Book Image

Mastering AWS CloudFormation - Second Edition

By : Karen Tovmasyan
Book Image

Mastering AWS CloudFormation - Second Edition

By: Karen Tovmasyan

Overview of this book

The advent of DevOps and the cloud revolution has compelled software engineers and operations teams to rethink how to manage complex infrastructures and build resilient solutions. With this AWS book, you’ll find out how you can use Infrastructure as Code (IaC) to simplify infrastructure operations and manage the modern cloud with AWS CloudFormation. This guide covers AWS CloudFormation comprehensively, from template structures to developing complex and reusable infrastructure stacks. It takes you through template validation, stack deployment, and handling deployment failures. It also demonstrates the use of AWS CodeBuild and CodePipeline for automating resource delivery and implementing continuous integration and continuous delivery (CI/CD) practices. As you advance, you’ll learn how to modularize and unify your template on the fly using macros or by fixating the version using modules. You’ll create resources outside of AWS with custom resources and catalog them with the CloudFormation registry. Finally, you’ll improve the way you manage the modern cloud environment on AWS by extending CloudFormation through the AWS serverless application model (SAM) and the AWS cloud development kit (CDK). By the end of this book, you’ll have mastered key AWS CloudFormation concepts and will be able to extend its capabilities for developing and deploying your own infrastructure.
Table of Contents (19 chapters)
Free Chapter
1
Part 1: CloudFormation Internals
4
Part 2: Provisioning and Deployment at Scale
9
Part 3: Extending CloudFormation

Managing CloudFormation IAM permissions

We already know that CloudFormation performs API calls when we create or update the stack. Now, the question is, does CloudFormation have the same powers as a root user?

When you work with production-grade AWS accounts, you need to control access to your environment for humans (yourself and your co-workers) and machines (build systems, other AWS services or resources, and so on). Ignoring the least privilege principle may lead to disastrous security breaches, which is why controlling access for CloudFormation is important.

By default, when the user runs stack creation, they invoke the cloudformation:CreateStack API method. CloudFormation will use that user’s permissions to invoke other API methods during stack creation.

This means that if our user has an IAM policy with an allowed action of ec2:* but attempts to create an RDS instance with CloudFormation, the stack will fail to create, with an error stating that the User is unauthorized...