SchemaLoader::extractCacheMetadata() - Code Metrics - Inspection of "Implement query reducers." - drupal-graphql/graphql - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Pull Request — 8.x-3.x (#519)

by Sebastian

created 2018-02-14 17:59 UTC

SchemaLoader::extractCacheMetadata() B

↳ Parent: SchemaLoader

Complexity

Conditions	8
Paths	9

Size

Total Lines	20
Code Lines	11

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	8
eloc	11
nc	9
nop	1
dl	0
loc	20
rs	7.7777
c	0
b	0
f	0

<?php

namespace Drupal\graphql\GraphQL\Schema;

use Drupal\graphql\GraphQL\CacheableEdgeInterface;
use Drupal\graphql\GraphQL\Utility\TypeCollector;
use Drupal\Core\Cache\Cache;
use Drupal\Core\Cache\CacheableDependencyInterface;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Cache\CacheBackendInterface;
use Drupal\Core\Cache\Context\CacheContextsManager;
use Drupal\graphql\Plugin\GraphQL\SchemaPluginManager;
use Symfony\Component\HttpFoundation\RequestStack;
use Youshido\GraphQL\Schema\AbstractSchema;
use Youshido\GraphQL\Type\InputObject\AbstractInputObjectType;
use Youshido\GraphQL\Type\InterfaceType\AbstractInterfaceType;
use Youshido\GraphQL\Type\Object\AbstractObjectType;

/**
 * Loads and caches a generated GraphQL schema.
 */
class SchemaLoader {

  /**
   * The cache contexts manager service.
   *
   * @var \Drupal\Core\Cache\Context\CacheContextsManager
   */
  protected $contextsManager;

  /**
   * The schema plugin manager service.
   *
   * @var \Drupal\graphql\Plugin\GraphQL\SchemaPluginManager
   */
  protected $schemaManager;

  /**
   * The schema cache backend.
   *
   * @var \Drupal\Core\Cache\CacheBackendInterface
   */
  protected $schemaCache;

  /**
   * The cache metadata cache.
   *
   * @var \Drupal\Core\Cache\CacheBackendInterface
   */
  protected $metadataCache;

  /**
   * The service configuration.
   *
   * @var array
   */
  protected $config;

  /**
   * The request stack service.
   *
   * @var \Symfony\Component\HttpFoundation\RequestStack
   */
  protected $requestStack;

  /**
   * Static cache of loaded schemas.
   *
   * @var \Youshido\GraphQL\Schema\AbstractSchema[]
   */
  protected $schemas = [];

  /**
   * Static cache of loaded cache metadata.
   *
   * @var \Drupal\Core\Cache\RefinableCacheableDependencyInterface[]
   */
  protected $metadata = [];

  /**
   * SchemaLoader constructor.
   *
   * @param \Drupal\Core\Cache\Context\CacheContextsManager $contextsManager
   *   The cache contexts manager service.
   * @param \Symfony\Component\HttpFoundation\RequestStack $requestStack
   *   The request stack service.
   * @param \Drupal\graphql\Plugin\GraphQL\SchemaPluginManager $schemaManager
   *   The schema plugin manager service.
   * @param \Drupal\Core\Cache\CacheBackendInterface $schemaCache
   *   The schema cache backend.
   * @param \Drupal\Core\Cache\CacheBackendInterface $metadataCache
   *   The metadata cache backend.
   * @param array $config
   *   The configuration provided through the services.yml.
   */
  public function __construct(
    CacheContextsManager $contextsManager,
    RequestStack $requestStack,
    SchemaPluginManager $schemaManager,
    CacheBackendInterface $schemaCache,
    CacheBackendInterface $metadataCache,
    array $config
  ) {
    $this->config = $config;
    $this->schemaManager = $schemaManager;
    $this->contextsManager = $contextsManager;
    $this->schemaCache = $schemaCache;
    $this->metadataCache = $metadataCache;
    $this->requestStack = $requestStack;
  }

