FriendsOfSymfony /
FOSHttpCacheBundle
Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like FOSHttpCacheExtension often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use FOSHttpCacheExtension, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 32 | class FOSHttpCacheExtension extends Extension |
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| 33 | { |
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| 34 | /** |
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| 35 | * {@inheritdoc} |
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| 36 | */ |
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| 37 | 27 | public function getConfiguration(array $config, ContainerBuilder $container) |
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| 41 | |||
| 42 | /** |
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| 43 | * {@inheritdoc} |
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| 44 | */ |
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| 45 | 27 | public function load(array $configs, ContainerBuilder $container) |
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| 46 | { |
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| 47 | 27 | $configuration = $this->getConfiguration($configs, $container); |
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| 48 | 27 | $config = $this->processConfiguration($configuration, $configs); |
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| 49 | |||
| 50 | 27 | $loader = new XmlFileLoader($container, new FileLocator(__DIR__.'/../Resources/config')); |
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| 51 | 27 | $loader->load('matcher.xml'); |
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| 52 | |||
| 53 | 27 | if ($config['debug']['enabled'] || (!empty($config['cache_control']))) { |
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| 54 | 7 | $debugHeader = $config['debug']['enabled'] ? $config['debug']['header'] : false; |
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| 55 | 7 | $container->setParameter($this->getAlias().'.debug_header', $debugHeader); |
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| 56 | 7 | $loader->load('cache_control_listener.xml'); |
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| 57 | } |
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| 58 | |||
| 59 | 27 | $this->loadCacheable($container, $config['cacheable']); |
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| 60 | |||
| 61 | 27 | if (!empty($config['cache_control'])) { |
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| 62 | 7 | $this->loadCacheControl($container, $config['cache_control']); |
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| 63 | } |
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| 64 | |||
| 65 | 26 | if (isset($config['proxy_client'])) { |
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| 66 | 18 | $this->loadProxyClient($container, $loader, $config['proxy_client']); |
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| 67 | } |
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| 68 | |||
| 69 | 25 | if (isset($config['test'])) { |
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| 70 | 2 | $this->loadTest($container, $loader, $config['test']); |
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| 71 | } |
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| 72 | |||
| 73 | 25 | if ($config['cache_manager']['enabled']) { |
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| 74 | 18 | if (array_key_exists('custom_proxy_client', $config['cache_manager'])) { |
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| 75 | // overwrite the previously set alias, if a proxy client was also configured |
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| 76 | 1 | $container->setAlias( |
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| 77 | 1 | $this->getAlias().'.default_proxy_client', |
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| 78 | 1 | $config['cache_manager']['custom_proxy_client'] |
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| 79 | ); |
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| 80 | } |
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| 81 | 18 | if ('auto' === $config['cache_manager']['generate_url_type']) { |
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| 82 | 18 | if (array_key_exists('custom_proxy_client', $config['cache_manager'])) { |
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| 83 | 1 | $generateUrlType = UrlGeneratorInterface::ABSOLUTE_URL; |
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| 84 | } else { |
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| 85 | 17 | $defaultClient = $this->getDefaultProxyClient($config['proxy_client']); |
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| 86 | 17 | if ('noop' !== $defaultClient |
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| 87 | 17 | && array_key_exists('base_url', $config['proxy_client'][$defaultClient])) { |
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| 88 | $generateUrlType = UrlGeneratorInterface::ABSOLUTE_PATH; |
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| 89 | } else { |
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| 90 | 18 | $generateUrlType = UrlGeneratorInterface::ABSOLUTE_URL; |
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| 91 | } |
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| 92 | } |
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| 93 | } else { |
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| 94 | $generateUrlType = $config['cache_manager']['generate_url_type']; |
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| 95 | } |
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| 96 | 18 | $container->setParameter($this->getAlias().'.cache_manager.generate_url_type', $generateUrlType); |
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| 97 | 18 | $loader->load('cache_manager.xml'); |
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| 98 | 18 | if (class_exists(Application::class)) { |
