hashicorp/setup-terraform

Install the Terraform CLI and (optionally) wrap it to expose plan output in later steps.

Official actionCategory: Infrastructure & KubernetesLatest v3View on GitHub

What it does

hashicorp/setup-terraform installs the Terraform CLI. By default it installs a wrapper script so the outputs of terraform steps (stdout, stderr, exitcode) are available to later steps.

That wrapper is what lets you post a formatted plan as a PR comment.

Usage

workflow (.yml)

steps:
  - uses: actions/checkout@v4
  - uses: hashicorp/setup-terraform@v3
    with:
      terraform_version: 1.9.0
  - run: terraform init
  - id: plan
    run: terraform plan -no-color
  # steps.plan.outputs.stdout is available thanks to the wrapper

Inputs

Input	Description	Default	Required
`terraform_version`	Version to install, e.g. 1.9.0 or latest.	`latest`	No
`terraform_wrapper`	Install the output-capturing wrapper.	`true`	No
`cli_config_credentials_token`	Terraform Cloud/Enterprise API token.	-	No

Notes

Set terraform_wrapper: false if another tool needs the raw terraform binary without the wrapper.

Common errors

steps.plan.outputs.stdout being empty usually means terraform_wrapper was disabled.
A version like latest can change plan output between runs; pin terraform_version for reproducible CI.

Security and pinning

Pin terraform_version and the action SHA. Pass any Terraform Cloud token from a secret.

Alternatives and related

aws-actions/configure-aws-credentialsAuthenticate to AWS in a workflow, ideally by assuming a role with OIDC (no stored keys). azure/loginLog in to Azure in a workflow, using OIDC federated credentials or a service principal.

Frequently asked questions

How do I comment a Terraform plan on a PR?

Keep the wrapper on (default), capture steps.<id>.outputs.stdout from the plan step, and post it with actions/github-script.