  /**
   * Loads and caches the generated schema.
   *
   * @param string $name
   *   The name of the schema to load.
   *
   * @return \Youshido\GraphQL\Schema\AbstractSchema
   *   The generated GraphQL schema.
   */
  public function getSchema($name) {
    if (array_key_exists($name, $this->schemas)) {
      return $this->schemas[$name];
    }

    // The cache key is made up of all of the globally known cache contexts.
    if (!empty($this->config['schema_cache'])) {
      if (($contextCache = $this->metadataCache->get($name)) && $contextCache->data) {
        $cid = $this->getCacheIdentifier($name, $contextCache->data);

        if (($schema = $this->schemaCache->get($cid)) && $schema->data) {
          return $this->schemas[$name] = $schema->data;
        }
      }
    }

    $this->schemas[$name] = $this->schemaManager->createInstance($name)->getSchema();
    // If the schema is not cacheable, just return it directly.
    if (empty($this->config['schema_cache'])) {
      return $this->schemas[$name];
    }

    // Compute the cache identifier, tag and expiry time.
    $schemaCacheMetadata = $this->getCacheMetadata($name);
    if ($schemaCacheMetadata->getCacheMaxAge() !== 0) {
      $tags = $schemaCacheMetadata->getCacheTags();
      $expire = $this->maxAgeToExpire($schemaCacheMetadata->getCacheMaxAge());
      $cid = $this->getCacheIdentifier($name, $schemaCacheMetadata);

      // Write the cache entry for the schema cache entries.
      $this->schemaCache->set($cid, $this->schemas[$name], $expire, $tags);
    }

    return $this->schemas[$name];
  }

  /**
   * Retrieves the schema's cache metadata.
   *
   * @param string $name
   *   The name of the schema.
   * @return \Drupal\Core\Cache\CacheableDependencyInterface
   *   The cache metadata for the schema.
   */
  public function getCacheMetadata($name) {
    if (array_key_exists($name, $this->metadata)) {
      return $this->metadata[$name];
class Author {
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function getName() {
        return $this->name;
    }
}

abstract class Post {
    public function getAuthor() {
        return 'Johannes';
    }
}

class BlogPost extends Post {
    public function getAuthor() {
        return new Author('Johannes');
    }
}

class ForumPost extends Post { /* ... */ }

function my_function(Post $post) {
    echo strtoupper($post->getAuthor());
}
    }

    // The cache key is made up of all of the globally known cache contexts.
    if (!empty($this->config['schema_cache'])) {
      if (($metadataCache = $this->metadataCache->get($name)) && $metadataCache->data) {
        return $this->metadata[$name] = $metadataCache->data;
      }
    }

    /** @var \Drupal\Core\Cache\RefinableCacheableDependencyInterface $metadata */
    $schema = $this->getSchema($name);
    $metadata = $this->extractCacheMetadata($schema);
    $this->metadata[$name] = $metadata;
    if (empty($this->config['schema_cache'])) {
      return $this->metadata[$name];
class Author {
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function getName() {
        return $this->name;
    }
}

abstract class Post {
    public function getAuthor() {
        return 'Johannes';
    }
}

class BlogPost extends Post {
    public function getAuthor() {
        return new Author('Johannes');
    }
}

class ForumPost extends Post { /* ... */ }

function my_function(Post $post) {
    echo strtoupper($post->getAuthor());
}
    }

    if (($maxAge = $metadata->getCacheMaxAge()) !== 0) {
      $tags = $metadata->getCacheTags();
      $expire = $this->maxAgeToExpire($maxAge);

      // Write the cache entry for the schema cache metadata.
      $this->metadataCache->set($name, $metadata, $expire, $tags);
    }

    return $metadata;
class Author {
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function getName() {
        return $this->name;
    }
}

abstract class Post {
    public function getAuthor() {
        return 'Johannes';
    }
}

class BlogPost extends Post {
    public function getAuthor() {
        return new Author('Johannes');
    }
}

class ForumPost extends Post { /* ... */ }

function my_function(Post $post) {
    echo strtoupper($post->getAuthor());
}
  }

