Convert Terraform Variable Definitions to JSON

Terraform Variables in HCL and JSON

Variables are the input parameters of a Terraform module. Each variable block defines a single input with optional type, default value, description, and validation rules.

HCL Variable Definitions

variable "region" {
  description = "AWS region for resource deployment"
  type        = "string"
  default     = "us-east-1"
}

variable "instance_count" {
  description = "Number of instances to launch"
  type        = "number"
  default     = 2
}

variable "enable_logging" {
  description = "Enable CloudWatch logging"
  type        = "bool"
  default     = true
}

variable "allowed_cidrs" {
  description = "CIDR blocks allowed to access the service"
  type        = "list(string)"
  default     = ["10.0.0.0/8", "172.16.0.0/12"]
}

JSON Structure

Each variable name becomes a key under the variable object:

{
  "variable": {
    "region": {
      "description": "AWS region for resource deployment",
      "type": "string",
      "default": "us-east-1"
    },
    "instance_count": {
      "description": "Number of instances to launch",
      "type": "number",
      "default": 2
    }
  }
}

Type Expressions

In HCL, type constraints like string, number, bool, list(string), and map(string) are expressions. In JSON, they are represented as strings. Complex types like object({name = string, age = number}) also become string representations.

Validation Rules

Variable validation blocks with condition and error_message attributes translate to nested objects. The condition expression becomes a string in JSON.