public static function fromJson($json)
{
if (!isset($json->item) && !isset($json->checkout)) {
throw new \Exception('both checkout and item are null');
}
if (isset($json->item) && isset($json->checkout)) {
throw new \Exception('both checkout and item are non-null, only expected one of checkout or item');
}
$r = new Transaction();
$r->setId($json->id);
$r->setExternalId(isset($json->external_id) ? $json->external_id : null);
$r->setCreated($json->created);
$r->setState($json->state);
$r->setRevisionNumber($json->revision_number);
$r->setProject($json->project);
$r->setItem(isset($json->item) ? Item::fromJson($json->item) : null);
$r->setCheckout(isset($json->checkout) ? Checkout::fromJson($json->checkout) : null);
$r->setCustomer(Customer::fromJson($json->customer));
$r->setPrice(Price::fromJson($json->price));
$r->setPaymentMethod($json->payment_method);
$r->setTest(isset($json->test) ? $json->test : false);
return $r;
}
