refactor xmr rate module to exchange rate module for multi crypto support

backend/src/AppModule.ts

@@ -9,7 +9,7 @@ import {
     getCoingeckoConfig,
     getEncryptionConfig,
     getJwtConfig,
-    getKrakenConfig,
+    getCoinPaprikaConfig,
     getOrderConfig,
     getInvoiceConfig,
     getMoneroWalletConfig,
@@ -35,7 +35,7 @@ import { StorefrontCheckoutModule } from './modules/storefrontCheckout/Storefron
 import { StorefrontOrderModule } from './modules/storefrontOrder/StorefrontOrderModule';
 import { StorefrontCoreModule } from './modules/storefrontCore/StorefrontCoreModule';
 import { StorefrontProductModule } from './modules/storefrontProduct/StorefrontProductModule';
-import { XmrRateModule } from './modules/xmrRate/XmrRateModule';
+import { ExchangeRateModule } from './modules/exchangeRate/ExchangeRateModule';
 import { Config } from './types/Config';
 
 @Module({
@@ -49,7 +49,7 @@ import { Config } from './types/Config';
                 registerAs('app', getAppConfig),
                 registerAs('jwt', getJwtConfig),
                 registerAs('coingecko', getCoingeckoConfig),
-                registerAs('kraken', getKrakenConfig),
+                registerAs('coinPaprika', getCoinPaprikaConfig),
                 registerAs('encryption', getEncryptionConfig),
                 registerAs('shopSettings', getShopSettingsConfig),
                 registerAs('order', getOrderConfig),
@@ -74,7 +74,7 @@ import { Config } from './types/Config';
                 };
             }
         }),
-        XmrRateModule,
+        ExchangeRateModule,
         TypeOrmModule.forRootAsync({
             useFactory: (configService: ConfigService) => configService.get('postgres') as Config['postgres'],
             inject: [ConfigService]

backend/src/config/index.ts

@@ -191,7 +191,8 @@ export const getOrderConfig = (): OrderConfig => ({
 
 export const getInvoiceConfig = (): InvoiceConfig => ({
     minByMethod: {
-        [PaymentMethod.Xmr]: String(envInt('MONERO_MIN_INCOMING_ATOMIC'))
+        [PaymentMethod.Xmr]: String(envInt('MONERO_MIN_INCOMING_ATOMIC')),
+        [PaymentMethod.Btc]: String(envInt('BTC_MIN_INCOMING_ATOMIC'))
     }
 });
 

backend/src/modules/exchangeRate/ExchangeRateModule.ts

@@ -0,0 +1,8 @@
+import { Module } from '@nestjs/common';
+import { ExchangeRateService } from './services/ExchangeRateService';
+
+@Module({
+    providers: [ExchangeRateService],
+    exports: [ExchangeRateService]
+})
+export class ExchangeRateModule {}

backend/src/modules/exchangeRate/const/coinPaprikaIds.ts

@@ -0,0 +1,7 @@
+import type { ExchangeRatePaymentMethod } from './exchangeRatePaymentMethods';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
+
+export const COINPAPRIKA_ID_BY_PAYMENT_METHOD = {
+    [PaymentMethod.Xmr]: 'xmr-monero',
+    [PaymentMethod.Btc]: 'btc-bitcoin'
+} as const satisfies Record<ExchangeRatePaymentMethod, string>;

backend/src/modules/exchangeRate/const/coingeckoIds.ts

@@ -0,0 +1,7 @@
+import type { ExchangeRatePaymentMethod } from './exchangeRatePaymentMethods';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
+
+export const COINGECKO_ID_BY_PAYMENT_METHOD = {
+    [PaymentMethod.Xmr]: 'monero',
+    [PaymentMethod.Btc]: 'bitcoin'
+} as const satisfies Record<ExchangeRatePaymentMethod, string>;

backend/src/modules/exchangeRate/const/exchangeRatePaymentMethods.ts

@@ -0,0 +1,5 @@
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
+
+export const EXCHANGE_RATE_PAYMENT_METHODS = [PaymentMethod.Xmr, PaymentMethod.Btc] as const;
+
+export type ExchangeRatePaymentMethod = (typeof EXCHANGE_RATE_PAYMENT_METHODS)[number];

backend/src/modules/exchangeRate/dto/CoinPaprikaTickerResponseDto.ts

@@ -0,0 +1,43 @@
+import {
+    IsEnum,
+    IsNotEmpty,
+    Validate,
+    ValidatorConstraint,
+    type ValidationArguments,
+    type ValidatorConstraintInterface
+} from 'class-validator';
+import { ShopFiatCurrency } from '../../../types/ShopFiatCurrency';
+
+@ValidatorConstraint({ name: 'coinPaprikaResponse' })
+class CoinPaprikaResponseConstraint implements ValidatorConstraintInterface {
+    validate(response: unknown, args: ValidationArguments): boolean {
+        const { shopFiatCurrency } = args.object as CoinPaprikaTickerResponseDto;
+
+        if (!shopFiatCurrency || typeof response !== 'object' || response === null) {
+            return false;
+        }
+
+        const quotes = (response as { quotes?: unknown }).quotes;
+
+        if (typeof quotes !== 'object' || quotes === null) {
+            return false;
+        }
+
+        const quote = (quotes as Record<string, { price?: number }>)[shopFiatCurrency];
+
+        return typeof quote?.price === 'number' && Number.isFinite(quote.price) && quote.price > 0;
+    }
+
+    defaultMessage(): string {
+        return 'CoinPaprika fiat quote price must be a positive number';
+    }
+}
+
+export class CoinPaprikaTickerResponseDto {
+    @IsEnum(ShopFiatCurrency)
+    shopFiatCurrency: ShopFiatCurrency;
+
+    @IsNotEmpty()
+    @Validate(CoinPaprikaResponseConstraint)
+    response: { quotes: Record<string, { price: number }> };
+}

backend/src/modules/exchangeRate/dto/CoingeckoSimplePriceResponseDto.ts

@@ -0,0 +1,55 @@
+import {
+    IsArray,
+    IsEnum,
+    IsNotEmpty,
+    IsObject,
+    IsString,
+    Validate,
+    ValidatorConstraint,
+    type ValidationArguments,
+    type ValidatorConstraintInterface
+} from 'class-validator';
+import { ShopFiatCurrency } from '../../../types/ShopFiatCurrency';
+
+@ValidatorConstraint({ name: 'coingeckoResponse' })
+class CoingeckoResponseConstraint implements ValidatorConstraintInterface {
+    validate(response: Record<string, unknown>, args: ValidationArguments): boolean {
+        const { shopFiatCurrency, coinIds } = args.object as CoingeckoSimplePriceResponseDto;
+
+        if (!shopFiatCurrency || coinIds.length === 0) {
+            return false;
+        }
+
+        const fiatKey = shopFiatCurrency.toLowerCase();
+
+        return coinIds.every(coinId => {
+            const coin = response[coinId];
+
+            if (typeof coin !== 'object' || coin === null) {
+                return false;
+            }
+
+            const rate = coin[fiatKey];
+
+            return typeof rate === 'number' && Number.isFinite(rate) && rate > 0;
+        });
+    }
+
+    defaultMessage(): string {
+        return 'CoinGecko coin fiat rate must be a positive number';
+    }
+}
+
+export class CoingeckoSimplePriceResponseDto {
+    @IsEnum(ShopFiatCurrency)
+    shopFiatCurrency: ShopFiatCurrency;
+
+    @IsArray()
+    @IsString({ each: true })
+    coinIds: string[];
+
+    @IsNotEmpty()
+    @IsObject()
+    @Validate(CoingeckoResponseConstraint)
+    response: Record<string, Record<string, number>>;
+}

