Amounts
Every payment data object takes an AmountInput for its amount: an Amount, or a whole number or bigint. A plain whole number is a whole amount; use the Amount value object from @laranex/myanmar-payments when you need decimals. Fractional numbers are never accepted, so an amount is never rounded on its way into a signature.
import { Amount } from '@laranex/myanmar-payments';
Amount.kyat(10000); // whole amount
Amount.parse('10000.50'); // decimal amount
// this.payments is the injected MyanmarPaymentsService
const payment = await this.payments.kbzPay().pwa({
orderId: `ORDER_${order.id}`,
amount: Amount.parse('10000.50'), // or simply 10000
callbackUrl: 'https://shop.test/payments/kbz/callback',
});Creating Amounts
| Constructor | Accepts |
|---|---|
Amount.kyat(amount: number | bigint) | A whole amount, 0 or more: a safe integer number or a bigint. Works for whole units of any currency |
Amount.parse(amount: string) | Plain digits with an optional decimal part: 1000, 1000.50, 0.5. Leading zeros of the whole part are dropped (007.50 becomes 7.50); the fraction is kept exactly |
Amount.from(amount: Amount | number | bigint) | An Amount as is, or a whole number through kyat(). The gateways use it |
parse() rejects signs, exponents, spaces and thousands separators (-1, 1e5, 10, 1,000, 10., .5), and kyat() rejects negatives, fractions, NaN and integers beyond Number.MAX_SAFE_INTEGER (pass a bigint instead), by throwing InvalidPaymentDataError with an amount error.
An Amount exposes toString() (as given without leading zeros, also via JSON.stringify, which writes a string), decimalPlaces(), wholePart(), isZero(), isPositive() and equals(other), which compares with another Amount or a decimal string, ignoring leading zeros and trailing fractional zeros; text that is not a plain decimal is never equal.
Gateway Rules
Each gateway checks the amount against its official documentation when you start the payment, before any request is sent:
| Gateway | Decimals | Other rules |
|---|---|---|
| KBZ Pay | Up to 2 places | Greater than 0, MMK only |
| Wave Money | No | Greater than 0, MMK only. The total defaults to the sum of the items |
| AYA Payment Gateway | No | Greater than 0, MMK only |
| Yoma MMQR | No | Greater than 0 |
| CyberSource | Any | 0 or more, at most 15 characters, any ISO 4217 currency |
A violation throws InvalidPaymentDataError, e.g. Wave Money does not accept decimal amounts; the amount field must be a whole number.
Amounts reported back by gateways (PaymentCallback.amount, PaymentStatusResult.amount) stay plain strings: they are the raw values the gateway sent. Compare them with your order before fulfilling.