# variables.tf — Input variables for the Terraform demo. variable "greeting_message" { description = "Message to write to the output file" type = string default = "Hello from Terraform!" } variable "environment" { description = "Deployment environment name" type = string default = "dev" validation { condition = contains(["dev", "staging", "prod"], var.environment) error_message = "Environment must be dev, staging, or prod." } }