = $this->getMetadata($key)) {
return null;
}
// find a cached entry that matches the request.
$match = null;
foreach ($entries as $entry) {
if ($this->requestsMatch(isset($entry[1]['vary'][0]) ? implode(', ', $entry[1]['vary']) : '', $request->headers->all(), $entry[0])) {
$match = $entry;
break;
}
}
if (null === $match) {
return null;
}
$headers = $match[1];
if (file_exists($path = $this->getPath($headers['x-content-digest'][0]))) {
return $this->restoreResponse($headers, $path);
}
// TODO the metaStore referenced an entity that doesn't exist in
// the entityStore. We definitely want to return nil but we should
// also purge the entry from the meta-store when this is detected.
return null;
}
/**
* Writes a cache entry to the store for the given Request and Response.
*
* Existing entries are read and any that match the response are removed. This
* method calls write with the new list of cache entries.
*
* @throws \RuntimeException
*/
public function write(Request $request, Response $response): string
{
$key = $this->getCacheKey($request);
$storedEnv = $this->persistRequest($request);
if ($response->headers->has('X-Body-File')) {
// Assume the response came from disk, but at least perform some safeguard checks
if (!$response->headers->has('X-Content-Digest')) {
throw new \RuntimeException('A restored response must have the X-Content-Digest header.');
}
$digest = $response->headers->get('X-Content-Digest');
if ($this->getPath($digest) !== $response->headers->get('X-Body-File')) {
throw new \RuntimeException('X-Body-File and X-Content-Digest do not match.');
}
// Everything seems ok, omit writing content to disk
} else {
$digest = $this->generateContentDigest($response);
$response->headers->set('X-Content-Digest', $digest);
if (!$this->save($digest, $response->getContent(), false)) {
throw new \RuntimeException('Unable to store the entity.');
}
if (!$response->headers->has('Transfer-Encoding')) {
$response->headers->set('Content-Length', \strlen($response->getContent()));
}
}
// read existing cache entries, remove non-varying, and add this one to the list
$entries = [];
$vary = $response->headers->get('vary');
foreach ($this->getMetadata($key) as $entry) {
if (!isset($entry[1]['vary'][0])) {
$entry[1]['vary'] = [''];
}
if ($entry[1]['vary'][0] != $vary || !$this->requestsMatch($vary ?? '', $entry[0], $storedEnv)) {
$entries[] = $entry;
}
}
$headers = $this->persistResponse($response);
unset($headers['age']);
foreach ($this->options['private_headers'] as $h) {
unset($headers[strtolower($h)]);
}
array_unshift($entries, [$storedEnv, $headers]);
if (!$this->save($key, serialize($entries))) {
throw new \RuntimeException('Unable to store the metadata.');
}
return $key;
}
/**
* Returns content digest for $response.
*/
protected function generateContentDigest(Response $response): string
{
return 'en'.hash('xxh128', $response->getContent());
}
/**
* Invalidates all cache entries that match the request.
*
* @return void
*
* @throws \RuntimeException
*/
public function invalidate(Request $request)
{
$modified = false;
$key = $this->getCacheKey($request);
$entries = [];
foreach ($this->getMetadata($key) as $entry) {
$response = $this->restoreResponse($entry[1]);
if ($response->isFresh()) {
$response->expire();
$modified = true;
$entries[] = [$entry[0], $this->persistResponse($response)];
} else {
$entries[] = $entry;
}
}
if ($modified && !$this->save($key, serialize($entries))) {
throw new \RuntimeException('Unable to store the metadata.');
}
}
/**
* Determines whether two Request HTTP header sets are non-varying based on
* the vary response header value provided.
*
* @param string|null $vary A Response vary header
* @param array $env1 A Request HTTP header array
* @param array $env2 A Request HTTP header array
*/
private function requestsMatch(?string $vary, array $env1, array $env2): bool
{
if (empty($vary)) {
return true;
}
foreach (preg_split('/[\s,]+/', $vary) as $header) {
$key = str_replace('_', '-', strtolower($header));
$v1 = $env1[$key] ?? null;
$v2 = $env2[$key] ?? null;
if ($v1 !== $v2) {
return false;
}
}
return true;
}
/**
* Gets all data associated with the given key.
*
* Use this method only if you know what you are doing.
*/
private function getMetadata(string $key): array
{
if (!$entries = $this->load($key)) {
return [];
}
return unserialize($entries) ?: [];
}
/**
* Purges data for the given URL.
*
* This method purges both the HTTP and the HTTPS version of the cache entry.
*
* @return bool true if the URL exists with either HTTP or HTTPS scheme and has been purged, false otherwise
*/
public function purge(string $url): bool
{
$http = preg_replace('#^https:#', 'http:', $url);
$https = preg_replace('#^http:#', 'https:', $url);
$purgedHttp = $this->doPurge($http);
$purgedHttps = $this->doPurge($https);
return $purgedHttp || $purgedHttps;
}
/**
* Purges data for the given URL.
*/
private function doPurge(string $url): bool
{
$key = $this->getCacheKey(Request::create($url));
if (isset($this->locks[$key])) {
flock($this->locks[$key], \LOCK_UN);
fclose($this->locks[$key]);
unset($this->locks[$key]);
}
if (is_file($path = $this->getPath($key))) {
unlink($path);
return true;
}
return false;
}
/**
* Loads data for the given key.
*/
private function load(string $key): ?string
{
$path = $this->getPath($key);
return is_file($path) && false !== ($contents = @file_get_contents($path)) ? $contents : null;
}
/**
* Save data for the given key.