backend/src/modules/exchangeRate/services/ExchangeRateService.spec.ts

@@ -0,0 +1,245 @@
+import { Logger } from '@nestjs/common';
+import type { ConfigService } from '@nestjs/config';
+import axios from 'axios';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
+import { ExchangeRateService } from './ExchangeRateService';
+
+jest.mock('axios');
+
+const mockedAxios = axios as jest.Mocked<typeof axios>;
+
+const buildCoinPaprikaTicker = (price: number, fiat = 'USD') => ({
+    quotes: { [fiat]: { price } }
+});
+
+const buildCoinPaprikaAxiosMock =
+    (xmrPrice: number, btcPrice: number, fiat = 'USD') =>
+    (url: string) => {
+        if (url === `https://coinpaprika.test/v1/tickers/xmr-monero?quotes=${fiat}`) {
+            return Promise.resolve({ data: buildCoinPaprikaTicker(xmrPrice, fiat) });
+        }
+
+        if (url === `https://coinpaprika.test/v1/tickers/btc-bitcoin?quotes=${fiat}`) {
+            return Promise.resolve({ data: buildCoinPaprikaTicker(btcPrice, fiat) });
+        }
+
+        return Promise.reject(new Error(`unexpected url: ${url}`));
+    };
+
+describe('ExchangeRateService', () => {
+    let service: ExchangeRateService;
+    let configService: {
+        get: jest.Mock;
+    };
+    let warnLogSpy: jest.SpiedFunction<typeof Logger.prototype.warn>;
+    let errorLogSpy: jest.SpiedFunction<typeof Logger.prototype.error>;
+    let logSpy: jest.SpiedFunction<typeof Logger.prototype.log>;
+
+    beforeEach(() => {
+        warnLogSpy = jest.spyOn(Logger.prototype, 'warn').mockImplementation(() => undefined);
+        errorLogSpy = jest.spyOn(Logger.prototype, 'error').mockImplementation(() => undefined);
+        logSpy = jest.spyOn(Logger.prototype, 'log').mockImplementation(() => undefined);
+
+        configService = {
+            get: jest.fn((key: string) => {
+                if (key === 'shopSettings') {
+                    return { shopFiatCurrency: 'USD' };
+                }
+
+                if (key === 'coingecko') {
+                    return { apiBaseUrl: 'https://coingecko.test', rateFetchTimeoutMs: 5000 };
+                }
+
+                if (key === 'coinPaprika') {
+                    return { apiBaseUrl: 'https://coinpaprika.test/v1', rateFetchTimeoutMs: 5000 };
+                }
+
+                return undefined;
+            })
+        };
+
+        service = new ExchangeRateService(configService as unknown as ConfigService);
+        mockedAxios.get.mockReset();
+    });
+
+    afterEach(() => {
+        warnLogSpy.mockRestore();
+        errorLogSpy.mockRestore();
+        logSpy.mockRestore();
+    });
+
+    it('stores batched CoinGecko rates when the fetch succeeds', async () => {
+        mockedAxios.get.mockResolvedValueOnce({
+            data: {
+                monero: { usd: 152.3456 },
+                bitcoin: { usd: 95_432.1987 }
+            }
+        });
+
+        await service.fetchLiveRates();
+
+        expect(mockedAxios.get).toHaveBeenCalledWith(
+            'https://coingecko.test/simple/price?ids=monero,bitcoin&vs_currencies=usd',
+            { timeout: 5000 }
+        );
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(152.35);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(95_432.2);
+    });
+
+    it('falls back to CoinPaprika when CoinGecko fails', async () => {
+        mockedAxios.get
+            .mockRejectedValueOnce(new Error('coingecko down'))
+            .mockImplementation(buildCoinPaprikaAxiosMock(149.876, 94_999.5));
+
+        await service.fetchLiveRates();
+
+        expect(warnLogSpy).toHaveBeenCalled();
+        expect(mockedAxios.get).toHaveBeenCalledWith(
+            'https://coinpaprika.test/v1/tickers/xmr-monero?quotes=USD',
+            { timeout: 5000 }
+        );
+        expect(mockedAxios.get).toHaveBeenCalledWith(
+            'https://coinpaprika.test/v1/tickers/btc-bitcoin?quotes=USD',
+            { timeout: 5000 }
+        );
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(149.88);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(94_999.5);
+    });
+
+    it('leaves cached rates null when both providers fail on the first fetch', async () => {
+        mockedAxios.get
+            .mockRejectedValueOnce(new Error('coingecko down'))
+            .mockRejectedValue(new Error('coinpaprika down'));
+
+        await service.fetchLiveRates();
+
+        expect(errorLogSpy).toHaveBeenCalled();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBeNull();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBeNull();
+    });
+
+    it('falls back to CoinPaprika when CoinGecko returns an invalid payload', async () => {
+        mockedAxios.get
+            .mockResolvedValueOnce({ data: { monero: { usd: -1 }, bitcoin: { usd: 95_000 } } })
+            .mockImplementation(buildCoinPaprikaAxiosMock(151.11, 95_111.11));
+
+        await service.fetchLiveRates();
+
+        expect(warnLogSpy).toHaveBeenCalled();
+        expect(logSpy).toHaveBeenCalledWith('Successfully fetched live rates from CoinPaprika for USD');
+        expect(mockedAxios.get).toHaveBeenCalledTimes(3);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(151.11);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(95_111.11);
+    });
+
+    it('falls back to CoinPaprika when CoinGecko omits a coin', async () => {
+        mockedAxios.get
+            .mockResolvedValueOnce({ data: { monero: { usd: 150 } } })
+            .mockImplementation(buildCoinPaprikaAxiosMock(149.5, 94_000));
+
+        await service.fetchLiveRates();
+
+        expect(warnLogSpy).toHaveBeenCalled();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(149.5);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(94_000);
+    });
+
+    it('leaves cached rates null when CoinPaprika returns an invalid payload for one coin', async () => {
+        mockedAxios.get.mockRejectedValueOnce(new Error('coingecko down')).mockImplementation((url: string) => {
+            if (url === 'https://coinpaprika.test/v1/tickers/xmr-monero?quotes=USD') {
+                return Promise.resolve({ data: buildCoinPaprikaTicker(151.11) });
+            }
+
+            if (url === 'https://coinpaprika.test/v1/tickers/btc-bitcoin?quotes=USD') {
+                return Promise.resolve({ data: { quotes: { USD: { price: -1 } } } });
+            }
+
+            return Promise.reject(new Error(`unexpected url: ${url}`));
+        });
+
+        await service.fetchLiveRates();
+
+        expect(errorLogSpy).toHaveBeenCalled();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBeNull();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBeNull();
+    });
+
+    it('keeps the previous live rates when a refresh fails after a successful fetch', async () => {
+        mockedAxios.get.mockResolvedValueOnce({
+            data: {
+                monero: { usd: 140 },
+                bitcoin: { usd: 90_000 }
+            }
+        });
+        await service.fetchLiveRates();
+
+        mockedAxios.get
+            .mockRejectedValueOnce(new Error('coingecko down'))
+            .mockRejectedValue(new Error('coinpaprika down'));
+        await service.fetchLiveRates();
+
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(140);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(90_000);
+    });
+
+    it('keeps the previous live rates when CoinPaprika returns an invalid payload for one coin on refresh', async () => {
+        mockedAxios.get.mockResolvedValueOnce({
+            data: {
+                monero: { usd: 140 },
+                bitcoin: { usd: 90_000 }
+            }
+        });
+        await service.fetchLiveRates();
+
+        mockedAxios.get.mockRejectedValueOnce(new Error('coingecko down')).mockImplementation((url: string) => {
+            if (url === 'https://coinpaprika.test/v1/tickers/xmr-monero?quotes=USD') {
+                return Promise.resolve({ data: buildCoinPaprikaTicker(151.11) });
+            }
+
+            if (url === 'https://coinpaprika.test/v1/tickers/btc-bitcoin?quotes=USD') {
+                return Promise.resolve({ data: { quotes: { USD: { price: -1 } } } });
+            }
+
+            return Promise.reject(new Error(`unexpected url: ${url}`));
+        });
+        await service.fetchLiveRates();
+
+        expect(errorLogSpy).toHaveBeenCalled();
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(140);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(90_000);
+    });
+
+    it('uses the shop fiat currency when building provider URLs', async () => {
+        configService.get.mockImplementation((key: string) => {
+            if (key === 'shopSettings') {
+                return { shopFiatCurrency: 'EUR' };
+            }
+
+            if (key === 'coingecko') {
+                return { apiBaseUrl: 'https://coingecko.test', rateFetchTimeoutMs: 5000 };
+            }
+
+            if (key === 'coinPaprika') {
+                return { apiBaseUrl: 'https://coinpaprika.test/v1', rateFetchTimeoutMs: 5000 };
+            }
+
+            return undefined;
+        });
+
+        mockedAxios.get.mockResolvedValueOnce({
+            data: {
+                monero: { eur: 130.5 },
+                bitcoin: { eur: 88_000.4 }
+            }
+        });
+
+        await service.fetchLiveRates();
+
+        expect(mockedAxios.get).toHaveBeenCalledWith(
+            'https://coingecko.test/simple/price?ids=monero,bitcoin&vs_currencies=eur',
+            { timeout: 5000 }
+        );
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Xmr)).toBe(130.5);
+        expect(service.getLiveFiatPerCrypto(PaymentMethod.Btc)).toBe(88_000.4);
+    });
+});

