feat(nestjs): migrate to NestJS

packages/server/src/modules/Customers/commands/EditOpeningBalanceCustomer.service.ts

@@ -0,0 +1,74 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { Knex } from 'knex';
+import {
+  ICustomerOpeningBalanceEditDTO,
+  ICustomerOpeningBalanceEditedPayload,
+  ICustomerOpeningBalanceEditingPayload,
+} from '../types/Customers.types';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { UnitOfWork } from '@/modules/Tenancy/TenancyDB/UnitOfWork.service';
+import { Customer } from '../models/Customer';
+import { events } from '@/common/events/events';
+import { TenantModelProxy } from '@/modules/System/models/TenantBaseModel';
+
+@Injectable()
+export class EditOpeningBalanceCustomer {
+  /**
+   * @param {EventEmitter2} eventPublisher - Event emitter service.
+   * @param {UnitOfWork} uow - Unit of work service.
+   * @param {typeof Customer} customerModel - Customer model.
+   */
+  constructor(
+    private eventPublisher: EventEmitter2,
+    private uow: UnitOfWork,
+
+    @Inject(Customer.name)
+    private customerModel: TenantModelProxy<typeof Customer>,
+  ) {}
+
+  /**
+   * Changes the opening balance of the given customer.
+   * @param {number} customerId - Customer ID.
+   * @param {ICustomerOpeningBalanceEditDTO} openingBalanceEditDTO
+   */
+  public async changeOpeningBalance(
+    customerId: number,
+    openingBalanceEditDTO: ICustomerOpeningBalanceEditDTO,
+  ): Promise<Customer> {
+    // Retrieves the old customer or throw not found error.
+    const oldCustomer = await this.customerModel()
+      .query()
+      .findById(customerId)
+      .throwIfNotFound();
+
+    // Mutates the customer opening balance under unit-of-work.
+    return this.uow.withTransaction(async (trx: Knex.Transaction) => {
+      // Triggers `onCustomerOpeningBalanceChanging` event.
+      await this.eventPublisher.emitAsync(
+        events.customers.onOpeningBalanceChanging,
+        {
+          oldCustomer,
+          openingBalanceEditDTO,
+          trx,
+        } as ICustomerOpeningBalanceEditingPayload,
+      );
+      // Mutates the customer on the storage.
+      const customer = await this.customerModel()
+        .query()
+        .patchAndFetchById(customerId, {
+          ...openingBalanceEditDTO,
+        });
+      // Triggers `onCustomerOpeingBalanceChanged` event.
+      await this.eventPublisher.emitAsync(
+        events.customers.onOpeningBalanceChanged,
+        {
+          customer,
+          oldCustomer,
+          openingBalanceEditDTO,
+          trx,
+        } as ICustomerOpeningBalanceEditedPayload,
+      );
+      return customer;
+    });
+  }
+}