Hello, I am new to Javascript and develop an API-Rest with Nodejs, Express and Mongodb. While testing, I use Jest, Supertest, Factory Girl, Faker, and another instance of Mongodb in Docker, so I do not mock my database. My S.O. is Ubuntu.

I'm having trouble completing the integration tests because I believe the bank data will be erased before each test.

Whenever I run a test suite, everything happens normally.

However, if I run all the test-suites concurrently, random errors will occur with respect to the data in the database.

In this expression, the error was related to UserController.js, but sometimes errors occur in other controllers, and errors and files occur at random.

I think it might have something to do with my database cleanup feature, it's an asynchronous function, and it seems to me that these errors occur because it takes a long time to run and clean up the database when you run a new test. which eventually invalidates the ongoing test.

This is my jest setup file:

import '../src/bootstrap';

import databaseHelper from '../src/app/helpers/database';

beforeAll(() => {
  return databaseHelper.connect();
});

beforeEach(() => {
  return databaseHelper.truncate();
});

afterAll(() => {
  return databaseHelper.disconnect();
});

This is my database help:

import mongoose from 'mongoose';

import databaseConfig from '../../config/database';

const connect = async () => {
  if (mongoose.connection.readyState === 0) {
    await mongoose.connect(databaseConfig.uri, databaseConfig.options);
  }
};

const truncate = async () => {
  const models = mongoose.connection.modelNames();
  const promises = models.map(async model =>
    mongoose.connection.model(model).deleteMany({})
  );
  await Promise.all(promises);
};

const disconnect = async () => {
  await mongoose.disconnect();
};

export default {
  connect,
  truncate,
  disconnect,
};

My database settings:

export default {
  uri: process.env.DB_URL,
  options: {
    useCreateIndex: true,
    useNewUrlParser: true,
    useFindAndModify: false,
  },
};

In almost all my tests, I create a database record with Factory Girl and Faker and use Supertest to make a request and analyze the answer, as in the following example:

it('should not be able to create user with duplicate email', async done => {
    const user = await factory.build('User');

    let response = await request.post('/users').send({
      name: user.name,
      email: user.email,
      password: user.password,
    });

    expect(response.status).toBe(200);
    expect(response.body).toHaveProperty('id');
    expect(response.body).toHaveProperty('name', user.name);
    expect(response.body).toHaveProperty('email', user.email);

    response = await request.post('/users').send({
      name: user.name,
      email: user.email,
      password: user.password,
    });

    expect(response.status).toBe(400);
    expect(response.body).toHaveProperty('error', 'User already exists');

    done();
  });

This is the Factory Girl configuration:

import faker from 'faker';
import { factory, MongooseAdapter } from 'factory-girl';

import User from '../src/app/models/User';
import Habit from '../src/app/models/Habit';

const adapter = new MongooseAdapter();

factory.setAdapter(adapter);

factory.define('User', User, {
  name: faker.name.findName(),
  email: faker.internet.email(),
  password: faker.internet.password(),
});

factory.define('Habit', Habit, {
  name: faker.lorem.word(),
  description: faker.lorem.sentence(),
});

export default factory;

These are my dependencies:

  "dependencies": {
    "bcryptjs": "^2.4.3",
    "dotenv": "^8.1.0",
    "express": "^4.17.1",
    "joi": "^14.3.1",
    "jsonwebtoken": "^8.5.1",
    "mongoose": "^5.6.11",
    "mongoose-paginate": "^5.0.3"
  },
  "devDependencies": {
    "@sucrase/jest-plugin": "^2.0.0",
    "@types/jest": "^24.0.18",
    "eslint": "^6.3.0",
    "eslint-config-airbnb-base": "^14.0.0",
    "eslint-config-prettier": "^6.1.0",
    "eslint-plugin-import": "^2.18.2",
    "eslint-plugin-prettier": "^3.1.0",
    "factory-girl": "^5.0.4",
    "faker": "^4.1.0",
    "jest": "^24.9.0",
    "nodemon": "^1.19.1",
    "prettier": "^1.18.2",
    "sucrase": "^3.10.1",
    "supertest": "^4.0.2"
  }

The full code is on github: https://github.com/dyarleniber/habit-tracker-back-end

Can someone please tell me what I did wrong? Or give me suggestions for improvement?

Another interesting point was that after running the tests multiple times, I noticed many processes running on my computer with the following commands:

USER 999 COMANDO mongodb --bind_ip_all

USER  COMANDO node_modulesjest-wo