NestJS Mock RabbitMQ in Jest - jestjs

Question

I have an AppModule file as follows:
import { Module } from '#nestjs/common'
import { RabbitMQModule } from '#golevelup/nestjs-rabbitmq'
#Module({
imports: [
RabbitMQModule.forRoot(RabbitMQModule, {
exchanges: [
{
name: 'my_rabbit',
type: 'direct',
},
],
uri: process.env.RABBITMQ_URI,
connectionInitOptions: { wait: true },
}),
],
})
export class AppModule {}
I have tried to mock rabbitmq using #golevelup/nestjs-rabbitmq like this:
import { Module } from '#nestjs/common'
import { RabbitMQModule } from '#golevelup/nestjs-rabbitmq'
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
imports: [
AppModule
],
})
.overrideProvider(AmqpConnection)
.useValue(createMock<AmqpConnection>())
.compile()
})
This is giving me error:
[Nest] 2745 - 24/07/2022, 17:02:54 ERROR [AmqpConnection] Disconnected from RabbitMQ broker (default)
Error: connect ECONNREFUSED 127.0.0.1:5672
If i mock the whole rabbitmq module like:
jest.mock('#golevelup/nestjs-rabbitmq')
I will get errors like:
Nest cannot create the AppModule instance.
The module at index [0] of the AppModule "imports" array is undefined.
Has anyone successfully mocked RabbitMQ? Please assist if possible.

Answer 1

I solve this problem mocking an AmqpConnection like this.
import { AmqpConnection } from "#nestjs-plus/rabbitmq";
import { TestingModule, Test } from "#nestjs/testing";
import { IntegrationQueueService } from "./integration-queue.service";
describe('IntegrationQueueService', () => {
type MockType<T> = {
[P in keyof T]?: jest.Mock<{}>;
};
const mockFactory: () => MockType<AmqpConnection> = jest.fn(() => ({
publish: jest.fn(() => AmqpConnection),
}))
let service: IntegrationQueueService;
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
providers: [
IntegrationQueueService,
{
provide: AmqpConnection,
useFactory: mockFactory,
},
],
})
.compile();
service = module.get<IntegrationQueueService> (IntegrationQueueService);
});
it('should be defined', () => {
expect(service).toBeDefined();
});
})