EntityRetrievingClosestReferencedEntityIdLookup::getEntity() - Code Metrics - Inspection of "Introduce EntityRetrievingClosestReferencedEntityI..." - wmde/WikibaseDataModelServices - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Pull Request — master (#195)

by Marius

created 2018-04-14 13:58 UTC

getEntity() B

↳ Parent: EntityRetrievingClosestReferencedEntityIdLookup

Complexity

Conditions	4
Paths	4

Size

Total Lines	24
Code Lines	15

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
dl	0
loc	24
rs	8.6845
c	0
b	0
f	0
cc	4
eloc	15
nc	4
nop	4

<?php

namespace Wikibase\DataModel\Services\Lookup;

use Wikibase\DataModel\Entity\EntityId;
use Wikibase\DataModel\Entity\EntityIdValue;
use Wikibase\DataModel\Entity\PropertyId;
use Wikibase\DataModel\Services\Entity\EntityPrefetcher;
use Wikibase\DataModel\Snak\PropertyValueSnak;
use Wikibase\DataModel\Snak\Snak;
use Wikibase\DataModel\Statement\StatementListProvider;

/**
 * Service for getting the closest entity (out of a specified set),
 * from a given starting entity. The starting entity, and the target entities
 * are (potentially indirectly, via intermediate entities) linked by statements
 * with a given property ID, pointing from the starting entity to one of the
 * target entities.
 *
 * @since 3.10
 *
 * @license GPL-2.0-or-later
 * @author Marius Hoch
 */
class EntityRetrievingClosestReferencedEntityIdLookup implements ReferencedEntityIdLookup {

	/**
	 * @var EntityLookup
	 */
	private $entityLookup;

	/**
	 * @var EntityPrefetcher
	 */
	private $entityPrefetcher;

	/**
	 * @var int Maximum search depth: Maximum number of intermediate entities to search through.
	 */
	private $maxDepth;

	/**
	 * @var int Maximum number of entities to retrieve.
	 */
	private $maxEntityVisits;

	/**
	 * Map (entity id => true) of already visited entities.
	 *
	 * @var bool[]
	 */
	private $alreadyVisited = [];

	/**
	 * @param EntityLookup $entityLookup
	 * @param EntityPrefetcher $entityPrefetcher
	 * @param int $maxDepth Maximum search depth: Maximum number of intermediate entities to search through.
	 * @param int $maxEntityVisits Maximum number of entities to retrieve during a lookup.
	 */
	public function __construct(
		EntityLookup $entityLookup,
		EntityPrefetcher $entityPrefetcher,
		$maxDepth,
		$maxEntityVisits
	) {
		$this->entityLookup = $entityLookup;
		$this->entityPrefetcher = $entityPrefetcher;
		$this->maxDepth = $maxDepth;
		$this->maxEntityVisits = $maxEntityVisits;
	}

	/**
	 * Get the closest entity (out of $toIds), from a given entity. The starting entity, and
	 * the target entities are (potentially indirectly, via intermediate entities) linked by
	 * statements with the given property ID, pointing from the starting entity to one of the
	 * target entities.
	 *
	 * @since 3.10
	 *
	 * @param EntityId $fromId
	 * @param PropertyId $propertyId
	 * @param EntityId[] $toIds
	 *
	 * @return EntityId|null Returns null in case none of the target entities are referenced.
	 * @throws ReferencedEntityIdLookupException
	 */
	public function getReferencedEntityId( EntityId $fromId, PropertyId $propertyId, array $toIds ) {
		if ( !$toIds ) {

			return null;
		}

		$this->alreadyVisited = [];

		$steps = $this->maxDepth + 1; // Add one as checking $fromId already is a step
		$toVisit = [ $fromId ];

		while ( $steps-- ) {
			$this->entityPrefetcher->prefetch( $toVisit );
			$toVisitNext = [];

			foreach ( $toVisit as $curId ) {
				$result = $this->processEntityById( $curId, $fromId, $propertyId, $toIds, $toVisitNext );
class A
{
    function getObject()
    {
        return null;
    }

}

$a = new A();
$object = $a->getObject();
				if ( $result ) {
					return $result;
				}
			}
			// Remove already visitted entities
			$toVisit = array_unique(
				array_diff( $toVisitNext, array_keys( $this->alreadyVisited ) )
			);

			if ( !$toVisit ) {

				return null;
			}
		}

		// Exhausted the max. depth without finding anything.
		throw new MaxReferenceDepthExhaustedException(
			$fromId,
			$propertyId,
			$toIds,
			$this->maxDepth
		);
	}