*/
private function save(string $key, string $data, bool $overwrite = true): bool
{
$path = $this->getPath($key);
if (!$overwrite && file_exists($path)) {
return true;
}
if (isset($this->locks[$key])) {
$fp = $this->locks[$key];
@ftruncate($fp, 0);
@fseek($fp, 0);
$len = @fwrite($fp, $data);
if (\strlen($data) !== $len) {
@ftruncate($fp, 0);
return false;
}
} else {
if (!is_dir(\dirname($path)) && false === @mkdir(\dirname($path), 0777, true) && !is_dir(\dirname($path))) {
return false;
}
$tmpFile = tempnam(\dirname($path), basename($path));
if (false === $fp = @fopen($tmpFile, 'w')) {
@unlink($tmpFile);
return false;
}
@fwrite($fp, $data);
@fclose($fp);
if ($data != file_get_contents($tmpFile)) {
@unlink($tmpFile);
return false;
}
if (false === @rename($tmpFile, $path)) {
@unlink($tmpFile);
return false;
}
}
@chmod($path, 0666 & ~umask());
return true;
}
/**
* @return string
*/
public function getPath(string $key)
{
return $this->root.\DIRECTORY_SEPARATOR.substr($key, 0, 2).\DIRECTORY_SEPARATOR.substr($key, 2, 2).\DIRECTORY_SEPARATOR.substr($key, 4, 2).\DIRECTORY_SEPARATOR.substr($key, 6);
}
/**
* Generates a cache key for the given Request.
*
* This method should return a key that must only depend on a
* normalized version of the request URI.
*
* If the same URI can have more than one representation, based on some
* headers, use a Vary header to indicate them, and each representation will
* be stored independently under the same cache key.
*/
protected function generateCacheKey(Request $request): string
{
return 'md'.hash('sha256', $request->getUri());
}
/**
* Returns a cache key for the given Request.
*/
private function getCacheKey(Request $request): string
{
if (isset($this->keyCache[$request])) {
return $this->keyCache[$request];
}
return $this->keyCache[$request] = $this->generateCacheKey($request);
}
/**
* Persists the Request HTTP headers.
*/
private function persistRequest(Request $request): array
{
return $request->headers->all();
}
/**
* Persists the Response HTTP headers.
*/
private function persistResponse(Response $response): array
{
$headers = $response->headers->all();
$headers['X-Status'] = [$response->getStatusCode()];
return $headers;
}
/**
* Restores a Response from the HTTP headers and body.
*/
private function restoreResponse(array $headers, ?string $path = null): ?Response
{
$status = $headers['X-Status'][0];
unset($headers['X-Status']);
$content = null;
if (null !== $path) {
$headers['X-Body-File'] = [$path];
unset($headers['x-body-file']);
if ($headers['X-Body-Eval'] ?? $headers['x-body-eval'] ?? false) {
$content = file_get_contents($path);
\assert(HttpCache::BODY_EVAL_BOUNDARY_LENGTH === 24);
if (48 > \strlen($content) || substr($content, -24) !== substr($content, 0, 24)) {
return null;
}
}
}
return new Response($content, $status, $headers);
}
}
AbstractSurrogate.php 0000644 00000011221 15152054541 0010713 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\HttpKernelInterface;
/**
* Abstract class implementing Surrogate capabilities to Request and Response instances.
*
* @author Fabien Potencier <fabien@symfony.com>
* @author Robin Chalas <robin.chalas@gmail.com>
*/
abstract class AbstractSurrogate implements SurrogateInterface
{
protected $contentTypes;
/**
* @deprecated since Symfony 6.3
*/
protected $phpEscapeMap = [
['<?', '<%', '<s', '<S'],
['<?php echo "<?"; ?>', '<?php echo "<%"; ?>', '<?php echo "<s"; ?>', '<?php echo "<S"; ?>'],
];
/**
* @param array $contentTypes An array of content-type that should be parsed for Surrogate information
* (default: text/html, text/xml, application/xhtml+xml, and application/xml)
*/
public function __construct(array $contentTypes = ['text/html', 'text/xml', 'application/xhtml+xml', 'application/xml'])
{
$this->contentTypes = $contentTypes;
}
/**
* Returns a new cache strategy instance.
*/
public function createCacheStrategy(): ResponseCacheStrategyInterface
{
return new ResponseCacheStrategy();
}
public function hasSurrogateCapability(Request $request): bool
{
if (null === $value = $request->headers->get('Surrogate-Capability')) {
return false;
}
return str_contains($value, sprintf('%s/1.0', strtoupper($this->getName())));
}
/**
* @return void
*/
public function addSurrogateCapability(Request $request)
{
$current = $request->headers->get('Surrogate-Capability');
$new = sprintf('symfony="%s/1.0"', strtoupper($this->getName()));
$request->headers->set('Surrogate-Capability', $current ? $current.', '.$new : $new);
}
public function needsParsing(Response $response): bool
{
if (!$control = $response->headers->get('Surrogate-Control')) {
return false;
}
$pattern = sprintf('#content="[^"]*%s/1.0[^"]*"#', strtoupper($this->getName()));
return (bool) preg_match($pattern, $control);
}
public function handle(HttpCache $cache, string $uri, string $alt, bool $ignoreErrors): string
{
$subRequest = Request::create($uri, Request::METHOD_GET, [], $cache->getRequest()->cookies->all(), [], $cache->getRequest()->server->all());
try {
$response = $cache->handle($subRequest, HttpKernelInterface::SUB_REQUEST, true);
if (!$response->isSuccessful() && Response::HTTP_NOT_MODIFIED !== $response->getStatusCode()) {
throw new \RuntimeException(sprintf('Error when rendering "%s" (Status code is %d).', $subRequest->getUri(), $response->getStatusCode()));
}
return $response->getContent();
} catch (\Exception $e) {
if ($alt) {
return $this->handle($cache, $alt, '', $ignoreErrors);
}
if (!$ignoreErrors) {
throw $e;
}
}
return '';
}
/**
* Remove the Surrogate from the Surrogate-Control header.
