github-workflow-upgrade-cluster-flux.yaml

---
name: 'upgrade-cluster-flux'

on:
  schedule:
    # Every Monday at 3 AM UTC
    - cron: "0 3 * * 1"
  workflow_dispatch:
    inputs:
      environment:
        description: 'Environment to run tests against'
        required: true
        type: choice
        options:
        - dev
        - prod
        default: 'dev'
      open-pull-request:
        description: 'Open pull request? Otherwise, perform dry-run showing current/new manifests difference.'
        required: true
        type: boolean
        default: true
      force-upgrade:
        description: 'Perform upgrade even if there is no newer Flux available.'
        required: true
        type: boolean
        default: false

run-name: 'Upgrade Flux (open-pull-request=${{ inputs.open-pull-request }}) by @${{ github.actor }}'

jobs:
  upgrade-flux:
    runs-on: ubuntu-latest

    permissions:
      contents: write
      pull-requests: write

    steps:
      - uses: actions/checkout@v3
        with:
          token: ${{ secrets.MY_GITHUB_BOT_PAT }}

      - name: Setup Flux CLI
        uses: fluxcd/flux2/action@main
        with:
          token: ${{ secrets.MY_GITHUB_BOT_PAT }}

      - name: Check current Flux version
        id: check_current
        run: |
          VERSION=$(head -n 15 ./cluster/${{ inputs.environment }}/flux-system/gotk-components.yaml | grep "app.kubernetes.io/version:" | tr -s "[:blank:]" | cut -d ":" -f 2 | cut -d "v" -f 2)
          echo "flux_version=$VERSION" >> $GITHUB_OUTPUT
          echo $VERSION

      - name: Check upcoming Flux version
        id: check_upcoming
        run: |
          flux -v

          VERSION="$(flux -v | cut -d ' ' -f 3)"
          echo "flux_version=$VERSION" >> $GITHUB_OUTPUT

          if [[ "${{ steps.check_current.outputs.flux_version }}" == "$VERSION" ]]; then
            echo "::notice ::Upcoming Flux $VERSION is not newer than Flux ${{ steps.check_current.outputs.flux_version }} used to generate current manifests"
          fi

      - name: Update Flux manifests
        id: upgrade
        run: |
          FORCE_FLUX_UPGRADE="${{ inputs.force-upgrade }}"
          if [[ "${FORCE_FLUX_UPGRADE}" == "true" ]]  || [[ "${{ steps.check_current.outputs.flux_version }}" != "${{ steps.check_upcoming.outputs.flux_version }}" ]]; then
            flux install \
              --components-extra=image-reflector-controller,image-automation-controller \
              --export > ./cluster/${{ inputs.environment }}/flux-system/gotk-components.yaml
          fi

          VERSION="$(flux -v | cut -d ' ' -f 3)"
          echo "flux_version=$VERSION" >> $GITHUB_OUTPUT

      - if: ${{ ! inputs.open-pull-request }}
        name: Dump Flux manifests diff
        id: diff
        run: |
          git diff --unified=1 --no-color | head -n 500

      - if: ${{ inputs.open-pull-request }}
        name: Create Pull Request
        uses: peter-evans/create-pull-request@v4
        with:
          token: ${{ secrets.MY_GITHUB_BOT_PAT }}
          branch: update-flux
          delete-branch: true
          commit-message: 'Upgrade Flux ${{ steps.upgrade.outputs.flux_version }} in ${{ inputs.environment }} environment cluster'
          title: '[upgrade] Flux ${{ steps.upgrade.outputs.flux_version }} in ${{ inputs.environment }} environment cluster'
          body: |
            Upgrading to [Flux v${{ steps.upgrade.outputs.flux_version }}](https://github.com/fluxcd/flux2/releases/tag/v${{ steps.upgrade.outputs.flux_version }}) on the **${{ inputs.environment }}** environment of the hosting Kubernetes cluster with automated update of the components manifest.

            ## Tasklist

            1. Upgrade your local installation of Flux to ${{ steps.upgrade.outputs.flux_version }}

                ```
                choco install flux --version=${{ steps.upgrade.outputs.flux_version }}
                ```

            2. Review
            3. Make the pull request "Ready for review" and check the changes are recorded as expected.
            4. Merge the pull request to deploy the upgrade.
            5. Run `flux check` to verify that the controllers have been upgraded on the cluster.

          labels: |
            component/flux
            environment/${{ inputs.environment }}
          assignees: mloskot
          draft: true