Initialise a sequelize MySQL database with .env variables. Refer to specific variable names in the code when writing out .env file.

envBasedSequelizeInit.js

'use strict';
const fs = require('fs');
const path = require('path');
const Sequelize = require('sequelize');
const process = require('process');
const basename = path.basename(__filename);
const db = {};
require('dotenv').config();
// Create sequelize instance using config
let sequelize = new Sequelize(
  process.env.DB_NAME, process.env.DB_USER, process.env.DB_PWD,
  {
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
    dialect: 'mysql',
    logging: false,
    timezone: '+08:00'
  }
);
fs
  .readdirSync(__dirname)
  .filter(file => {
    return (file.indexOf('.') !== 0) && (file !== basename) &&
      (file.slice(-3) === '.js');
  })
  .forEach(file => {
    const model = require(path.join(__dirname, file))(sequelize,
      Sequelize.DataTypes);
    db[model.name] = model;
  });
Object.keys(db).forEach(modelName => {
  if (db[modelName].associate) {
    db[modelName].associate(db);
  }
});
db.sequelize = sequelize;
db.Sequelize = Sequelize;
module.exports = db;