refactor: currencies service.

refactor: exchange rates service.

server/src/services/Currencies/CurrenciesService.ts

@@ -0,0 +1,152 @@
+import { Inject, Container, Service } from 'typedi';
+import {
+  ICurrencyEditDTO,
+  ICurrencyDTO,
+  ICurrenciesService,
+  ICurrency
+} from 'interfaces';
+import {
+  EventDispatcher,
+  EventDispatcherInterface,
+} from 'decorators/eventDispatcher';
+import { ServiceError } from 'exceptions';
+import TenancyService from 'services/Tenancy/TenancyService';
+
+const ERRORS = {
+  CURRENCY_NOT_FOUND: 'currency_not_found',
+  CURRENCY_CODE_EXISTS: 'currency_code_exists'
+};
+
+@Service()
+export default class CurrenciesService implements ICurrenciesService {
+  @Inject('logger')
+  logger: any;
+
+  @EventDispatcher()
+  eventDispatcher: EventDispatcherInterface;
+
+  @Inject()
+  tenancy: TenancyService;
+
+  /**
+   * Retrieve currency by given currency code or throw not found error.
+   * @param {number} tenantId 
+   * @param {string} currencyCode 
+   * @param {number} currencyId 
+   */
+  private async validateCurrencyCodeUniquiness(tenantId: number, currencyCode: string, currencyId?: number) {
+    const { Currency } = this.tenancy.models(tenantId);
+
+    this.logger.info('[currencies] trying to validate currency code existance.', { tenantId, currencyCode });
+    const foundCurrency = await Currency.query().onBuild((query) => {
+      query.findOne('currency_code', currencyCode);
+
+      if (currencyId) {
+        query.whereNot('id', currencyId)
+      }
+    });
+    if (foundCurrency) {
+      this.logger.info('[currencies] the currency code already exists.', { tenantId, currencyCode });
+      throw new ServiceError(ERRORS.CURRENCY_CODE_EXISTS);
+    }
+  }
+
+  /**
+   * Retrieve currency by the given currency code or throw service error.
+   * @param {number} tenantId 
+   * @param {string} currencyCode 
+   */
+  private async getCurrencyByCodeOrThrowError(tenantId: number, currencyCode: string) {
+    const { Currency } = this.tenancy.models(tenantId);
+
+    this.logger.info('[currencies] trying to validate currency code existance.', { tenantId, currencyCode });
+    const foundCurrency = await Currency.query().findOne('currency_code', currencyCode);
+
+    if (!foundCurrency) {
+      this.logger.info('[currencies] the given currency code not exists.', { tenantId, currencyCode });
+      throw new ServiceError(ERRORS.CURRENCY_NOT_FOUND);
+    }
+    return foundCurrency;
+  }
+
+  /**
+   * Retrieve currency by given id or throw not found error.
+   * @param {number} tenantId 
+   * @param {number} currencyId 
+   */
+  private async getCurrencyIdOrThrowError(tenantId: number, currencyId: number) {
+    const { Currency } = this.tenancy.models(tenantId);
+
+    this.logger.info('[currencies] trying to validate currency by id existance.', { tenantId, currencyId });
+    const foundCurrency = await Currency.query().findOne('id', currencyId);
+
+    if (!foundCurrency) {
+      this.logger.info('[currencies] the currency code not found.', { tenantId, currencyId });
+      throw new ServiceError(ERRORS.CURRENCY_NOT_FOUND);
+    }
+    return foundCurrency;
+  }
+
+  /**
+   * Creates a new currency.
+   * @param {number} tenantId 
+   * @param {ICurrencyDTO} currencyDTO 
+   */
+  public async newCurrency(tenantId: number, currencyDTO: ICurrencyDTO) {
+    const { Currency } = this.tenancy.models(tenantId);
+    this.logger.info('[currencies] try to insert new currency.', { tenantId, currencyDTO });
+
+    await this.validateCurrencyCodeUniquiness(tenantId, currencyDTO.currencyCode);
+
+    await Currency.query().insert({ ...currencyDTO });
+    this.logger.info('[currencies] the currency inserted successfully.', { tenantId, currencyDTO });
+  }
+
+  /**
+   * Edit details of the given currency.
+   * @param {number} tenantId 
+   * @param {number} currencyId 
+   * @param {ICurrencyDTO} currencyDTO 
+   */
+  public async editCurrency(tenantId: number, currencyId: number, currencyDTO: ICurrencyEditDTO): Promise<ICurrency> {
+    const { Currency } = this.tenancy.models(tenantId);
+
+    this.logger.info('[currencies] try to edit currency.', { tenantId, currencyId, currencyDTO });
+    await this.getCurrencyIdOrThrowError(tenantId, currencyId);
+
+    const currency = await Currency.query().patchAndFetchById(currencyId, { ...currencyDTO });
+    this.logger.info('[currencies] the currency edited successfully.', { tenantId, currencyDTO });
+
+    return currency;
+  }
+
+  /**
+   * Delete the given currency code.
+   * @param {number} tenantId 
+   * @param {string} currencyCode 
+   * @return {Promise<}
+   */
+  public async deleteCurrency(tenantId: number, currencyCode: string): Promise<void> {
+    const { Currency } = this.tenancy.models(tenantId);
+    this.logger.info('[currencies] trying to delete the given currency.', { tenantId, currencyCode });
+
+    await this.getCurrencyByCodeOrThrowError(tenantId, currencyCode);
+    
+    await Currency.query().where('currency_code', currencyCode).delete();
+    this.logger.info('[currencies] the currency deleted successfully.', { tenantId, currencyCode });
+  }
+
+  /**
+   * Listing currencies.
+   * @param {number} tenantId 
+   * @return {Promise<ICurrency[]>}
+   */
+  public async listCurrencies(tenantId: number): Promise<ICurrency[]> {
+    const { Currency } = this.tenancy.models(tenantId);
+
+    const currencies = await Currency.query().onBuild((query) => {
+      query.orderBy('createdAt', 'ASC');
+    });
+    return currencies;
+  }
+}