  /**
   * Collects schema cache metadata from all types registered with the schema.
   *
   * The cache metadata is statically cached. This means that the schema may not
   * be modified after this method has been called.
   *
   * @param \Youshido\GraphQL\Schema\AbstractSchema $schema
   *   The schema to extract the cache metadata from.
   *
   * @return \Drupal\Core\Cache\CacheableMetadata
   *   The cache metadata collected from the schema's types.
   */
  protected function extractCacheMetadata(AbstractSchema $schema) {
    $metadata = new CacheableMetadata();
    $metadata->addCacheTags(['graphql_schema']);

    foreach (TypeCollector::collectTypes($schema) as $type) {
      if ($type instanceof CacheableEdgeInterface) {
        $metadata->addCacheableDependency($type->getSchemaCacheMetadata());
      }

      if ($type instanceof AbstractObjectType || $type instanceof AbstractInputObjectType || $type instanceof AbstractInterfaceType) {
        foreach ($type->getFields() as $field) {
          if ($field instanceof CacheableEdgeInterface) {
            $metadata->addCacheableDependency($field->getSchemaCacheMetadata());
          }
        }
      }
    }

    return $metadata;
  }

  /**
   * Maps a max age value to an "expire" value for the Cache API.
   *
   * @param int $maxAge
   *   A max age value.
   *
   * @return int
   *   A corresponding "expire" value.
   *
   * @see \Drupal\Core\Cache\CacheBackendInterface::set()
   */
  protected function maxAgeToExpire($maxAge) {

    if ($maxAge === Cache::PERMANENT) {
      return Cache::PERMANENT;
    }

    return (int) $this->requestStack->getMasterRequest()->server->get('REQUEST_TIME') + $maxAge;
  }

  /**
   * Generates a cache identifier for the passed cache contexts.
   *
   * @param string $name
   *   The name of the schema.
   * @param \Drupal\Core\Cache\CacheableDependencyInterface $metadata
   *   Optional array of cache context tokens.
   *
   * @return string The generated cache identifier.
   *   The generated cache identifier.
   */
  protected function getCacheIdentifier($name, CacheableDependencyInterface $metadata) {
    $tokens = $metadata->getCacheContexts();
    $keys = $this->contextsManager->convertTokensToKeys($tokens)->getKeys();
    return implode(':', array_merge(['graphql', $name], array_values($keys)));
  }

