ESM & sequelize db:migrate

[mahnunchik]

It would be great if sequelize-cli supports migrations in ESM way.

What you are doing?

// db/migrations/20220924162319-create-test.js
export async function up(queryInterface, Sequelize) {
  await queryInterface.createTable('test', {
    id: {
      type: Sequelize.DataTypes.INTEGER,
      allowNull: false,
      autoIncrement: true,
      primaryKey: true,
    },
    createdAt: {
      allowNull: false,
      type: Sequelize.DataTypes.DATE,
    },
    updatedAt: {
      allowNull: false,
      type: Sequelize.DataTypes.DATE,
    }
  });
}
export function down(queryInterface, Sequelize) {
  return queryInterface.dropTable('test');
}

npx sequelize db:migrate

What do you expect to happen?

Migration works.

What is actually happening?

npx sequelize db:migrate

Sequelize CLI [Node: 16.16.0, CLI: 6.4.1, ORM: 6.23.0]

Loaded configuration file "db/config.js".
== 20220924162319-create-test: migrating =======

ERROR: require() of ES Module /test/db/migrations/20220924162319-create-test.js from /test/node_modules/umzug/lib/migration.js not supported.
Instead change the require of 20220924162319-create-test.js in /test/node_modules/umzug/lib/migration.js to a dynamic import() which is available in all CommonJS modules.

Output, either JSON or SQL

Dialect: postgres
Database version: 12
Sequelize CLI version: 6.4.1
Sequelize version: 6.23.0

[mahnunchik]

Related issue sequelize/umzug#475

[bobber205]

Amazing how we hit this issue at the exact same time yesterday!

[mahnunchik]

Replacing:
return require(this.path);
with
return import(this.path);
solves it for ES Modules.

Monkey patch from the original issue works...

[bobber205]

@mahnunchik Where did you do this change set?

[mahnunchik]

@bobber205 sequelize-cli uses pretty old 2.3.0 umzug module:

https://github.com/sequelize/umzug/blob/v2.3.0/src/migration.js#L68

[WikiRik]

sequelize-cli uses pretty old 2.3.0 umzug module:

https://github.com/sequelize/umzug/blob/v2.3.0/src/migration.js#L68

Indeed. We will update to the latest umzug release in v7 of the CLI.

[1valdis]

As a temporary workaround to not have to rename generated migration files to .cjs, in your migrations folder, create a package.json file with contents

{
  "type": "commonjs"
}

or, since commonjs is the default, simply

{}

This tricks Node into thinking that your migration folder is a commonjs package, and allows you to use `npx sequelize migration:create` and `npx sequelize db:migrate` the same way as you'd use it in a commonjs project.

[taslangraham]

sequelize-cli uses pretty old 2.3.0 umzug module:
https://github.com/sequelize/umzug/blob/v2.3.0/src/migration.js#L68

Indeed. We will update to the latest umzug release in v7 of the CLI.

Hey @WikiRik, can you provide an expected timeline for when v7 will be released?

[WikiRik]

@taslangraham not yet, we'll start work when sequelize v7 is in beta (which we expect in the next month or so)

[taslangraham]

@WikiRik thanks for the update!

[mariusa]

Does this provide a solution? #982
If so, how would an ESM .sequelizerc look?

There's also this docs change, but it doesn't mention .sequelizerc sequelize/sequelize@8153444

[SmashingQuasar]

It's been over 9 months that this issue is going on now.
Not supporting ESM is a real deal-breaker for many people as ESM is superior to CJS in many ways that are now common knowledge.
If you need help migrating to a newer version of umzug I would be happy to help by opening a PR.
umzug 2.3.0 is now over 3 years old, it's most likely no longer being maintained. It's becoming critical to update this dependency.

In any case, just let me know if you need a PR to move to ESM-first with a secondary CJS build. I would be happy to help if this can fast-track this problem for everyone.

[WikiRik]

We're currently planning a full rewrite from scratch of the CLI for v7, but we're happy to review PRs to upgrade umzug and allow ESM builds if it does not have any breaking changes

[SmashingQuasar]

We're currently planning a full rewrite from scratch of the CLI for v7, but we're happy to review PRs to upgrade umzug and allow ESM builds if it does not have any breaking changes

I understand that, you mentioned it on January 3rd. The thing is, it's not tied to the CLI, so the full rewrite will not solve the issue.
The problem lies within umzug itself. Even in it's current state, it is still written and built using CJS. Since umzug is using a dynamic require, a rewrite of umzug is necessary.
Unfortunately, this issue is affecting more thant Sequelize. Several ORMs are using umzug and reporting the same problem. It's relatively widespread.
Since Sequelize seems to also be maintaining umzug, would you be open to a PR migrating it to ESM-first?