subjectReader = $subjectReader; } /** * @inheritdoc */ public function build(array $buildSubject): array { $paymentDO = $this->subjectReader->readPayment($buildSubject); $payment = $paymentDO->getPayment(); $data = []; if ($payment instanceof Payment) { $data = [ 'transactionRequest' => [ 'poNumber' => $payment->getPoNumber() ] ]; } return $data; } }