}


1		<?php
2
3		namespace Drupal\graphql\GraphQL\Schema;
4
5		use Drupal\graphql\GraphQL\CacheableEdgeInterface;
6		use Drupal\graphql\GraphQL\Utility\TypeCollector;
7		use Drupal\Core\Cache\Cache;
8		use Drupal\Core\Cache\CacheableDependencyInterface;
9		use Drupal\Core\Cache\CacheableMetadata;
10		use Drupal\Core\Cache\CacheBackendInterface;
11		use Drupal\Core\Cache\Context\CacheContextsManager;
12		use Drupal\graphql\Plugin\GraphQL\SchemaPluginManager;
13		use Symfony\Component\HttpFoundation\RequestStack;
14		use Youshido\GraphQL\Schema\AbstractSchema;
15		use Youshido\GraphQL\Type\InputObject\AbstractInputObjectType;
16		use Youshido\GraphQL\Type\InterfaceType\AbstractInterfaceType;
17		use Youshido\GraphQL\Type\Object\AbstractObjectType;
18
19		/**
20		* Loads and caches a generated GraphQL schema.
21		*/
22		class SchemaLoader {
23
24		/**
25		* The cache contexts manager service.
26		*
27		* @var \Drupal\Core\Cache\Context\CacheContextsManager
28		*/
29		protected $contextsManager;
30
31		/**
32		* The schema plugin manager service.
33		*
34		* @var \Drupal\graphql\Plugin\GraphQL\SchemaPluginManager
35		*/
36		protected $schemaManager;
37
38		/**
39		* The schema cache backend.
40		*
41		* @var \Drupal\Core\Cache\CacheBackendInterface
42		*/
43		protected $schemaCache;
44
45		/**
46		* The cache metadata cache.
47		*
48		* @var \Drupal\Core\Cache\CacheBackendInterface
49		*/
50		protected $metadataCache;
51
52		/**
53		* The service configuration.
54		*
55		* @var array
56		*/
57		protected $config;
58
59		/**
60		* The request stack service.
61		*
62		* @var \Symfony\Component\HttpFoundation\RequestStack
63		*/
64		protected $requestStack;
65
66		/**
67		* Static cache of loaded schemas.
68		*
69		* @var \Youshido\GraphQL\Schema\AbstractSchema[]
70		*/
71		protected $schemas = [];
72
73		/**
74		* Static cache of loaded cache metadata.
75		*
76		* @var \Drupal\Core\Cache\RefinableCacheableDependencyInterface[]
77		*/
78		protected $metadata = [];
79
80		/**
81		* SchemaLoader constructor.
82		*
83		* @param \Drupal\Core\Cache\Context\CacheContextsManager $contextsManager
84		* The cache contexts manager service.
85		* @param \Symfony\Component\HttpFoundation\RequestStack $requestStack
86		* The request stack service.
87		* @param \Drupal\graphql\Plugin\GraphQL\SchemaPluginManager $schemaManager
88		* The schema plugin manager service.
89		* @param \Drupal\Core\Cache\CacheBackendInterface $schemaCache
90		* The schema cache backend.
91		* @param \Drupal\Core\Cache\CacheBackendInterface $metadataCache
92		* The metadata cache backend.
93		* @param array $config
94		* The configuration provided through the services.yml.
95		*/
96		public function __construct(
97		CacheContextsManager $contextsManager,
98		RequestStack $requestStack,
99		SchemaPluginManager $schemaManager,
100		CacheBackendInterface $schemaCache,
101		CacheBackendInterface $metadataCache,
102		array $config
103		) {
104		$this->config = $config;
105		$this->schemaManager = $schemaManager;
106		$this->contextsManager = $contextsManager;
107		$this->schemaCache = $schemaCache;
108		$this->metadataCache = $metadataCache;
109		$this->requestStack = $requestStack;
110		}
111
112		/**
113		* Loads and caches the generated schema.
114		*
115		* @param string $name
116		* The name of the schema to load.
117		*
118		* @return \Youshido\GraphQL\Schema\AbstractSchema
119		* The generated GraphQL schema.
120		*/
121		public function getSchema($name) {
122		if (array_key_exists($name, $this->schemas)) {
123		return $this->schemas[$name];
124		}
125
126		// The cache key is made up of all of the globally known cache contexts.
127		if (!empty($this->config['schema_cache'])) {
128		if (($contextCache = $this->metadataCache->get($name)) && $contextCache->data) {
129		$cid = $this->getCacheIdentifier($name, $contextCache->data);
130
131		if (($schema = $this->schemaCache->get($cid)) && $schema->data) {
132		return $this->schemas[$name] = $schema->data;
133		}
134		}
135		}
136
137		$this->schemas[$name] = $this->schemaManager->createInstance($name)->getSchema();
138		// If the schema is not cacheable, just return it directly.
139		if (empty($this->config['schema_cache'])) {
140		return $this->schemas[$name];
141		}
142
143		// Compute the cache identifier, tag and expiry time.
144		$schemaCacheMetadata = $this->getCacheMetadata($name);