	/**
	 * Find out whether an entity (directly) references one of the target ids.
	 *
	 * @param EntityId $id Id of the entity to process
	 * @param EntityId $fromId Id this lookup started from
	 * @param PropertyId $propertyId
	 * @param EntityId[] $toIds
	 * @param EntityId[] &$toVisit List of entities that still need to be checked
	 * @return EntityId|null Target id the entity refers to, null if none.
	 */
	private function processEntityById(
		EntityId $id,
		EntityId $fromId,
		PropertyId $propertyId,
		array $toIds,
		array &$toVisit
	) {
		$entity = $this->getEntity( $id, $fromId, $propertyId, $toIds );
		if ( !$entity ) {
			return null;
		}

		$mainSnaks = $this->getMainSnaks( $entity, $propertyId );

		foreach ( $mainSnaks as $mainSnak ) {
			$result = $this->processSnak( $mainSnak, $toVisit, $toIds );
class A
{
    function getObject()
    {
        return null;
    }

}

$a = new A();
$object = $a->getObject();
			if ( $result ) {
				return $result;
			}
		}

		return null;
	}

	/**
	 * @param EntityId $id Id of the entity to get
	 * @param EntityId $fromId Id this lookup started from
	 * @param PropertyId $propertyId
	 * @param EntityId[] $toIds
	 *
	 * @return StatementListProvider|null Null if not applicable.
	 */
	private function getEntity( EntityId $id, EntityId $fromId, PropertyId $propertyId, array $toIds ) {
		$this->alreadyVisited[$id->getSerialization()] = true;

		if ( count( $this->alreadyVisited ) > $this->maxEntityVisits ) {
			throw new MaxReferencedEntityVisitsExhaustedException(
				$fromId,
				$propertyId,
				$toIds,
				$this->maxEntityVisits
			);
		}

		try {
			$entity = $this->entityLookup->getEntity( $id );
		} catch ( EntityLookupException $ex ) {
			throw new ReferencedEntityIdLookupException( $fromId, $propertyId, $toIds, null, $ex );
		}

		if ( !( $entity instanceof StatementListProvider ) ) {
			return null;
		}

		return $entity;
	}

	/**
	 * Decide whether a single Snak is pointing to one of the target ids.
	 *
	 * @param Snak $snak
	 * @param EntityId[] &$toVisit List of entities that still need to be checked
	 * @param EntityId[] $toIds
	 * @return EntityId|null Target id the Snak refers to, null if none.
	 */
	private function processSnak( Snak $snak, array &$toVisit, array $toIds ) {
		if ( ! ( $snak instanceof PropertyValueSnak ) ) {
			return null;
		}
		$dataValue = $snak->getDataValue();
		if ( ! ( $dataValue instanceof EntityIdValue ) ) {
			return null;
		}

		$entityId = $dataValue->getEntityId();
		if ( in_array( $entityId, $toIds, false ) ) {
			return $entityId;
		}

		$toVisit[] = $entityId;

		return null;
	}

	/**
	 * @param StatementListProvider $statementListProvider
	 * @param PropertyId $propertyId
	 * @return Snak[]
	 */
	private function getMainSnaks(
		StatementListProvider $statementListProvider,
		PropertyId $propertyId
	) {
		return $statementListProvider
			->getStatements()
			->getByPropertyId( $propertyId )
			->getBestStatements()
			->getMainSnaks();
	}

