feat: ✨ getUserUseCase in UsersService

libs/users/application/src/lib/users.service.spec.ts

@@ -18,13 +18,19 @@ describe('UsersService', () => {
     expect(service).toBeDefined();
   });
 
-  it('should return a user by id', () => {
-    const user: User | undefined = service.findById('1');
-    expect(user).toEqual({ id: '1', name: 'John Doe' });
+  it('should return a user by id', async () => {
+    const user = new User('1', 'John Doe');
+    jest.spyOn(service, 'findById').mockResolvedValue(user);
+
+    const result = await service.findById('1');
+    expect(result).toEqual(user);
   });
 
-  it('should return undefined if user is not found', () => {
-    const user: User | undefined = service.findById('3');
-    expect(user).toBeUndefined();
+  it('should return undefined if user is not found', async () => {
+    jest.spyOn(service, 'findById').mockResolvedValue(null);
+
+    const result = await service.findById('1');
+    expect(result).toBeNull();
+
   });
 });

libs/users/application/src/lib/users.service.ts

@@ -1,14 +1,13 @@
 import { Injectable } from '@nestjs/common';
 import { User } from '@users/domain';
 
+import { GetUserUseCase } from './use-cases/get-user.use-case';
+
 @Injectable()
 export class UsersService {
-  private users: User[] = [
-    { id: '1', name: 'John Doe' },
-    { id: '2', name: 'Richard Roe' },
-  ];
+  constructor(private readonly getUserUseCase: GetUserUseCase) {}
 
-  findById(id: string): User | undefined {
-    return this.users.find((user) => user.id === id);
+  async findById(id: string): Promise<User | null> {
+    return this.getUserUseCase.execute(id);
   }
 }

libs/users/interface-adapters/src/lib/resolver/users.resolver.spec.ts

@@ -30,40 +30,19 @@ describe('UsersResolver', () => {
   });
 
   describe('getUser', () => {
-    it('should return a user by id', () => {
-      const user: User = { id: '1', name: 'John Doe' };
-      jest.spyOn(service, 'findById').mockReturnValue(user);
+    it('should return a user by id', async () => {
+      const user = new User('1', 'John Doe');
+      jest.spyOn(service, 'findById').mockResolvedValue(user);
 
-      expect(resolver.getUser('1')).toEqual(user);
-      expect(service.findById).toHaveBeenCalledWith('1');
+      const result = await resolver.getUser('1');
+      expect(result).toEqual(user);
     });
 
-    it('should return undefined if user not found', () => {
-      jest.spyOn(service, 'findById').mockReturnValue(undefined);
+    it('should return undefined if user not found', async () => {
+      jest.spyOn(service, 'findById').mockResolvedValue(null);
 
-      expect(resolver.getUser('2')).toBeNull();
-      expect(service.findById).toHaveBeenCalledWith('2');
-    });
-  });
-
-  describe('resolveReference', () => {
-    it('should return a user by reference id', () => {
-      const user: User = { id: '1', name: 'John Doe' };
-      jest.spyOn(service, 'findById').mockReturnValue(user);
-
-      expect(
-        resolver.resolveReference({ __typename: 'User', id: '1' }),
-      ).toEqual(user);
-      expect(service.findById).toHaveBeenCalledWith('1');
-    });
-
-    it('should return undefined if user not found by reference id', () => {
-      jest.spyOn(service, 'findById').mockReturnValue(undefined);
-
-      expect(
-        resolver.resolveReference({ __typename: 'User', id: '2' }),
-      ).toBeUndefined();
-      expect(service.findById).toHaveBeenCalledWith('2');
+      const result = await resolver.getUser('1');
+      expect(result).toBeNull();
     });
   });
 });

libs/users/interface-adapters/src/lib/resolver/users.resolver.ts

@@ -9,16 +9,7 @@ export class UsersResolver {
   constructor(private usersService: UsersService) {}
 
   @Query(() => UserDto, { nullable: true })
-  getUser(@Args({ name: 'id', type: () => ID }) id: string): UserDto | null {
-    const user: User | undefined = this.usersService.findById(id); // Domain entity
-    return user ? new UserDto(user.id, user.name) : null; 
-  }
-
-  @ResolveReference()
-  resolveReference(reference: {
-    __typename: string;
-    id: string;
-  }): User | undefined {
-    return this.usersService.findById(reference.id);
+  getUser(@Args({ name: 'id', type: () => ID }) id: string): Promise<UserDto | null> {
+    return this.usersService.findById(id);
   }
 }