*
* @return void
*/
protected function removeFromControl(Response $response)
{
if (!$response->headers->has('Surrogate-Control')) {
return;
}
$value = $response->headers->get('Surrogate-Control');
$upperName = strtoupper($this->getName());
if (sprintf('content="%s/1.0"', $upperName) == $value) {
$response->headers->remove('Surrogate-Control');
} elseif (preg_match(sprintf('#,\s*content="%s/1.0"#', $upperName), $value)) {
$response->headers->set('Surrogate-Control', preg_replace(sprintf('#,\s*content="%s/1.0"#', $upperName), '', $value));
} elseif (preg_match(sprintf('#content="%s/1.0",\s*#', $upperName), $value)) {
$response->headers->set('Surrogate-Control', preg_replace(sprintf('#content="%s/1.0",\s*#', $upperName), '', $value));
}
}
protected static function generateBodyEvalBoundary(): string
{
static $cookie;
$cookie = hash('xxh128', $cookie ?? $cookie = random_bytes(16), true);
$boundary = base64_encode($cookie);
\assert(HttpCache::BODY_EVAL_BOUNDARY_LENGTH === \strlen($boundary));
return $boundary;
}
}
StoreInterface.php 0000644 00000004264 15152054541 0010202 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* This code is partially based on the Rack-Cache library by Ryan Tomayko,
* which is released under the MIT license.
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
/**
* Interface implemented by HTTP cache stores.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
interface StoreInterface
{
/**
* Locates a cached Response for the Request provided.
*/
public function lookup(Request $request): ?Response;
/**
* Writes a cache entry to the store for the given Request and Response.
*
* Existing entries are read and any that match the response are removed. This
* method calls write with the new list of cache entries.
*
* @return string The key under which the response is stored
*/
public function write(Request $request, Response $response): string;
/**
* Invalidates all cache entries that match the request.
*
* @return void
*/
public function invalidate(Request $request);
/**
* Locks the cache for a given Request.
*
* @return bool|string true if the lock is acquired, the path to the current lock otherwise
*/
public function lock(Request $request): bool|string;
/**
* Releases the lock for the given Request.
*
* @return bool False if the lock file does not exist or cannot be unlocked, true otherwise
*/
public function unlock(Request $request): bool;
/**
* Returns whether or not a lock exists.
*
* @return bool true if lock exists, false otherwise
*/
public function isLocked(Request $request): bool;
/**
* Purges data for the given URL.
*
* @return bool true if the URL exists and has been purged, false otherwise
*/
public function purge(string $url): bool;
/**
* Cleanups storage.
*
* @return void
*/
public function cleanup();
}
SurrogateInterface.php 0000644 00000004156 15152054541 0011061 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
interface SurrogateInterface
{
/**
* Returns surrogate name.
*/
public function getName(): string;
/**
* Returns a new cache strategy instance.
*/
public function createCacheStrategy(): ResponseCacheStrategyInterface;
/**
* Checks that at least one surrogate has Surrogate capability.
*/
public function hasSurrogateCapability(Request $request): bool;
/**
* Adds Surrogate-capability to the given Request.
*
* @return void
*/
public function addSurrogateCapability(Request $request);
/**
* Adds HTTP headers to specify that the Response needs to be parsed for Surrogate.
*
* This method only adds an Surrogate HTTP header if the Response has some Surrogate tags.
*
* @return void
*/
public function addSurrogateControl(Response $response);
/**
* Checks that the Response needs to be parsed for Surrogate tags.
*/
public function needsParsing(Response $response): bool;
/**
* Renders a Surrogate tag.
*
* @param string|null $alt An alternate URI
* @param string $comment A comment to add as an esi:include tag
*/
public function renderIncludeTag(string $uri, ?string $alt = null, bool $ignoreErrors = true, string $comment = ''): string;
/**
* Replaces a Response Surrogate tags with the included resource content.
*/
public function process(Request $request, Response $response): Response;
/**
* Handles a Surrogate from the cache.