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| 99 | 18 | $loader->load('cache_manager_commands.xml'); |
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| 100 | } |
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| 101 | } |
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| 102 | |||
| 103 | 25 | if ($config['tags']['enabled']) { |
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| 104 | 18 | $this->loadCacheTagging( |
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| 105 | 18 | $container, |
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| 106 | 18 | $loader, |
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| 107 | 18 | $config['tags'], |
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| 108 | 18 | array_key_exists('proxy_client', $config) |
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| 109 | 17 | ? $this->getDefaultProxyClient($config['proxy_client']) |
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| 110 | 18 | : 'custom' |
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| 111 | ); |
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| 112 | } else { |
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| 113 | 7 | $container->setParameter($this->getAlias().'.compiler_pass.tag_annotations', false); |
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| 114 | } |
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| 115 | |||
| 116 | 24 | if ($config['invalidation']['enabled']) { |
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| 117 | 17 | $loader->load('invalidation_listener.xml'); |
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| 118 | |||
| 119 | 17 | if (!empty($config['invalidation']['expression_language'])) { |
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| 120 | $container->setAlias( |
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| 121 | $this->getAlias().'.invalidation.expression_language', |
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| 122 | $config['invalidation']['expression_language'] |
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| 123 | ); |
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| 124 | } |
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| 125 | |||
| 126 | 17 | if (!empty($config['invalidation']['rules'])) { |
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| 127 | 3 | $this->loadInvalidatorRules($container, $config['invalidation']['rules']); |
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| 128 | } |
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| 129 | } |
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| 130 | |||
| 131 | 24 | if ($config['user_context']['enabled']) { |
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| 132 | 5 | $this->loadUserContext($container, $loader, $config['user_context']); |
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| 133 | } |
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| 134 | |||
| 135 | 24 | if (!empty($config['flash_message']) && $config['flash_message']['enabled']) { |
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| 136 | 3 | unset($config['flash_message']['enabled']); |
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| 137 | 3 | $container->setParameter($this->getAlias().'.event_listener.flash_message.options', $config['flash_message']); |
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| 138 | |||
| 139 | 3 | $loader->load('flash_message.xml'); |
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| 140 | } |
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| 141 | 24 | } |
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| 142 | |||
| 143 | 27 | private function loadCacheable(ContainerBuilder $container, array $config) |
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| 144 | { |
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| 145 | 27 | $definition = $container->getDefinition($this->getAlias().'.response_matcher.cacheable'); |
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| 146 | |||
| 147 | // Change CacheableResponseMatcher to ExpressionResponseMatcher |
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| 148 | 27 | if ($config['response']['expression']) { |
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| 149 | $definition->setClass(ExpressionResponseMatcher::class) |
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| 150 | ->setArguments([$config['response']['expression']]); |
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| 151 | } else { |
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| 152 | 27 | $container->setParameter( |
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| 153 | 27 | $this->getAlias().'.cacheable.response.additional_status', |
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| 154 | 27 | $config['response']['additional_status'] |
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| 155 | ); |
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| 156 | } |
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| 157 | 27 | } |
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| 158 | |||
| 159 | /** |
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| 160 | * @param ContainerBuilder $container |
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| 161 | * @param array $config |
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| 162 | * |
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| 163 | * @throws InvalidConfigurationException |
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| 164 | */ |
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| 165 | 7 | private function loadCacheControl(ContainerBuilder $container, array $config) |
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| 166 | { |
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| 167 | 7 | $controlDefinition = $container->getDefinition($this->getAlias().'.event_listener.cache_control'); |
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| 168 | |||
| 169 | 7 | foreach ($config['rules'] as $rule) { |
