seandgrimes / database-migrator

Database Migrator

This is a project that allows you to define migrations for multiple database engines and then tie these migrations to a certain version. The idea is that for applications that use polyglot data that you can define all migrations within a single Node package, then migrate to a particular version from the command line across all database engines used by the application. Each migration that has been added will run in order based on its timestamp, and any migrations for previous versions than the one being migrated to will be ran as needed.

Usage

import {DatabaseEngine, Migrate, MongoDbMigrate, Neo4JMigrate} from 'database-migrator';
import {Db} from 'mongodb';
import {Session} from 'neo4j-driver';

@Migrate("1.0.0", "201710241151", DatabaseEngine.MongoDB)
export class Migration201710241151_AddPropertyToDocument implements MongoDbMigrate {
    migrate(mongodb : Db) {
        mongodb.collections("documents").update({
            "$set": {
                "property": null
            }
        });
    }
}

@Migrate("1.0.0", "201710241222", DatabaseEngine.Neo4J)
export class Migration201710241222_AddPropertyToDocument implements Neo4JMigrate {
    async migrate(session : Session) {
        await session.run(
            `MATCH (d:Document)
            SET d.property = null
            RETURN d`
        );
    }
}

Adding new migrations

There will be a global command installed named database-migrator that you will be able to use to generate new migrations. Basic usage is as follows:

database-generator --add-migration --database-engine=mongodb --version=1.0.0 --name=AddProperty --output=src/migrations