service/TransactionService.php
public static function create(Context $context, Transaction $transaction)
    {
        $response = NetLicensingService::getInstance()
            ->post($context, Constants::TRANSACTION_ENDPOINT_PATH, $transaction->asPropertiesMap());

        $createdTransaction = null;

        if (!empty($response->items->item[0])) {
            $createdTransaction = ItemToTransactionConverter::convert($response->items->item[0]);
            $createdTransaction->exists = true;
        }

        return $createdTransaction;
    }
public static function create(Context $context, Transaction $transaction)
    {
        $response = NetLicensingService::getInstance()
            ->post($context, Constants::TRANSACTION_ENDPOINT_PATH, $transaction->asPropertiesMap());

        $createdTransaction = null;

        if (!empty($response->items->item[0])) {
            $createdTransaction = ItemToTransactionConverter::convert($response->items->item[0]);
            $createdTransaction->exists = true;
        }

        return $createdTransaction;
    }
Creates new transaction object with given properties.See NetLicensingAPI for details:
https://www.labs64.de/confluence/display/NLICPUB/Transaction+Services#TransactionServices-Createtransaction

determines the vendor on whose behalf the call is performed
@param Context $context

non-null properties will be taken for the new object, null properties will either stay null, or will
be set to a default value, depending on property.
@param Transaction $transaction

return the newly created transaction object
@return Transaction|null
@throws \ErrorException
@throws RestException