*
* @param string $alt An alternative URI
*
* @throws \RuntimeException
* @throws \Exception
*/
public function handle(HttpCache $cache, string $uri, string $alt, bool $ignoreErrors): string;
}
SubRequestHandler.php 0000644 00000007521 15152054541 0010664 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\IpUtils;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\HttpKernelInterface;
/**
* @author Nicolas Grekas <p@tchwork.com>
*
* @internal
*/
class SubRequestHandler
{
public static function handle(HttpKernelInterface $kernel, Request $request, int $type, bool $catch): Response
{
// save global state related to trusted headers and proxies
$trustedProxies = Request::getTrustedProxies();
$trustedHeaderSet = Request::getTrustedHeaderSet();
// remove untrusted values
$remoteAddr = $request->server->get('REMOTE_ADDR');
if (!$remoteAddr || !IpUtils::checkIp($remoteAddr, $trustedProxies)) {
$trustedHeaders = [
'FORWARDED' => $trustedHeaderSet & Request::HEADER_FORWARDED,
'X_FORWARDED_FOR' => $trustedHeaderSet & Request::HEADER_X_FORWARDED_FOR,
'X_FORWARDED_HOST' => $trustedHeaderSet & Request::HEADER_X_FORWARDED_HOST,
'X_FORWARDED_PROTO' => $trustedHeaderSet & Request::HEADER_X_FORWARDED_PROTO,
'X_FORWARDED_PORT' => $trustedHeaderSet & Request::HEADER_X_FORWARDED_PORT,
'X_FORWARDED_PREFIX' => $trustedHeaderSet & Request::HEADER_X_FORWARDED_PREFIX,
];
foreach (array_filter($trustedHeaders) as $name => $key) {
$request->headers->remove($name);
$request->server->remove('HTTP_'.$name);
}
}
// compute trusted values, taking any trusted proxies into account
$trustedIps = [];
$trustedValues = [];
foreach (array_reverse($request->getClientIps()) as $ip) {
$trustedIps[] = $ip;
$trustedValues[] = sprintf('for="%s"', $ip);
}
if ($ip !== $remoteAddr) {
$trustedIps[] = $remoteAddr;
$trustedValues[] = sprintf('for="%s"', $remoteAddr);
}
// set trusted values, reusing as much as possible the global trusted settings
if (Request::HEADER_FORWARDED & $trustedHeaderSet) {
$trustedValues[0] .= sprintf(';host="%s";proto=%s', $request->getHttpHost(), $request->getScheme());
$request->headers->set('Forwarded', $v = implode(', ', $trustedValues));
$request->server->set('HTTP_FORWARDED', $v);
}
if (Request::HEADER_X_FORWARDED_FOR & $trustedHeaderSet) {
$request->headers->set('X-Forwarded-For', $v = implode(', ', $trustedIps));
$request->server->set('HTTP_X_FORWARDED_FOR', $v);
} elseif (!(Request::HEADER_FORWARDED & $trustedHeaderSet)) {
Request::setTrustedProxies($trustedProxies, $trustedHeaderSet | Request::HEADER_X_FORWARDED_FOR);
$request->headers->set('X-Forwarded-For', $v = implode(', ', $trustedIps));
$request->server->set('HTTP_X_FORWARDED_FOR', $v);
}
// fix the client IP address by setting it to 127.0.0.1,
// which is the core responsibility of this method
$request->server->set('REMOTE_ADDR', '127.0.0.1');
// ensure 127.0.0.1 is set as trusted proxy
if (!IpUtils::checkIp('127.0.0.1', $trustedProxies)) {
Request::setTrustedProxies(array_merge($trustedProxies, ['127.0.0.1']), Request::getTrustedHeaderSet());
}
try {
return $kernel->handle($request, $type, $catch);
} finally {
// restore global state
Request::setTrustedProxies($trustedProxies, $trustedHeaderSet);
}
}
}
Esi.php 0000644 00000006363 15152054541 0006007 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
/**
* Esi implements the ESI capabilities to Request and Response instances.
*
* For more information, read the following W3C notes:
*
* * ESI Language Specification 1.0 (http://www.w3.org/TR/esi-lang)
*
* * Edge Architecture Specification (http://www.w3.org/TR/edge-arch)
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class Esi extends AbstractSurrogate
{
public function getName(): string
{
return 'esi';
}
/**
* @return void
*/
public function addSurrogateControl(Response $response)
{
if (str_contains($response->getContent(), '<esi:include')) {
$response->headers->set('Surrogate-Control', 'content="ESI/1.0"');
}
}
public function renderIncludeTag(string $uri, ?string $alt = null, bool $ignoreErrors = true, string $comment = ''): string
{
$html = sprintf('<esi:include src="%s"%s%s />',
$uri,
$ignoreErrors ? ' onerror="continue"' : '',
$alt ? sprintf(' alt="%s"', $alt) : ''
);
if (!empty($comment)) {
return sprintf("<esi:comment text=\"%s\" />\n%s", $comment, $html);
}
return $html;
}
public function process(Request $request, Response $response): Response
{
$type = $response->headers->get('Content-Type');
if (empty($type)) {
$type = 'text/html';
}
$parts = explode(';', $type);
if (!\in_array($parts[0], $this->contentTypes)) {
return $response;
}
// we don't use a proper XML parser here as we can have ESI tags in a plain text response
$content = $response->getContent();
$content = preg_replace('#<esi\:remove>.*?</esi\:remove>#s', '', $content);
$content = preg_replace('#<esi\:comment[^>]+>#s', '', $content);
$boundary = self::generateBodyEvalBoundary();
$chunks = preg_split('#<esi\:include\s+(.*?)\s*(?:/|</esi\:include)>#', $content, -1, \PREG_SPLIT_DELIM_CAPTURE);
$i = 1;
while (isset($chunks[$i])) {
$options = [];
preg_match_all('/(src|onerror|alt)="([^"]*?)"/', $chunks[$i], $matches, \PREG_SET_ORDER);
foreach ($matches as $set) {
$options[$set[1]] = $set[2];
}
if (!isset($options['src'])) {
throw new \RuntimeException('Unable to process an ESI tag without a "src" attribute.');
}
$chunks[$i] = $boundary.$options['src']."\n".($options['alt'] ?? '')."\n".('continue' === ($options['onerror'] ?? ''))."\n";
$i += 2;
}
$content = $boundary.implode('', $chunks).$boundary;
$response->setContent($content);
$response->headers->set('X-Body-Eval', 'ESI');
// remove ESI/1.0 from the Surrogate-Control header
$this->removeFromControl($response);
return $response;
}
}
Ssi.php 0000644 00000005035 15152054541 0006020 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
/**
* Ssi implements the SSI capabilities to Request and Response instances.
