Check blocks for assertions in Terraform - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a check block that asserts the instance type is t2.micro.

Terraform

resource "aws_instance" "example" {
  instance_type = "t2.micro"

  [1] {
    condition     = var.instance_type == "t2.micro"
    error_message = "Instance type must be t2.micro"
  }
}

Drag options to blanks, or click blank then click option'

Aassert

Bcheck_block

Ccheck

Dverify

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'assert' or 'verify' instead of 'check' causes syntax errors.

Forgetting to include the check block inside the resource.

The correct keyword to define a check block in Terraform is check. This block allows you to assert conditions on resource attributes.

2fill in blank

medium

Complete the code to assert that the AMI ID is not empty in the check block.

Terraform

resource "aws_instance" "example" {
  ami           = var.ami_id
  instance_type = "t2.micro"

  check {
    condition     = [1]
    error_message = "AMI ID must not be empty"
  }
}

Drag options to blanks, or click blank then click option'

Avar.ami_id != ""

Bvar.ami_id > ""

Cvar.ami_id = ""

Dvar.ami_id == ""

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment operator '=' instead of comparison.

Checking for equality to empty string instead of inequality.

The condition should check that var.ami_id is not an empty string using != "".

3fill in blank

hard

Fix the error in the check block condition to correctly assert that the count is greater than zero.

Terraform

resource "aws_instance" "example" {
  count         = var.instance_count
  instance_type = "t2.micro"

  check {
    condition     = var.instance_count [1] 0
    error_message = "Instance count must be greater than zero"
  }
}

Drag options to blanks, or click blank then click option'

A>

B==

C<=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<=' or '<' which allow zero or negative values.

Using '==' which only allows exactly zero.

The condition should assert that var.instance_count is greater than zero using the '>' operator.

4fill in blank

hard

Fill both blanks to assert that the environment variable is either 'dev' or 'prod'.

Terraform

variable "environment" {
  type = string
}

resource "aws_instance" "example" {
  instance_type = "t2.micro"

  check {
    condition     = var.environment [1] ["dev", "prod"]
    error_message = "Environment must be 'dev' or 'prod'"
  }
}

Drag options to blanks, or click blank then click option'

A!=

B==

Cnot in

Din

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' which compares to the whole list, causing errors.

Using 'not in' which negates the condition.

The correct operator to check if a value is inside a list is in. The blank uses 'in' to form the condition.

5fill in blank

hard

Fill all three blanks to assert that the tag 'Name' exists and is not empty.

Terraform

resource "aws_instance" "example" {
  tags = {
    Name = var.instance_name
  }

  check {
    condition     = contains(keys(var.tags), [1]) && var.tags[[2]] [3] ""
    error_message = "Tag 'Name' must exist and not be empty"
  }
}

Drag options to blanks, or click blank then click option'

A"Name"

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' to check for non-empty value.

Forgetting to quote the key name 'Name'.

The condition checks if the key 'Name' exists in the tags and that its value is not empty. So, the key name is 'Name' and the operator is '!='.