Drift

Drift is a multi-environment MongoDB migrations CLI tool for Node.js.

Installation

Globally

npm install -g drift-mongo

When installed globally, you can use the drift command as needed.

Individual project

npm install drift-mongo --save-dev

When installed in a project, you can use npx drift within the project folder structure.

Usage

You can run drift or drift --help to see the CLI commands.

Usage: drift [options] [command]

A CLI for multi-environment MongoDB migrations with Node.js

Options:
  -V, --version     output the version number
  -h, --help        display help for command

Commands:
  init              initializes drift config
  create <desc>     creates a new migration
  env <env>         adds a new environment to use
  status [options]  checks the status of migrations
  up [options]      runs all pending migrations
  down [options]    rolls back the last migration
  help [command]    display help for command

Initialization

Drift requries Node 18 (or higher) installed.

In the root of the project you'd like to setup migrations for, initialize a new drift configuration.

$ drift init

Initializing drift config...

Drift configuration generated.
Use your favorite editor to edit the config file at drift/drift.json

Running this command did two things:

1. created these folders: drift/migrations
2. created a drift.json file in the drift folder

The configuration file, drift.json, was created with a default environment: dev. Edit this file with your development environment details.

Configuration

The drift.json file maintains your drift configuration for this project, with this initial object structure:

{
  "migration_folder": "migrations",
  "envs": {
    "dev": {
      "mongo_host": "mongodb://localhost:27017",
      "mongo_db": "platform",
      "mongo_collection": "migrations"
    }
  }
}

• migration_folder: Lets you change the name/path of the migrations folder.
• envs: Holds a environment config object for each configured environment.

Note: You should add the drift.json file to your .gitignore.

Adding Environments

You can add an environment using the CLI, or by editing the drift.json file.

Usage: drift env [options] <env>

Adds a new environment to use

Options:
  -h, --help  display help for command

To add a production environment, you can use the following command:

$ drift env prod

Environment added: prod
Edit the environment at drift/drift.json

Running this command added a new object to the envs object in the drift.json configuration file.

"envs": {
  "prod": {
    "mongo_host": "mongodb://localhost:27017",
    "mongo_db": "platform",
    "mogno_collection": "migrations"
  }
}

Edit drift.json to add your connection and DB details.

Adding Migrations

Use the CLI to add a new migration to drift.

Usage: drift create [options] <desc>

Creates a new migration

Options:
  -h, --help  display help for command

To add a (test) migration, you can use the following command:

$ drift create test

Creating migration: test

Migration created!

Edit the migration at drift/migrations/1664591812475-test.js

Running this command added a new migration to the configured migrations folder (migrations by default).

Migrations

Use migration files to perform changes to your database. New migration files are created in the configured migrations folder (migrations by default):

export const up = async (db, client) => {
  // Migration code goes here
}
export const down = async (db, client) => {
  // Rollback code goes here
}

Edit this file with your migration code. The db object is the official MongoDB object, the client object is a MongoClient instance.

Migrations use async-await and your migration code must use async-await and return a promise.

Example

export const up = async (db, client) => {
  await db.collection('test').insertOne({test: 'test'})
}
export const down = async (db, client) => {
  await db.collection('test').deleteOne({test: 'test'})
}

Migrating up

Run all pending migrations on a given environment. If no environment is specified, dev is configured as default.

Usage: drift up [options]

runs all pending migrations

Options:
  -e --env <environment>  environment to run migrations for (default: dev) (default: "dev")
  -h, --help              display help for command

To run all pending migrations for the dev (default) environment use the following command:

$ drift up

Migrated: 1664591812475-test.js

Migrations complete!

To run all pending migrations for the prod environment, use the following command:

$ drift up --env prod

Migrated: 1664591812475-test.js

Migrations complete!

Any error caught will stop the process.

Migrating down

When you need to revert migrations for a given environment, migrating down will revert back through the completed migrations one at a time.

Usage: drift down [options]

rolls back the last migration

Options:
  -e --env <environment>  environment to run migrations for (default: dev) (default: "dev")
  -h, --help              display help for command

To revert the last completed migration for the dev (default) environment use the following command:

$ drift down

Downgraded: 1664591812475-test.js

Rollback complete!

To rever the last completed migration for the prod environment, use the following command:

$ drift down --env prod

Downgraded: 1664591812475-test.js

Migrations complete!

Migration status

Easily check the status of the migrations for a given environment.

Usage: drift status [options]

checks the status of migrations

Options:
  -e --env <environment>  environment to check status for (default: dev) (default: "dev")
  -h, --help              display help for command

To check the status of migrations for the dev (default) environment, use the following command:

$ drift status

Migration Status
Environment: dev

┌─────────────────────────┬──────────┬───────────────────────┐
│ Filename                │ Status   │ Ran On                │
├─────────────────────────┼──────────┼───────────────────────┤
│ 1664591812475-test.js   │ migrated │ 9/30/2022, 2:07:06 PM │
└─────────────────────────┴──────────┴───────────────────────┘