directus/docs/extensions/migrations.md

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A guide on how to setup your owns custom Migrations in Directus.	2 min read

Custom Migrations

Directus allows adding custom migration files that run whenever the directus database migrate:* commands are executed. All migrations must reside in the extensions/migrations folder.

File Name

The file name follows the following structure:

[identifier]-[name].js

for example:

20201202A-my-custom-migration.js

Structure

Migrations have to export an up and a down function. These functions get a Knex instance that can be used to do virtually whatever.

module.exports = {
	async up(knex) {
		await knex.schema.createTable('test', (table) => {
			table.increments();
			table.string('rijk');
		});
	},

	async down(knex) {
		await knex.schema.dropTable('test');
	},
};

::: danger Danger

Seeing that these migrations are a bit of a free-for-all, you can really harm your database. Please make sure you know what you're doing and backup your database before adding these migrations.

:::

Migrations and Directus schema

Migrations can be used to manage the contents of Directus collections (e.g. initial hydration). In order to do it, you must ensure that the schema is up to date before running your migrations.

directus database migrate:latest runs the required Directus internal migrations and the migrations from migrations directory. In general, you need the following flow:

# Option 1
npx directus bootstrap
npx directus schema apply ./path/to/snapshot.yaml

# Option 2 - without bootstrap, you must ensure that you run all required `bootstrap` tasks
npx directus database install
npx directus database migrate:latest
npx directus schema apply ./path/to/snapshot.yaml

Take notice here - to comply with this flow, migrations directory must not contain tasks that modify the contents of your Directus, because schema is not yet created when you run migrate:latest.

One way of running the contents migrations is to defer them after the schema is applied. Let's assume you store your migrations in .custom-migrations directory:

1 npx directus database install
2 npx directus database migrate:latest
3 npx directus schema apply ./path/to/snapshot.yaml
4 mv .custom-migrations/* migrations/
5 npx directus database migrate:latest

You need to install the database and run Directus migrations to prepare the Directus internals:

1 npx directus database install
2 npx directus database migrate:latest

Then, you can apply your schema:

3 npx directus schema apply ./path/to/snapshot.yaml

When the schema is ready, you can push your migrations to Directus migrations directory, and run migrate:latest again. Only your .custom-migrations will be applied in the process:

4 mv .custom-migrations/* migrations/
5 npx directus database migrate:latest