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| 170 | 7 | $ruleMatcher = $this->parseRuleMatcher($container, $rule['match']); |
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| 171 | |||
| 172 | 7 | if ('default' === $rule['headers']['overwrite']) { |
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| 173 | 7 | $rule['headers']['overwrite'] = $config['defaults']['overwrite']; |
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| 174 | } |
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| 175 | |||
| 176 | 7 | $controlDefinition->addMethodCall('addRule', [$ruleMatcher, $rule['headers']]); |
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| 177 | } |
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| 178 | 6 | } |
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| 179 | |||
| 180 | /** |
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| 181 | * Parse one cache control rule match configuration. |
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| 182 | * |
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| 183 | * @param ContainerBuilder $container |
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| 184 | * @param array $match Request and response match criteria |
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| 185 | * |
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| 186 | * @return Reference pointing to a rule matcher service |
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| 187 | */ |
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| 188 | 7 | private function parseRuleMatcher(ContainerBuilder $container, array $match) |
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| 189 | { |
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| 190 | 7 | $requestMatcher = $this->parseRequestMatcher($container, $match); |
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| 191 | 7 | $responseMatcher = $this->parseResponseMatcher($container, $match); |
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| 192 | |||
| 193 | 7 | $signature = serialize([(string) $requestMatcher, (string) $responseMatcher]); |
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| 194 | 7 | $id = $this->getAlias().'.cache_control.rule_matcher.'.md5($signature); |
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| 195 | |||
| 196 | 7 | if ($container->hasDefinition($id)) { |
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| 197 | 1 | throw new InvalidConfigurationException('Duplicate match criteria. Would be hidden by a previous rule. match: '.json_encode($match)); |
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| 198 | } |
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| 199 | |||
| 200 | $container |
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| 201 | 7 | ->setDefinition($id, $this->createChildDefinition($this->getAlias().'.rule_matcher')) |
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| 202 | 7 | ->replaceArgument(0, $requestMatcher) |
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| 203 | 7 | ->replaceArgument(1, $responseMatcher) |
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| 204 | ; |
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| 205 | |||
| 206 | 7 | return new Reference($id); |
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| 207 | } |
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| 208 | |||
| 209 | /** |
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| 210 | * Used for cache control, tag and invalidation rules. |
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| 211 | * |
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| 212 | * @param ContainerBuilder $container |
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| 213 | * @param array $match |
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| 214 | * |
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| 215 | * @return Reference to the request matcher |
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| 216 | */ |
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| 217 | 9 | private function parseRequestMatcher(ContainerBuilder $container, array $match) |
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| 218 | { |
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| 219 | 9 | $match['ips'] = (empty($match['ips'])) ? null : $match['ips']; |
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| 220 | |||
| 221 | $arguments = [ |
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| 222 | 9 | $match['path'], |
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| 223 | 9 | $match['host'], |
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| 224 | 9 | $match['methods'], |
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| 225 | 9 | $match['ips'], |
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| 226 | 9 | $match['attributes'], |
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| 227 | ]; |
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| 228 | 9 | $serialized = serialize($arguments); |
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| 229 | 9 | $id = $this->getAlias().'.request_matcher.'.md5($serialized).sha1($serialized); |
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| 230 | |||
| 231 | 9 | if (!$container->hasDefinition($id)) { |
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| 232 | $container |
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| 233 | 9 | ->setDefinition($id, $this->createChildDefinition($this->getAlias().'.request_matcher')) |
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| 234 | 9 | ->setArguments($arguments) |
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| 235 | ; |
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| 236 | |||
| 237 | 9 | if (!empty($match['query_string'])) { |
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| 238 | $container->getDefinition($id)->addMethodCall('setQueryString', [$match['query_string']]); |
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| 239 | } |
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| 240 | } |
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| 241 | |||
