Removing region from Resource Group name - terraform

Question

How would I go about removing the location code (aus) from the Resource Group creation.
from:
rg-d-lxr-aus-app1
to
rg-d-lxr-app1
I only want this to affect the only RG and not any other resources eg vnets/keyvaults etc
app1
locals.tf
locals {
full_env_code = format("%s-%s-%s", lower(var.environment_code), lower(var.deployment_code), lower(var.location_code))
}
resource_groups.tf
module "rg-app1" {
source = "git::ssh://git#ssh.dev.azure.com/*"
resource_group_name = format("rg-%s-%s", local.full_env_code, lower(var.name_suffix))
location = var.location
}
variables.tf
variable "location" {
description = "Location in which to deploy resources"
# default = "Australia Southeast"
}
variable "environment_code" {
description = "Environment code"
# default = "d"
}
variable "environment" {
description = "Environment"
# default = "d"
}
variable "deployment_code" {
description = "Deployment code"
# default = "d"
}
variable "location_code" {
description = "Location code"
# default = "d"
}
dev.tfvars
environment = "non-prod"
environment_code = "d"
deployment_code = "my org"
location_code = "aus"
location = "Australia Southeast"
name_suffix = "app1"
Output of TF Plan
Terraform will perform the following actions:
# module.rg-sharegate.azurerm_resource_group.rg will be created
+ resource "azurerm_resource_group" "rg" {
+ id = (known after apply)
+ location = "australiasoutheast"
+ name = "rg-d-lxr-aus-app1"
}
Plan: 1 to add, 0 to change, 0 to destroy.
I am thinking we need to modify the RG module and use the split command, but i'm not sure how to go about it
module "rg-app1" {
resource_group_name = format("rg-%s-%s", local.full_env_code, lower(var.name_suffix))

Answer 1

You can use a mixture of built-in Terraform functions to achieve what you're after.
Local Code to recreate a MRE for you:
locals {
rg_string = "rg-d-lxr-aus-app1"
// Use split by "-" to create an array so we can use contains()
is_rg = contains(split("-", local.rg_string), "rg")
final_rg_string = local.is_rg ? replace(local.rg_string, "aus-", "") : local.rg_string
not_rg_string = "blah-d-lxr-aus-app1"
is_not_rg = contains(split("-", local.not_rg_string), "rg")
final_not_rg_string = local.is_not_rg ? replace(local.not_rg_string, "aus-", "") : local.not_rg_string
}
Result using Terraform Console:
> local.is_rg
true
> local.final_rg_string
"rg-d-lxr-app1"
> local.is_not_rg
false
> local.final_not_rg_string
"blah-d-lxr-aus-app1"
Links:
https://www.terraform.io/language/functions/replace
https://www.terraform.io/language/functions/contains
https://www.terraform.io/language/functions/split
You'll likely not need to duplicate the logic but I did just for demonstrative purposes. For example you can just use your resource_group_name and create your true/false conditions. If you need more help with that please let me know.