Data source block syntax in Terraform - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a data source block for AWS AMI.

Terraform

[1] "aws_ami" "example" {
  most_recent = true
  owners      = ["amazon"]
}

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

Adata

Bresource

Csource

Dprovider

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'resource' instead of 'data' to declare a data source block.

Using 'source' or 'provider' which are incorrect keywords here.

The keyword data is used to declare a data source block in Terraform.

2fill in blank

medium

Complete the code to specify the data source name for AWS VPC.

Terraform

data "aws_vpc" [1] {
  default = true
}

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

Amain

Bdefault

Cvpc_id

Ddefault_vpc

Attempts:

3 left

💡 Hint

Common Mistakes

Using attribute names like 'vpc_id' as the data source name.

Using names that are not valid identifiers or confusing keywords.

The data source name is an identifier you choose. default is commonly used here to indicate the default VPC.

3fill in blank

hard

Fix the error in the data source block by completing the missing attribute.

Terraform

data "aws_subnet" default_subnet {
  [1] = "subnet-12345678"
}

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

Asubnet

Bid

Csubnet_id

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'id' instead of 'subnet_id' which causes Terraform to error.

Using 'name' or 'subnet' which are not valid attributes here.

The correct attribute to specify a subnet by its ID in the data source block is subnet_id.

4fill in blank

hard

Fill both blanks to complete the data source block that fetches the latest Amazon Linux AMI.

Terraform

data "aws_ami" [1] {
  most_recent = true
  filter {
    name   = "name"
    values = ["[2]"]
  }
  owners = ["amazon"]
}

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

Aamazon_linux

Bamzn2-ami-hvm-2.0.*-x86_64-gp2

Clatest_ami

Damzn-ami-hvm-2018.03.0.20181129-x86_64-gp2

Attempts:

3 left

💡 Hint

Common Mistakes

Using an incorrect or outdated AMI name pattern in the filter.

Using a generic or unrelated name for the data source identifier.

The data source name is a label like amazon_linux. The filter value should match the AMI name pattern, here amzn2-ami-hvm-2.0.*-x86_64-gp2 to get the latest Amazon Linux 2 AMI.

5fill in blank

hard

Fill all three blanks to complete the data source block that fetches a subnet by its tag.

Terraform

data "aws_subnet" [1] {
  filter {
    name   = "tag:[2]"
    values = ["[3]"]
  }
}

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

Aselected_subnet

BEnvironment

Cproduction

DName

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect tag keys or values that do not exist.

Using generic names that do not clearly identify the data source.

The data source name is selected_subnet. The filter uses the tag key Environment and looks for the value production to find the subnet.

Practice

1. What is the main purpose of a data source block in Terraform?

easy

A. To create new cloud resources from scratch

B. To define variables for Terraform configuration

C. To delete existing cloud resources

D. To read information about existing cloud resources without creating new ones

Solution

1. Step 1: Understand the role of data sources

   Data sources in Terraform are used to fetch information about existing resources, not to create or delete them.

2. Step 2: Compare options with this role

   Only To read information about existing cloud resources without creating new ones describes reading existing resource info without creation, matching the data source purpose.

3. Final Answer:

   To read information about existing cloud resources without creating new ones -> Option D

4. Quick Check:

   Data source = read existing info [OK]

Hint: Data sources read existing resources, not create or delete [OK]

Common Mistakes:

• Confusing data sources with resource blocks
• Thinking data sources create resources
• Assuming data sources delete resources

2. Which of the following is the correct syntax to define a data source block for an AWS AMI in Terraform?

easy

A. data "aws_ami" example { filter { name = "name" values = ["my-ami"] } }

B. resource "aws_ami" "example" { filter { name = "name" values = ["my-ami"] } }

C. data "aws_ami" "example" { filter { name = "name" values = ["my-ami"] } }

D. data aws_ami example { filter { name = "name" values = ["my-ami"] } }

Solution

1. Step 1: Identify correct block type and syntax

   Data source blocks start with data, followed by resource type and local name in quotes.

2. Step 2: Check each option

   data "aws_ami" "example" { filter { name = "name" values = ["my-ami"] } } uses correct quotes and block structure. resource "aws_ami" "example" { filter { name = "name" values = ["my-ami"] } } uses resource instead of data. Options A and C miss quotes around local name or resource type.