*
* @author Sebastian Krebs <krebs.seb@gmail.com>
*/
class Ssi extends AbstractSurrogate
{
public function getName(): string
{
return 'ssi';
}
/**
* @return void
*/
public function addSurrogateControl(Response $response)
{
if (str_contains($response->getContent(), '<!--#include')) {
$response->headers->set('Surrogate-Control', 'content="SSI/1.0"');
}
}
public function renderIncludeTag(string $uri, ?string $alt = null, bool $ignoreErrors = true, string $comment = ''): string
{
return sprintf('<!--#include virtual="%s" -->', $uri);
}
public function process(Request $request, Response $response): Response
{
$type = $response->headers->get('Content-Type');
if (empty($type)) {
$type = 'text/html';
}
$parts = explode(';', $type);
if (!\in_array($parts[0], $this->contentTypes)) {
return $response;
}
// we don't use a proper XML parser here as we can have SSI tags in a plain text response
$content = $response->getContent();
$boundary = self::generateBodyEvalBoundary();
$chunks = preg_split('#<!--\#include\s+(.*?)\s*-->#', $content, -1, \PREG_SPLIT_DELIM_CAPTURE);
$i = 1;
while (isset($chunks[$i])) {
$options = [];
preg_match_all('/(virtual)="([^"]*?)"/', $chunks[$i], $matches, \PREG_SET_ORDER);
foreach ($matches as $set) {
$options[$set[1]] = $set[2];
}
if (!isset($options['virtual'])) {
throw new \RuntimeException('Unable to process an SSI tag without a "virtual" attribute.');
}
$chunks[$i] = $boundary.$options['virtual']."\n\n\n";
$i += 2;
}
$content = $boundary.implode('', $chunks).$boundary;
$response->setContent($content);
$response->headers->set('X-Body-Eval', 'SSI');
// remove SSI/1.0 from the Surrogate-Control header
$this->removeFromControl($response);
return $response;
}
}
HttpCache.php 0000644 00000065542 15152054541 0007136 0 ustar 00 <?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
/*
* This code is partially based on the Rack-Cache library by Ryan Tomayko,
* which is released under the MIT license.
* (based on commit 02d2b48d75bcb63cf1c0c7149c077ad256542801)
*/
namespace Symfony\Component\HttpKernel\HttpCache;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\HttpKernelInterface;
use Symfony\Component\HttpKernel\TerminableInterface;
/**
* Cache provides HTTP caching.
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class HttpCache implements HttpKernelInterface, TerminableInterface
{
public const BODY_EVAL_BOUNDARY_LENGTH = 24;
private HttpKernelInterface $kernel;
private StoreInterface $store;
private Request $request;
private ?SurrogateInterface $surrogate;
private ?ResponseCacheStrategyInterface $surrogateCacheStrategy = null;
private array $options = [];
private array $traces = [];
/**
* Constructor.
*
* The available options are:
*
* * debug If true, exceptions are thrown when things go wrong. Otherwise, the cache
* will try to carry on and deliver a meaningful response.
*
* * trace_level May be one of 'none', 'short' and 'full'. For 'short', a concise trace of the
* main request will be added as an HTTP header. 'full' will add traces for all
* requests (including ESI subrequests). (default: 'full' if in debug; 'none' otherwise)
*
* * trace_header Header name to use for traces. (default: X-Symfony-Cache)
*
* * default_ttl The number of seconds that a cache entry should be considered
* fresh when no explicit freshness information is provided in
* a response. Explicit Cache-Control or Expires headers
* override this value. (default: 0)
*
* * private_headers Set of request headers that trigger "private" cache-control behavior
* on responses that don't explicitly state whether the response is
* public or private via a Cache-Control directive. (default: Authorization and Cookie)
*
* * skip_response_headers Set of response headers that are never cached even if a response is cacheable (public).
* (default: Set-Cookie)
*
* * allow_reload Specifies whether the client can force a cache reload by including a
* Cache-Control "no-cache" directive in the request. Set it to ``true``
* for compliance with RFC 2616. (default: false)
*
* * allow_revalidate Specifies whether the client can force a cache revalidate by including
* a Cache-Control "max-age=0" directive in the request. Set it to ``true``
* for compliance with RFC 2616. (default: false)
*
* * stale_while_revalidate Specifies the default number of seconds (the granularity is the second as the
* Response TTL precision is a second) during which the cache can immediately return
* a stale response while it revalidates it in the background (default: 2).
* This setting is overridden by the stale-while-revalidate HTTP Cache-Control
* extension (see RFC 5861).
*
* * stale_if_error Specifies the default number of seconds (the granularity is the second) during which
* the cache can serve a stale response when an error is encountered (default: 60).
* This setting is overridden by the stale-if-error HTTP Cache-Control extension
* (see RFC 5861).
*
* * terminate_on_cache_hit Specifies if the kernel.terminate event should be dispatched even when the cache
* was hit (default: true).
* Unless your application needs to process events on cache hits, it is recommended
* to set this to false to avoid having to bootstrap the Symfony framework on a cache hit.
*/
public function __construct(HttpKernelInterface $kernel, StoreInterface $store, ?SurrogateInterface $surrogate = null, array $options = [])
{
$this->store = $store;
$this->kernel = $kernel;
$this->surrogate = $surrogate;
// needed in case there is a fatal error because the backend is too slow to respond
register_shutdown_function($this->store->cleanup(...));
$this->options = array_merge([
'debug' => false,
'default_ttl' => 0,
'private_headers' => ['Authorization', 'Cookie'],
'skip_response_headers' => ['Set-Cookie'],
'allow_reload' => false,
'allow_revalidate' => false,
'stale_while_revalidate' => 2,
'stale_if_error' => 60,
'trace_level' => 'none',
'trace_header' => 'X-Symfony-Cache',
'terminate_on_cache_hit' => true,
], $options);
if (!isset($options['trace_level'])) {
$this->options['trace_level'] = $this->options['debug'] ? 'full' : 'none';
}
}
/**
* Gets the current store.
