Automating AWS with Custom Terraform Scripts

Terraform is an open-source infrastructure as code (IaC) software tool that enables you to safely and predictably create, change, and improve infrastructure. Using Terraform, you can define both cloud and on-prem resources in human-readable configuration files that you can version, reuse, and share.

I'll guide you through creating custom Terraform scripts to automate the provisioning of certain AWS services. We’ll cover:

• Setting up Terraform
• Writing Terraform configurations
• Provisioning an AWS EC2 instance
• Creating an S3 bucket
• Setting up an RDS instance

Prerequisites

Before we begin, make sure you have the following:

1. An AWS account
2. AWS CLI configured with your credentials
3. Terraform installed on your machine

Setting Up Terraform

First, ensure that Terraform is installed. You can download it from the Terraform website.

Initialize a new Terraform project by creating a directory and navigating into it:

mkdir terraform-aws
cd terraform-aws

Create a main.tf file where we will define our infrastructure.

Writing Terraform Configurations

Provisioning an AWS EC2 Instance

To create an EC2 instance, you need to define the AWS provider and the resource type in your main.tf file:

# main.tf

provider "aws" {
  region = "us-east-1"
}

resource "aws_instance" "example" {
  ami           = "ami-0c55b159cbfafe1f0" # Amazon Linux 2 AMI
  instance_type = "t2.micro"

  tags = {
    Name = "ExampleInstance"
  }
}

This script specifies that we want to use the AWS provider and creates an EC2 instance with the specified AMI and instance type.

Creating an S3 Bucket

To create an S3 bucket, add the following resource block to your main.tf file:

resource "aws_s3_bucket" "example" {
  bucket = "my-unique-bucket-name-123"
  acl    = "private"

  tags = {
    Name        = "ExampleBucket"
    Environment = "Dev"
  }
}

This script will create an S3 bucket with a unique name and private access.

### Setting Up an RDS Instance
To set up an RDS instance, include the following configuration:

```main.tf
resource "aws_db_instance" "example" {
  allocated_storage    = 20
  engine               = "mysql"
  engine_version       = "5.7"
  instance_class       = "db.t2.micro"
  name                 = "mydb"
  username             = "admin"
  password             = "password"
  parameter_group_name = "default.mysql5.7"
  skip_final_snapshot  = true

  tags = {
    Name = "ExampleDBInstance"
  }
}

This script provisions a MySQL database instance with the specified parameters.

Applying the Configuration

Once you have defined your infrastructure in the main.tf file, you can apply the configuration using the following commands:

1. Initialize the Terraform configuration:

terraform init

2. Validate the configuration:

terraform validate

Apply the configuration:

terraform apply

You'll be prompted to confirm the action. Type yes to proceed.

Conclusion

In this post, we covered how to create custom Terraform scripts to automate the provisioning of AWS services like EC2 instances, S3 buckets, and RDS instances. Terraform provides a powerful way to manage your infrastructure as code, making it easy to version control and share configurations.

Feel free to expand these scripts to include more complex resources and configurations based on your needs. Happy automating!