Code Coverage |
||||||||||
Classes and Traits |
Functions and Methods |
Lines |
||||||||
| Total | |
0.00% |
0 / 1 |
|
66.67% |
2 / 3 |
CRAP | |
90.32% |
28 / 31 |
| EntitySchema\DataAccess\SqlIdGenerator | |
0.00% |
0 / 1 |
|
66.67% |
2 / 3 |
7.04 | |
90.32% |
28 / 31 |
| __construct | |
100.00% |
1 / 1 |
1 | |
100.00% |
3 / 3 |
|||
| getNewId | |
100.00% |
1 / 1 |
1 | |
100.00% |
4 / 4 |
|||
| generateNewId | |
0.00% |
0 / 1 |
5.05 | |
87.50% |
21 / 24 |
|||
| <?php | |
| namespace EntitySchema\DataAccess; | |
| use RuntimeException; | |
| use EntitySchema\Domain\Storage\IdGenerator; | |
| use Wikimedia\Rdbms\IDatabase; | |
| use Wikimedia\Rdbms\ILoadBalancer; | |
| /** | |
| * Unique Id generator implemented using an SQL table. | |
| * The table needs to have the fields id_value | |
| * | |
| * @license GPL-2.0-or-later | |
| * based on | |
| * @see \Wikibase\SqlIdGenerator | |
| */ | |
| class SqlIdGenerator implements IdGenerator { | |
| /** @var ILoadBalancer */ | |
| private $loadBalancer; | |
| /** @var string */ | |
| private $tableName; | |
| /** | |
| * @param ILoadBalancer $loadBalancer | |
| * @param string $tableName | |
| */ | |
| public function __construct( ILoadBalancer $loadBalancer, $tableName ) { | |
| $this->loadBalancer = $loadBalancer; | |
| $this->tableName = $tableName; | |
| } | |
| /** | |
| * @return int | |
| * | |
| * @throws RuntimeException | |
| */ | |
| public function getNewId() { | |
| $database = $this->loadBalancer->getConnection( DB_MASTER ); | |
| $id = $this->generateNewId( $database ); | |
| $this->loadBalancer->reuseConnection( $database ); | |
| return $id; | |
| } | |
| /** | |
| * Generates and returns a new ID. | |
| * | |
| * @param IDatabase $database | |
| * @param bool $retry Retry once in case of e.g. race conditions. Defaults to true. | |
| * | |
| * @throws RuntimeException | |
| * @return int | |
| */ | |
| private function generateNewId( IDatabase $database, $retry = true ) { | |
| $database->startAtomic( __METHOD__ ); | |
| $currentId = $database->selectRow( | |
| $this->tableName, | |
| 'id_value', | |
| [], | |
| __METHOD__, | |
| [ 'FOR UPDATE' ] | |
| ); | |
| if ( is_object( $currentId ) ) { | |
| $id = $currentId->id_value + 1; | |
| $success = $database->update( | |
| $this->tableName, | |
| [ 'id_value' => $id ], | |
| [] | |
| ); | |
| } else { | |
| $id = 1; | |
| $success = $database->insert( | |
| $this->tableName, | |
| [ | |
| 'id_value' => $id, | |
| ] | |
| ); | |
| // Retry once, since a race condition on initial insert can cause one to fail. | |
| // Race condition is possible due to occurrence of phantom reads is possible | |
| // at non serializable transaction isolation level. | |
| if ( !$success && $retry ) { | |
| $id = $this->generateNewId( $database, false ); | |
| $success = true; | |
| } | |
| } | |
| $database->endAtomic( __METHOD__ ); | |
| if ( !$success ) { | |
| throw new RuntimeException( 'Could not generate a reliably unique ID.' ); | |
| } | |
| return $id; | |
| } | |
| } |