backend/src/modules/exchangeRate/services/ExchangeRateService.ts

@@ -0,0 +1,156 @@
+import { Injectable, Logger, OnModuleInit } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { Cron, CronExpression } from '@nestjs/schedule';
+import { plainToInstance } from 'class-transformer';
+import { validateSync } from 'class-validator';
+import axios from 'axios';
+import type { Config } from '../../../types/Config';
+import { getErrorMessage } from '../../../utils/getErrorMessage';
+import { COINGECKO_ID_BY_PAYMENT_METHOD } from '../const/coingeckoIds';
+import { COINPAPRIKA_ID_BY_PAYMENT_METHOD } from '../const/coinPaprikaIds';
+import { EXCHANGE_RATE_PAYMENT_METHODS, type ExchangeRatePaymentMethod } from '../const/exchangeRatePaymentMethods';
+import { CoingeckoSimplePriceResponseDto } from '../dto/CoingeckoSimplePriceResponseDto';
+import { CoinPaprikaTickerResponseDto } from '../dto/CoinPaprikaTickerResponseDto';
+import type { FiatPerCryptoRates } from '../types/FiatPerCryptoRates';
+import { extractCoingeckoSimplePrice } from '../utils/extractCoingeckoSimplePrice';
+import { extractCoinPaprikaTickerPrice } from '../utils/extractCoinPaprikaTickerPrice';
+
+@Injectable()
+export class ExchangeRateService implements OnModuleInit {
+    private readonly logger = new Logger(ExchangeRateService.name);
+
+    private liveFiatPerCrypto = Object.fromEntries(
+        EXCHANGE_RATE_PAYMENT_METHODS.map(method => [method, null])
+    ) as Record<ExchangeRatePaymentMethod, number | null>;
+
+    constructor(private readonly configService: ConfigService) {}
+
+    async onModuleInit(): Promise<void> {
+        await this.fetchLiveRates();
+    }
+
+    getLiveFiatPerCrypto(method: ExchangeRatePaymentMethod): number | null {
+        return this.liveFiatPerCrypto[method];
+    }
+
+    @Cron(CronExpression.EVERY_5_MINUTES)
+    async fetchLiveRates(): Promise<void> {
+        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
+
+        try {
+            const rates = await this.fetchRatesFromCoingecko();
+
+            this.applyRates(rates);
+        } catch {
+            this.logger.warn(`CoinGecko rate fetch failed for ${shopFiatCurrency}, trying CoinPaprika`);
+
+            try {
+                const rates = await this.fetchRatesFromCoinPaprika();
+
+                this.applyRates(rates);
+
+                this.logger.log(`Successfully fetched live rates from CoinPaprika for ${shopFiatCurrency}`);
+            } catch (error) {
+                this.logger.error(
+                    `Failed to fetch live rates from CoinGecko and CoinPaprika for ${shopFiatCurrency}: ${getErrorMessage(error)}`
+                );
+            }
+        }
+    }
+
+    private async fetchRatesFromCoingecko(): Promise<FiatPerCryptoRates> {
+        const { rateFetchTimeoutMs } = this.configService.get('coingecko') as Config['coingecko'];
+        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
+
+        const url = this.buildCoingeckoRateUrl();
+
+        const { data } = await axios.get<unknown>(url, {
+            timeout: rateFetchTimeoutMs
+        });
+
+        const coinIds = EXCHANGE_RATE_PAYMENT_METHODS.map(method => COINGECKO_ID_BY_PAYMENT_METHOD[method]);
+
+        const dto = plainToInstance(CoingeckoSimplePriceResponseDto, {
+            response: data,
+            shopFiatCurrency,
+            coinIds
+        });
+
+        const errors = validateSync(dto);
+
+        if (errors.length > 0) {
+            throw new Error('CoinGecko response validation failed');
+        }
+
+        const rates = {} as FiatPerCryptoRates;
+
+        for (const method of EXCHANGE_RATE_PAYMENT_METHODS) {
+            const coinId = COINGECKO_ID_BY_PAYMENT_METHOD[method];
+
+            const price = extractCoingeckoSimplePrice(dto.response, coinId, shopFiatCurrency);
+
+            if (price === null) {
+                throw new Error(`CoinGecko response validation failed for coin ${coinId}`);
+            }
+
+            rates[method] = price;
+        }
+
+        return rates;
+    }
+
+    private async fetchRatesFromCoinPaprika(): Promise<FiatPerCryptoRates> {
+        const { apiBaseUrl, rateFetchTimeoutMs } = this.configService.get('coinPaprika') as Config['coinPaprika'];
+        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
+
+        const rates = {} as FiatPerCryptoRates;
+
+        await Promise.all(
+            EXCHANGE_RATE_PAYMENT_METHODS.map(async method => {
+                const coinId = COINPAPRIKA_ID_BY_PAYMENT_METHOD[method];
+                const url = `${apiBaseUrl}/tickers/${coinId}?quotes=${shopFiatCurrency}`;
+
+                const { data } = await axios.get<unknown>(url, {
+                    timeout: rateFetchTimeoutMs
+                });
+
+                const dto = plainToInstance(CoinPaprikaTickerResponseDto, {
+                    response: data,
+                    shopFiatCurrency
+                });
+
+                const errors = validateSync(dto);
+
+                if (errors.length > 0) {
+                    throw new Error(`CoinPaprika response validation failed for coin ${coinId}`);
+                }
+
+                const price = extractCoinPaprikaTickerPrice(dto.response, shopFiatCurrency);
+
+                if (price === null) {
+                    throw new Error(`CoinPaprika response validation failed for coin ${coinId}`);
+                }
+
+                rates[method] = price;
+            })
+        );
+
+        return rates;
+    }
+
+    private buildCoingeckoRateUrl(): string {
+        const { apiBaseUrl } = this.configService.get('coingecko') as Config['coingecko'];
+        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
+
+        const coinIds = EXCHANGE_RATE_PAYMENT_METHODS.map(method => COINGECKO_ID_BY_PAYMENT_METHOD[method]).join(',');
+        const vs = shopFiatCurrency.toLowerCase();
+
+        return `${apiBaseUrl}/simple/price?ids=${coinIds}&vs_currencies=${vs}`;
+    }
+
+    private applyRates(rates: FiatPerCryptoRates): void {
+        for (const method of EXCHANGE_RATE_PAYMENT_METHODS) {
+            this.liveFiatPerCrypto[method] = rates[method];
+        }
+    }
+}

