/**
* @return \Google_Service_Datastore_ReadOptions
* @throws MissingFieldsException
* @throws ReadOptionsException
*/
public function build()
{
if ($this->readConsistency === null && $this->transaction === null) {
throw new MissingFieldsException(self::class, ['$readConsistency or $transaction']);
}
if ($this->readConsistency !== null && $this->transaction !== null) {
throw new ReadOptionsException('Read consistency cannot be set when transaction is set');
}
$readOptions = new \Google_Service_Datastore_ReadOptions();
if ($this->transaction !== null) {
$readOptions->setTransaction($this->transaction);
}
if ($this->readConsistency !== null) {
$readOptions->setReadConsistency($this->readConsistency->value());
}
return $readOptions;
}
/**
* If we are in a transaction, apply it to the request object
*
* @param $obj_request
* @return mixed
*/
private function applyTransaction($obj_request)
{
if (null !== $this->str_next_transaction) {
$obj_read_options = new \Google_Service_Datastore_ReadOptions();
$obj_read_options->setTransaction($this->str_next_transaction);
$obj_request->setReadOptions($obj_read_options);
$this->str_next_transaction = null;
}
return $obj_request;
}
/**
* Fetch an object from the datastore by key. Optionally indicate transaction.
* @param $key
* @param $txn
*/
private static function fetch_by_key($key, $txn = null)
{
$lookup_req = new Google_Service_Datastore_LookupRequest();
$lookup_req->setKeys([$key]);
if ($txn) {
// syslog(LOG_DEBUG, "fetching in transactional context $txn");
$ros = new Google_Service_Datastore_ReadOptions();
$ros->setTransaction($txn);
$lookup_req->setReadOptions($ros);
}
$response = DatastoreService::getInstance()->lookup($lookup_req);
$found = $response->getFound();
$extracted = static::extractQueryResults($found);
return $extracted;
}