Sequelize - run migration with es6 and modules

Question

I'm not sure if I'm doing something wrong or what. I feel like I'm running a modern, fairly common stack. But I cannot get the new Sequelize v6 to work nicely with my setup. I am on Node v14.17, Sequelize v6.6.2 and in my package.json I have "type": "module". I finally figured out how to get my models automatically imported with a lot of googling and tinkering. So now I am trying to add a field to a model using the migration tool. I created the migration file in the migrations folder.
That looks like this:

'use strict';

module.exports = {
    up: async (queryInterface, Sequelize) => {
        /**
         * Add altering commands here.
         *
         * Example:
         * await queryInterface.createTable('users', { id: Sequelize.INTEGER });
         */
        return Promise.all([
            queryInterface.addColumn(
                'Customers', // table name
                'include_core_items', // new field name
                {
                    type: Sequelize.Boolean,
                    allowNull: false,
                    defaultValue: true,
                    after: 'customer_name',
                }
            ),
        ]);
    },

    down: async (queryInterface, Sequelize) => {
        /**
         * Add reverting commands here.
         *
         * Example:
         * await queryInterface.dropTable('users');
         */
        return Promise.all([
            queryInterface.removeColumn('Customers', 'include_core_items'),
        ]);
    },
};

And then I am trying to run the migration with: npx sequelize-cli db:migrate and I get the following errors: ERROR: Error reading "config\config.js". Error: Error [ERR_REQUIRE_ESM]: Must use import to load ES Module: C:\...\config\config.js require() of ES modules is not supported. require() of C:\...\config\config.js from C:\Users\...\AppData\Roaming\npm-cache\_npx\12576\node_modules\sequelize-cli\lib\helpers\config-helper.js is an ES module file as it is a .js file whose nearest pare nt package.json contains "type": "module" which defines all .js files in that package scope as ES modules. Instead rename config.js to end in .cjs, change the requiring code to use import(), or remove "type": "module" from C:\...\package.json.

I have tried renaming the config to .cjs and then get the error: ERROR: Dialect needs to be explicitly supplied as of v4.0.0 so I don't think it is correctly reading in the ENV variables or something.

config.[c]js

// seed command: sequelize seed:create --name PermissionData
// import dotenv from 'dotenv';
// dotenv.config();

import 'dotenv/config.js';

const username = process.env.NAME;
const password = process.env.PASSWORD;
const database = process.env.DATABASE;
const host = process.env.HOST;
const port = process.env.DB_PORT;
const dialect = process.env.DIALECT;
const node_env = process.env.NODE_ENV;
const session_secret = process.env.SESSION_SECRET;
const base_url = process.env.BASE_URL;
const client_url = process.env.CLIENT_APP_LOC;
const secure_cookie = process.env.SECURE_COOKIE;

const config = {
    dev: {
        username,
        password,
        database,
        host,
        port,
        dialect,
        logging: true,
        session_secret,
        base_url,
        client_url,
        secure_cookie,
    },
    testing: {
        username,
        password,
        database,
        host,
        port,
        dialect,
        logging: true,
        session_secret,
        base_url,
        client_url,
        secure_cookie,
    },
    production: {
        username,
        password,
        database,
        host,
        port,
        dialect,
        logging: true,
        session_secret,
        base_url,
        client_url,
        secure_cookie,
    },
};

export default config[node_env];

Answer 1

I ran into the same issue recently while trying to run migrations. I solved it using help from the docs.

Note: I'm using Node v15.0.0

If you're using babel, install babel-register package

npm i --save-dev babel-register

Edit your .sequelizerc file to include the package import

require("babel-register");

const path = require('path');

module.exports = {
  'config': path.resolve('config', 'config.json'),
  'models-path': path.resolve('models'),
  'seeders-path': path.resolve('seeders'),
  'migrations-path': path.resolve('migrations')
}

In both your .sequelizerc and config.js remove traces of es6, instead use common js (require) for imports and exports.