backend/src/modules/exchangeRate/types/FiatPerCryptoRates.ts

@@ -0,0 +1,3 @@
+import type { ExchangeRatePaymentMethod } from '../const/exchangeRatePaymentMethods';
+
+export type FiatPerCryptoRates = Record<ExchangeRatePaymentMethod, number>;

backend/src/modules/exchangeRate/utils/extractCoinPaprikaTickerPrice.ts

@@ -0,0 +1,25 @@
+import Decimal from 'decimal.js';
+import type { ShopFiatCurrency } from '../../../types/ShopFiatCurrency';
+
+export const extractCoinPaprikaTickerPrice = (
+    response: { quotes: Record<string, { price: number }> },
+    shopFiatCurrency: ShopFiatCurrency
+): number | null => {
+    const quote = response.quotes[shopFiatCurrency];
+
+    if (!quote) {
+        return null;
+    }
+
+    const rate = quote.price;
+
+    if (typeof rate !== 'number' || !Number.isFinite(rate) || rate <= 0) {
+        return null;
+    }
+
+    try {
+        return new Decimal(rate).toDecimalPlaces(2).toNumber();
+    } catch {
+        return null;
+    }
+};

backend/src/modules/exchangeRate/utils/extractCoingeckoSimplePrice.ts

@@ -0,0 +1,28 @@
+import Decimal from 'decimal.js';
+import type { ShopFiatCurrency } from '../../../types/ShopFiatCurrency';
+
+export const extractCoingeckoSimplePrice = (
+    coins: Record<string, Record<string, number>>,
+    coinId: string,
+    shopFiatCurrency: ShopFiatCurrency
+): number | null => {
+    const coin = coins[coinId];
+
+    if (!coin) {
+        return null;
+    }
+
+    const fiatKey = shopFiatCurrency.toLowerCase();
+
+    const rate = coin[fiatKey];
+
+    if (typeof rate !== 'number' || !Number.isFinite(rate) || rate <= 0) {
+        return null;
+    }
+
+    try {
+        return new Decimal(rate).toDecimalPlaces(2).toNumber();
+    } catch {
+        return null;
+    }
+};

backend/src/modules/payment/PaymentModule.ts

@@ -1,7 +1,7 @@
 import { Module } from '@nestjs/common';
 import { TypeOrmModule } from '@nestjs/typeorm';
 import { MoneroWalletModule } from '../moneroWallet/MoneroWalletModule';
-import { XmrRateModule } from '../xmrRate/XmrRateModule';
+import { ExchangeRateModule } from '../exchangeRate/ExchangeRateModule';
 import { Invoice } from './entities/Invoice';
 import { InvoiceMoneroDetails } from './entities/InvoiceMoneroDetails';
 import { InvoicePayment } from './entities/InvoicePayment';
@@ -12,7 +12,7 @@ import { InvoiceService } from './services/InvoiceService';
     imports: [
         TypeOrmModule.forFeature([Invoice, InvoicePayment, InvoiceMoneroDetails]),
         MoneroWalletModule,
-        XmrRateModule
+        ExchangeRateModule
     ],
     providers: [InvoicePaymentService, InvoiceService],
     exports: [InvoiceService, TypeOrmModule.forFeature([Invoice])]

backend/src/modules/payment/services/InvoiceService.spec.ts

@@ -2,7 +2,7 @@ import { Logger, ServiceUnavailableException } from '@nestjs/common';
 import type { ConfigService } from '@nestjs/config';
 import type { Repository } from 'typeorm';
 import type { MoneroWalletRpcClient } from '../../moneroWallet/services/MoneroWalletRpcClient';
-import type { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import type { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
 import { Invoice } from '../entities/Invoice';
 import { InvoiceReason } from '../types/InvoiceReason';
 import { PaymentMethod } from '../types/PaymentMethod';
@@ -22,8 +22,8 @@ describe('InvoiceService', () => {
     let walletRpcClient: {
         createAddress: jest.Mock;
     };
-    let xmrRateService: {
-        getLiveFiatPerXmr: jest.Mock;
+    let exchangeRateService: {
+        getLiveFiatPerCrypto: jest.Mock;
     };
     let errorLogSpy: jest.SpiedFunction<typeof Logger.prototype.error>;
 
