Terraform Variable Generator

This tool generates two files: variables.tf (the variable declarations with type, description, default, sensitive flag, and optional validation blocks) and terraform.tfvars (the variable value assignments). These are the standard Terraform files for defining and setting input variables.

All primitive types: string, number, bool. Collection types: list(string), list(number), map(string), set(string). And 'any' for untyped variables. For complex nested types like object({}) or tuple([]), you can type them manually in the HCL default value field.

variables.tf declares the variables — their name, type, description, default, and validation rules. It's part of your module's interface and should be committed to source control. terraform.tfvars provides actual values for those variables. For sensitive or environment-specific values, use a .tfvars file that is gitignored, or pass values via environment variables (TF_VAR_name) or -var flags.

Marking a variable as sensitive tells Terraform to redact its value in plan output, apply output, and state file display. The value is still stored in state, but Terraform won't print it in logs. This is recommended for passwords, API keys, and private keys. You should still encrypt your state backend (S3 + KMS, Terraform Cloud) for full protection.

Validation blocks (introduced in Terraform 0.13) let you add custom constraints to variables. The 'condition' is a Terraform expression that must evaluate to true for the value to be accepted — you can use var.<name> to reference the variable being validated. The 'error_message' is shown when validation fails. Example: condition = var.instance_count >= 1 && var.instance_count <= 100.

String defaults must be quoted: "us-east-1". Number defaults are plain: 42. Boolean defaults: true or false. List defaults: ["a", "b", "c"]. Map defaults: { key = "value" }. Set defaults use the same syntax as list. Leave the default field empty for required variables (no default means Terraform will prompt for the value or error if not provided).