Terraform/OpenTofu PR Commenter
This action posts the results of Terraform or OpenTofu commands (fmt, init, plan, validate) as pull request comments on GitHub or Gitea. It is designed to work with CI workflows and ensures every command posts a comment, even if it succeeds.
Features
- Supports Terraform and OpenTofu.
- Works on GitHub Actions and Gitea Actions.
- Posts
fmtandplanoutputs with syntax-highlighted diffs. initandvalidateoutputs are posted in expandable<details>blocks.- Automatically updates existing comments or creates new ones.
- Supports per-file diffs for
fmt.
Inputs
| Input | Description | Required | Default |
|---|---|---|---|
command |
Command type (fmt, init, plan, validate) |
Yes | — |
commenter_input |
Stdout or newline-separated file list from the previous step | Yes | — |
commenter_exitcode |
Exit code from the previous step | Yes | — |
pr_number |
Pull request number | No | — |
pr_comments_url |
URL for PR comments API | No | — |
pr_comment_uri |
URI for individual PR comment API | No | — |
github_token |
GitHub token (for GitHub Actions) | No | — |
gitea_token |
Gitea token (for Gitea Actions) | No | — |
gitea_action |
Set to true if running in Gitea Actions |
No | false |
gitea_api_url |
Gitea API URL | No | — |
gitea_repository |
Gitea repository (owner/repo) |
No | — |
highlight_changes |
Enable diff highlighting | No | true |
tf_workspace |
Terraform/OpenTofu workspace | No | default |
Usage
GitHub Actions Example
- name: Tofu Plan PR Comment
uses: ./actions/tf-pr-comment
with:
command: plan
commenter_input: ${{ steps.tofu-plan.outputs.plan-output }}
commenter_exitcode: ${{ steps.tofu-plan.outputs.exitcode }}
env:
PR_NUMBER: ${{ needs.check-and-create-pr.outputs.pr_number }}
PR_COMMENTS_URL: ${{ needs.check-and-create-pr.outputs.pr_comments_url }}
PR_COMMENT_URI: ${{ needs.check-and-create-pr.outputs.pr_comment_uri }}
GITHUB_TOKEN: ${{ secrets.BOT_GITHUB_TOKEN }}
Notes
- For fmt, it is recommended to pass a newline-separated list of files from a previous step to properly generate per-file diffs.
- The action automatically creates or updates PR comments, so duplicate comments are avoided.
- Diff syntax highlighting works on GitHub. On Gitea, diffs are shown in plain text.