Question

A developer is refactoring a Terraform configuration into a reusable child module for provisioning S3 buckets. Inside the root module, a variable named 'environment' is defined and used. When the developer references var.environment inside the child module's main.tf, Terraform reports an error that the variable is not declared. What is the correct way to make the parent's 'environment' value available to the child module?

Accepted Answer

Declare an input variable inside the child module and pass the value from the parent by setting that argument in the module block.

Answer

Terraform automatically inherits all variables from the root module, so the error indicates a syntax typo that must be fixed.

Answer

Add an output block for 'environment' in the root module so the child can read it during initialization.

Answer

Define a provider alias in the child module that references the parent's variable scope.