action.yml

name: Kernel Builds VM
description: Bootstraps a Lima instance with the selected Linux kernel version
  for building and testing kernel modules.
author: Antoine Cotten (@antoineco)
branding:
  icon: terminal
  color: blue
inputs:
  kernel:
    description: Desired kernel version, in semantic format.
    required: true
  os:
    description: Version code of the Fedora Linux release.
    default: f38
outputs:
  kernel:
    description: Full version string of the running kernel.
    value: ${{ steps.kernel-current.outputs.version }}
  kernel-short:
    description: Short, SemVer compatible version string of the running kernel.
    value: ${{ steps.kernel-current.outputs.version-short }}
  logs:
    description: Location on the runner of the exported cloud-init logs.
    value: ${{ steps.export-logs.outputs.path }}
runs:
  using: composite
  steps:
    - id: validate-input
      shell: bash
      run: |
        echo '::group::Validate input parameters'
        declare err
        declare -i failed=0
        if [[ ! ${{ inputs.kernel }} =~ ^[0-9]\.[0-9]+$ ]]; then
          (( failed ++ ))
          err="The provided 'kernel' parameter '${{ inputs.kernel }}' doesn't match the expected format"
          echo "::error title=Invalid input::${err}"
        fi
        declare os=${{ inputs.os }}
        if [[ -n "$os" && ! "$os" =~ ^f[0-9]{2}$ ]]; then
          (( failed ++ ))
          err="The provided 'os' parameter '${{ inputs.os }}' doesn't match the expected format"
          echo "::error title=Invalid input::${err}"
        fi
        if (( failed )); then
          exit 1
        fi
        echo 'Input OK'
        echo '::endgroup::'
    - id: image
      uses: antoineco/fedora-qemu-img-info-action@v1
      with:
        os: ${{ !inputs.os && 'f38' || inputs.os }}
    - id: gen-vm-name
      shell: bash
      run: |
        echo '::group::Generate Lima instance name'
        declare name="${GITHUB_ACTION#__}-${RANDOM}"
        echo "Exporting Lima instance name '${name}'"
        echo "LIMA_INSTANCE=${name}" >>"$GITHUB_ENV"
        echo '::endgroup::'
    - id: bootstrap
      uses: pyTooling/Actions/with-post-step@v0.4.5
      with:
        # with-post-step executes the given commands using child_process.spawn() with shell=true.
        # On macOS 12, /bin/sh defaults to Bash 3.2, which is too old to run these scripts. We use 'exec' to replace the
        # /bin/sh process with the shell defined by the script's shebang.
        # Ref. https://nodejs.org/docs/latest-v16.x/api/child_process.html#child_processspawncommand-args-options
        main: >-
          exec ${{ github.action_path }}/scripts/pytooling-bootstrap-main.sh
          ${{ steps.image.outputs.url }}
          ${{ steps.image.outputs.sha256sum }}
          ${{ inputs.kernel }}
          ${{ github.workspace }}
        post: |-
          exec ${{ github.action_path }}/scripts/pytooling-bootstrap-post.sh
    - id: kernel-current
      shell: bash
      run: |
        echo '::group::Read version of running Linux kernel'
        source ${{ github.action_path }}/scripts/lib/host/kernel.sh
        source ${{ github.action_path }}/scripts/lib/host/util.sh
        declare arch kernel_current kernel_short
        arch="$(util::linux_arch)"
        kernel_current="$(kernel::current)"
        echo "version=${kernel_current}" >>"$GITHUB_OUTPUT"
        if [[ "$kernel_current" =~ ^([0-9]+\.[0-9]+(\.[0-9]+)?) ]]; then
          kernel_short="${BASH_REMATCH[1]}"
          echo "version-short=${kernel_short}" >>"$GITHUB_OUTPUT"
        else
          declare err="Unable to parse short version of running kernel ${kernel_current}"
          echo "::error title=Invalid kernel version::${err}"
          exit 1
        fi
        echo "Lima instance is running kernel '${kernel_current}' (${kernel_short})"
        echo '::endgroup::'
    - id: kernel-semver
      uses: madhead/semver-utils@v3
      with:
        version: ${{ steps.kernel-current.outputs.version-short }}
        satisfies: ${{ inputs.kernel }}.x
        lenient: false
    - id: kernel-check
      shell: bash
      run: |
        echo '::group::Verify kernel version constraint'
        if [[ ${{ steps.kernel-semver.outputs.satisfies }} != 'true' ]]; then
          declare err='Running kernel ${{ steps.kernel-current.outputs.version-short }} does not satisfy constraint ${{ inputs.kernel }}.x'
          echo "::error title=Wrong kernel version::${err}"
          exit 1
        fi
        echo 'Running kernel ${{ steps.kernel-current.outputs.version-short }} satisfies constraint ${{ inputs.kernel }}.x'
        echo '::endgroup::'
    - id: export-logs
      if: always() && steps.gen-vm-name.outcome == 'success' && steps.bootstrap.outcome != 'skipped'
      shell: bash
      run: |
        echo '::group::Export cloud-init logs'
        declare logs_path=/tmp/lima/${{ env.LIMA_INSTANCE }}
        mkdir -p "$logs_path"
        declare unit
        for unit in cloud-init cloud-final; do
          echo "Exporting messages for unit '${unit}.service' to ${logs_path}/${unit}.log"
          lima sudo sh -c "journalctl -u ${unit}.service >${logs_path}/${unit}.log"
        done
        echo "path=${logs_path}" >>"$GITHUB_OUTPUT"
        echo '::endgroup::'