Demo Output Variables

In this hands-on lab, you’ll learn how to configure, apply, and manage output variables in OpenTofu using the random provider. By the end, you’ll be able to expose resource attributes and query them on demand.

1. Setup and Resource Configuration

Change into the sample project directory:
cd /root/OpenTofu-projects/data

Examine the HCL files defining nine resources with the random provider:

# random_integer resources
resource "random_integer" "order1" {
  min = 1
  max = 99999
}

resource "random_integer" "order2" {
  min = 1
  max = 222222
}

# random_uuid resources
resource "random_uuid" "id1" {}
resource "random_uuid" "id2" {}
resource "random_uuid" "id3" {}
resource "random_uuid" "id4" {}
resource "random_uuid" "id5" {}
resource "random_uuid" "id6" {}
resource "random_uuid" "id7" {}

Open the accompanying output.tf to see how each resource is exposed as an output variable.

2. Initialize, Plan, and Apply

Initialize the working directory, preview the plan, and apply the configuration.

Command	Description
`tofu init`	Download providers and initialize the working folder
`tofu plan`	Generate and display the execution plan
`tofu apply`	Apply changes to create resources

tofu init
tofu plan
tofu apply
# Type "yes" to confirm

After a successful apply, you should see:

Apply complete! Resources: 9 added, 0 changed, 0 destroyed.

Outputs:
id1     = "82b3b221-136c-88c6-88c2-e9f878d86a"
id2     = "9687669a-73d4-9717-52a2-6497826815a1"
id3     = "23982b58-763d-49ae-af62-45a7856ac42c"
id4     = "890c9540-59e1-4b28-8fba-9a4f418c0c86"
id5     = "e2171b2e-1ff0-40a6-8fdb-c472f017c5b5"
id6     = "2212bac2-d5c1-ecac-2490-012bcab1f19a"
id7     = "b4e83b80-46c8-4efb-bd73-3a7865d647d6"
order1  = 16106
order2  = 16106

You can learn more about OpenTofu and output variables in the official Terraform Output Variables documentation.

3. Querying Individual Outputs

Test your understanding:

What is the value of id2?
From the example above, id2 = "9687669a-73d4-9717-52a2-6497826815a1".
What is the value of order1?
It is 16106.

You can also fetch specific outputs:

tofu output id2
tofu output order1
# => 16106

4. Inspecting a New Configuration

Switch to the second lab directory and review main.tf:

cd /root/OpenTofu-projects/data/output

In main.tf, you’ll find:

resource "random_pet" "my_pet" {
  length = var.length
}

output "pet-name" {
  value       = random_pet.my_pet.id
  description = "Record the value of pet ID generated by the random pet"
}

If the image below doesn’t render, use the code snippet above to verify your setup.

The image shows a coding environment with a task about inspecting configuration files in a directory. It includes a code editor displaying Terraform code and a terminal window, along with a multiple-choice question about the value of a variable.

Confirm the output:

tofu output pet-name
# => "marlin"

5. Adding a New Output Variable

The same main.tf defines a local_file resource:

resource "local_file" "welcome" {
  filename = "/root/message.txt"
  content  = "Welcome to Kodekloud."
}

Add an output block below it to capture the file’s content:

output "welcome_message" {
  value = local_file.welcome.content
}

Save your changes, then re-run the workflow:

tofu init
tofu plan
tofu apply
# Type "yes" to confirm

Finally, verify the new output:

tofu output welcome_message
# => "Welcome to Kodekloud."

Congratulations! You’ve successfully configured and managed OpenTofu output variables.

Course Introduction

Introduction to Infrastructure as Code

OpenTofu Basics

OpenTofu State

Working with OpenTofu

Remote State

OpenTofu Provisioners

OpenTofu Import, Tainting Resources and Deubugging

OpenTofu Modules

OpenTofu Functions and Conditional Expressions

OpenTofu: Beyond Basics

Course Conclusion

Getting Started with OpenTofu

Demo Output Variables

1. Setup and Resource Configuration

2. Initialize, Plan, and Apply

3. Querying Individual Outputs

4. Inspecting a New Configuration

5. Adding a New Output Variable

Watch Video

Practice Lab

​1. Setup and Resource Configuration

​2. Initialize, Plan, and Apply

​3. Querying Individual Outputs

​4. Inspecting a New Configuration

​5. Adding a New Output Variable

Watch Video

Practice Lab

1. Setup and Resource Configuration

2. Initialize, Plan, and Apply

3. Querying Individual Outputs

4. Inspecting a New Configuration

5. Adding a New Output Variable