update-sigmarule.yaml

### If you want to execte GitHub Actions on your local machine please use following commnad. (Please install act if needed.)
### act workflow_dispatch -s GITHUB_TOKEN=(your private access token) -P ubuntu-latest=nektos/act-environments-ubuntu:18.04 --artifact-server-path /tmp/act-artifacts

name: Pipeline for sigma rule updates

on:
  ## This workflow is executed once a day.
  ## I added workflow_dispatch so that you can execute this workflow from the GitHub UI.
  workflow_dispatch:
  schedule:
    - cron: '0 20 * * *'

jobs:
  updateSigmaRule:
    runs-on: ubuntu-latest
    steps:
      - name: clone sigma
        uses: actions/checkout@v4
        with:
          repository: SigmaHQ/sigma
          path: sigma
          token: ${{ secrets.GITHUB_TOKEN }} ## This is necessary for executing on a local machine by act(Local GitHub Action Runner). We have to specify the github token explicitly.

      - name: clone suzaku rule repo
        uses: actions/checkout@v4
        with:
          path: suzaku-rules

      - name: Update sigma rules
        run: |
          rm -rf suzaku-rules/sigma/cloud/aws/
          mv sigma/rules/cloud/aws suzaku-rules/sigma/cloud

      - name: Create Text
        id: create-text
        run: |
          pushd suzaku-rules
          echo "action_date=$(date '+%Y-%m-%d  %H:%M:%S')" >> $GITHUB_ENV
          echo "change_exist=true" >> $GITHUB_ENV
          git_new=$(git diff --name-status --diff-filter=AC)
          git_mod=$(git diff --name-status --diff-filter=MR)
          git_del=$(git diff --name-status --diff-filter=D)
          is_rule_changed=$(git status)
          if [ "${is_rule_changed}" =~ nothing\sto\scommit ]; then
            echo "change_exist=false" >> $GITHUB_ENV
          else
          	echo "<details><summary>New files</summary>" >> ../changed_rule.logs
          	echo "${git_new}" >> ../changed_rule.logs
          	echo "</details>" >> ../changed_rule.logs
          	echo "<details><summary>Modified files</summary>" >> ../changed_rule.logs
          	echo "${git_mod}" >> ../changed_rule.logs
          	echo "</details>" >> ../changed_rule.logs
          	echo "<details><summary>Deleted files</summary>" >> ../changed_rule.logs
          	echo "${git_del}" >> ../changed_rule.logs
          	echo "</details>" >> ../changed_rule.logs
          fi
          popd

      - name: Create Pull Request
        if: env.change_exist == 'true'
        id: cpr
        uses: peter-evans/create-pull-request@v4
        with:
          path: suzaku-rules
          token: ${{ secrets.GITHUB_TOKEN }}
          commit-message: Sigma Rule Update (${{ env.action_date }})
          branch: rules/auto-sigma-update
          delete-branch: true
          title: '[Auto] Sigma Update report(${{ env.action_date }})' ### If a PR with the same name already exists, this github action library will not create a new pull request but it will update the PR with the same name. Therefore I added the date to the pull request's title so it creates a new PR.
          branch-suffix: timestamp ### I use this field in order to avoid name duplication. If the pull request which is related to the same branch exists, the pull request is not newly created but is updated. So the next step will be skipped due to its if-field
          body: |
            ${{ env.action_date }} Update report

      - name: Enable Pull Request Automerge
        if: steps.cpr.outputs.pull-request-operation == 'created' # This only runs if there were sigma rules updates and a new PR was created.
        uses: peter-evans/enable-pull-request-automerge@v3
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          pull-request-number: ${{ steps.cpr.outputs.pull-request-number }}
          merge-method: squash

      - name: Auto approve
        if: steps.cpr.outputs.pull-request-operation == 'created'
        run: gh pr review --approve "${{ steps.cpr.outputs.pull-request-number }}"
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      - name: upload change log
        if: env.change_exist == 'true'
        uses: actions/upload-artifact@v4
        with:
          name: changed_rule_log
          path: ${{ github.workspace }}/changed_rule.logs
          retention-days: 30