Getting Started with Terraform CDK and TypeScript

Part 1: Getting Started with Terraform CDK (Current)
Part 2: Resource Management with CDK
Part 3: Advanced TypeScript Patterns
Part 4: Custom Constructs and Components
Part 5: Testing CDK Applications
Part 6: CI/CD for CDK Projects

Introduction to Terraform CDK

The Cloud Development Kit for Terraform (CDKTF) allows you to use familiar programming languages to define and provision infrastructure. This series focuses on using TypeScript with CDKTF, combining the power of Terraform’s infrastructure management with TypeScript’s type safety and modern development features.

Prerequisites

Before getting started, ensure you have the following installed:

Node.js (version 16 or later)
npm or yarn
Terraform CLI
Git

Setting Up Your Development Environment

First, install the CDK for Terraform CLI:

npm install --global cdktf-cli

Create a new project:

mkdir my-terraform-cdk
cd my-terraform-cdk
cdktf init --template="typescript" --local

This command creates a new TypeScript project with the following structure:

my-terraform-cdk/
├── .gen/
├── .gitignore
├── cdktf.json
├── help
├── jest.config.js
├── main.ts
├── package.json
├── tsconfig.json
└── __tests__/

Understanding the Project Structure

cdktf.json: Configuration file for your CDK for Terraform project
main.ts: Main application file where you define your infrastructure
.gen/: Generated provider bindings
__tests__/: Directory for your tests

Your First CDK Application

Let’s create a simple AWS infrastructure using CDKTF. First, install the AWS provider:

npm install @cdktf/provider-aws

Update your main.ts:

import { Construct } from "constructs";
import { App, TerraformStack } from "cdktf";
import { AwsProvider } from "@cdktf/provider-aws/lib/provider";
import { Instance } from "@cdktf/provider-aws/lib/instance";

class MyStack extends TerraformStack {
  constructor(scope: Construct, id: string) {
    super(scope, id);

    // AWS Provider
    new AwsProvider(this, "AWS", {
      region: "us-west-2",
    });

    // EC2 Instance
    new Instance(this, "HelloWorld", {
      ami: "ami-0735c191cf914754d",
      instanceType: "t2.micro",
      tags: {
        Name: "HelloWorld",
      },
    });
  }
}

const app = new App();
new MyStack(app, "my-stack");
app.synth();

Key Concepts

1. Constructs

Constructs are the basic building blocks of CDK apps. They represent a cloud component and encapsulate everything AWS CDK needs to create the component.

2. Stacks

Stacks are the unit of deployment in CDK. They contain constructs and are deployed as a single unit.

3. Apps

The App construct is the root of your CDK application. It’s responsible for synthesizing the Terraform configuration.

Working with CDKTF

Synthesizing

To generate Terraform configuration:

cdktf synth

This command creates a cdktf.out directory containing the synthesized Terraform configuration.

Deploying

To deploy your infrastructure:

cdktf deploy

Destroying

To destroy the infrastructure:

cdktf destroy

TypeScript Benefits

Using TypeScript with CDKTF provides several advantages:

Type Safety: Catch errors before deployment
IDE Support: Get autocompletion and inline documentation
Object-Oriented Programming: Use classes and inheritance
Modern Development Features: Utilize async/await, modules, and more

Best Practices

Version Control: Always use version control for your CDK projects
Type Safety: Leverage TypeScript’s type system
Code Organization: Keep stacks focused and modular
Documentation: Document your constructs and configurations
Testing: Write unit tests for your constructs

Next Steps

In Part 2: Resource Management with CDK, we’ll explore how to manage different types of resources, handle dependencies, and work with state in CDKTF.

Series Navigation