tofu-fmt-check action

This is one of a suite of OpenTofu related actions - find them at dflook/terraform-github-actions.

This action uses the tofu fmt command to check that all files in an OpenTofu configuration directory are in the canonical format. This can be used to check that files are properly formatted before merging.

If any files are not correctly formatted a failing GitHub check will be added for the file, and the job failed.

Inputs

path

Path containing OpenTofu files
- Type: string
- Optional
- Default: The action workspace
workspace

OpenTofu workspace to inspect when discovering the OpenTofu version to use, if not otherwise specified. See dflook/tofu-version for details.
- Type: string
- Optional
backend_config

List of OpenTofu backend config values, one per line. This is used for discovering the OpenTofu version to use, if not otherwise specified. See dflook/tofu-version for details.
```
with:
  backend_config: token=${{ secrets.BACKEND_TOKEN }}
```
- Type: string
- Optional
backend_config_file

List of OpenTofu backend config files to use, one per line. This is used for discovering the OpenTofu version to use, if not otherwise specified. See dflook/tofu-version for details. Paths should be relative to the GitHub Actions workspace
```
with:
  backend_config_file: prod.backend.tfvars
```
- Type: string
- Optional

Outputs

failure-reason

When the job outcome is failure because the format check failed, this will be set to 'check-failed'. If the job fails for any other reason this will not be set. This can be used with the Actions expression syntax to conditionally run a step when the format check fails.

Environment Variables

TERRAFORM_CLOUD_TOKENS

For the purpose of detecting the OpenTofu version to use from a cloud backend. API tokens for cloud hosts, of the form <host>=<token>. Multiple tokens may be specified, one per line. These tokens may be used with the remote backend and for fetching required modules from the registry.

e.g:
```
env:
  TERRAFORM_CLOUD_TOKENS: app.terraform.io=${{ secrets.TF_CLOUD_TOKEN }}
```
With other registries:
```
env:
  TERRAFORM_CLOUD_TOKENS: |
    app.terraform.io=${{ secrets.TF_CLOUD_TOKEN }}
    tofu.example.com=${{ secrets.TF_REGISTRY_TOKEN }}
```
- Type: string
- Optional

Example usage

This example workflow runs on every push and fails if any of the OpenTofu files are not formatted correctly.

name: Check file formatting

on: [push]

jobs:
  check_format:
    runs-on: ubuntu-latest
    name: Check OpenTofu file are formatted correctly
    steps:
      - name: Checkout
        uses: actions/checkout@v3

      - name: tofu fmt
        uses: dflook/tofu-fmt-check@v1
        with:
          path: my-terraform-config

This example executes a run step only if the format check failed.

name: Check file formatting

on: [push]

jobs:
  check_format:
    runs-on: ubuntu-latest
    name: Check OpenTofu file are formatted correctly
    steps:
      - name: Checkout
        uses: actions/checkout@v3

      - name: tofu fmt
        uses: dflook/tofu-fmt-check@v1
        id: fmt-check
        with:
          path: my-terraform-config

      - name: Wrong formatting found
        if: ${{ failure() && steps.fmt-check.outputs.failure-reason == 'check-failed' }}
        run: echo "formatting check failed"