145		if ($schemaCacheMetadata->getCacheMaxAge() !== 0) {
146		$tags = $schemaCacheMetadata->getCacheTags();
147		$expire = $this->maxAgeToExpire($schemaCacheMetadata->getCacheMaxAge());
148		$cid = $this->getCacheIdentifier($name, $schemaCacheMetadata);
149
150		// Write the cache entry for the schema cache entries.
151		$this->schemaCache->set($cid, $this->schemas[$name], $expire, $tags);
152		}
153
154		return $this->schemas[$name];
155		}
156
157		/**
158		* Retrieves the schema's cache metadata.
159		*
160		* @param string $name
161		* The name of the schema.
162		* @return \Drupal\Core\Cache\CacheableDependencyInterface
163		* The cache metadata for the schema.
164		*/
165		public function getCacheMetadata($name) {
166		if (array_key_exists($name, $this->metadata)) {
167		return $this->metadata[$name];
		0 ignored issues – show Bug Best Practice introduced 2018-02-14 16:13 UTC by Report Bug Copy Issue Report The return type of `return $this->metadata[$name];` (`Drupal\Core\Cache\Refina...ableDependencyInterface`) is incompatible with the return type documented by `Drupal\graphql\GraphQL\S...oader::getCacheMetadata` of type `Drupal\Core\Cache\CacheableDependencyInterface`. If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design. Let’s take a look at an example: class Author { private $name; public function __construct($name) { $this->name = $name; } public function getName() { return $this->name; } } abstract class Post { public function getAuthor() { return 'Johannes'; } } class BlogPost extends Post { public function getAuthor() { return new Author('Johannes'); } } class ForumPost extends Post { /* ... */ } function my_function(Post $post) { echo strtoupper($post->getAuthor()); } Our function `my_function` expects a `Post` object, and outputs the author of the post. The base class `Post` returns a simple string and outputting a simple string will work just fine. However, the child class `BlogPost` which is a sub-type of `Post` instead decided to return an `object`, and is therefore violating the SOLID principles. If a `BlogPost` were passed to `my_function`, PHP would not complain, but ultimately fail when executing the `strtoupper` call in its body. Loading history...
168		}
169
170		// The cache key is made up of all of the globally known cache contexts.
171		if (!empty($this->config['schema_cache'])) {
172		if (($metadataCache = $this->metadataCache->get($name)) && $metadataCache->data) {
173		return $this->metadata[$name] = $metadataCache->data;
174		}
175		}
176
177		/** @var \Drupal\Core\Cache\RefinableCacheableDependencyInterface $metadata */
178		$schema = $this->getSchema($name);
179		$metadata = $this->extractCacheMetadata($schema);
180		$this->metadata[$name] = $metadata;
181		if (empty($this->config['schema_cache'])) {
182		return $this->metadata[$name];
		0 ignored issues – show Bug Best Practice introduced 2018-02-14 16:13 UTC by Report Bug Copy Issue Report The return type of `return $this->metadata[$name];` (`Drupal\Core\Cache\Refina...Cache\CacheableMetadata`) is incompatible with the return type documented by `Drupal\graphql\GraphQL\S...oader::getCacheMetadata` of type `Drupal\Core\Cache\CacheableDependencyInterface`. If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design. Let’s take a look at an example: class Author { private $name; public function __construct($name) { $this->name = $name; } public function getName() { return $this->name; } } abstract class Post { public function getAuthor() { return 'Johannes'; } } class BlogPost extends Post { public function getAuthor() { return new Author('Johannes'); } } class ForumPost extends Post { /* ... */ } function my_function(Post $post) { echo strtoupper($post->getAuthor()); } Our function `my_function` expects a `Post` object, and outputs the author of the post. The base class `Post` returns a simple string and outputting a simple string will work just fine. However, the child class `BlogPost` which is a sub-type of `Post` instead decided to return an `object`, and is therefore violating the SOLID principles. If a `BlogPost` were passed to `my_function`, PHP would not complain, but ultimately fail when executing the `strtoupper` call in its body. Loading history...
183		}
184
185		if (($maxAge = $metadata->getCacheMaxAge()) !== 0) {
186		$tags = $metadata->getCacheTags();
187		$expire = $this->maxAgeToExpire($maxAge);