*/
public function getStore(): StoreInterface
{
return $this->store;
}
/**
* Returns an array of events that took place during processing of the last request.
*/
public function getTraces(): array
{
return $this->traces;
}
private function addTraces(Response $response): void
{
$traceString = null;
if ('full' === $this->options['trace_level']) {
$traceString = $this->getLog();
}
if ('short' === $this->options['trace_level'] && $masterId = array_key_first($this->traces)) {
$traceString = implode('/', $this->traces[$masterId]);
}
if (null !== $traceString) {
$response->headers->add([$this->options['trace_header'] => $traceString]);
}
}
/**
* Returns a log message for the events of the last request processing.
*/
public function getLog(): string
{
$log = [];
foreach ($this->traces as $request => $traces) {
$log[] = sprintf('%s: %s', $request, implode(', ', $traces));
}
return implode('; ', $log);
}
/**
* Gets the Request instance associated with the main request.
*/
public function getRequest(): Request
{
return $this->request;
}
/**
* Gets the Kernel instance.
*/
public function getKernel(): HttpKernelInterface
{
return $this->kernel;
}
/**
* Gets the Surrogate instance.
*
* @throws \LogicException
*/
public function getSurrogate(): SurrogateInterface
{
return $this->surrogate;
}
public function handle(Request $request, int $type = HttpKernelInterface::MAIN_REQUEST, bool $catch = true): Response
{
// FIXME: catch exceptions and implement a 500 error page here? -> in Varnish, there is a built-in error page mechanism
if (HttpKernelInterface::MAIN_REQUEST === $type) {
$this->traces = [];
// Keep a clone of the original request for surrogates so they can access it.
// We must clone here to get a separate instance because the application will modify the request during
// the application flow (we know it always does because we do ourselves by setting REMOTE_ADDR to 127.0.0.1
// and adding the X-Forwarded-For header, see HttpCache::forward()).
$this->request = clone $request;
if (null !== $this->surrogate) {
$this->surrogateCacheStrategy = $this->surrogate->createCacheStrategy();
}
}
$this->traces[$this->getTraceKey($request)] = [];
if (!$request->isMethodSafe()) {
$response = $this->invalidate($request, $catch);
} elseif ($request->headers->has('expect') || !$request->isMethodCacheable()) {
$response = $this->pass($request, $catch);
} elseif ($this->options['allow_reload'] && $request->isNoCache()) {
/*
If allow_reload is configured and the client requests "Cache-Control: no-cache",
reload the cache by fetching a fresh response and caching it (if possible).
*/
$this->record($request, 'reload');
$response = $this->fetch($request, $catch);
} else {
$response = $this->lookup($request, $catch);
}
$this->restoreResponseBody($request, $response);
if (HttpKernelInterface::MAIN_REQUEST === $type) {
$this->addTraces($response);
}
if (null !== $this->surrogate) {
if (HttpKernelInterface::MAIN_REQUEST === $type) {
$this->surrogateCacheStrategy->update($response);
} else {
$this->surrogateCacheStrategy->add($response);
}
}
$response->prepare($request);
$response->isNotModified($request);
return $response;
}
/**
* @return void
*/
public function terminate(Request $request, Response $response)
{
// Do not call any listeners in case of a cache hit.
// This ensures identical behavior as if you had a separate
// reverse caching proxy such as Varnish and the like.
if ($this->options['terminate_on_cache_hit']) {
trigger_deprecation('symfony/http-kernel', '6.2', 'Setting "terminate_on_cache_hit" to "true" is deprecated and will be changed to "false" in Symfony 7.0.');
} elseif (\in_array('fresh', $this->traces[$this->getTraceKey($request)] ?? [], true)) {
return;
}
if ($this->getKernel() instanceof TerminableInterface) {
$this->getKernel()->terminate($request, $response);
}
}
/**
* Forwards the Request to the backend without storing the Response in the cache.
*
* @param bool $catch Whether to process exceptions
*/
protected function pass(Request $request, bool $catch = false): Response
{
$this->record($request, 'pass');
return $this->forward($request, $catch);
}
/**
* Invalidates non-safe methods (like POST, PUT, and DELETE).
*
* @param bool $catch Whether to process exceptions
*
* @throws \Exception
*
* @see RFC2616 13.10
*/
protected function invalidate(Request $request, bool $catch = false): Response
{
$response = $this->pass($request, $catch);
// invalidate only when the response is successful
if ($response->isSuccessful() || $response->isRedirect()) {
try {
$this->store->invalidate($request);
// As per the RFC, invalidate Location and Content-Location URLs if present
foreach (['Location', 'Content-Location'] as $header) {
if ($uri = $response->headers->get($header)) {
$subRequest = Request::create($uri, 'get', [], [], [], $request->server->all());
$this->store->invalidate($subRequest);
}
}
$this->record($request, 'invalidate');
} catch (\Exception $e) {
$this->record($request, 'invalidate-failed');
if ($this->options['debug']) {
throw $e;
}
}
}
return $response;
}
/**
* Lookups a Response from the cache for the given Request.
*
* When a matching cache entry is found and is fresh, it uses it as the
* response without forwarding any request to the backend. When a matching
* cache entry is found but is stale, it attempts to "validate" the entry with
* the backend using conditional GET. When no matching cache entry is found,
* it triggers "miss" processing.
