Hands-on Infrastructure as Code: AWS Deployment with Terraform

I've been building a DevOps automation project on my GitHub page to showcase how Terraform, Ansible and Docker can be used together to quickly deploy, and automate the configuration of assets using Infrastructure as Code (IaC).

Set up local environment variables

For this project, I'm building on AWS. In order to use Terraform, I need to set up environment variables to store my AWS Access Key IDand then my AWS Secret Access Key. It's super important not to share these, or store them in a script that later gets pushed to GitHub.

$ export AWS_ACCESS_KEY_ID=<your_aws_key>
$ export AWS_SECRET_ACCESS_KEY=<your_secret_key>

Main configuration file

Once the local variables are set, two files will be required to create an EC2 instance on AWS through IaC. First, the main.tf file.

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 4.16"
    }
  }

  required_version = ">= 1.2.0"
}

provider "aws" {
  region = var.aws_region
}

resource "aws_instance" "app_server" {
  ami           = var.ami_id
  instance_type = var.instance_type

  tags = {
    Name = "DevOpsDemoInstance"
  }
}

Next, it's time to define a variables.tf file that will store the variables used by main.tf during execution. For simple deployments, like this one, it would be enough to declare the variables in the main.tf file. However, for more complex projects, or when better organisation is needed, or the configuration will be reused, it's best practice to use a variables.tf file. For that reason, that's the approach used here since this is a learning exercise.

Variables file

variable "aws_region" {
  description = "AWS region"
  type        = string
  default     = "ap-southeast-2"
}

variable "instance_type" {
  description = "EC2 instance type"
  type        = string
  default     = "t2.micro"
}

variable "ami_id" {
  description = "The AMI ID for the EC2 instance"
  type        = string
  default     = "ami-0b0a3a2350a9877be"
}

Finally, the next thing is to initialise the directory using terraform init, and then create the infrastructure using terraform applyand reviewing what will be built. Once satisfied, select yes and your AWS infrastructure will be provisioned. Once the proof-of-concept is finished, remember to use terraform destroy to tear down your infrastructure.