yii2

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<?php
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/**
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 * @link https://www.yiiframework.com/
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 * @copyright Copyright (c) 2008 Yii Software LLC
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 * @license https://www.yiiframework.com/license/
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 */
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namespace yii\mutex;
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use PDO;
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use yii\base\InvalidConfigException;
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/**
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 * OracleMutex implements mutex "lock" mechanism via Oracle locks.
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 *
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 * Application configuration example:
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 *
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 * ```
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 * [
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 *     'components' => [
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 *         'db' => [
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 *             'class' => 'yii\db\Connection',
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 *             'dsn' => 'oci:dbname=LOCAL_XE',
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 *              ...
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 *         ]
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 *         'mutex' => [
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 *             'class' => 'yii\mutex\OracleMutex',
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 *             'lockMode' => 'NL_MODE',
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 *             'releaseOnCommit' => true,
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 *              ...
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 *         ],
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 *     ],
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 * ]
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 * ```
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 *
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 * @see https://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_lock.htm#ARPLS021
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 * @see Mutex
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 *
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 * @author Alexander Zlakomanov <zlakomanoff@gmail.com>
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 * @since 2.0.10
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 */
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class OracleMutex extends DbMutex
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{
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    /** available lock modes */
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    const MODE_X = 'X_MODE';
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    const MODE_NL = 'NL_MODE';
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    const MODE_S = 'S_MODE';
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    const MODE_SX = 'SX_MODE';
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    const MODE_SS = 'SS_MODE';
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    const MODE_SSX = 'SSX_MODE';
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    /**
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     * @var string lock mode to be used.
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     * @see https://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_lock.htm#ARPLS021#CHDBCFDI
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     */
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    public $lockMode = self::MODE_X;
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    /**
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     * @var bool whether to release lock on commit.
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     */
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    public $releaseOnCommit = false;
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    /**
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     * Initializes Oracle specific mutex component implementation.
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     * @throws InvalidConfigException if [[db]] is not Oracle connection.
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     */
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    public function init()
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    {
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        parent::init();
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        if (strncmp($this->db->driverName, 'oci', 3) !== 0 && strncmp($this->db->driverName, 'odbc', 4) !== 0) {
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            throw new InvalidConfigException('In order to use OracleMutex connection must be configured to use Oracle database.');
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        }
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    }
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    /**
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     * Acquires lock by given name.
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     * @see https://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_lock.htm#ARPLS021
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     * @param string $name of the lock to be acquired.
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     * @param int $timeout time (in seconds) to wait for lock to become released.
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     * @return bool acquiring result.
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     */
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    protected function acquireLock($name, $timeout = 0)
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    {
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        $lockStatus = null;
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        // clean vars before using
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        $releaseOnCommit = $this->releaseOnCommit ? 'TRUE' : 'FALSE';
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        $timeout = abs((int) $timeout);
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        // inside pl/sql scopes pdo binding not working correctly :(
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        $this->db->useMaster(function ($db) use ($name, $timeout, $releaseOnCommit, &$lockStatus) {
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            /** @var \yii\db\Connection $db */
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            $db->createCommand(
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                'DECLARE
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    handle VARCHAR2(128);
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BEGIN
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    DBMS_LOCK.ALLOCATE_UNIQUE(:name, handle);
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    :lockStatus := DBMS_LOCK.REQUEST(handle, DBMS_LOCK.' . $this->lockMode . ', ' . $timeout . ', ' . $releaseOnCommit . ');
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END;',
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                [':name' => $name]
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            )
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            ->bindParam(':lockStatus', $lockStatus, PDO::PARAM_INT, 1)
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            ->execute();
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        });
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        return $lockStatus === 0 || $lockStatus === '0';
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    }
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    /**
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     * Releases lock by given name.
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     * @param string $name of the lock to be released.
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     * @return bool release result.
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     * @see https://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_lock.htm#ARPLS021
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     */
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    protected function releaseLock($name)
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    {
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        $releaseStatus = null;
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        $this->db->useMaster(function ($db) use ($name, &$releaseStatus) {
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            /** @var \yii\db\Connection $db */
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            $db->createCommand(
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                'DECLARE
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    handle VARCHAR2(128);
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BEGIN
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    DBMS_LOCK.ALLOCATE_UNIQUE(:name, handle);
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    :result := DBMS_LOCK.RELEASE(handle);
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END;',
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                [':name' => $name]
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            )
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            ->bindParam(':result', $releaseStatus, PDO::PARAM_INT, 1)
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            ->execute();
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        });
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        return $releaseStatus === 0 || $releaseStatus === '0';
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    }
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}
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