backport.yml

name: Backport Pull Request
on:
  pull_request_target:
    types:
      - closed
      - opened
      - reopened
    branches:
      - main

env:
  GOLANG_VERSION: "1.21.x"

jobs:
  # Label the source pull request with 'backport-requested' and all supported releases label, the goal is, by default
  # we backport everything, except those PR that are created or contain `do not backport` explicitly.
  label-source-pr:
    name: Add labels to PR
    if: | 
        github.event.pull_request.merged == false &&
        !contains(github.event.pull_request.labels.*.name, 'backport-requested') &&
        !contains(github.event.pull_request.labels.*.name, 'do not backport')
    runs-on: ubuntu-22.04
    steps:
      -
        name: Label the pull request
        uses: actions-ecosystem/action-add-labels@v1
        if: ${{ !contains(github.event.pull_request.labels.*.name, 'do not backport') }}
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          number:  ${{ github.event.pull_request.number }}
          labels: |
            backport-requested :arrow_backward:
            release-1.19
            release-1.20
      -
        name: Create comment
        uses: peter-evans/create-or-update-comment@v3
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          issue-number: ${{ github.event.pull_request.number }}
          body: |
            :exclamation: By default, the pull request is configured to backport to all release branches.

            - To stop backporting this pr, remove the label:  backport-requested :arrow_backward: or add the label 'do not backport'
            - To stop backporting this pr to a certain release branch, remove the specific branch label: release-x.y

          reactions: heart
      -
        name: Remove redundant labels
        uses: actions-ecosystem/action-remove-labels@v1
        if: ${{ contains(github.event.pull_request.labels.*.name, 'do not backport') }}
        with:
          labels: |
            backport-requested :arrow_backward:
            release-1.19
            release-1.20

  ## backport pull request in condition when pr contains 'backport-requested' label and contains target branches labels
  back-porting-pr:
    name: Backport to release branches
    if: |
        github.event.pull_request.merged == true &&
        (
          contains(github.event.pull_request.labels.*.name, 'backport-requested') ||
          contains(github.event.pull_request.labels.*.name, 'backport-requested :arrow_backward:')
        ) &&
        !contains(github.event.pull_request.labels.*.name, 'do not backport')
    runs-on: ubuntu-22.04
    strategy:
      fail-fast: false
      matrix:
        branch:
          -  release-1.19
          -  release-1.20
    env:
      PR: ${{ github.event.pull_request.number }}
    outputs:
      commit: ${{ steps.check_commits.outputs.commit }}
    steps:
      -
        name: Checkout code
        if: contains( github.event.pull_request.labels.*.name, matrix.branch )
        uses: actions/checkout@v3
        with:
          fetch-depth: 0
          ref: ${{ matrix.branch }}
          token: ${{ secrets.REPO_GHA_PAT }}
      -
        name: Install Go
        uses: actions/setup-go@v4
        with:
          go-version: ${{ env.GOLANG_VERSION }}
      -
        name: Check commits
        if: contains( github.event.pull_request.labels.*.name, matrix.branch )
        id: check_commits
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          commit=$(gh pr view ${PR} --json mergeCommit -q ".mergeCommit.oid" 2>/dev/null || :)
          if [ -z "${commit}" ]
          then
            echo "No commit found!"
            exit 0
          fi
          echo "commit=${commit}" >> $GITHUB_OUTPUT
          echo "cherry-pick commit ${commit} to branch ${{ matrix.branch }}"
          author_name=$(git show -s --format='%an' "${commit}")
          echo "AUTHOR_NAME=${author_name}" >> $GITHUB_ENV
          author_email=$(git show -s --format='%ae' "${commit}")
          echo "AUTHOR_EMAIL=${author_email}" >> $GITHUB_ENV
      -
        name: cherry pick
        env:
          COMMIT: ${{ steps.check_commits.outputs.commit }}
        if: |
          contains( github.event.pull_request.labels.*.name, matrix.branch ) && env.COMMIT != ''
        run: |
          git config user.email "${{ env.AUTHOR_EMAIL }}"
          git config user.name "${{ env.AUTHOR_NAME }}"
          git fetch
          git cherry-pick -x --mainline 1 ${{ env.COMMIT }}
          make fmt vet generate apidoc wordlist-ordered
          if ! git diff --exit-code --quiet
          then
            echo "!!! Generated files need manually handling"
            exit 1
          fi
          git push

  create-tickets:
    name: Create tickets for failures
    needs:
      - back-porting-pr
    if: |
      failure() && !cancelled() &&
      needs.back-porting-pr.outputs.commit != ''
    env:
      PR: ${{ github.event.pull_request.number }}
      COMMIT: ${{ needs.back-porting-pr.outputs.commit }}
    runs-on: ubuntu-22.04
    steps:
      - name: create ticket
        uses: dacbd/create-issue-action@v1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          title: Backport failure for pull request ${{ env.PR }}
          labels: backport failure
          body: |
            ### Context
            Automatically backport failure for pull request ${{ env.PR }}

            Pull request: ${{ github.server_url }}/${{ github.repository }}/pull/${{ env.PR }}
            Commit: ${{ github.server_url }}/${{ github.repository }}/commit/${{ env.COMMIT }}
            Workflow: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}

            To solve the ticket, open the workflow link above, and for each failed release branch check the following:

            1. Whether the commit should be `cherry-pick`(ed) to this release branch, otherwise skip this release branch
            2. If yes, `cherry-pick` the commit manually and push it to the release branch. You may need to resolve the
            conflicts and issue `cherry-pick --continue` again. Also, a dependent commit missing may be causing the
            failure, so if that's the case you may need to `cherry-pick` the dependent commit first.