AWS Serverless: Environment Variables & Secrets

1. Introduction

In serverless applications, environment variables and secrets play a critical role in managing configuration and sensitive data. This lesson will guide you through the concepts, how to manage them in AWS Lambda, and best practices for security.

2. Environment Variables

Environment variables are key-value pairs that can be used to configure your Lambda function. They allow you to pass configuration settings without hardcoding them into your application.

{
  "FunctionName": "my-function",
  "Environment": {
    "KEY_1": "value1",
    "KEY_2": "value2"
  }
}
        

Accessing Environment Variables in Code

You can access these variables in your Lambda function code using the following syntax:

const value1 = process.env.KEY_1;

3. AWS Secrets Manager

AWS Secrets Manager helps you protect access to your applications, services, and IT resources without the upfront investment and on-going maintenance costs of operating your own infrastructure.

Storing Secrets

You can store sensitive information such as database passwords, API keys, and other credentials in AWS Secrets Manager. Here's how to create a secret:

aws secretsmanager create-secret --name MySecret --secret-string '{"username":"admin","password":"mypassword"}'
    

Retrieving Secrets in Lambda

You can retrieve secrets in your Lambda function using the AWS SDK:

const AWS = require('aws-sdk');
const secretsManager = new AWS.SecretsManager();

async function getSecretValue(secretName) {
    const data = await secretsManager.getSecretValue({ SecretId: secretName }).promise();
    return JSON.parse(data.SecretString);
}
    

4. Best Practices

• Use environment variables to store non-sensitive configuration values.
• Store sensitive information such as passwords and API keys in AWS Secrets Manager.
• Limit the permissions of your Lambda functions to only what is necessary.
• Regularly rotate secrets and keys to enhance security.
• Use encryption for sensitive data at rest and in transit.

5. FAQ