What is mongodb-memory-server?
The mongodb-memory-server package provides an in-memory MongoDB server for testing purposes. It allows developers to run MongoDB instances without needing to install MongoDB on their local machine, making it ideal for unit tests and CI environments.
What are mongodb-memory-server's main functionalities?
Start an in-memory MongoDB server
This code demonstrates how to start an in-memory MongoDB server using mongodb-memory-server and connect to it using Mongoose. The server runs entirely in memory, making it fast and ideal for testing.
const { MongoMemoryServer } = require('mongodb-memory-server');
const mongoose = require('mongoose');
(async () => {
const mongod = new MongoMemoryServer();
const uri = await mongod.getUri();
await mongoose.connect(uri, { useNewUrlParser: true, useUnifiedTopology: true });
console.log('MongoDB in-memory server started');
// Your code here
await mongoose.disconnect();
await mongod.stop();
})();
Use with Jest for testing
This code shows how to integrate mongodb-memory-server with Jest for testing. It sets up the in-memory MongoDB server before all tests and tears it down after all tests, ensuring a clean state for each test run.
const { MongoMemoryServer } = require('mongodb-memory-server');
const mongoose = require('mongoose');
let mongod;
beforeAll(async () => {
mongod = new MongoMemoryServer();
const uri = await mongod.getUri();
await mongoose.connect(uri, { useNewUrlParser: true, useUnifiedTopology: true });
});
afterAll(async () => {
await mongoose.disconnect();
await mongod.stop();
});
// Your tests here
Create and use collections
This code demonstrates how to create and use collections with mongodb-memory-server. It defines a Mongoose model, saves a document, and retrieves all documents from the collection.
const { MongoMemoryServer } = require('mongodb-memory-server');
const mongoose = require('mongoose');
(async () => {
const mongod = new MongoMemoryServer();
const uri = await mongod.getUri();
await mongoose.connect(uri, { useNewUrlParser: true, useUnifiedTopology: true });
const Cat = mongoose.model('Cat', { name: String });
const kitty = new Cat({ name: 'Zildjian' });
await kitty.save();
console.log('Cat saved:', kitty);
const cats = await Cat.find();
console.log('All cats:', cats);
await mongoose.disconnect();
await mongod.stop();
})();
Other packages similar to mongodb-memory-server
mockgoose
Mockgoose is a similar package that provides a mock in-memory database for MongoDB. It is designed to work with Mongoose and is useful for testing purposes. However, it is less actively maintained compared to mongodb-memory-server.
mongo-unit
Mongo-unit is another package that provides an in-memory MongoDB instance for testing. It is simpler to use but offers fewer configuration options compared to mongodb-memory-server. It is suitable for basic testing scenarios.