Adding an Amazon RDS DB instance to your Node.js application environment

You can use an Amazon Relational Database Service (Amazon RDS) DB instance to store data gathered and modified by your application. The database can be attached to your environment and managed by Elastic Beanstalk, or created and managed externally.

If you are using Amazon RDS for the first time, add a DB instance to a test environment with the Elastic Beanstalk Management Console and verify that your application is able to connect to it.

To connect to a database, add the driver to your application, load the driver in your code, and create a connection object with the environment properties provided by Elastic Beanstalk. The configuration and connection code vary depending on the database engine and framework that you use.

Note

For learning purposes or test environments, you can use Elastic Beanstalk to add a DB instance.

For production environments, you can create a DB instance outside of your Elastic Beanstalk environment to decouple your environment resources from your database resources. This way, when you terminate your environment, the DB instance isn't deleted. An external DB instance also lets you connect to the same database from multiple environments and perform blue-green deployments. For instructions, see Using Elastic Beanstalk with Amazon RDS.

Adding a DB instance to your environment

To add a DB instance to your environment

1. Open the Elastic Beanstalk console, and in the Regions list, select your AWS Region.

2. In the navigation pane, choose Environments, and then choose the name of your environment from the list.

   Note

   If you have many environments, use the search bar to filter the environment list.

3. In the navigation pane, choose Configuration.

4. In the Database configuration category, choose Edit.

5. Choose a DB engine, and enter a user name and password.

6. Choose Apply.

Adding a DB instance takes about 10 minutes. When the environment update is complete, the DB instance's hostname and other connection information are available to your application through the following environment properties:

Property name	Description	Property value
RDS_HOSTNAME	The hostname of the DB instance.	On the Connectivity & security tab on the Amazon RDS console: Endpoint.
RDS_PORT	The port on which the DB instance accepts connections. The default value varies among DB engines.	On the Connectivity & security tab on the Amazon RDS console: Port.
RDS_DB_NAME	The database name, ebdb.	On the Configuration tab on the Amazon RDS console: DB Name.
RDS_USERNAME	The username that you configured for your database.	On the Configuration tab on the Amazon RDS console: Master username.
RDS_PASSWORD	The password that you configured for your database.	Not available for reference in the Amazon RDS console.

For more information about configuring an internal DB instance, see Adding a database to your Elastic Beanstalk environment.

Downloading a driver

Add the database driver to your project's package.json file under dependencies.

Example package.json – Express with MySQL

{
  "name": "my-app",
  "version": "0.0.1",
  "private": true,
  "dependencies": {
    "ejs": "latest",
    "aws-sdk": "latest",
    "express": "latest",
    "body-parser": "latest",
    "mysql": "latest"
  },
  "scripts": {
    "start": "node app.js"
  }
}

Common driver packages for Node.js

• MySQL – mysql

• PostgreSQL – node-postgres

• SQL Server – node-mssql

• Oracle – node-oracledb

Connecting to a database

Elastic Beanstalk provides connection information for attached DB instances in environment properties. Use process.env.VARIABLE to read the properties and configure a database connection.

Example app.js – MySQL database connection

var mysql = require('mysql');

var connection = mysql.createConnection({
  host     : process.env.RDS_HOSTNAME,
  user     : process.env.RDS_USERNAME,
  password : process.env.RDS_PASSWORD,
  port     : process.env.RDS_PORT
});

connection.connect(function(err) {
  if (err) {
    console.error('Database connection failed: ' + err.stack);
    return;
  }

  console.log('Connected to database.');
});

connection.end();

For more information about constructing a connection string using node-mysql, see npmjs.org/package/mysql.