How can I source Terraform HCL variables in bash? - bash

Question

I have Terraform variables defined like
variable "location" {
type = string
default = "eastus"
description = "Desired Azure Region"
}
variable "resource_group" {
type = string
default = "my-rg"
description = "Desired Azure Resource Group Name"
}
and potentially / partially overwritten in terraform.tfvars file
location = "westeurope"
and then defined variables as outputs e.g. a file outputs.tf:
output "resource_group" {
value = var.resource_group
}
output "location" {
value = var.location
}
How can I "source" the effective variable values in a bash script to work with these values?

Answer 1

One way is to use Terraform output values as JSON and then an utility like jq to convert and source as variables:
source <(terraform output --json | jq -r 'keys[] as $k | "\($k|ascii_upcase)=\(.[$k] | .value)"')
note that output is only available after executing terraform plan, terraform apply or even a terraform refresh
If jq is not available or not desired, sed can be used to convert Terraform HCL output into variables, even with upper case variable names:
source <(terraform output | sed -r 's/^([a-z_]+)\s+=\s+(.*)$/\U\1=\L\2/')
or using -chdir argument if Terraform templates / modules are in another folder:
source <(terraform -chdir=$TARGET_INFRA_FOLDER output | sed -r 's/^([a-z_]+)\s+=\s+(.*)$/\U\1=\L\2/')
Then these variables are available in bash script:
LOCATION="westeurope"
RESOURCE_GROUP="my-rg"
and can be addressed as $LOCATION and $RESOURCE_GROUP.