| 242 | 9 | return new Reference($id); |
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| 243 | } |
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| 244 | |||
| 245 | /** |
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| 246 | * Used only for cache control rules. |
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| 247 | * |
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| 248 | * @param ContainerBuilder $container |
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| 249 | * @param array $config |
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| 250 | * |
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| 251 | * @return Reference to the correct response matcher service |
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| 252 | */ |
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| 253 | 7 | private function parseResponseMatcher(ContainerBuilder $container, array $config) |
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| 254 | { |
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| 255 | 7 | if (!empty($config['additional_response_status'])) { |
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| 256 | 1 | $id = $this->getAlias().'cache_control.expression.'.md5(serialize($config['additional_response_status'])); |
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| 257 | 1 | View Code Duplication | if (!$container->hasDefinition($id)) { |
| 258 | $container |
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| 259 | 1 | ->setDefinition($id, $this->createChildDefinition($this->getAlias().'.response_matcher.cache_control.cacheable_response')) |
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| 260 | 1 | ->setArguments([$config['additional_response_status']]) |
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| 261 | ; |
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| 262 | } |
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| 263 | 6 | } elseif (!empty($config['match_response'])) { |
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| 264 | 2 | $id = $this->getAlias().'cache_control.match_response.'.md5($config['match_response']); |
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| 265 | 2 | View Code Duplication | if (!$container->hasDefinition($id)) { |
| 266 | $container |
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| 267 | 2 | ->setDefinition($id, $this->createChildDefinition($this->getAlias().'.response_matcher.cache_control.expression')) |
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| 268 | 2 | ->replaceArgument(0, $config['match_response']) |
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| 269 | ; |
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| 270 | } |
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| 271 | } else { |
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| 272 | 4 | $id = $this->getAlias().'.response_matcher.cacheable'; |
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| 273 | } |
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| 274 | |||
| 275 | 7 | return new Reference($id); |
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| 276 | } |
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| 277 | |||
| 278 | 5 | private function loadUserContext(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 279 | { |
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| 280 | 5 | $loader->load('user_context.xml'); |
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| 281 | |||
| 282 | 5 | $container->getDefinition($this->getAlias().'.user_context.request_matcher') |
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| 283 | 5 | ->replaceArgument(0, $config['match']['accept']) |
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| 284 | 5 | ->replaceArgument(1, $config['match']['method']); |
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| 285 | |||
| 286 | 5 | $container->setParameter($this->getAlias().'.event_listener.user_context.options', [ |
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| 287 | 5 | 'user_identifier_headers' => $config['user_identifier_headers'], |
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| 288 | 5 | 'user_hash_header' => $config['user_hash_header'], |
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| 289 | 5 | 'ttl' => $config['hash_cache_ttl'], |
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| 290 | 5 | 'add_vary_on_hash' => $config['always_vary_on_context_hash'], |
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| 291 | ]); |
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| 292 | 5 | $container->getDefinition($this->getAlias().'.event_listener.user_context') |
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| 293 | 5 | ->replaceArgument(0, new Reference($config['match']['matcher_service'])); |
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| 294 | |||
| 295 | 5 | $container->getDefinition($this->getAlias().'.user_context.anonymous_request_matcher') |
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| 296 | 5 | ->replaceArgument(0, $config['user_identifier_headers']); |
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| 297 | |||
| 298 | 5 | if ($config['logout_handler']['enabled']) { |
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| 299 | 5 | $container->getDefinition($this->getAlias().'.user_context_invalidator') |
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| 300 | 5 | ->replaceArgument(1, $config['user_identifier_headers']) |
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| 301 | 5 | ->replaceArgument(2, $config['match']['accept']); |
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| 302 | |||
| 303 | 5 | $container->setAlias('security.logout.handler.session', $this->getAlias().'.user_context.session_logout_handler'); |
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| 304 | } else { |
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| 305 | $container->removeDefinition($this->getAlias().'.user_context.logout_handler'); |
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| 306 | $container->removeDefinition($this->getAlias().'.user_context.session_logout_handler'); |
