A downstream workspace in HCP Terraform needs to automatically trigger a plan after a successful apply in an upstream workspace. How do you configure this?
Run Triggers let a downstream workspace watch specified upstream workspaces and queue a plan automatically once their apply succeeds. This directly satisfies the stem's requirement for automatic triggering, since no manual run or webhook scripting is needed.
Why this answer
Run Triggers in HCP Terraform allow a downstream workspace to automatically queue a run when a specified upstream workspace completes a successful apply. This is the native mechanism for chaining workspaces, ensuring that dependent infrastructure is updated only after its dependencies are provisioned.
Exam trap
The trap is confusing Auto-apply with Run Triggers; Auto-apply automates the apply step within a single workspace, while Run Triggers automate cross-workspace run initiation.
How to eliminate wrong answers
Option B is wrong because enabling 'Auto-apply' in the upstream workspace only controls whether runs in that workspace are automatically applied after a plan; it does not trigger runs in other workspaces. Option C is wrong because setting a 'TF_VAR' environment variable provides input variables to Terraform configurations but does not trigger runs across workspaces. Option D is wrong because local variables are used within a Terraform module for internal calculations and have no effect on cross-workspace orchestration.