infracost.yml

name: 'Run Infracost'
on:
  pull_request:
    types: [opened, synchronize, closed]
jobs:
  infracost-pull-request-checks:
    name: Infracost Pull Request Checks
    if: github.event_name == 'pull_request' && (github.event.action == 'opened' || github.event.action == 'synchronize')
    runs-on: ubuntu-latest
    environment: production
    permissions:
      contents: read
      pull-requests: write # Required to post comments
    steps:
      - name: Setup Infracost
        uses: infracost/actions/setup@v3
        with:
          api-key: ${{ secrets.INFRACOST_API_KEY }}
      # Checkout the base branch of the pull request (e.g. main/master).
      - name: Checkout base branch
        uses: actions/checkout@v4
        with:
          ref: '${{ github.event.pull_request.base.ref }}'
      # Generate Infracost JSON file as the baseline.
      - name: Generate Infracost cost estimate baseline
        run: |
          infracost breakdown --path=. \
                              --format=json \
                              --out-file=/tmp/infracost-base.json
      # Checkout the current PR branch so we can create a diff.
      - name: Checkout PR branch
        uses: actions/checkout@v4
      # Generate an Infracost diff and save it to a JSON file.
      - name: Generate Infracost diff
        run: |
          infracost diff --path=. \
                          --format=json \
                          --compare-to=/tmp/infracost-base.json \
                          --out-file=/tmp/infracost.json
      - name: Post Infracost comment
        run: |
            infracost comment github --path=/tmp/infracost.json \
                                     --repo=$GITHUB_REPOSITORY \
                                     --github-token=${{ github.token }} \
                                     --pull-request=${{ github.event.pull_request.number }} \
                                     --behavior=update \
                                     --policy-path ./policies/cost.rego