@@ -60,15 +60,15 @@ describe('InvoiceService', () => {
             })
         };
 
-        xmrRateService = {
-            getLiveFiatPerXmr: jest.fn().mockReturnValue(150)
+        exchangeRateService = {
+            getLiveFiatPerCrypto: jest.fn().mockReturnValue(150)
         };
 
         service = new InvoiceService(
             invoiceRepo as unknown as Repository<Invoice>,
             configService as unknown as ConfigService,
             walletRpcClient as unknown as MoneroWalletRpcClient,
-            xmrRateService as unknown as XmrRateService
+            exchangeRateService as unknown as ExchangeRateService
         );
     });
 
@@ -85,7 +85,7 @@ describe('InvoiceService', () => {
         });
 
     it('throws when the live XMR rate is unavailable for checkout invoices', async () => {
-        xmrRateService.getLiveFiatPerXmr.mockReturnValue(null);
+        exchangeRateService.getLiveFiatPerCrypto.mockReturnValue(null);
 
         await expect(issueCheckoutInvoice()).rejects.toThrow(
             new ServiceUnavailableException("We can't show a price right now. Please try again in a few minutes.")
@@ -169,7 +169,7 @@ describe('InvoiceService', () => {
     });
 
     it('uses shipping-specific messages and address labels for shipping invoices', async () => {
-        xmrRateService.getLiveFiatPerXmr.mockReturnValue(null);
+        exchangeRateService.getLiveFiatPerCrypto.mockReturnValue(null);
 
         await expect(
             service.issueInvoice({
@@ -184,7 +184,7 @@ describe('InvoiceService', () => {
             )
         );
 
-        xmrRateService.getLiveFiatPerXmr.mockReturnValue(150);
+        exchangeRateService.getLiveFiatPerCrypto.mockReturnValue(150);
         walletRpcClient.createAddress.mockRejectedValue(new Error('rpc down'));
 
         await expect(

backend/src/modules/payment/services/InvoiceService.ts

@@ -9,7 +9,7 @@ import { convertFiatToXmr } from '../../../utils/monero/convertFiatToXmr';
 import { convertXmrToXmrAtomic } from '../../../utils/monero/convertXmrToXmrAtomic';
 import { resolveMinConfirmations } from '../../../utils/monero/resolveMinConfirmations';
 import { MoneroWalletRpcClient } from '../../moneroWallet/services/MoneroWalletRpcClient';
-import { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
 import { Invoice } from '../entities/Invoice';
 import { InvoiceReason } from '../types/InvoiceReason';
 import type { IssueInvoiceData } from '../types/IssueInvoiceData';
@@ -25,10 +25,10 @@ export class InvoiceService {
         private readonly invoiceRepo: Repository<Invoice>,
         private readonly configService: ConfigService,
         private readonly walletRpcClient: MoneroWalletRpcClient,
-        private readonly xmrRateService: XmrRateService
+        private readonly exchangeRateService: ExchangeRateService
     ) {}
 
-    async issueInvoice(data: IssueInvoiceData): Promise<Invoice> {
+    async issueInvoice(data: IssueInvoiceData): Promise<Invoice | undefined> {
         switch (data.paymentMethod) {
             case PaymentMethod.Xmr:
                 return this.issueXmrInvoice(data);
@@ -44,7 +44,7 @@ export class InvoiceService {
             contextId
         );
 
-        const fiatPerXmr = this.xmrRateService.getLiveFiatPerXmr();
+        const fiatPerXmr = this.exchangeRateService.getLiveFiatPerCrypto(PaymentMethod.Xmr);
 
         if (fiatPerXmr === null) {
             throw new ServiceUnavailableException(rateUnavailableMessage);

backend/src/modules/payment/types/PaymentMethod.ts

@@ -1,3 +1,4 @@
 export enum PaymentMethod {
-    Xmr = 'xmr'
+    Xmr = 'xmr',
+    Btc = 'btc'
 }

backend/src/modules/storefrontCart/StorefrontCartModule.ts

@@ -3,14 +3,14 @@ import { DiscountCodesModule } from '../discountCode/DiscountCodesModule';
 import { ProductsModule } from '../product/ProductsModule';
 import { StorefrontCoreModule } from '../storefrontCore/StorefrontCoreModule';
 import { StorefrontProductModule } from '../storefrontProduct/StorefrontProductModule';
-import { XmrRateModule } from '../xmrRate/XmrRateModule';
+import { ExchangeRateModule } from '../exchangeRate/ExchangeRateModule';
 import { StorefrontCartController } from './controllers/StorefrontCartController';
 import { StorefrontCartDiscountResolver } from './services/StorefrontCartDiscountResolver';
 import { StorefrontCartService } from './services/StorefrontCartService';
 import { StorefrontDiscountService } from './services/StorefrontDiscountService';
 
 @Module({
-    imports: [StorefrontCoreModule, StorefrontProductModule, ProductsModule, DiscountCodesModule, XmrRateModule],
+    imports: [StorefrontCoreModule, StorefrontProductModule, ProductsModule, DiscountCodesModule, ExchangeRateModule],
     controllers: [StorefrontCartController],
     providers: [StorefrontCartService, StorefrontDiscountService, StorefrontCartDiscountResolver],
     exports: [StorefrontCartService]

backend/src/modules/storefrontCart/services/StorefrontCartService.spec.ts

@@ -1,7 +1,8 @@
 import { BadRequestException } from '@nestjs/common';
 import { DeliveryMode } from '../../product/types/DeliveryMode';
 import type { StorefrontProductsService } from '../../storefrontProduct/services/StorefrontProductsService';
-import type { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import type { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
 import type { CookieCartLineExtended } from '../types/CookieCartLineExtended';
 import type { StorefrontDiscountService } from './StorefrontDiscountService';
 import { StorefrontCartService } from './StorefrontCartService';
@@ -29,8 +30,8 @@ describe('StorefrontCartService', () => {
         getStorefrontVariantsByIds: jest.Mock;
         getStorefrontVariant: jest.Mock;
     };
-    let xmrRateService: {
-        getLiveFiatPerXmr: jest.Mock;
+    let exchangeRateService: {
+        getLiveFiatPerCrypto: jest.Mock;
     };
     let discountService: {
         getDiscountStateForCart: jest.Mock;
@@ -43,8 +44,8 @@ describe('StorefrontCartService', () => {
             getStorefrontVariant: jest.fn().mockResolvedValue(buildVariant())
         };
 
