Output

expected time	requirements
30 minutes	A computer with Terraform installed.

Goal: Understand how output can displayed.

Explanation

The command terraform show will display everything that Terraform knows. It basically dumps the state. All that output may be a little too much, so you may want to output specific values. Think of:

• An IP address of the load balancer.
• An instruction what to do next.
• The DNS name of the websites that Terraform deployed.

Howto

You can specify Terraform to show output. Mostly these outputs are stored in outputs.tf, sometimes the output is specified in a function-specific file, such as networking.tf or instances.tf.

output "ip_addr" {
  value       = google_comput_instance.default.network_interface.0.access_config.0.nat_ip
  description = "The public NAT ip address of the instance."
}

If a Terraform module specifies output, that output may be used elsewhere:

resource "fake" "default" {
  name    = "www"
  ip_addr = module.THE_NAME_OF_THE_MODULE.ip_addr
}

There is an attribute sensitive. This indicates that Terraform should not show the sensitive information as output, but other modules or resources can use the item.

You may add depends_on list to indicate that Terraform should first create items in the list before showing the information.

You can use functions to transform the output.

Demo

• See this Azure file.
• See this GCP file

Assignment

• In one of your directories/repositories that you already have, add an output attribute.
• Show "Hello world!" as output.
• Use a function to show ["Hello world!"].

Questions:

1. Does adding sensitive = true parameter make data fully safe?