}


1			<?php
2
3			namespace Wikibase\DataModel\Services\Lookup;
4
5			use Wikibase\DataModel\Entity\EntityId;
6			use Wikibase\DataModel\Entity\EntityIdValue;
7			use Wikibase\DataModel\Entity\PropertyId;
8			use Wikibase\DataModel\Services\Entity\EntityPrefetcher;
9			use Wikibase\DataModel\Snak\PropertyValueSnak;
10			use Wikibase\DataModel\Snak\Snak;
11			use Wikibase\DataModel\Statement\StatementListProvider;
12
13			/**
14			* Service for getting the closest entity (out of a specified set),
15			* from a given starting entity. The starting entity, and the target entities
16			* are (potentially indirectly, via intermediate entities) linked by statements
17			* with a given property ID, pointing from the starting entity to one of the
18			* target entities.
19			*
20			* @since 3.10
21			*
22			* @license GPL-2.0-or-later
23			* @author Marius Hoch
24			*/
25			class EntityRetrievingClosestReferencedEntityIdLookup implements ReferencedEntityIdLookup {
26
27			/**
28			* @var EntityLookup
29			*/
30			private $entityLookup;
31
32			/**
33			* @var EntityPrefetcher
34			*/
35			private $entityPrefetcher;
36
37			/**
38			* @var int Maximum search depth: Maximum number of intermediate entities to search through.
39			*/
40			private $maxDepth;
41
42			/**
43			* @var int Maximum number of entities to retrieve.
44			*/
45			private $maxEntityVisits;
46
47			/**
48			* Map (entity id => true) of already visited entities.
49			*
50			* @var bool[]
51			*/
52			private $alreadyVisited = [];
53
54			/**
55			* @param EntityLookup $entityLookup
56			* @param EntityPrefetcher $entityPrefetcher
57			* @param int $maxDepth Maximum search depth: Maximum number of intermediate entities to search through.
58			* @param int $maxEntityVisits Maximum number of entities to retrieve during a lookup.
59			*/
60			public function __construct(
61			EntityLookup $entityLookup,
62			EntityPrefetcher $entityPrefetcher,
63			$maxDepth,
64			$maxEntityVisits
65			) {
66			$this->entityLookup = $entityLookup;
67			$this->entityPrefetcher = $entityPrefetcher;
68			$this->maxDepth = $maxDepth;
69			$this->maxEntityVisits = $maxEntityVisits;
70			}
71
72			/**
73			* Get the closest entity (out of $toIds), from a given entity. The starting entity, and
74			* the target entities are (potentially indirectly, via intermediate entities) linked by
75			* statements with the given property ID, pointing from the starting entity to one of the
76			* target entities.
77			*
78			* @since 3.10
79			*
80			* @param EntityId $fromId
81			* @param PropertyId $propertyId
82			* @param EntityId[] $toIds
83			*
84			* @return EntityId\|null Returns null in case none of the target entities are referenced.
85			* @throws ReferencedEntityIdLookupException
86			*/
87			public function getReferencedEntityId( EntityId $fromId, PropertyId $propertyId, array $toIds ) {
88			if ( !$toIds ) {
			0 ignored issues – show Bug Best Practice introduced 2018-04-14 13:42 UTC by Report Bug Copy Issue Report The expression `$toIds` of type `Wikibase\DataModel\Entity\EntityId[]` is implicitly converted to a boolean; are you sure this is intended? If so, consider using `empty($expr)` instead to make it clear that you intend to check for an array without elements. This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent. Consider making the comparison explicit by using `empty(..)` or `! empty(...)` instead. Loading history...
89			return null;
90			}
91
92			$this->alreadyVisited = [];
93
94			$steps = $this->maxDepth + 1; // Add one as checking $fromId already is a step
95			$toVisit = [ $fromId ];
96
97			while ( $steps-- ) {
98			$this->entityPrefetcher->prefetch( $toVisit );
99			$toVisitNext = [];
100
101			foreach ( $toVisit as $curId ) {
102			$result = $this->processEntityById( $curId, $fromId, $propertyId, $toIds, $toVisitNext );
			0 ignored issues – show Bug introduced 2018-04-14 13:42 UTC by Report Bug Copy Issue Report Are you sure the assignment to `$result` is correct as `$this->processEntityById..., $toIds, $toVisitNext)` (which targets `Wikibase\DataModel\Servi...up::processEntityById()`) seems to always return null. This check looks for function or method calls that always return null and whose return value is assigned to a variable. class A { function getObject() { return null; } } $a = new A(); $object = $a->getObject(); The method `getObject()` can return nothing but null, so it makes no sense to assign that value to a variable. The reason is most likely that a function or method is imcomplete or has been reduced for debug purposes. Loading history...
103			if ( $result ) {
104			return $result;
105			}
106			}
107			// Remove already visitted entities
108			$toVisit = array_unique(
109			array_diff( $toVisitNext, array_keys( $this->alreadyVisited ) )
110			);
111
112			if ( !$toVisit ) {
