Package Exports

mongodb-memory-server

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (mongodb-memory-server) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

mongodb-memory-server

This package spins up a actual/real MongoDB Server programmatically from node for testing or mocking during development. By default it holds the data in memory. Fresh spinned up mongod process takes about 7Mb of memory. The server will allow you to connect your favorite ODM or client library to the MongoDB Server and run integration tests isolated from each other. You can start up several mongod simultaneously, it automatically discovers free ports.

This package use mongodb-prebuilt which on first start downloads the latest MongoDB binaries and save it to ~/.mongodb-prebuilt folder. So first run may take a time. All further runs will use downloaded version.

Installation

yarn add mongodb-memory-server --dev
OR
npm install mongodb-memory-server --save-dev

Usage

Simple server start:

import MongodbMemoryServer from 'mongodb-memory-server';

const mongod = new MongoMemoryServer();

const uri = await mongod.getConnectionString();
const port = await mongod.getPort();
const dbPath = await mongod.getDbPath();

mongod.stop();

Provide connection string to mongoose

import mongoose from 'mongoose';
import MongodbMemoryServer from 'mongodb-memory-server';

const mongoServer = new MongoMemoryServer();

mongoose.Promise = Promise;
mongoServer.getConnectionString().then((mongoUri) => {
  const mongooseOpts = {
    server: {
      auto_reconnect: true,
      reconnectTries: Number.MAX_VALUE,
      reconnectInterval: 1000,
    },
  };

  mongoose.connect(mongoUri, mongooseOpts);

  mongoose.connection.on('error', (e) => {
    if (e.message.code === 'ETIMEDOUT') {
      console.log(e);
      mongoose.connect(mongoUri, mongooseOpts);
    }
    console.log(e);
  });

  mongoose.connection.once('open', () => {
    console.log(`MongoDB successfully connected to ${mongoUri}`);
  });
});

For additional information I recommend you to read this article Testing a GraphQL Server using Jest with Mongoose

Several mongoose connections simultaneously

import mongoose from 'mongoose';
import MongodbMemoryServer from 'mongodb-memory-server';

mongoose.Promise = Promise;

const mongoServer1 = new MongoMemoryServer();
const mongoServer2 = new MongoMemoryServer();

const mongooseOpts = {
  server: {
    promiseLibrary = Promise;
    auto_reconnect: true,
    reconnectTries: Number.MAX_VALUE,
    reconnectInterval: 1000,
  },
};

function addEvents(connection, mongoUri) {
  connection.on('error', (e) => {
    if (e.message.code === 'ETIMEDOUT') {
      console.log(e);
      connect(mongoUri, mongooseOpts);
    }
    console.log(e);
  });

  connection.once('open', () => {
    console.log(`MongoDB successfully connected to ${mongoUri}`);
  });
}

// Firstly create connection objects, which you may import in other files and create mongoose models.
// Connection to databases will be estimated later (after model creation).
const connections = {
  conn1: mongoose.createConnection(),
  conn2: mongoose.createConnection(),
  conn3: mongoose.createConnection(),
};

mongoServer1.getConnectionString('server1_db1').then((mongoUri) => {
  connections.conn1.connect(mongoUri, mongooseOpts);
  addEvents(connections.conn1, mongoUri);
});

mongoServer1.getConnectionString('server1_db2').then((mongoUri) => {
  connections.conn2.connect(mongoUri, mongooseOpts);
  addEvents(connections.conn2, mongoUri);
});

mongoServer2.getConnectionString('server2_db').then((mongoUri) => {
  connections.conn3.connect(mongoUri, mongooseOpts);
  addEvents(connections.conn3, mongoUri);
});

export default connections;


// somewhere in other file
import { Schema } from 'mongoose';
import { conn1, conn2, conn3 } from './file_above';

const userSchema = new Schema({
  name: String,
});

const taskSchema = new Schema({
  userId: String,
  task: String,
});

export default {
  User: conn1.model('user', userSchema),
  Task: conn2.model('task', taskSchema),
  UserOnServer2: conn3.model('user', userSchema),
}

Simple Mocha test example

import mongoose from 'mongoose';
import MongodbMemoryServer from 'mongodb-memory-server';

before(function(done) {
  const mongoServer = new MongodbMemoryServer();
  mongoServer.getConnectionString().then((mongoUri) => {
    mongoose.connect(mongoUri, function(err) {
      done(err);
    });
  });
});

describe('...', function() {
    it("...", function() {
      // ...
    });
});

Credits

Inspired by alternative runners for mongodb-prebuilt:

License

MIT