mysqlnode.jsexpressconnection-pooling

Does this NodeJS custom ORM approach support database connection pooling?


I have a file which creates the database connection pool called pool.js like this

import mysql from 'mysql2';
import dotenv from 'dotenv';

dotenv.config();

const pool = mysql.createPool({
    host: process.env.DB_HOST,
    user: process.env.DB_USER,
    password: process.env.DB_PASSWORD,
    database: process.env.DB_NAME,
    port: process.env.DB_PORT,
    connectionLimit: 5
}).promise();

export default pool;

A Base model class which handles query execution like this

import pool from './pool.js'

class BaseModel{
    async runSQL(sql){
        const [rows] = await pool.query(sql, this.params)
        return rows
    }
}

And a User model class which calls the base model database method like this

import BaseModel from "../helpers/BaseModel.js"

class User extends BaseModel{
    async create(props){
        const response = await this.runSQL(sql)
        return response
    }
}

export default new User

Does this implementation satisfy the database connection pooling usage?


Solution

  • Yes, you are using connection pooling in the right way.

    If you need more control on connection pool, you can play with a couple of more params like maxIdle or idleTimeout.

    connectionLimit: 10,
    maxIdle: 10, // max idle connections, the default value is the same as connectionLimit
    idleTimeout: 60000, // idle connections timeout, in milliseconds, the default value 60000
    

    You can find more infos here.

    Just remember that (from the linked docs)

    The pool does not create all connections upfront but creates them on demand until the connection limit is reached.