-        xmrRateService = {
-            getLiveFiatPerXmr: jest.fn().mockReturnValue(150)
+        exchangeRateService = {
+            getLiveFiatPerCrypto: jest.fn().mockReturnValue(150)
         };
 
         discountService = {
@@ -58,7 +59,7 @@ describe('StorefrontCartService', () => {
 
         service = new StorefrontCartService(
             productsService as unknown as StorefrontProductsService,
-            xmrRateService as unknown as XmrRateService,
+            exchangeRateService as unknown as ExchangeRateService,
             discountService as unknown as StorefrontDiscountService
         );
     });
@@ -118,7 +119,7 @@ describe('StorefrontCartService', () => {
         });
 
         it('leaves cartTotalXmr null when no live rate is available', async () => {
-            xmrRateService.getLiveFiatPerXmr.mockReturnValue(null);
+            exchangeRateService.getLiveFiatPerCrypto.mockReturnValue(null);
 
             const summary = await service.getCartSummary([{ variantId, qty: 1 }], []);
 

backend/src/modules/storefrontCart/services/StorefrontCartService.ts

@@ -7,7 +7,8 @@ import type { CookieCart } from '../../storefrontCore/types/cart/CookieCart';
 import { getQtyByVariantIdFromCart } from '../../../utils/cart/getQtyByVariantIdFromCart';
 import { DeliveryMode } from '../../product/types/DeliveryMode';
 import { StorefrontProductsService } from '../../storefrontProduct/services/StorefrontProductsService';
-import { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
 import { convertFiatToXmr } from '../../../utils/monero/convertFiatToXmr';
 import { CookieCartLineDto } from '../dto/CookieCartLineDto';
 import type { CookieCartExtended } from '../types/CookieCartExtended';
@@ -22,7 +23,7 @@ import { StorefrontDiscountService } from './StorefrontDiscountService';
 export class StorefrontCartService {
     constructor(
         private readonly productsService: StorefrontProductsService,
-        private readonly xmrRateService: XmrRateService,
+        private readonly exchangeRateService: ExchangeRateService,
         private readonly discountService: StorefrontDiscountService
     ) {}
 
@@ -77,7 +78,7 @@ export class StorefrontCartService {
 
         const cartSubtotal = sumByKey(cartExtended, 'lineSubtotal');
         const discountState = await this.discountService.getDiscountStateForCart(discountCodes, cartExtended);
-        const fiatPerXmr = this.xmrRateService.getLiveFiatPerXmr();
+        const fiatPerXmr = this.exchangeRateService.getLiveFiatPerCrypto(PaymentMethod.Xmr);
         const cartTotalXmr = fiatPerXmr !== null ? convertFiatToXmr(discountState.cartTotalPrice, fiatPerXmr) : null;
         const hasManualLines = cartExtended.some(line => line.deliveryMode === DeliveryMode.Manual);
         const hasAutoLines = cartExtended.some(line => line.deliveryMode === DeliveryMode.Auto);

backend/src/modules/storefrontCore/StorefrontCoreModule.ts

@@ -1,7 +1,7 @@
 import { Module } from '@nestjs/common';
 import { EncryptionModule } from '../encryption/EncryptionModule';
 import { ShopSettingsModule } from '../shopSettings/ShopSettingsModule';
-import { XmrRateModule } from '../xmrRate/XmrRateModule';
+import { ExchangeRateModule } from '../exchangeRate/ExchangeRateModule';
 import { StorefrontErrorController } from './controllers/StorefrontErrorController';
 import { StorefrontPreferencesController } from './controllers/StorefrontPreferencesController';
 import { StorefrontExceptionFilter } from './filters/StorefrontExceptionFilter';
@@ -18,7 +18,7 @@ import { StorefrontSignedCookieService } from './services/StorefrontSignedCookie
 import { StorefrontThemeCookieService } from './services/StorefrontThemeCookieService';
 
 @Module({
-    imports: [ShopSettingsModule, XmrRateModule, EncryptionModule],
+    imports: [ShopSettingsModule, ExchangeRateModule, EncryptionModule],
     controllers: [StorefrontErrorController, StorefrontPreferencesController],
     providers: [
         StorefrontSignedCookieService,

backend/src/modules/storefrontCore/services/StorefrontShopViewService.spec.ts

@@ -2,7 +2,7 @@ import type { Request, Response } from 'express';
 import { ConfigService } from '@nestjs/config';
 import { StorefrontShopViewService } from './StorefrontShopViewService';
 import { ShopSettingsService } from '../../shopSettings/services/ShopSettingsService';
-import { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
 import { StorefrontCartCookieService } from './StorefrontCartCookieService';
 import { StorefrontFeedbackCookieService } from './StorefrontFeedbackCookieService';
 import { StorefrontOrderAuthCookieService } from './StorefrontOrderAuthCookieService';
@@ -50,9 +50,9 @@ describe('StorefrontShopViewService', () => {
             req: reqOverrides = {}
         } = overrides;
 
-        const xmrRateService = {
-            getLiveFiatPerXmr: jest.fn().mockReturnValue(fiatPerXmr)
-        } as unknown as XmrRateService;
+        const exchangeRateService = {
+            getLiveFiatPerCrypto: jest.fn().mockReturnValue(fiatPerXmr)
+        } as unknown as ExchangeRateService;
         const configService = {
             get: jest.fn().mockReturnValue(shopSettings)
         } as unknown as ConfigService;
@@ -73,7 +73,7 @@ describe('StorefrontShopViewService', () => {
         } as unknown as StorefrontThemeCookieService;
 
         const service = new StorefrontShopViewService(
-            xmrRateService,
+            exchangeRateService,
             configService,
             shopSettingsService,
             cartCookieService,

backend/src/modules/storefrontCore/services/StorefrontShopViewService.ts

@@ -7,7 +7,8 @@ import { getTotalCartQtyFromCart } from '../../../utils/cart/getTotalCartQtyFrom
 import { formatShortOrderId } from '../../../utils/order/formatShortOrderId';
 import { toAbsoluteUrl } from '../../../utils/toAbsoluteUrl';
 import { ShopSettingsService } from '../../shopSettings/services/ShopSettingsService';
-import { XmrRateService } from '../../xmrRate/services/XmrRateService';
+import { ExchangeRateService } from '../../exchangeRate/services/ExchangeRateService';
+import { PaymentMethod } from '../../payment/types/PaymentMethod';
 import type { AuthorizedOrderNavItem } from '../types/AuthorizedOrderNavItem';
 import type { ShopRenderLocals } from '../types/ShopRenderLocals';
 import type { StorefrontPageMeta } from '../types/StorefrontPageMeta';
@@ -22,7 +23,7 @@ import { StorefrontThemeCookieService } from './StorefrontThemeCookieService';
 @Injectable()
 export class StorefrontShopViewService {
     constructor(
-        private readonly xmrRateService: XmrRateService,
+        private readonly exchangeRateService: ExchangeRateService,
         private readonly configService: ConfigService,
         private readonly shopSettingsService: ShopSettingsService,
         private readonly cartCookieService: StorefrontCartCookieService,
@@ -40,7 +41,7 @@ export class StorefrontShopViewService {
 
