bridge-node-mongo-migration

A Node.JS Promised based library intends to provide a migration framework based on MongoDb.

TODO

• [] Test with mongodb replicasSet management

How it works

This library manage the following cases:

• Do not run already run migrations (based on mongoDb store)
• Alert on altered already run migrations
• Locking feature while processing (based on mongoDb store)
• Rollback management (Up/Down)
• Conditional migration on custom condition

Migration Process

• Acquire the lock (if not just do nothing)
• List all migrations in the migration folder (order based on natural file sort)
• Filter Not Runnable migrations (custom condition filtering)
• Filter already run migrations
• Run sequentially all pending migrations
• If an error occurred while running a migration rollback all newly run migrations (including the failed migration)

Installation

npm i bridge-node-mongo-migration

Usage

This library is a Promise based library

Import this package import {Configuration, Runner} from 'bridge-node-mongo-migration';

You need to provide a configuration.

The configuration Object needs the following keys :

• mongo : Global mongo client configuration
  • url : Mongo connection URI string (http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html)
  • database : Mongo database to use
  • clientOptions: Mongo client options. See Official mongo documentation for futher details
• [optional] migrationCollectionName: The name of the MongoDB collection to track already ran migrations, default to _migrations
• [optional] lockingCollectionName: The name of the MongoDB collection used during migration process, default to _migration_lock
• [optional] log: Custom logging function with this signature (level: string, message: string, payload: any) => void, default none

Create your configuration

Then, instantiate migration runner : const runner = new Runner(config, <directory to scan>);

The second parameter is the directory that store your migrations scripts (relative to your working directory)

Define your migrations.

Each migrations must be defined in a specific folder (according to your configuration object).

You must define ONE file per migration. This file should :

• Respect the following naming convention : {orderNumber}_{name} which is resolved by the following regex
• Export a default class that extends the Migration base class Available with import {Migration} from 'bridge-node-mongo-migration';

A migration could be ignored on custom condition, to achieve that you need to override isRunnable(db: Db): Promise<boolean> migration method.

A migration could be run each times you start a migration process (useful for seeds). To achieve this you need to override alwaysRun(db: Db): Promise<boolean> method on your Migration class.

And finally run the migration process with : runner.executePendingMigrations();