Merge pull request api-platform#2865 from jocel1/varnish-purge-by-chunk

send Varnish BAN requests with smaller headers
Oipnet · Mar 10, 2020 · 3b8dc7d · 3b8dc7d
2 parents 842ab30 + c6055be
commit 3b8dc7d
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Showing 6 changed files with 59 additions and 2 deletions.
diff --git a/src/Bridge/Symfony/Bundle/DependencyInjection/ApiPlatformExtension.php b/src/Bridge/Symfony/Bundle/DependencyInjection/ApiPlatformExtension.php
@@ -186,6 +186,7 @@ private function registerCommonConfiguration(ContainerBuilder $container, array
         $container->setParameter('api_platform.http_cache.shared_max_age', $config['http_cache']['shared_max_age']);
         $container->setParameter('api_platform.http_cache.vary', $config['http_cache']['vary']);
         $container->setParameter('api_platform.http_cache.public', $config['http_cache']['public']);
+        $container->setParameter('api_platform.http_cache.invalidation.max_header_length', $config['http_cache']['invalidation']['max_header_length']);
 
         $container->setAlias('api_platform.operation_path_resolver.default', $config['default_operation_path_resolver']);
         $container->setAlias('api_platform.path_segment_name_generator', $config['path_segment_name_generator']);
@@ -532,7 +533,8 @@ private function registerHttpCacheConfiguration(ContainerBuilder $container, arr
             $definitions[] = $definition;
         }
 
-        $container->getDefinition('api_platform.http_cache.purger.varnish')->addArgument($definitions);
+        $container->getDefinition('api_platform.http_cache.purger.varnish')->setArguments([$definitions,
+            $config['http_cache']['invalidation']['max_header_length'], ]);
         $container->setAlias('api_platform.http_cache.purger', 'api_platform.http_cache.purger.varnish');
     }
 

diff --git a/src/Bridge/Symfony/Bundle/DependencyInjection/Configuration.php b/src/Bridge/Symfony/Bundle/DependencyInjection/Configuration.php
@@ -375,6 +375,10 @@ private function addHttpCacheSection(ArrayNodeDefinition $rootNode): void
                                     ->prototype('scalar')->end()
                                     ->info('URLs of the Varnish servers to purge using cache tags when a resource is updated.')
                                 ->end()
+                                ->integerNode('max_header_length')
+                                    ->defaultValue(7500)
+                                    ->info('Max header length supported by the server')
+                                ->end()
                                 ->variableNode('request_options')
                                     ->defaultValue([])
                                     ->validate()

diff --git a/src/HttpCache/VarnishPurger.php b/src/HttpCache/VarnishPurger.php
@@ -25,13 +25,41 @@
 final class VarnishPurger implements PurgerInterface
 {
     private $clients;
+    private $maxHeaderLength;
 
     /**
      * @param ClientInterface[] $clients
      */
-    public function __construct(array $clients)
+    public function __construct(array $clients, int $maxHeaderLength = 7500)
     {
         $this->clients = $clients;
+        $this->maxHeaderLength = $maxHeaderLength;
+    }
+
+    /**
+     * Calculate how many tags fit into the header.
+     *
+     * This assumes that the tags are separated by one character.
+     *
+     * From https://github.com/FriendsOfSymfony/FOSHttpCache/blob/2.8.0/src/ProxyClient/HttpProxyClient.php#L137
+     *
+     * @param string[] $escapedTags
+     * @param string   $glue        The concatenation string to use
+     *
+     * @return int Number of tags per tag invalidation request
+     */
+    private function determineTagsPerHeader(array $escapedTags, string $glue): int
+    {
+        if (mb_strlen(implode($glue, $escapedTags)) < $this->maxHeaderLength) {
+            return \count($escapedTags);
+        }
+        /*
+         * estimate the amount of tags to invalidate by dividing the max
+         * header length by the largest tag (minus the glue length)
+         */
+        $tagsize = max(array_map('mb_strlen', $escapedTags));
+
+        return (int) floor($this->maxHeaderLength / ($tagsize + \strlen($glue))) ?: 1;
     }
 
     /**
@@ -43,6 +71,16 @@ public function purge(array $iris)
             return;
         }
 
+        $chunkSize = $this->determineTagsPerHeader($iris, '|');
+
+        $irisChunks = array_chunk($iris, $chunkSize);
+        foreach ($irisChunks as $irisChunk) {
+            $this->purgeRequest($irisChunk);
+        }
+    }
+
+    private function purgeRequest(array $iris)
+    {
         // Create the regex to purge all tags in just one request
         $parts = array_map(function ($iri) {
             return sprintf('(^|\,)%s($|\,)', preg_quote($iri));

diff --git a/tests/Bridge/Symfony/Bundle/DependencyInjection/ApiPlatformExtensionTest.php b/tests/Bridge/Symfony/Bundle/DependencyInjection/ApiPlatformExtensionTest.php
@@ -858,6 +858,7 @@ private function getPartialContainerBuilderProphecy($configuration = null)
             'api_platform.http_cache.shared_max_age' => null,
             'api_platform.http_cache.vary' => ['Accept'],
             'api_platform.http_cache.public' => null,
+            'api_platform.http_cache.invalidation.max_header_length' => 7500,
             'api_platform.defaults' => ['attributes' => []],
             'api_platform.enable_entrypoint' => true,
             'api_platform.enable_docs' => true,

diff --git a/tests/Bridge/Symfony/Bundle/DependencyInjection/ConfigurationTest.php b/tests/Bridge/Symfony/Bundle/DependencyInjection/ConfigurationTest.php
@@ -182,6 +182,7 @@ private function runDefaultConfigTests(array $doctrineIntegrationsToLoad = ['orm
                     'enabled' => false,
                     'varnish_urls' => [],
                     'request_options' => [],
+                    'max_header_length' => 7500,
                 ],
                 'etag' => true,
                 'max_age' => null,

diff --git a/tests/HttpCache/VarnishPurgerTest.php b/tests/HttpCache/VarnishPurgerTest.php
@@ -33,9 +33,20 @@ public function testPurge()
         $clientProphecy2->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '(^|\,)/foo($|\,)']])->willReturn(new Response())->shouldBeCalled();
         $clientProphecy2->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '((^|\,)/foo($|\,))|((^|\,)/bar($|\,))']])->willReturn(new Response())->shouldBeCalled();
 
+        $clientProphecy3 = $this->prophesize(ClientInterface::class);
+        $clientProphecy3->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '(^|\,)/foo($|\,)']])->willReturn(new Response())->shouldBeCalled();
+        $clientProphecy3->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '(^|\,)/bar($|\,)']])->willReturn(new Response())->shouldBeCalled();
+
+        $clientProphecy4 = $this->prophesize(ClientInterface::class);
+        $clientProphecy4->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '(^|\,)/foo($|\,)']])->willReturn(new Response())->shouldBeCalled();
+        $clientProphecy4->request('BAN', '', ['headers' => ['ApiPlatform-Ban-Regex' => '(^|\,)/bar($|\,)']])->willReturn(new Response())->shouldBeCalled();
+
         $purger = new VarnishPurger([$clientProphecy1->reveal(), $clientProphecy2->reveal()]);
         $purger->purge(['/foo']);
         $purger->purge(['/foo' => '/foo', '/bar' => '/bar']);
+
+        $purger = new VarnishPurger([$clientProphecy3->reveal(), $clientProphecy4->reveal()], 5);
+        $purger->purge(['/foo' => '/foo', '/bar' => '/bar']);
     }
 
     public function testEmptyTags()