feat(medusa): Emit "discount.created" event when discount is created (#5816)

.changeset/twelve-parents-occur.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/medusa": patch
+---
+
+Emit event when discount is created

packages/medusa/src/services/__tests__/discount.js

@@ -7,6 +7,13 @@ import { In } from "typeorm"
 
 const featureFlagRouter = new FlagRouter({})
 
+const eventBusService = {
+  emit: jest.fn(),
+  withTransaction: function () {
+    return this
+  },
+}
+
 describe("DiscountService", () => {
   describe("create", () => {
     const discountRepository = MockRepository({})
@@ -29,6 +36,7 @@ describe("DiscountService", () => {
       discountRuleRepository,
       regionService,
       featureFlagRouter,
+      eventBusService
     })
 
     beforeEach(() => {
@@ -99,6 +107,8 @@ describe("DiscountService", () => {
       })
 
       expect(discountRepository.save).toHaveBeenCalledTimes(1)
+      expect(eventBusService.emit).toHaveBeenCalledTimes(1)
+      expect(eventBusService.emit).toHaveBeenCalledWith(DiscountService.Events.CREATED, {id: undefined})
     })
 
     it("successfully creates discount with start and end dates", async () => {

packages/medusa/src/services/discount.ts

@@ -54,6 +54,9 @@ import EventBusService from "./event-bus"
  * @implements {BaseService}
  */
 class DiscountService extends TransactionBaseService {
+  static readonly Events = {
+    CREATED: "discount.created",
+  }
   protected readonly discountRepository_: typeof DiscountRepository
   protected readonly customerService_: CustomerService
   protected readonly discountRuleRepository_: typeof DiscountRuleRepository
@@ -231,6 +234,10 @@ class DiscountService extends TransactionBaseService {
         )
       }
 
+      await this.eventBus_
+          .withTransaction(manager)
+          .emit(DiscountService.Events.CREATED, { id: result.id })
+
       return result
     })
   }