			0 ignored issues – show Bug Best Practice introduced 2018-04-14 13:42 UTC by Report Bug Copy Issue Report The expression `$toVisit` of type `array` is implicitly converted to a boolean; are you sure this is intended? If so, consider using `empty($expr)` instead to make it clear that you intend to check for an array without elements. This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent. Consider making the comparison explicit by using `empty(..)` or `! empty(...)` instead. Loading history...
113			return null;
114			}
115			}
116
117			// Exhausted the max. depth without finding anything.
118			throw new MaxReferenceDepthExhaustedException(
119			$fromId,
120			$propertyId,
121			$toIds,
122			$this->maxDepth
123			);
124			}
125
126			/**
127			* Find out whether an entity (directly) references one of the target ids.
128			*
129			* @param EntityId $id Id of the entity to process
130			* @param EntityId $fromId Id this lookup started from
131			* @param PropertyId $propertyId
132			* @param EntityId[] $toIds
133			* @param EntityId[] &$toVisit List of entities that still need to be checked
134			* @return EntityId\|null Target id the entity refers to, null if none.
135			*/
136			private function processEntityById(
137			EntityId $id,
138			EntityId $fromId,
139			PropertyId $propertyId,
140			array $toIds,
141			array &$toVisit
142			) {
143			$entity = $this->getEntity( $id, $fromId, $propertyId, $toIds );
144			if ( !$entity ) {
145			return null;
146			}
147
148			$mainSnaks = $this->getMainSnaks( $entity, $propertyId );
149
150			foreach ( $mainSnaks as $mainSnak ) {
151			$result = $this->processSnak( $mainSnak, $toVisit, $toIds );
			0 ignored issues – show Bug introduced 2018-04-14 13:42 UTC by Report Bug Copy Issue Report Are you sure the assignment to `$result` is correct as `$this->processSnak($mainSnak, $toVisit, $toIds)` (which targets `Wikibase\DataModel\Servi...IdLookup::processSnak()`) seems to always return null. This check looks for function or method calls that always return null and whose return value is assigned to a variable. class A { function getObject() { return null; } } $a = new A(); $object = $a->getObject(); The method `getObject()` can return nothing but null, so it makes no sense to assign that value to a variable. The reason is most likely that a function or method is imcomplete or has been reduced for debug purposes. Loading history...
152			if ( $result ) {
153			return $result;
154			}
155			}
156
157			return null;
158			}
159
160			/**
161			* @param EntityId $id Id of the entity to get
162			* @param EntityId $fromId Id this lookup started from
163			* @param PropertyId $propertyId
164			* @param EntityId[] $toIds
165			*
166			* @return StatementListProvider\|null Null if not applicable.
167			*/
168			private function getEntity( EntityId $id, EntityId $fromId, PropertyId $propertyId, array $toIds ) {
169			$this->alreadyVisited[$id->getSerialization()] = true;
170
171			if ( count( $this->alreadyVisited ) > $this->maxEntityVisits ) {
172			throw new MaxReferencedEntityVisitsExhaustedException(
173			$fromId,
174			$propertyId,
175			$toIds,
176			$this->maxEntityVisits
177			);
178			}
179
180			try {
181			$entity = $this->entityLookup->getEntity( $id );
182			} catch ( EntityLookupException $ex ) {
183			throw new ReferencedEntityIdLookupException( $fromId, $propertyId, $toIds, null, $ex );
184			}
185
186			if ( !( $entity instanceof StatementListProvider ) ) {
187			return null;
188			}
189
190			return $entity;
191			}
192
193			/**
194			* Decide whether a single Snak is pointing to one of the target ids.
195			*
196			* @param Snak $snak
197			* @param EntityId[] &$toVisit List of entities that still need to be checked
198			* @param EntityId[] $toIds
199			* @return EntityId\|null Target id the Snak refers to, null if none.
200			*/
201			private function processSnak( Snak $snak, array &$toVisit, array $toIds ) {
202			if ( ! ( $snak instanceof PropertyValueSnak ) ) {
203			return null;
204			}
205			$dataValue = $snak->getDataValue();
206			if ( ! ( $dataValue instanceof EntityIdValue ) ) {
207			return null;
208			}
209
210			$entityId = $dataValue->getEntityId();
211			if ( in_array( $entityId, $toIds, false ) ) {
212			return $entityId;
213			}
214
215			$toVisit[] = $entityId;
216
217			return null;
218			}
219
220			/**
221			* @param StatementListProvider $statementListProvider
222			* @param PropertyId $propertyId
223			* @return Snak[]
224			*/
225			private function getMainSnaks(
226			StatementListProvider $statementListProvider,
227			PropertyId $propertyId
228			) {
229			return $statementListProvider
230			->getStatements()
231			->getByPropertyId( $propertyId )
232			->getBestStatements()
233			->getMainSnaks();
234			}
235
236			}
237

wmde / WikibaseDataModelServices

Pull Request — master (#195)

getEntity() B

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like