Data source block syntax in Terraform - Mini Project: Build & Apply

Data source block syntax

📖 Scenario: You are setting up a Terraform configuration to retrieve information about an existing AWS AMI (Amazon Machine Image) to use in your infrastructure.

🎯 Goal: Build a Terraform configuration that uses a data source block to fetch the latest Amazon Linux 2 AMI ID in the us-east-1 region.

📋 What You'll Learn

Create a data block named aws_ami with the name amazon_linux

Configure the data source to filter for the latest Amazon Linux 2 AMI

Use the owners attribute to specify Amazon's owner ID

Add an output to display the AMI ID

💡 Why This Matters

🌍 Real World

Terraform data sources let you query existing cloud resources to use their information in your infrastructure setup without recreating them.

💼 Career

Understanding data source blocks is essential for cloud engineers and DevOps professionals to integrate existing resources into Terraform-managed infrastructure.

1

Create the data source block skeleton

Create a Terraform data block named aws_ami with the name amazon_linux.

Terraform

# Your code here

Need a hint?

Start with data "aws_ami" "amazon_linux" { } to define the data source block.

2

Add filter and owners attributes

Inside the data "aws_ami" "amazon_linux" block, add a filter block with name = "name" and values = ["amzn2-ami-hvm-*-x86_64-gp2"]. Also add owners = ["137112412989"] to specify Amazon's owner ID.

Terraform

data "aws_ami" "amazon_linux" {
  # Add filter and owners attributes here
}

Need a hint?

Use a filter block with name and values, and add owners outside the filter.

3

Add most_recent attribute

Add the attribute most_recent = true inside the data "aws_ami" "amazon_linux" block to get the latest AMI.

Terraform

data "aws_ami" "amazon_linux" {
  filter {
    name   = "name"
    values = ["amzn2-ami-hvm-*-x86_64-gp2"]
  }
  owners = ["137112412989"]
  # Add most_recent attribute here
}

Need a hint?

Set most_recent = true to ensure the latest AMI is selected.

4

Add output for the AMI ID

Create an output block named ami_id that outputs the value of data.aws_ami.amazon_linux.id.

Terraform

data "aws_ami" "amazon_linux" {
  filter {
    name   = "name"
    values = ["amzn2-ami-hvm-*-x86_64-gp2"]
  }
  owners       = ["137112412989"]
  most_recent  = true
}

# Add output block here

Need a hint?

Use output "ami_id" with value = data.aws_ami.amazon_linux.id to show the AMI ID.