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| 307 | $container->removeDefinition($this->getAlias().'.user_context_invalidator'); |
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| 308 | } |
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| 309 | |||
| 310 | 5 | if ($config['role_provider']) { |
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| 311 | 3 | $container->getDefinition($this->getAlias().'.user_context.role_provider') |
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| 312 | 3 | ->addTag(HashGeneratorPass::TAG_NAME) |
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| 313 | 3 | ->setAbstract(false); |
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| 314 | } |
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| 315 | 5 | } |
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| 316 | |||
| 317 | 18 | private function loadProxyClient(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 337 | |||
| 338 | /** |
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| 339 | * Define the http dispatcher service for the proxy client $name. |
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| 340 | * |
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| 341 | * @param ContainerBuilder $container |
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| 342 | * @param array $config |
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| 343 | * @param string $serviceName |
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| 344 | */ |
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| 345 | 17 | private function createHttpDispatcherDefinition(ContainerBuilder $container, array $config, $serviceName) |
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| 369 | |||
| 370 | 14 | private function loadVarnish(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 386 | |||
| 387 | 2 | private function loadNginx(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 395 | |||
| 396 | 1 | private function loadSymfony(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 397 | { |
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| 398 | 1 | $this->createHttpDispatcherDefinition($container, $config['http'], $this->getAlias().'.proxy_client.symfony.http_dispatcher'); |
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| 399 | $options = [ |
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| 400 | 1 | 'tags_header' => $config['tags_header'], |
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| 401 | 1 | 'tags_method' => $config['tags_method'], |
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| 402 | 1 | 'purge_method' => $config['purge_method'], |
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| 403 | ]; |
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| 404 | 1 | if (!empty($config['header_length'])) { |
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| 405 | $options['header_length'] = $config['header_length']; |
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| 406 | } |
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| 407 | 1 | $container->setParameter($this->getAlias().'.proxy_client.symfony.options', $options); |
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| 408 | |||
| 409 | 1 | $loader->load('symfony.xml'); |
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| 410 | 1 | } |
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| 411 | |||
| 412 | /** |
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| 413 | * @param ContainerBuilder $container |
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| 414 | * @param XmlFileLoader $loader |
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| 415 | * @param array $config Configuration section for the tags node |
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| 416 | * @param string $client Name of the client used with the cache manager, |
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| 417 | * "custom" when a custom client is used |
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| 418 | */ |
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| 419 | 18 | private function loadCacheTagging(ContainerBuilder $container, XmlFileLoader $loader, array $config, $client) |
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| 420 | { |
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| 421 | 18 | if ('auto' === $config['enabled'] && !in_array($client, ['varnish', 'symfony'])) { |
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| 422 | 3 | $container->setParameter($this->getAlias().'.compiler_pass.tag_annotations', false); |
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| 423 | |||
| 424 | 3 | return; |
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| 425 | } |
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| 426 | 15 | if (!in_array($client, ['varnish', 'symfony', 'custom', 'noop'])) { |
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| 427 | 1 | throw new InvalidConfigurationException(sprintf('You can not enable cache tagging with the %s client', $client)); |
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| 428 | } |
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| 429 | |||
| 430 | 14 | $container->setParameter($this->getAlias().'.compiler_pass.tag_annotations', true); |
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| 431 | 14 | $container->setParameter($this->getAlias().'.tag_handler.response_header', $config['response_header']); |
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| 432 | 14 | $container->setParameter($this->getAlias().'.tag_handler.strict', $config['strict']); |
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| 433 | 14 | $loader->load('cache_tagging.xml'); |
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| 434 | 14 | if (class_exists(Application::class)) { |
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| 435 | 14 | $loader->load('cache_tagging_commands.xml'); |
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| 436 | } |
