Migration Library

A very simple and small library to speed up the migration process to your MongoDB and others routines. A fully updated microservice version.

• Project licensed under: GPLv3
• Site Documentation: Homepage
• Repository: GitHub

TODO List

1. Add a new collection to check via semver if APP_VERSION is newer or older;
2. Create the down systems;
3. Implement migrations for Sequelize ORM;

Environment Variables

This services use some environment variables to pre-adjust some things, like:

• MONGO_URL: A URI for connect to a mongo database. Default: mongodb://root:[email protected]/platform?authSource=admin
• MONGO_DATABASE: a database name (usually, same as in MONGO_URL). Default: platform.
• MIGRATION_COLLECTION_NAME: the collection name to maintain documents about stages and results. Default: migration.
• MIGRATION_DEBUG_CONSOLE: show in console some debug messages about locker process.
• APP_VERSION: use this to inform the software version (usually it is a docker environment variable). Default: 1.0.0.

Migration Files

All migration files need to use a specific pattern, starting with numbers and a _. My recommendation is to use date and _ plus description. Examples:

00_fixture.ts
20200910_ChangingUserProfile.ts
20200910_DefaultRBAC.ts

Template

import { MigrationParameters, LogLevel } from '@nsfilho/migration';

/** Used to show during logs and inform what about this migration is. */
export const description = 'Sample migration';

export const up = async ({ db, collections, log, refresh }: MigrationParameters): Promise<void> => {
    // sample 1: find a registry in a collection and forEach
    const content = await collections.migration.find();
    content.forEach((v) => {
        log({ message: `Record: ${JSON.stringify(v, null, 4)}`, level: LogLevel.normal });
    });

    // sample 2: inserting a registry in a non-existing collection
    const collectionSample1 = await db.collection('sample1');
    collectionSample1.insertOne({
        field1: 'hello',
        field2: 'word',
    });

    // Re-create the collections object.
    await refresh();

    // sample 3: inserting in a existing collection
    await collections.oldSample1.insertOne({
        field1: 'yes',
        field2: 'I can',
    });
};

export const down = async ({ collections }: MigrationParameters): Promise<void> => {
    // a piece of code for down (not implemented yet!)
};

Resume the API

• collections: a Javascript/Typescript object with collections as properties name.
• log: is a function that will log all records inside the migration collection, in a document what registry state executing file.

Example

import { join } from 'path';
import { lockResource } from '@nsfilho/redis-locker';
import { startMigration } from '@nsfilho/migration';

/** Locking a resource for all instances of this software */
lockResource({
    resourceName: __filename,
    callback: startMigration({
        migrationPath: join(__dirname, 'migrations'),
    }),
});