         const { shopName, shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
 
-        const fiatPerXmr = this.xmrRateService.getLiveFiatPerXmr();
+        const fiatPerXmr = this.exchangeRateService.getLiveFiatPerCrypto(PaymentMethod.Xmr);
 
         const { logoUrl, faviconUrl, simplexLink, shippingNote } =
             await this.shopSettingsService.getStorefrontBranding();

backend/src/modules/xmrRate/XmrRateModule.ts

@@ -1,8 +0,0 @@
-import { Module } from '@nestjs/common';
-import { XmrRateService } from './services/XmrRateService';
-
-@Module({
-    providers: [XmrRateService],
-    exports: [XmrRateService]
-})
-export class XmrRateModule {}

backend/src/modules/xmrRate/dto/CoingeckoSimplePriceResponseDto.ts

@@ -1,39 +0,0 @@
-import {
-    IsEnum,
-    IsNotEmpty,
-    IsObject,
-    Validate,
-    ValidatorConstraint,
-    type ValidatorConstraintInterface,
-    type ValidationArguments
-} from 'class-validator';
-import { ShopFiatCurrency } from '../../../types/ShopFiatCurrency';
-
-@ValidatorConstraint({ name: 'coingeckoMoneroFiat' })
-class CoingeckoMoneroFiatConstraint implements ValidatorConstraintInterface {
-    validate(monero: Record<string, number>, args: ValidationArguments): boolean {
-        const { shopFiatCurrency } = args.object as CoingeckoSimplePriceResponseDto;
-
-        if (!shopFiatCurrency) {
-            return false;
-        }
-
-        const rate = monero[shopFiatCurrency.toLowerCase()];
-
-        return typeof rate === 'number' && Number.isFinite(rate) && rate > 0;
-    }
-
-    defaultMessage(): string {
-        return 'CoinGecko monero fiat rate must be a positive number';
-    }
-}
-
-export class CoingeckoSimplePriceResponseDto {
-    @IsEnum(ShopFiatCurrency)
-    shopFiatCurrency: ShopFiatCurrency;
-
-    @IsNotEmpty()
-    @IsObject()
-    @Validate(CoingeckoMoneroFiatConstraint)
-    monero: Record<string, number>;
-}

backend/src/modules/xmrRate/dto/KrakenTickerResponseDto.ts

@@ -1,56 +0,0 @@
-import {
-    ArrayMaxSize,
-    IsArray,
-    IsNotEmpty,
-    IsString,
-    Validate,
-    ValidatorConstraint,
-    type ValidatorConstraintInterface
-} from 'class-validator';
-import Decimal from 'decimal.js';
-
-@ValidatorConstraint({ name: 'krakenResult' })
-class KrakenResultConstraint implements ValidatorConstraintInterface {
-    validate(result: unknown): boolean {
-        if (typeof result !== 'object' || result === null) {
-            return false;
-        }
-
-        const pair = Object.values(result as Record<string, unknown>)[0];
-
-        if (typeof pair !== 'object' || pair === null) {
-            return false;
-        }
-
-        if (!('c' in pair)) {
-            return false;
-        }
-
-        if (!Array.isArray(pair.c) || pair.c.length < 1 || typeof pair.c[0] !== 'string') {
-            return false;
-        }
-
-        try {
-            const price = new Decimal(pair.c[0]);
-
-            return price.isFinite() && price.gt(0);
-        } catch {
-            return false;
-        }
-    }
-
-    defaultMessage(): string {
-        return 'Kraken ticker last price (c[0]) must be a positive number';
-    }
-}
-
-export class KrakenTickerResponseDto {
-    @IsArray()
-    @ArrayMaxSize(0)
-    @IsString({ each: true })
-    error: string[];
-
-    @IsNotEmpty()
-    @Validate(KrakenResultConstraint)
-    result: Record<string, { c: string[] }>;
-}

backend/src/modules/xmrRate/krakenXmrPairs.ts

@@ -1,10 +0,0 @@
-import { ShopFiatCurrency } from '../../types/ShopFiatCurrency';
-
-export const KRAKEN_XMR_PAIR_BY_FIAT: Record<ShopFiatCurrency, string> = {
-    [ShopFiatCurrency.Usd]: 'XMRUSD',
-    [ShopFiatCurrency.Eur]: 'XMREUR',
-    [ShopFiatCurrency.Gbp]: 'XMRGBP',
-    [ShopFiatCurrency.Cad]: 'XMRCAD',
-    [ShopFiatCurrency.Aud]: 'XMRAUD',
-    [ShopFiatCurrency.Chf]: 'XMRCHF'
-};