*
* @param bool $catch Whether to process exceptions
*
* @throws \Exception
*/
protected function lookup(Request $request, bool $catch = false): Response
{
try {
$entry = $this->store->lookup($request);
} catch (\Exception $e) {
$this->record($request, 'lookup-failed');
if ($this->options['debug']) {
throw $e;
}
return $this->pass($request, $catch);
}
if (null === $entry) {
$this->record($request, 'miss');
return $this->fetch($request, $catch);
}
if (!$this->isFreshEnough($request, $entry)) {
$this->record($request, 'stale');
return $this->validate($request, $entry, $catch);
}
if ($entry->headers->hasCacheControlDirective('no-cache')) {
return $this->validate($request, $entry, $catch);
}
$this->record($request, 'fresh');
$entry->headers->set('Age', $entry->getAge());
return $entry;
}
/**
* Validates that a cache entry is fresh.
*
* The original request is used as a template for a conditional
* GET request with the backend.
*
* @param bool $catch Whether to process exceptions
*/
protected function validate(Request $request, Response $entry, bool $catch = false): Response
{
$subRequest = clone $request;
// send no head requests because we want content
if ('HEAD' === $request->getMethod()) {
$subRequest->setMethod('GET');
}
// add our cached last-modified validator
if ($entry->headers->has('Last-Modified')) {
$subRequest->headers->set('If-Modified-Since', $entry->headers->get('Last-Modified'));
}
// Add our cached etag validator to the environment.
// We keep the etags from the client to handle the case when the client
// has a different private valid entry which is not cached here.
$cachedEtags = $entry->getEtag() ? [$entry->getEtag()] : [];
$requestEtags = $request->getETags();
if ($etags = array_unique(array_merge($cachedEtags, $requestEtags))) {
$subRequest->headers->set('If-None-Match', implode(', ', $etags));
}
$response = $this->forward($subRequest, $catch, $entry);
if (304 == $response->getStatusCode()) {
$this->record($request, 'valid');
// return the response and not the cache entry if the response is valid but not cached
$etag = $response->getEtag();
if ($etag && \in_array($etag, $requestEtags) && !\in_array($etag, $cachedEtags)) {
return $response;
}
$entry = clone $entry;
$entry->headers->remove('Date');
foreach (['Date', 'Expires', 'Cache-Control', 'ETag', 'Last-Modified'] as $name) {
if ($response->headers->has($name)) {
$entry->headers->set($name, $response->headers->get($name));
}
}
$response = $entry;
} else {
$this->record($request, 'invalid');
}
if ($response->isCacheable()) {
$this->store($request, $response);
}
return $response;
}
/**
* Unconditionally fetches a fresh response from the backend and
* stores it in the cache if is cacheable.
*
* @param bool $catch Whether to process exceptions
*/
protected function fetch(Request $request, bool $catch = false): Response
{
$subRequest = clone $request;
// send no head requests because we want content
if ('HEAD' === $request->getMethod()) {
$subRequest->setMethod('GET');
}
// avoid that the backend sends no content
$subRequest->headers->remove('If-Modified-Since');
$subRequest->headers->remove('If-None-Match');
$response = $this->forward($subRequest, $catch);
if ($response->isCacheable()) {
$this->store($request, $response);
}
return $response;
}
/**
* Forwards the Request to the backend and returns the Response.
*
* All backend requests (cache passes, fetches, cache validations)
* run through this method.
*
* @param bool $catch Whether to catch exceptions or not
* @param Response|null $entry A Response instance (the stale entry if present, null otherwise)
*
* @return Response
*/
protected function forward(Request $request, bool $catch = false, ?Response $entry = null)
{
$this->surrogate?->addSurrogateCapability($request);
// always a "master" request (as the real master request can be in cache)
$response = SubRequestHandler::handle($this->kernel, $request, HttpKernelInterface::MAIN_REQUEST, $catch);
/*
* Support stale-if-error given on Responses or as a config option.
* RFC 7234 summarizes in Section 4.2.4 (but also mentions with the individual
* Cache-Control directives) that
*
* A cache MUST NOT generate a stale response if it is prohibited by an
* explicit in-protocol directive (e.g., by a "no-store" or "no-cache"
* cache directive, a "must-revalidate" cache-response-directive, or an
* applicable "s-maxage" or "proxy-revalidate" cache-response-directive;
* see Section 5.2.2).
*
* https://tools.ietf.org/html/rfc7234#section-4.2.4
*
* We deviate from this in one detail, namely that we *do* serve entries in the
* stale-if-error case even if they have a `s-maxage` Cache-Control directive.
*/
if (null !== $entry
&& \in_array($response->getStatusCode(), [500, 502, 503, 504])
&& !$entry->headers->hasCacheControlDirective('no-cache')
&& !$entry->mustRevalidate()
) {
if (null === $age = $entry->headers->getCacheControlDirective('stale-if-error')) {
$age = $this->options['stale_if_error'];
}
/*
* stale-if-error gives the (extra) time that the Response may be used *after* it has become stale.
* So we compare the time the $entry has been sitting in the cache already with the
* time it was fresh plus the allowed grace period.
*/
if ($entry->getAge() <= $entry->getMaxAge() + $age) {
$this->record($request, 'stale-if-error');
return $entry;
}
}
/*
RFC 7231 Sect. 7.1.1.2 says that a server that does not have a reasonably accurate
clock MUST NOT send a "Date" header, although it MUST send one in most other cases
except for 1xx or 5xx responses where it MAY do so.
Anyway, a client that received a message without a "Date" header MUST add it.
*/
if (!$response->headers->has('Date')) {
$response->setDate(\DateTimeImmutable::createFromFormat('U', time()));
}
$this->processResponseBody($request, $response);
if ($this->isPrivateRequest($request) && !$response->headers->hasCacheControlDirective('public')) {
$response->setPrivate();
} elseif ($this->options['default_ttl'] > 0 && null === $response->getTtl() && !$response->headers->getCacheControlDirective('must-revalidate')) {
$response->setTtl($this->options['default_ttl']);
}
return $response;
}
/**
* Checks whether the cache entry is "fresh enough" to satisfy the Request.
