In-memory MongoDB for test?

Question

I am writing some integration and system tests for my NodeJS application using a MongoDB database. The test framework I use is Mocha and Supertest. Is it possible to setup Mongo

Answer 1

I recommend using mongodb-memory-server.

I have a DB file that is shared over the whole project, so I have to have it testable as well.

//db.js

import mongoose from 'mongoose';
import bluebird from 'bluebird';

module.exports = {
  mongoose,
  init: () => {
      mongoose.Promise = bluebird;
  },
  connect: async database => {
      try {
          const conn =  await mongoose.connect(
              database,
              { useNewUrlParser: true }
          );

          //eslint-disable-next-line
          console.log(`MongoDb Connected on: ${database}`);

          return conn;
      } catch (err) {
          //eslint-disable-next-line
          console.log('Error to connect on mongo', err);
      }
  },
  disconnect: async () => await mongoose.connection.close()
};

To be used (db.js) on my tests I've created a test-helper.js file.

'use strict';
import MongodbMemoryServer from 'mongodb-memory-server';
import db from '../src/db';

const server = new MongodbMemoryServer();

const createDB = async () => {
    try {
       const url = await server.getConnectionString();
       db.connect(url);
    } catch (err) {
      throw err;
    }
 };

 const destroyDB = () => {
   db.disconnect();

 };

 module.exports = {
    createDB,
    destroyDB
 }; 
}

So, my tests always have before and after (to create and destroy de DB), something like:

import { createDB, destroyDB } from '../test-helper';
before(() => {
  createDB();
});
after(() => {
  destroyDB();
});

Hope it is helpful.

The project I'm using it: https://github.com/abdalla/node-auth