Writing conditional expressions

When writing the Terraform configuration, we may need to make the code more dynamic by integrating various conditions. In this recipe, we will discuss an example of an equal condition operation.

Getting ready

For this recipe, we will use the Terraform configuration we wrote in the previous recipe, whose code is available at https://github.com/PacktPublishing/Terraform-Cookbook/tree/master/CHAP02/fct.

We will complete this code by adding a condition to the name of the Resource Group. This condition is as follows: if the name of the environment is equal to Production, then the name of the Resource Group will be in the form RG-<APP NAME>; otherwise, the name of the Resource Group will be in the form RG-<APP NAME>-<ENVIRONMENT NAME>.

How to do it…

In the Terraform configuration of the main.tf file, modify the code of the Resource Group, as follows:

resource "azurerm_resource_group" "rg-app" {
    name = var.environment == "Production" ? upper(format("RG-%s",var.app-name)) : upper(format("RG-%s-%s",var.app-name,var.environment))
    location = "westeurope"
}

How it works…

Here, we added the following condition:

condition ? true assert : false assert

The result of executing Terraform commands on this code if the environment variable is equal to production can be seen in the following screenshot:

If the environment variable is not equal to production, we'll get the following output:

See also

Documentation on the various conditions of Terraform can be found at https://www.terraform.io/docs/configuration/expressions.html#conditional-expressions.