2.2.1.1. IaC Options & Tools for AWS (CloudFormation, CDK, SAM)
First Principle: Defining infrastructure through machine-readable definition files enables automated, consistent, and repeatable provisioning and management of AWS resources.
Infrastructure as Code (IaC) fundamentally eliminates manual errors and configuration drift.
AWS offers powerful native tools for IaC:
- AWS CloudFormation: (A declarative service for modeling and provisioning AWS resources using JSON/YAML templates.) It manages dependencies and ensures consistent deployments of entire stacks.
- AWS Cloud Development Kit (CDK): (An open-source framework to define cloud resources using familiar programming languages (Python, TypeScript, Java, etc.).) It synthesizes into CloudFormation, offering programmatic control for complex, reusable infrastructure.
- AWS Serverless Application Model (SAM): (A CloudFormation extension simplifying serverless application deployment.) It provides shorthand syntax for Lambda, API Gateway, and DynamoDB, streamlining serverless workflows.
Key IaC Tools:
- CloudFormation: Declarative, YAML/JSON, native AWS.
- CDK: Imperative, programming languages, synthesizes to CloudFormation.
- SAM: CloudFormation extension, serverless-focused, shorthand syntax.
Scenario: A DevOps team needs to provision a new application environment, including EC2 instances, databases, and networking, repeatedly and consistently. They want to manage this infrastructure through code, treating it like application code.
Reflection Question: How does using an IaC tool like AWS CloudFormation or AWS CDK enable automated, version-controlled, and consistent provisioning of entire AWS environments, and what are the benefits over manual provisioning?
These tools allow you to treat your infrastructure like application code, enabling version control, automated testing, and consistent deployments across environments.
š” Tip: Consider how CloudFormation's template-based approach is declarative (you state what you want), while CDK's code-based approach can be more imperative (you define how to build it).