GitHub Actions Workflow Configuration

Learn how to configure GitHub Actions workflows for Atmos Pro ordered deployments.


This section assumes you are familiar with GitHub Actions workflows and have already been using them in your organization. If you are new to GitHub Actions, please refer to the GitHub Actions documentation for more information.
To use Atmos Pro with GitHub Actions, you'll first need to Create Workspace and then configure three main workflows:
  1. 1
    Affected Stacks Workflow
  2. 2
    Plan Workflow
  3. 3
    Apply Workflow
Atmos Pro uses a set of GitHub Actions workflows to handle everything from detecting changes to applying infrastructure. Below are real, production-ready examples you can drop into your repo to get started fast.
This workflow determines which stacks are affected by changes in your pull request or push to the main branch.
.github/workflows/atmos-pro-affected-stacks.yaml
name: "👽 Atmos Pro Determine Affected Stacks"
run-name: "👽 Atmos Pro Determine Affected Stacks"
 
# Atmos Pro reacts to events defined in the Atmos stack settings
# and will trigger the appropriate workflows for the given event.
#
# For example, pull requests opened, synchronize, and reopened will trigger plan workflows.
# Whereas pull requests merged will trigger apply workflows
on:
  pull_request:
    types:
      - opened
      - synchronize
      - reopened
      - closed
    branches:
      - main
 
# Avoid conflicting workflow triggers.
# For example, wait to trigger apply until plan has been triggered
concurrency:
  group: "${{ github.ref }}"
  cancel-in-progress: false
 
permissions:
  id-token: write # This is required for requesting the JWT (OIDC) token
  contents: read # This is required for actions/checkout
 
jobs:
  affected:
    name: Trigger Affected Stacks
 
    runs-on:
      - "ubuntu-latest"
 
    # Trigger Atmos Pro for Pull Request plan events and specifically closed PRs that have been merged (not just closed)
    if: github.event.action != 'closed' || (github.event.action == 'closed' && github.event.pull_request.merged == true)
 
    steps:
      - name: Checkout
        # For merged PRs, we will need to checkout the base branch to get the correct base branch SHA.
        # This isn't necessary for other events.
        if: github.event.action == 'closed'
        uses: actions/checkout@v4
        with:
          fetch-depth: 0 # Fetch all history for all branches and tags
 
      # For merged PRs, we want to use 1 previous commit from the base branch SHA
      # This is because by the time this workflow runs, the PR branch has already been merged.
      # It's critical to use the base branch SHA to get the correct changes, not the previous commit from the PR branch.
      - name: Determine previous commit on base branch
        id: get_parent
        if: github.event.action == 'closed'
        shell: bash
        run: |
          # For squash merges, github.event.pull_request.base.sha represents the state of the base branch
          # when the PR was created (or last updated). This may be stale compared to the actual commit
          # on the main branch at the time of the merge. Using 'HEAD~1' after the merge ensures we get
          # the commit that was the tip of main immediately before the squash merge commit was added.
          echo "Merge commit: $(git rev-parse HEAD)"
          PARENT=$(git rev-parse HEAD~1)
          echo "Parent (base) commit: $PARENT"
          echo "merge_commit=$MERGE_COMMIT" >> "$GITHUB_OUTPUT"
          echo "parent_commit=$PARENT" >> "$GITHUB_OUTPUT"
 
      - name: Determine Affected Stacks
        id: affected
        uses: cloudposse/github-action-atmos-affected-stacks@v6
        env:
          ATMOS_PRO_WORKSPACE_ID: ${{ vars.ATMOS_PRO_WORKSPACE_ID }}
        with:
          atmos-version: ${{ vars.ATMOS_VERSION }} # >= 1.180.0
          atmos-config-path: ${{ vars.ATMOS_CONFIG_PATH }}
          atmos-pro-upload: true
          # Compare the head of the PR to the base of the PR if the PR is not merged.
          # If the PR is merged, compare the head of the PR to 1 previous commit on the base branch.
          head-ref: ${{ github.event.pull_request.head.sha }}
          base-ref: ${{ github.event.action == 'closed' && steps.get_parent.outputs.parent_commit || github.event.pull_request.base.sha }}
You've seen how it works—now it's your turn. Connect Atmos Pro to your repo and start deploying like it's 2025.

Ready to get started?

Install the Atmos Pro GitHub App to get started.