188
189		// Write the cache entry for the schema cache metadata.
190		$this->metadataCache->set($name, $metadata, $expire, $tags);
191		}
192
193		return $metadata;
		0 ignored issues – show Bug Best Practice introduced 2018-02-14 16:13 UTC by Report Bug Copy Issue Report The return type of `return $metadata;` (`Drupal\Core\Cache\CacheableMetadata`) is incompatible with the return type documented by `Drupal\graphql\GraphQL\S...oader::getCacheMetadata` of type `Drupal\Core\Cache\CacheableDependencyInterface`. If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design. Let’s take a look at an example: class Author { private $name; public function __construct($name) { $this->name = $name; } public function getName() { return $this->name; } } abstract class Post { public function getAuthor() { return 'Johannes'; } } class BlogPost extends Post { public function getAuthor() { return new Author('Johannes'); } } class ForumPost extends Post { /* ... */ } function my_function(Post $post) { echo strtoupper($post->getAuthor()); } Our function `my_function` expects a `Post` object, and outputs the author of the post. The base class `Post` returns a simple string and outputting a simple string will work just fine. However, the child class `BlogPost` which is a sub-type of `Post` instead decided to return an `object`, and is therefore violating the SOLID principles. If a `BlogPost` were passed to `my_function`, PHP would not complain, but ultimately fail when executing the `strtoupper` call in its body. Loading history...
194		}
195
196		/**
197		* Collects schema cache metadata from all types registered with the schema.
198		*
199		* The cache metadata is statically cached. This means that the schema may not
200		* be modified after this method has been called.
201		*
202		* @param \Youshido\GraphQL\Schema\AbstractSchema $schema
203		* The schema to extract the cache metadata from.
204		*
205		* @return \Drupal\Core\Cache\CacheableMetadata
206		* The cache metadata collected from the schema's types.
207		*/
208		protected function extractCacheMetadata(AbstractSchema $schema) {
209		$metadata = new CacheableMetadata();
210		$metadata->addCacheTags(['graphql_schema']);
211
212		foreach (TypeCollector::collectTypes($schema) as $type) {
213		if ($type instanceof CacheableEdgeInterface) {
214		$metadata->addCacheableDependency($type->getSchemaCacheMetadata());
215		}
216
217		if ($type instanceof AbstractObjectType \|\| $type instanceof AbstractInputObjectType \|\| $type instanceof AbstractInterfaceType) {
218		foreach ($type->getFields() as $field) {
219		if ($field instanceof CacheableEdgeInterface) {
220		$metadata->addCacheableDependency($field->getSchemaCacheMetadata());
221		}
222		}
223		}
224		}
225
226		return $metadata;
227		}
228
229		/**
230		* Maps a max age value to an "expire" value for the Cache API.
231		*
232		* @param int $maxAge
233		* A max age value.
234		*
235		* @return int
236		* A corresponding "expire" value.
237		*
238		* @see \Drupal\Core\Cache\CacheBackendInterface::set()
239		*/
240	View Code Duplication	protected function maxAgeToExpire($maxAge) {
		0 ignored issues – show Duplication introduced 2018-02-14 16:13 UTC by Report Bug Copy Issue Report This method seems to be duplicated in your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
241		if ($maxAge === Cache::PERMANENT) {
242		return Cache::PERMANENT;
243		}
244
245		return (int) $this->requestStack->getMasterRequest()->server->get('REQUEST_TIME') + $maxAge;
246		}
247
248		/**
249		* Generates a cache identifier for the passed cache contexts.
250		*
251		* @param string $name
252		* The name of the schema.
253		* @param \Drupal\Core\Cache\CacheableDependencyInterface $metadata
254		* Optional array of cache context tokens.
255		*
256		* @return string The generated cache identifier.
257		* The generated cache identifier.
258		*/
259		protected function getCacheIdentifier($name, CacheableDependencyInterface $metadata) {
260		$tokens = $metadata->getCacheContexts();
261		$keys = $this->contextsManager->convertTokensToKeys($tokens)->getKeys();
262		return implode(':', array_merge(['graphql', $name], array_values($keys)));
263		}
264
265		}
266

drupal-graphql / graphql

Pull Request — 8.x-3.x (#519)

SchemaLoader::extractCacheMetadata() B

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like