Create new mongo database and user with nodejs MongoClient

README.md

How to create a previously non-existing mongo database and new user from the nodejs mongodb driver using the admin account.

1. Connect as admin user to new database, using authSource: admin (assuming adminDbName === admin)
2. Create new user

createDbAndUser.js

const { MongoClient } = require('mongodb')

/*
    Create a new database and a user for that database, when mongo is protected
    by authentication. After calling this method, you will be able to connect
    to the new database with the new user.

        mongoHost: The mongo host to connect to
        dbName: The name of the new database to create
        username: The name of the new user to create
        password: The password for the new user
        adminUser: The username of the admin user with necessary privileges
        adminPass: The password for the admin user
        adminDbName: The name of the admin database to use as authSource
*/
const createDbAndUser = ({
    mongoHost,
    dbName,
    username,
    password,
    adminUser,
    adminPass,
    adminDbName = 'admin'
} = {}) => {
    const isMissingArg =
        !mongoHost ||
        !dbName ||
        !username ||
        !password ||
        !adminUser ||
        !adminDbName

    if (isMissingArg) {
        return Promise.reject({ message: 'Missing argument' })
    }

    var client

    const newDbAdminUri = `mongodb://${adminUser}:${adminPass}@${mongoHost}/${dbName}`

    return MongoClient.connect(
                newDbAdminUri,
                { authSource: adminDbName }
            )
        .then(newDbAdminClient => {
            client = newDbAdminClient

            return Promise.resolve()
        })
        .catch(err => {
            console.error(
                `Error connecting as admin '${adminUser}' to '${dbName}'' via authSource '${adminDbName}'`
            )
            return Promise.reject(err)
        })
        .then(() => {
            return client
                .command({
                    createUser: username,
                    pwd: password,
                    roles: [{ role: 'dbOwner', db: dbName }]
                })
                .catch(err => {
                    if (
                        err &&
                        err.message &&
                        err.message.includes('already exists')
                    ) {
                        console.warn(
                            `Warning: User '${username} already exists on database '${dbName}'`
                        )
                        return Promise.resolve()
                    } else {
                        console.error(
                            `Error creating user '${username}' on database '${dbName}': ${err}`
                        )

                        client.close()
                        return Promise.reject(err)
                    }
                })
        })
        .then(() => {
            client.close()
        })
}

const test_createDbAndUser = () => {
    return createDbAndUser({
        mongoHost: 'mongo',
        dbName: 'newnewdb',
        username: 'jinyang1',
        password: 'piedpiper1',
        adminUser: 'ffdevadmin',
        adminPass: 'tCX9Qa1ZSsypp39eSeRD',
        adminDbName: 'admin'
    })
        .then(() => {
            console.log('Successfully created new DB and user')

            const newUri = 'mongodb://jinyang:piedpiper@mongo/newnewinternet'

            return MongoClient.connect(newUri)
                .then(client => {
                    console.log(
                        'Successfully connected as jinyang to newnewinternet'
                    )
                    client.close()
                })
                .catch(err => {
                    console.error(
                        'createDbAndUser successful, but failed to connect'
                    )
                    return Promise.reject(err)
                })
        })
        .catch(err => {
            console.error('Failed with error:', err)
        })
}