Module structure and conventions in Terraform - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Terraform Module Inputs

Which of the following correctly describes how to define an input variable in a Terraform module?

A parameter "region" { default = "us-west-1" }

B input "region" { type = string default = "us-west-1" }

C var region = "us-west-1"

D variable "region" { type = string default = "us-west-1" }

💡 Hint

Terraform uses a specific block keyword to declare variables.

Terraform input variables are declared using the variable block with a name and optional attributes like type and default.

❓ Configuration

intermediate

Correct Output Declaration in Terraform Module

Which option correctly defines an output named instance_ip in a Terraform module?

A output instance_ip = aws_instance.web.private_ip

B output "instance_ip" { value = aws_instance.web.private_ip }

C output "instance_ip" = aws_instance.web.private_ip

D output { name = "instance_ip" value = aws_instance.web.private_ip }

💡 Hint

Outputs use a block with a name and a value attribute.

Terraform outputs are declared with an output block naming the output and specifying the value to expose.

❓ Architecture

advanced

Best Practice for Module Directory Structure

Which directory structure follows Terraform best practices for a reusable module named network?

A

network/
  main.tf
  variables.tf
  outputs.tf
  README.md

B

network/
  network.tf
  inputs.tf
  results.tf
  docs.md

C

network/
  main.tf
  vars.tf
  outs.tf
  README.md

D

network/
  terraform.tf
  variables.tf
  outputs.tf
  README.md

💡 Hint

Look for standard file names used in Terraform modules.

Terraform modules typically use main.tf for resources, variables.tf for inputs, outputs.tf for outputs, and README.md for documentation.

❓ security

advanced

Handling Sensitive Variables in Terraform Modules

Which option correctly marks a variable as sensitive in a Terraform module to avoid showing its value in logs?

A variable "db_password" { type = string private = true }

B variable "db_password" { type = string hidden = true }

C variable "db_password" { type = string sensitive = true }

D variable "db_password" { type = string secret = true }

💡 Hint

Terraform uses a specific attribute to mark variables as sensitive.

The sensitive = true attribute in a variable block tells Terraform to hide the value in output and logs.

❓ service_behavior

expert

Effect of Module Source Changes on Terraform State

You update the source attribute of a Terraform module to point to a new version. What happens to the existing resources managed by the old module version when you run terraform apply?

A Terraform treats the new module as a separate resource set and plans to create new resources while keeping old ones unless explicitly destroyed.

B Terraform ignores the source change and continues using the old module version until manually refreshed.

C Terraform deletes all old resources immediately before applying the new module changes.

D Terraform automatically updates existing resources in place to match the new module source without recreating them.

💡 Hint

Think about how Terraform tracks resources and modules in state files.

Changing the module source is treated as a new module instance. Terraform plans to create new resources from the new source and keeps old resources unless you remove or replace them explicitly.