I would like to be able to test my Nest service against an actual database. I understand that most unit tests should use a mock object, but it also, at times, makes sense to test against the database itself.
I have searched through SO and the GH issues for Nest, and am starting to reach the transitive closure of all answers. :-)
I am trying to work from https://github.com/nestjs/nest/issues/363#issuecomment-360105413. Following is my Unit test, which uses a custom provider to pass the repository to my service class.
describe("DepartmentService", () => {
const token = getRepositoryToken(Department);
let service: DepartmentService;
let repo: Repository<Department>;
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
providers: [
DepartmentService,
{
provide: token,
useClass: Repository
}
]
}).compile();
service = module.get<DepartmentService>(DepartmentService);
repo = module.get(token);
});
Everything compiles properly, TypeScript seems happy. However, when I try to execute create
or save
on my Repository
instance, the underlying Repository
appears to be undefined. Here's the stack backtrace:
TypeError: Cannot read property 'create' of undefined
at Repository.Object.<anonymous>.Repository.create (repository/Repository.ts:99:29)
at DepartmentService.<anonymous> (relational/department/department.service.ts:46:53)
at relational/department/department.service.ts:19:71
at Object.<anonymous>.__awaiter (relational/department/department.service.ts:15:12)
at DepartmentService.addDepartment (relational/department/department.service.ts:56:16)
at Object.<anonymous> (relational/department/test/department.service.spec.ts:46:35)
at relational/department/test/department.service.spec.ts:7:71
It appears that the EntityManager
instance with the TypeORM Repository
class is not being initialized; it is the undefined
reference that this backtrace is complaining about.
How do I get the Repository
and EntityManager
to initialize properly?
thanks, tom.
To initialize typeorm properly, you should just be able to import the TypeOrmModule
in your test:
Test.createTestingModule({
imports: [
TypeOrmModule.forRoot({
type: 'mysql',
// ...
}),
TypeOrmModule.forFeature([Department])
]