terragrunt-action

A GitHub Action for installing and running Terragrunt

Rationale

This is a forked repo because I had a client looking for aws cli and pip functionality within the Terragrunt container to conform to the structure of many of their existing Terraform scripts.

This fork essentially installs those dependencies and adds a configuration step to the main.sh to configure both AWS and pip

Inputs

Supported GitHub action inputs:

Input Name	Description	Required	Example values
tf_version	Terraform version to be used in Action execution	true	1.4.6
tg_version	Terragrunt version to be user in Action execution	true	0.50.8
tg_dir	Directory in which Terragrunt will be invoked	true	work
tg_command	Terragrunt command to execute	true	plan/apply
tg_comment	Add comment to Pull request with execution output	false	0/1
tg_add_approve	Automatically add "-auto-approve" to commands, enabled by default	false	0/1

Environment Variables

Supported environment variables:

Input Name	Description
GITHUB_TOKEN	GitHub token used to add comment to Pull request
TF_LOG	Log level for Terraform
TF_VAR_name	Define custom variable name as inputs
INPUT_PRE_EXEC_number	Environment variable is utilized to provide custom commands that will be executed before running Terragrunt
INPUT_POST_EXEC_number	Environment variable is utilized to provide custom commands that will be executed after running Terragrunt
AWS_PROFILE_NAME	The name associated with the invocation profile in the Terraform file
AWS_SHARED_CREDENTIALS_FILE	Environment variable is utilized to configure AWS for the Terragrunt invocation
AWS_ACCESS_KEY_ID	AWS Access Key
AWS_SECRET_ACCESS_KEY	AWS Secret Access Key
PIP_CONF_FILE	Location of pip configuration file for use when fetching from private artifactory

Outputs

Outputs of GitHub action:

Input Name	Description
tg_action_exit_code	Terragrunt exit code
tg_action_output	Terragrunt output as plain text

Usage

Example definition of Github Action workflow:

name: 'Terragrunt GitHub Actions'
on:
  - pull_request

env:
  tf_version: '1.5.7'
  tg_version: '0.53.2'
  working_dir: 'project'

jobs:
  checks:
    runs-on: ubuntu-latest
    steps:
      - name: 'Checkout'
        uses: actions/checkout@main

      - name: Check terragrunt HCL
        uses: gruntwork-io/terragrunt-action@v2
        with:
          tf_version: ${{ env.tf_version }}
          tg_version: ${{ env.tg_version }}
          tg_dir: ${{ env.working_dir }}
          tg_command: 'hclfmt --terragrunt-check --terragrunt-diff'

  plan:
    runs-on: ubuntu-latest
    needs: [ checks ]
    steps:
      - name: 'Checkout'
        uses: actions/checkout@main

      - name: Plan
        uses: gruntwork-io/terragrunt-action@v2
        with:
          tf_version: ${{ env.tf_version }}
          tg_version: ${{ env.tg_version }}
          tg_dir: ${{ env.working_dir }}
          tg_command: 'plan'

  deploy:
    runs-on: ubuntu-latest
    needs: [ plan ]
    environment: 'prod'
    if: github.ref == 'refs/heads/main'
    steps:
      - name: 'Checkout'
        uses: actions/checkout@main

      - name: Deploy
        uses: gruntwork-io/terragrunt-action@v2
        with:
          tf_version: ${{ env.tf_version }}
          tg_version: ${{ env.tg_version }}
          tg_dir: ${{ env.working_dir }}
          tg_command: 'apply'

Example of passing custom code before running Terragrunt:

...
- name: Plan
  uses: gruntwork-io/terragrunt-action@v2
  env:
    # configure git to use custom token to clone repository.
    INPUT_PRE_EXEC_1: |
      git config --global url."https://user:${{secrets.PAT_TOKEN}}@github.com".insteadOf "https://github.com"
    # print git configuration
    INPUT_PRE_EXEC_2: |
      git config --global --list
  with:
    tg_command: 'plan'
...