Node JS sequelize Do Not Close Automatically when the Script Done

Question

I am facing some problem with my DB connection design with sequelize.js. What I want to achieve is to have a centralize connection and configuration files for my application DB connection. Therefore I have created a file name database.js as below.

const Sequelize = require("sequelize");
const dbConfig = require("../../config/database.json");

const db = {};

sequelize = new Sequelize({
  dialect: dbConfig.dialect,
  database: dbConfig.database,
  username: dbConfig.username,
  password: dbConfig.password,
  host: dbConfig.host,
  port: dbConfig.port,
  operatorsAliases: false,
  logging: false,

  pool: {
    max: 5,
    min: 0,
    acquire: 30000,
    idle: 10000
  }
});

db.Sequelize = Sequelize;
db.sequelize = sequelize;

module.exports = db;

If there is any scripts going to use database, I just have to require the database.js file. However, there is a problem when my script is finished, the process is not exiting (terminal hang there) because of the sequelize connection is not close.

I have tried to call the close function on the finally block but this causing others query script not working (if I call it on every query block) due to the fact that they are sharing same instant. Once the first query done, then the connection will be closed.

sequelize
  .query("SELECT * FROM users WHERE id = ?", {
    replacements: [userId],
    type: sequelize.QueryTypes.SELECT,
    model: User,
    mapToModel: true
  })
  .then(users => {    
    console.log(users);
  })
  .finally(() => {
    sequelize.close();
  });

I can close the connection on the last query, but it is stupid that whenever I got a new query that will need to execute at last, I will have to move the close to the new query block.

I am looking for a clean code that can help to maintain DB connection and also able to automatic close the connection when all scripts are executed.

Answer 1

sequelize.close() returns a promise so use async function and call await sequelize.close()