fix(stripe): paymentIntent amount is now scale 2 (#1987)

* fix(stripe): paymentIntent amount is now scale 2

* refactor(stripe): applyScale util function now uses default scale

* chore(stripe): format

Author: beniaminmunteanu

packages/wallet/backend/src/stripe-integration/service.ts

@@ -7,7 +7,7 @@ import { StripeWebhookType } from './validation'
 import { WalletAddressService } from '../walletAddress/service'
 import { AccountService } from '../account/service'
 import { Transaction } from '../transaction/model'
-import { transformBalance } from '../utils/helpers'
+import { transformBalance, applyScale } from '../utils/helpers'
 
 export enum EventType {
   payment_intent_canceled = 'payment_intent.canceled',
@@ -49,7 +49,8 @@ export class StripeService implements IStripeService {
     const metadata = paymentIntent.metadata
     const receiving_address: string = metadata.receiving_address
     const currency: string = paymentIntent.currency
-    const amount: number = paymentIntent.amount
+
+    const scaledAmount = applyScale(paymentIntent.amount)
 
     try {
       const walletAddress =
@@ -63,7 +64,7 @@ export class StripeService implements IStripeService {
         await this.accountService.getGateHubWalletAddress(walletAddress)
 
       await this.gateHubClient.createTransaction({
-        amount,
+        amount: scaledAmount,
         vault_uuid: this.gateHubClient.getVaultUuid(currency.toUpperCase()),
         receiving_address: gateHubWalletId,
         sending_address: this.env.GATEHUB_SETTLEMENT_WALLET_ADDRESS,
@@ -76,7 +77,7 @@ export class StripeService implements IStripeService {
         accountId: walletAddress.accountId,
         paymentId: paymentIntent.id,
         assetCode: currency.toUpperCase(),
-        value: transformBalance(Number(amount), 2),
+        value: transformBalance(scaledAmount, 2),
         type: 'INCOMING',
         status: 'COMPLETED',
         description: 'Stripe Payment',

packages/wallet/backend/src/utils/helpers.ts

@@ -3,6 +3,7 @@ import { ObjectWithAnyKeys } from '@/shared/types'
 import { createHash, randomBytes } from 'crypto'
 import NodeCache from 'node-cache'
 import { env } from '@/config/env'
+import { DEFAULT_ASSET_SCALE } from './consts'
 
 export const transformAmount = (
   amount: string | bigint,
@@ -24,6 +25,16 @@ export const transformBalance = (value: number, scale: number): bigint => {
   return BigInt(Math.floor(value * 10 ** scale))
 }
 
+export const applyScale = (
+  value: number,
+  scale: number = DEFAULT_ASSET_SCALE
+): number => {
+  const factor = 10 ** scale
+  const scaledValue = value * 10 ** -scale
+  const truncatedValue = Math.floor(scaledValue * factor) / factor
+  return truncatedValue
+}
+
 export function extractUuidFromUrl(url: string): string {
   const { pathname } = new URL(url)
   const id = pathname.match(
@@ -36,6 +47,7 @@ export function extractUuidFromUrl(url: string): string {
 
   return id
 }
+
 export const incomingPaymentRegexp =
   /\/incoming-payments\/[0-9a-fA-F]{8}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{12}$/
 

packages/wallet/backend/tests/stripe-integration/service.test.ts

@@ -141,7 +141,7 @@ describe('Stripe Service', (): void => {
       await stripeService.onWebHook(webhook)
 
       expect(mockGateHubClient.createTransaction).toHaveBeenCalledWith({
-        amount: webhook.data.object.amount,
+        amount: 10,
         vault_uuid: 'vault-uuid-123',
         receiving_address: 'gatehub-wallet-123',
         sending_address: env.GATEHUB_SETTLEMENT_WALLET_ADDRESS,
@@ -226,7 +226,7 @@ describe('Stripe Service', (): void => {
       )
 
       expect(mockGateHubClient.createTransaction).toHaveBeenCalledWith({
-        amount: webhook.data.object.amount,
+        amount: 10,
         vault_uuid: 'vault-uuid-123',
         receiving_address: 'gatehub-wallet-123',
         sending_address: env.GATEHUB_SETTLEMENT_WALLET_ADDRESS,

packages/wallet/backend/tests/utils/helpers.test.ts

@@ -0,0 +1,22 @@
+import { applyScale } from '@/utils/helpers'
+
+describe('Utils Helper Functions', (): void => {
+  describe('applyScale', (): void => {
+    it('should correctly scale amounts with scale of 2', (): void => {
+      // Test various cases
+      expect(applyScale(1000, 2)).toBe(10)
+      expect(applyScale(1500, 2)).toBe(15)
+      expect(applyScale(1550, 2)).toBe(15.5)
+      expect(applyScale(1555, 2)).toBe(15.55)
+      expect(applyScale(1, 2)).toBe(0.01)
+    })
+
+    it('should handle zero correctly', (): void => {
+      expect(applyScale(0, 2)).toBe(0)
+    })
+
+    it('should use default scale if not provided', (): void => {
+      expect(applyScale(1000)).toBe(10)
+    })
+  })
+})