3. Final Answer:

   data "aws_ami" "example" { filter { name = "name" values = ["my-ami"] } } -> Option C

4. Quick Check:

   Data source syntax = data "type" "name" { ... } [OK]

Hint: Data source block uses data "type" "name" with quotes [OK]

Common Mistakes:

• Using resource instead of data
• Omitting quotes around type or name
• Incorrect block nesting or missing braces

3. Given this Terraform data source block:

data "aws_vpc" "selected" {
  filter {
    name   = "tag:Name"
    values = ["main-vpc"]
  }
}

What will data.aws_vpc.selected.id return?

medium

A. The ID of the VPC tagged with Name=main-vpc

B. The name tag value main-vpc

C. A list of all VPC IDs in the AWS account

D. An error because filter syntax is invalid

Solution

1. Step 1: Understand the filter block

   The filter selects the VPC resource with tag Name equal to main-vpc.

2. Step 2: Identify the returned attribute

   data.aws_vpc.selected.id accesses the ID of the matched VPC, not the tag value or a list.

3. Final Answer:

   The ID of the VPC tagged with Name=main-vpc -> Option A

4. Quick Check:

   Filter selects resource, .id returns its ID [OK]

Hint: Filter narrows resource, .id returns its unique ID [OK]

Common Mistakes:

• Confusing tag value with resource ID
• Expecting a list instead of single ID
• Assuming filter syntax is wrong

4. Identify the error in this Terraform data source block:

data "aws_subnet" "example" {
  filter {
    name = "availability-zone"
    values = "us-west-2a"
  }
}

medium

A. The values attribute should be a list, not a string

B. The filter block is missing a closing brace

C. The data source type aws_subnet does not support filters

D. The local name example must be uppercase

Solution

1. Step 1: Check the values attribute type

   In Terraform, filter values must be a list, even if only one value is given.

2. Step 2: Verify the given values

   The code uses a string instead of a list, which causes a syntax error.

3. Final Answer:

   The values attribute should be a list, not a string -> Option A

4. Quick Check:

   Filter values = list, not string [OK]

Hint: Always use list syntax ["value"] for filter values [OK]

Common Mistakes:

• Using string instead of list for values
• Assuming filter block needs no braces
• Thinking local name case matters

5. You want to use a data source block to get the latest Amazon Linux 2 AMI ID filtered by owner and name pattern. Which of these blocks correctly achieves this?

hard

A. resource "aws_ami" "latest" {
most_recent = true
owners = ["amazon"]
filter {
name = "name"
values = ["amzn2-ami-hvm-*-x86_64-gp2"]
}
}

B. data "aws_ami" "latest" {
most_recent = true
owners = ["amazon"]
filter {
name = "name"
values = ["amzn2-ami-hvm-*-x86_64-gp2"]
}
}

C. data "aws_ami" "latest" {
filter {
name = "owner"
values = ["amazon"]
}
filter {
name = "name"
values = ["amzn2-ami-hvm-*-x86_64-gp2"]
}
}

D. data "aws_ami" "latest" {
most_recent = true
owner = "amazon"
filter {
name = "name"
values = ["amzn2-ami-hvm-*-x86_64-gp2"]
}
}

Solution

1. Step 1: Confirm correct block type and attributes

   Use data block for reading AMI info, with most_recent = true and owners as a list.

2. Step 2: Check filter and owner syntax

   data "aws_ami" "latest" { most_recent = true owners = ["amazon"] filter { name = "name" values = ["amzn2-ami-hvm-*-x86_64-gp2"] } } correctly uses owners list and a filter for name pattern. data "aws_ami" "latest" { filter { name = "owner" values = ["amazon"] } filter { name = "name" values = ["amzn2-ami-hvm-*-x86_64-gp2"] } } incorrectly filters owner as a filter. resource "aws_ami" "latest" { most_recent = true owners = ["amazon"] filter { name = "name" values = ["amzn2-ami-hvm-*-x86_64-gp2"] } } uses resource block instead of data. data "aws_ami" "latest" { most_recent = true owner = "amazon" filter { name = "name" values = ["amzn2-ami-hvm-*-x86_64-gp2"] } } uses singular owner instead of owners list.

3. Final Answer:

   data "aws_ami" "latest" { most_recent = true owners = ["amazon"] filter { name = "name" values = ["amzn2-ami-hvm-*-x86_64-gp2"] } } -> Option B

4. Quick Check:

   Use data block, owners list, most_recent true [OK]

Hint: Use owners list and most_recent true in data block [OK]

Common Mistakes:

• Using resource block instead of data
• Filtering owner instead of using owners attribute
• Using singular owner instead of owners list