generate code

src/modules/coupons/controllers/coupon.controller.ts

@@ -95,5 +95,10 @@ export class CouponController {
       validateCouponDto.userId,
     );
   }
-}
 
+  @Get('public/coupons/generate-code')
+  @ApiOperation({ summary: 'generate a coupon code' })
+  generateCouponCode(@RestId() restId: string) {
+    return this.couponService.generateCouponCode(restId);
+  }
+}

src/modules/coupons/entities/coupon.entity.ts

@@ -1,4 +1,4 @@
-import { Entity, ManyToOne, Property, Enum } from '@mikro-orm/core';
+import { Entity, ManyToOne, Property, Enum, Unique } from '@mikro-orm/core';
 import { BaseEntity } from '../../../common/entities/base.entity';
 import { Restaurant } from '../../restaurants/entities/restaurant.entity';
 
@@ -8,11 +8,12 @@ export enum CouponType {
 }
 
 @Entity({ tableName: 'coupons' })
+@Unique({ properties: ['code', 'restaurant'] })
 export class Coupon extends BaseEntity {
   @ManyToOne(() => Restaurant)
   restaurant!: Restaurant;
 
-  @Property({ unique: true })
+  @Property()
   code!: string;
 
   @Property()

src/modules/coupons/providers/coupon.service.ts

@@ -8,6 +8,7 @@ import { EntityManager } from '@mikro-orm/postgresql';
 import { RequiredEntityData } from '@mikro-orm/core';
 import { Coupon, CouponType } from '../entities/coupon.entity';
 import { CouponMessage, RestMessage } from 'src/common/enums/message.enum';
+import { randomBytes } from 'node:crypto';
 
 @Injectable()
 export class CouponService {
@@ -250,4 +251,13 @@ export class CouponService {
       await this.em.persistAndFlush(coupon);
     }
   }
+
+  async generateCouponCode(restId: string): Promise<string> {
+    const code = randomBytes(8).toString('hex');
+    const existingCoupon = await this.couponRepository.findOne({ code, restaurant: { id: restId } });
+    if (existingCoupon) {
+      return this.generateCouponCode(restId);
+    }
+    return code;
+  }
 }