mongo-memory.js

const { MongoMemoryServer } = require('mongodb-memory-server');
console.log(MongoMemoryServer)
const mongod = new MongoMemoryServer();
const x = async() => {
    const uri = await mongod.getConnectionString();
    const port = await mongod.getPort();
    const dbPath = await mongod.getDbPath();
    const dbName = await mongod.getDbName();
    // some code
//   ... where you may use `uri` for as a connection string for mongodb or mongoose

// you may check instance status, after you got `uri` it must be `true`
    console.log(uri); // return Object with instance data

// you may stop mongod manually
//     await mongod.stop();

// when mongod killed, it's running status should be `false`
    mongod.getInstanceInfo();

}
x()