backend/src/modules/xmrRate/services/XmrRateService.spec.ts

@@ -1,127 +0,0 @@
-import { Logger } from '@nestjs/common';
-import type { ConfigService } from '@nestjs/config';
-import axios from 'axios';
-import { XmrRateService } from './XmrRateService';
-
-jest.mock('axios');
-
-const mockedAxios = axios as jest.Mocked<typeof axios>;
-
-describe('XmrRateService', () => {
-    let service: XmrRateService;
-    let configService: {
-        get: jest.Mock;
-    };
-    let warnLogSpy: jest.SpiedFunction<typeof Logger.prototype.warn>;
-    let errorLogSpy: jest.SpiedFunction<typeof Logger.prototype.error>;
-    let logSpy: jest.SpiedFunction<typeof Logger.prototype.log>;
-
-    beforeEach(() => {
-        warnLogSpy = jest.spyOn(Logger.prototype, 'warn').mockImplementation(() => undefined);
-        errorLogSpy = jest.spyOn(Logger.prototype, 'error').mockImplementation(() => undefined);
-        logSpy = jest.spyOn(Logger.prototype, 'log').mockImplementation(() => undefined);
-
-        configService = {
-            get: jest.fn((key: string) => {
-                if (key === 'shopSettings') {
-                    return { shopFiatCurrency: 'USD' };
-                }
-
-                if (key === 'coingecko') {
-                    return { apiBaseUrl: 'https://coingecko.test', xmrRateFetchTimeoutMs: 5000 };
-                }
-
-                if (key === 'kraken') {
-                    return { apiBaseUrl: 'https://kraken.test', xmrRateFetchTimeoutMs: 5000 };
-                }
-
-                return undefined;
-            })
-        };
-
-        service = new XmrRateService(configService as unknown as ConfigService);
-        mockedAxios.get.mockReset();
-    });
-
-    afterEach(() => {
-        warnLogSpy.mockRestore();
-        errorLogSpy.mockRestore();
-        logSpy.mockRestore();
-    });
-
-    it('stores the CoinGecko rate when the fetch succeeds', async () => {
-        mockedAxios.get.mockResolvedValueOnce({
-            data: { monero: { usd: 152.3456 } }
-        });
-
-        await service.fetchFiatPerXmrRate();
-
-        expect(mockedAxios.get).toHaveBeenCalledWith(
-            'https://coingecko.test/simple/price?ids=monero&vs_currencies=usd',
-            { timeout: 5000 }
-        );
-        expect(service.getLiveFiatPerXmr()).toBe(152.35);
-    });
-
-    it('falls back to Kraken when CoinGecko fails', async () => {
-        mockedAxios.get
-            .mockRejectedValueOnce(new Error('coingecko down'))
-            .mockResolvedValueOnce({
-                data: {
-                    error: [],
-                    result: {
-                        XMRUSD: { c: ['149.876'] }
-                    }
-                }
-            });
-
-        await service.fetchFiatPerXmrRate();
-
-        expect(warnLogSpy).toHaveBeenCalled();
-        expect(mockedAxios.get).toHaveBeenNthCalledWith(
-            2,
-            'https://kraken.test/Ticker?pair=XMRUSD',
-            { timeout: 5000 }
-        );
-        expect(service.getLiveFiatPerXmr()).toBe(149.88);
-    });
-
-    it('leaves the cached rate null when both providers fail', async () => {
-        mockedAxios.get.mockRejectedValueOnce(new Error('coingecko down')).mockRejectedValueOnce(new Error('kraken down'));
-
-        await service.fetchFiatPerXmrRate();
-
-        expect(errorLogSpy).toHaveBeenCalled();
-        expect(service.getLiveFiatPerXmr()).toBeNull();
-    });
-
-    it('falls back to Kraken when CoinGecko returns an invalid payload', async () => {
-        mockedAxios.get
-            .mockResolvedValueOnce({ data: { monero: { usd: -1 } } })
-            .mockResolvedValueOnce({
-                data: {
-                    error: [],
-                    result: {
-                        XMRUSD: { c: ['151.11'] }
-                    }
-                }
-            });
-
-        await service.fetchFiatPerXmrRate();
-
-        expect(mockedAxios.get).toHaveBeenCalledTimes(2);
-        expect(service.getLiveFiatPerXmr()).toBe(151.11);
-    });
-
-    it('keeps the previous live rate when a refresh fails after a successful fetch', async () => {
-        mockedAxios.get.mockResolvedValueOnce({
-            data: { monero: { usd: 140 } }
-        });
-        await service.fetchFiatPerXmrRate();
-
-        mockedAxios.get.mockRejectedValueOnce(new Error('coingecko down')).mockRejectedValueOnce(new Error('kraken down'));
-        await service.fetchFiatPerXmrRate();
-
-        expect(service.getLiveFiatPerXmr()).toBe(140);
-    });
-});

backend/src/modules/xmrRate/services/XmrRateService.ts

@@ -1,105 +0,0 @@
-import { Injectable, Logger, OnModuleInit } from '@nestjs/common';
-import { ConfigService } from '@nestjs/config';
-import { Cron, CronExpression } from '@nestjs/schedule';
-import { plainToInstance } from 'class-transformer';
-import { validateSync } from 'class-validator';
-import axios from 'axios';
-import Decimal from 'decimal.js';
-import type { Config } from '../../../types/Config';
-import { getErrorMessage } from '../../../utils/getErrorMessage';
-import { CoingeckoSimplePriceResponseDto } from '../dto/CoingeckoSimplePriceResponseDto';
-import { KrakenTickerResponseDto } from '../dto/KrakenTickerResponseDto';
-import { KRAKEN_XMR_PAIR_BY_FIAT } from '../krakenXmrPairs';
-
-@Injectable()
-export class XmrRateService implements OnModuleInit {
-    private readonly logger = new Logger(XmrRateService.name);
-    private fiatPerXmr: number | null = null;
-
-    constructor(private readonly configService: ConfigService) {}
-
-    async onModuleInit(): Promise<void> {
-        await this.fetchFiatPerXmrRate();
-    }
-
-    @Cron(CronExpression.EVERY_30_SECONDS)
-    async fetchFiatPerXmrRate(): Promise<void> {
-        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
-
-        try {
-            this.fiatPerXmr = await this.fetchFiatPerXmrFromCoingecko();
-        } catch {
-            this.logger.warn(`CoinGecko XMR/${shopFiatCurrency} rate fetch failed, trying Kraken`);
-
-            try {
-                this.fiatPerXmr = await this.fetchFiatPerXmrFromKraken();
-
-                this.logger.log(`Successfully fetched XMR/${shopFiatCurrency} rate from Kraken`);
-            } catch (error) {
-                this.logger.error(
-                    `Failed to fetch XMR/${shopFiatCurrency} rate from CoinGecko and Kraken: ${getErrorMessage(error)}`
-                );
-            }
-        }
-    }
-
-    getLiveFiatPerXmr(): number | null {
-        return this.fiatPerXmr;
-    }
-
-    private buildCoingeckoRateUrl(): string {
-        const { apiBaseUrl } = this.configService.get('coingecko') as Config['coingecko'];
-        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
-        const vs = shopFiatCurrency.toLowerCase();
-
-        return `${apiBaseUrl}/simple/price?ids=monero&vs_currencies=${vs}`;
-    }
-
-    private buildKrakenRateUrl(): string {
-        const { apiBaseUrl } = this.configService.get('kraken') as Config['kraken'];
-        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
-
-        const pair = KRAKEN_XMR_PAIR_BY_FIAT[shopFiatCurrency];
-
-        return `${apiBaseUrl}/Ticker?pair=${pair}`;
-    }
-
-    private async fetchFiatPerXmrFromCoingecko(): Promise<number> {
-        const { xmrRateFetchTimeoutMs } = this.configService.get('coingecko') as Config['coingecko'];
-        const { shopFiatCurrency } = this.configService.get('shopSettings') as Config['shopSettings'];
-
-        const { data } = await axios.get<unknown>(this.buildCoingeckoRateUrl(), {
-            timeout: xmrRateFetchTimeoutMs
-        });
-
-        const body = plainToInstance(CoingeckoSimplePriceResponseDto, data);
-        body.shopFiatCurrency = shopFiatCurrency;
-
-        const errors = validateSync(body);
-
-        if (errors.length > 0) {
-            throw new Error('CoinGecko response validation failed');
-        }
-
-        return new Decimal(body.monero[shopFiatCurrency.toLowerCase()]).toDecimalPlaces(2).toNumber();
-    }
-
-    private async fetchFiatPerXmrFromKraken(): Promise<number> {
-        const { xmrRateFetchTimeoutMs } = this.configService.get('kraken') as Config['kraken'];
-
-        const { data } = await axios.get<unknown>(this.buildKrakenRateUrl(), {
-            timeout: xmrRateFetchTimeoutMs
-        });
-
-        const body = plainToInstance(KrakenTickerResponseDto, data);
-        const errors = validateSync(body);
-
-        if (errors.length > 0) {
-            throw new Error('Kraken response validation failed');
-        }
-
-        const pair = Object.values(body.result)[0];
-
-        return new Decimal(pair.c[0]).toDecimalPlaces(2).toNumber();
-    }
-}