executeQuery("DELETE FROM table"); * * Be aware that Connection#executeQuery is a method specifically for READ * operations only. * * This connection is limited to slave operations using the * Connection#executeQuery operation only, because it wouldn't be compatible * with the ORM or SchemaManager code otherwise. Both use all the other * operations in a context where writes could happen to a slave, which makes * this restricted approach necessary. * * You can manually connect to the master at any time by calling: * * $conn->connect('master'); * * Instantiation through the DriverManager looks like: * * @example * * $conn = DriverManager::getConnection(array( * 'wrapperClass' => 'Doctrine\DBAL\Connections\MasterSlaveConnection', * 'driver' => 'pdo_mysql', * 'master' => array('user' => '', 'password' => '', 'host' => '', 'dbname' => ''), * 'slaves' => array( * array('user' => 'slave1', 'password', 'host' => '', 'dbname' => ''), * array('user' => 'slave2', 'password', 'host' => '', 'dbname' => ''), * ) * )); * * You can also pass 'driverOptions' and any other documented option to each of this drivers to pass additional information. */ class MasterSlaveConnection extends Connection { /** * Master and slave connection (one of the randomly picked slaves). * * @var DriverConnection[]|null[] */ protected $connections = ['master' => null, 'slave' => null]; /** * You can keep the slave connection and then switch back to it * during the request if you know what you are doing. * * @var bool */ protected $keepSlave = false; /** * Creates Master Slave Connection. * * @param mixed[] $params * * @throws InvalidArgumentException */ public function __construct(array $params, Driver $driver, ?Configuration $config = null, ?EventManager $eventManager = null) { if (! isset($params['slaves'], $params['master'])) { throw new InvalidArgumentException('master or slaves configuration missing'); } if (count($params['slaves']) === 0) { throw new InvalidArgumentException('You have to configure at least one slaves.'); } $params['master']['driver'] = $params['driver']; foreach ($params['slaves'] as $slaveKey => $slave) { $params['slaves'][$slaveKey]['driver'] = $params['driver']; } $this->keepSlave = (bool) ($params['keepSlave'] ?? false); parent::__construct($params, $driver, $config, $eventManager); } /** * Checks if the connection is currently towards the master or not. * * @return bool */ public function isConnectedToMaster() { return $this->_conn !== null && $this->_conn === $this->connections['master']; } /** * {@inheritDoc} */ public function connect($connectionName = null) { $requestedConnectionChange = ($connectionName !== null); $connectionName = $connectionName ?: 'slave'; if ($connectionName !== 'slave' && $connectionName !== 'master') { throw new InvalidArgumentException('Invalid option to connect(), only master or slave allowed.'); } // If we have a connection open, and this is not an explicit connection // change request, then abort right here, because we are already done. // This prevents writes to the slave in case of "keepSlave" option enabled. if (isset($this->_conn) && $this->_conn && ! $requestedConnectionChange) { return false; } $forceMasterAsSlave = false; if ($this->getTransactionNestingLevel() > 0) { $connectionName = 'master'; $forceMasterAsSlave = true; } if (isset($this->connections[$connectionName]) && $this->connections[$connectionName]) { $this->_conn = $this->connections[$connectionName]; if ($forceMasterAsSlave && ! $this->keepSlave) { $this->connections['slave'] = $this->_conn; } return false; } if ($connectionName === 'master') { $this->connections['master'] = $this->_conn = $this->connectTo($connectionName); // Set slave connection to master to avoid invalid reads if (! $this->keepSlave) { $this->connections['slave'] = $this->connections['master']; } } else { $this->connections['slave'] = $this->_conn = $this->connectTo($connectionName); } if ($this->_eventManager->hasListeners(Events::postConnect)) { $eventArgs = new ConnectionEventArgs($this); $this->_eventManager->dispatchEvent(Events::postConnect, $eventArgs); } return true; } /** * Connects to a specific connection. * * @param string $connectionName * * @return DriverConnection */ protected function connectTo($connectionName) { $params = $this->getParams(); $driverOptions = $params['driverOptions'] ?? []; $connectionParams = $this->chooseConnectionConfiguration($connectionName, $params); $user = $connectionParams['user'] ?? null; $password = $connectionParams['password'] ?? null; return $this->_driver->connect($connectionParams, $user, $password, $driverOptions); } /** * @param string $connectionName * @param mixed[] $params * * @return mixed */ protected function chooseConnectionConfiguration($connectionName, $params) { if ($connectionName === 'master') { return $params['master']; } $config = $params['slaves'][array_rand($params['slaves'])]; if (! isset($config['charset']) && isset($params['master']['charset'])) { $config['charset'] = $params['master']['charset']; } return $config; } /** * {@inheritDoc} */ public function executeUpdate($query, array $params = [], array $types = []) { $this->connect('master'); return parent::executeUpdate($query, $params, $types); } /** * {@inheritDoc} */ public function beginTransaction() { $this->connect('master'); parent::beginTransaction(); } /** * {@inheritDoc} */ public function commit() { $this->connect('master'); parent::commit(); } /** * {@inheritDoc} */ public function rollBack() { $this->connect('master'); return parent::rollBack(); } /** * {@inheritDoc} */ public function delete($tableName, array $identifier, array $types = []) { $this->connect('master'); return parent::delete($tableName, $identifier, $types); } /** * {@inheritDoc} */ public function close() { unset($this->connections['master'], $this->connections['slave']); parent::close(); $this->_conn = null; $this->connections = ['master' => null, 'slave' => null]; } /** * {@inheritDoc} */ public function update($tableName, array $data, array $identifier, array $types = []) { $this->connect('master'); return parent::update($tableName, $data, $identifier, $types); } /** * {@inheritDoc} */ public function insert($tableName, array $data, array $types = []) { $this->connect('master'); return parent::insert($tableName, $data, $types); } /** * {@inheritDoc} */ public function exec($statement) { $this->connect('master'); return parent::exec($statement); } /** * {@inheritDoc} */ public function createSavepoint($savepoint) { $this->connect('master'); parent::createSavepoint($savepoint); } /** * {@inheritDoc} */ public function releaseSavepoint($savepoint) { $this->connect('master'); parent::releaseSavepoint($savepoint); } /** * {@inheritDoc} */ public function rollbackSavepoint($savepoint) { $this->connect('master'); parent::rollbackSavepoint($savepoint); } /** * {@inheritDoc} */ public function query() { $this->connect('master'); $args = func_get_args(); $logger = $this->getConfiguration()->getSQLLogger(); if ($logger) { $logger->startQuery($args[0]); } $statement = $this->_conn->query(...$args); $statement->setFetchMode($this->defaultFetchMode); if ($logger) { $logger->stopQuery(); } return $statement; } /** * {@inheritDoc} */ public function prepare($statement) { $this->connect('master'); return parent::prepare($statement); } }