*/
protected function isFreshEnough(Request $request, Response $entry): bool
{
if (!$entry->isFresh()) {
return $this->lock($request, $entry);
}
if ($this->options['allow_revalidate'] && null !== $maxAge = $request->headers->getCacheControlDirective('max-age')) {
return $maxAge > 0 && $maxAge >= $entry->getAge();
}
return true;
}
/**
* Locks a Request during the call to the backend.
*
* @return bool true if the cache entry can be returned even if it is staled, false otherwise
*/
protected function lock(Request $request, Response $entry): bool
{
// try to acquire a lock to call the backend
$lock = $this->store->lock($request);
if (true === $lock) {
// we have the lock, call the backend
return false;
}
// there is already another process calling the backend
// May we serve a stale response?
if ($this->mayServeStaleWhileRevalidate($entry)) {
$this->record($request, 'stale-while-revalidate');
return true;
}
// wait for the lock to be released
if ($this->waitForLock($request)) {
// replace the current entry with the fresh one
$new = $this->lookup($request);
$entry->headers = $new->headers;
$entry->setContent($new->getContent());
$entry->setStatusCode($new->getStatusCode());
$entry->setProtocolVersion($new->getProtocolVersion());
foreach ($new->headers->getCookies() as $cookie) {
$entry->headers->setCookie($cookie);
}
} else {
// backend is slow as hell, send a 503 response (to avoid the dog pile effect)
$entry->setStatusCode(503);
$entry->setContent('503 Service Unavailable');
$entry->headers->set('Retry-After', 10);
}
return true;
}
/**
* Writes the Response to the cache.
*
* @return void
*
* @throws \Exception
*/
protected function store(Request $request, Response $response)
{
try {
$restoreHeaders = [];
foreach ($this->options['skip_response_headers'] as $header) {
if (!$response->headers->has($header)) {
continue;
}
$restoreHeaders[$header] = $response->headers->all($header);
$response->headers->remove($header);
}
$this->store->write($request, $response);
$this->record($request, 'store');
$response->headers->set('Age', $response->getAge());
} catch (\Exception $e) {
$this->record($request, 'store-failed');
if ($this->options['debug']) {
throw $e;
}
} finally {
foreach ($restoreHeaders as $header => $values) {
$response->headers->set($header, $values);
}
}
// now that the response is cached, release the lock
$this->store->unlock($request);
}
/**
* Restores the Response body.
*/
private function restoreResponseBody(Request $request, Response $response): void
{
if ($response->headers->has('X-Body-Eval')) {
\assert(self::BODY_EVAL_BOUNDARY_LENGTH === 24);
ob_start();
$content = $response->getContent();
$boundary = substr($content, 0, 24);
$j = strpos($content, $boundary, 24);
echo substr($content, 24, $j - 24);
$i = $j + 24;
while (false !== $j = strpos($content, $boundary, $i)) {
[$uri, $alt, $ignoreErrors, $part] = explode("\n", substr($content, $i, $j - $i), 4);
$i = $j + 24;
echo $this->surrogate->handle($this, $uri, $alt, $ignoreErrors);
echo $part;
}
$response->setContent(ob_get_clean());
$response->headers->remove('X-Body-Eval');
if (!$response->headers->has('Transfer-Encoding')) {
$response->headers->set('Content-Length', \strlen($response->getContent()));
}
} elseif ($response->headers->has('X-Body-File')) {
// Response does not include possibly dynamic content (ESI, SSI), so we need
// not handle the content for HEAD requests
if (!$request->isMethod('HEAD')) {
$response->setContent(file_get_contents($response->headers->get('X-Body-File')));
}
} else {
return;
}
$response->headers->remove('X-Body-File');
}
/**
* @return void
*/
protected function processResponseBody(Request $request, Response $response)
{
if ($this->surrogate?->needsParsing($response)) {
$this->surrogate->process($request, $response);
}
}
/**
* Checks if the Request includes authorization or other sensitive information
* that should cause the Response to be considered private by default.
*/
private function isPrivateRequest(Request $request): bool
{
foreach ($this->options['private_headers'] as $key) {
$key = strtolower(str_replace('HTTP_', '', $key));
if ('cookie' === $key) {
if (\count($request->cookies->all())) {
return true;
}
} elseif ($request->headers->has($key)) {
return true;
}
}
return false;
}
/**
* Records that an event took place.
*/
private function record(Request $request, string $event): void
{
$this->traces[$this->getTraceKey($request)][] = $event;
}
/**
* Calculates the key we use in the "trace" array for a given request.
*/
private function getTraceKey(Request $request): string
{
$path = $request->getPathInfo();
if ($qs = $request->getQueryString()) {
$path .= '?'.$qs;
}
return $request->getMethod().' '.$path;
}
/**
* Checks whether the given (cached) response may be served as "stale" when a revalidation
* is currently in progress.
*/
private function mayServeStaleWhileRevalidate(Response $entry): bool
{
$timeout = $entry->headers->getCacheControlDirective('stale-while-revalidate');
$timeout ??= $this->options['stale_while_revalidate'];
$age = $entry->getAge();
$maxAge = $entry->getMaxAge() ?? 0;
$ttl = $maxAge - $age;
return abs($ttl) < $timeout;
}
/**
* Waits for the store to release a locked entry.
*/
private function waitForLock(Request $request): bool
{
$wait = 0;
while ($this->store->isLocked($request) && $wait < 100) {
usleep(50000);
++$wait;
}
return $wait < 100;
}
}