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| 437 | |||
| 438 | 14 | if (!empty($config['expression_language'])) { |
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| 439 | $container->setAlias( |
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| 440 | $this->getAlias().'.tag_handler.expression_language', |
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| 441 | $config['expression_language'] |
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| 442 | ); |
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| 443 | } |
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| 444 | |||
| 445 | 14 | if (!empty($config['rules'])) { |
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| 446 | 3 | $this->loadTagRules($container, $config['rules']); |
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| 447 | } |
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| 448 | 14 | } |
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| 449 | |||
| 450 | 2 | private function loadTest(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 451 | { |
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| 452 | 2 | $container->setParameter($this->getAlias().'.test.cache_header', $config['cache_header']); |
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| 453 | |||
| 454 | 2 | if ($config['proxy_server']) { |
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| 455 | 2 | $this->loadProxyServer($container, $loader, $config['proxy_server']); |
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| 456 | } |
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| 457 | 2 | } |
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| 458 | |||
| 459 | 2 | private function loadProxyServer(ContainerBuilder $container, XmlFileLoader $loader, array $config) |
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| 460 | { |
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| 461 | 2 | if (isset($config['varnish'])) { |
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| 462 | 2 | $this->loadVarnishProxyServer($container, $loader, $config['varnish']); |
|
| 463 | } |
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| 464 | |||
| 465 | 2 | if (isset($config['nginx'])) { |
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| 466 | $this->loadNginxProxyServer($container, $loader, $config['nginx']); |
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| 467 | } |
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| 468 | |||
| 469 | 2 | $container->setAlias( |
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| 470 | 2 | $this->getAlias().'.test.default_proxy_server', |
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| 471 | 2 | $this->getAlias().'.test.proxy_server.'.$this->getDefaultProxyClient($config) |
|
| 472 | ); |
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| 473 | 2 | } |
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| 474 | |||
| 475 | 2 | private function loadVarnishProxyServer(ContainerBuilder $container, XmlFileLoader $loader, $config) |
|
| 476 | { |
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| 477 | 2 | $loader->load('varnish_proxy.xml'); |
|
| 478 | 2 | foreach ($config as $key => $value) { |
|
| 479 | 2 | $container->setParameter( |
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| 480 | 2 | $this->getAlias().'.test.proxy_server.varnish.'.$key, |
|
| 481 | 2 | $value |
|
| 482 | ); |
||
| 483 | } |
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| 484 | 2 | } |
|
| 485 | |||
| 486 | private function loadNginxProxyServer(ContainerBuilder $container, XmlFileLoader $loader, $config) |
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| 487 | { |
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| 488 | $loader->load('nginx_proxy.xml'); |
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| 489 | foreach ($config as $key => $value) { |
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| 490 | $container->setParameter( |
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| 491 | $this->getAlias().'.test.proxy_server.nginx.'.$key, |
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| 492 | $value |
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| 493 | ); |
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| 494 | } |
||
| 495 | } |
||
| 496 | |||
| 497 | 3 | private function loadTagRules(ContainerBuilder $container, array $config) |
|
| 512 | |||
| 513 | 3 | private function loadInvalidatorRules(ContainerBuilder $container, array $config) |
|
| 514 | { |
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| 515 | 3 | $tagDefinition = $container->getDefinition($this->getAlias().'.event_listener.invalidation'); |
|
| 516 | |||
| 517 | 3 | foreach ($config as $rule) { |
|
| 518 | 3 | $ruleMatcher = $this->parseRequestMatcher($container, $rule['match']); |
|
| 519 | 3 | $tagDefinition->addMethodCall('addRule', [$ruleMatcher, $rule['routes']]); |
|
| 520 | } |
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| 521 | 3 | } |
|
| 522 | |||
| 523 | 17 | private function validateUrl($url, $msg) |
|
| 524 | { |
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| 525 | 17 | $prefixed = $this->prefixSchema($url); |
|
| 531 | |||
| 532 | 17 | private function prefixSchema($url) |
|
| 540 | |||
| 541 | 17 | private function getDefaultProxyClient(array $config) |
|
| 565 | |||
| 566 | /** |
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| 567 | * Build the child definition with fallback for Symfony versions < 3.3. |
||
| 568 | * |
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| 569 | * @param string $id Id of the service to extend |
||
| 570 | * |
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| 571 | * @return ChildDefinition|DefinitionDecorator |
||
| 572 | */ |
||
| 573 | 9 | private function createChildDefinition($id) |
|
| 581 | } |
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| 582 |
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Unless you are absolutely sure that the expression can never be null because of other conditions, we strongly recommend to add an additional type check to your code: