/**
* Test Workload retry strategy
*
* @expectedException \Brightzone\GremlinDriver\ServerException
*
* @return void
*/
public function testRetry()
{
$db = new Connection(['host' => 'localhost', 'port' => 8182, 'graph' => 'graph', 'retryAttempts' => 5]);
$db->open();
$count = 0;
$workload = new Workload(function (&$count) {
$count++;
throw new \Brightzone\GremlinDriver\ServerException("test error", 500);
}, [&$count]);
try {
$response = $workload->linearRetry($db->retryAttempts);
} catch (\Exception $e) {
$this->assertEquals(5, $count, "incorrect number of attempts executed");
throw $e;
}
}
/**
* Run a callback in a transaction.
* The advantage of this is that it allows for fail-retry strategies
*
* @param callable $callback the code to execute within the scope of this transaction
* @param array $params The params to pass to the callback
*
* @return mixed the return value of the provided callable
*/
public function transaction(callable $callback, $params = [])
{
//create a callback from the callback to introduce transaction handling
$workload = new Workload(function (&$db, $callback, $params) {
try {
$db->transactionStart();
$result = call_user_func_array($callback, $params);
if ($db->_inTransaction) {
$db->transactionStop(TRUE);
}
return $result;
} catch (\Exception $e) {
/**
* We need to catch the exception again before the workload catches it
* this allows us to terminate the transaction properly before each retry attempt
*/
if ($db->_inTransaction) {
$db->transactionStop(FALSE);
}
throw $e;
}
}, [&$this, $callback, $params]);
$result = $workload->linearRetry($this->retryAttempts);
return $result;
}