Book Image

Expert AWS Development

By : Atul Mistry
Book Image

Expert AWS Development

By: Atul Mistry

Overview of this book

Expert AWS Development begins with the installation of the AWS SDK and you will go on to get hands-on experience of creating an application using the AWS Management Console and the AWS Command Line Interface (CLI). Then, you will integrate applications with AWS services such as DynamoDB, Amazon Kinesis, AWS Lambda, Amazon SQS, and Amazon SWF. Following this, you will get well versed with CI/CD workflow and work with four major phases in the release process – Source, Build, Test, and Production. Then, you will learn to apply AWS Developer tools to your Continuous Integration (CI) and Continuous Deployment (CD) workflow. Later, you will learn about user authentication using Amazon Cognito, and also how you can evaluate the best architecture as per your infrastructure costs. You will learn about Amazon EC2 service and will deploy an app using it. You will also deploy a practical real-world example of a CI/CD application with the Serverless Application Framework, which is known as AWS Lambda. Finally, you will learn how to build, develop, and deploy the Application using AWS Developer tools such as AWS CodeCommit, AWS CodeBuild, AWS CodeDeploy, and AWS CodePipeline, as per your project requirements.
Table of Contents (16 chapters)
Title Page
Packt Upsell

Lambda and Lambda@Edge advanced topics and best practices

In Chapter 7, Evaluating the Best Architecture, we learnt about AWS Lambda basics. Here, we will discuss advanced topics and best practices about AWS Lambda and AWS Lambda@Edge.

The following sections provide advanced features to build Lambda applications:

  • Environment variables
  • Dead letter queues (DLQ)

Environment variables

Environment variables are key-value pairs. You can create and modify them from function configuration using the AWS Lambda Management Console, AWS Lambda CLI, or AWS Lambda SDK. For key-value pairs, AWS Lambda makes these available from the Lambda function code, which is using standard APIs. These APIs can support any language, such as Node.js functions, which is using process.env.

Lambda functions enable environment variables to pass settings dynamically to the libraries and function code without any code being changed. Libraries can use environment variables to know which directory to install files to, where to store...