hotfix-release-branches.yml

# This workflow is intended to be manually triggered via the GitHub Action tab.
# Given a hotfix branch, it will attempt to open a PR to all release branches and
# by default auto merge them

name: Hotfix release branches

on:
  workflow_dispatch:
    inputs:
      hotfix_commit:
        description: 'Hotfix commit hash'
        required: true
      hotfix_suffix:
        description: 'Hotfix branch suffix (e.g. hotfix/v0.8-{suffix})'
        required: true
      release_branch_pattern:
        description: 'Release branch pattern (regex)'
        required: true
        default: 'release/.*'
      auto_merge:
        description: 'Automatically merge the hotfix PRs'
        required: true
        type: choice
        default: 'true'
        options:
          - true
          - false
          
jobs:
  hotfix_release_branches:
    permissions: write-all
    # See https://runs-on.com/runners/linux/
    # use a lower powered instance since this just does i/o to docker hub
    runs-on: [runs-on,runner=2cpu-linux-x64,"run-id=${{ github.run_id }}"]
    steps:
    
      # needs RKUO_DEPLOY_KEY for write access to merge PR's
      - name: Checkout Repository
        uses: actions/checkout@v4
        with:
          ssh-key: "${{ secrets.RKUO_DEPLOY_KEY }}"
          fetch-depth: 0
          
      - name: Set up Git user
        run: |
          git config user.name "Richard Kuo [bot]"
          git config user.email "rkuo[bot]@danswer.ai"

      - name: Fetch All Branches
        run: |
          git fetch --all --prune

      - name: Verify Hotfix Commit Exists
        run: |
          git rev-parse --verify "${{ github.event.inputs.hotfix_commit }}" || { echo "Commit not found: ${{ github.event.inputs.hotfix_commit }}"; exit 1; }

      - name: Get Release Branches
        id: get_release_branches
        run: |
          BRANCHES=$(git branch -r | grep -E "${{ github.event.inputs.release_branch_pattern }}" | sed 's|origin/||' | tr -d ' ')
          if [ -z "$BRANCHES" ]; then
            echo "No release branches found matching pattern '${{ github.event.inputs.release_branch_pattern }}'."
            exit 1
          fi
          
          echo "Found release branches:"
          echo "$BRANCHES"
          
          # Join the branches into a single line separated by commas
          BRANCHES_JOINED=$(echo "$BRANCHES" | tr '\n' ',' | sed 's/,$//')

          # Set the branches as an output
          echo "branches=$BRANCHES_JOINED" >> $GITHUB_OUTPUT

      # notes on all the vagaries of wiring up automated PR's
      # https://github.com/peter-evans/create-pull-request/blob/main/docs/concepts-guidelines.md#triggering-further-workflow-runs
      # we must use a custom token for GH_TOKEN to trigger the subsequent PR checks
      - name: Create and Merge Pull Requests to Matching Release Branches
        env:
          HOTFIX_COMMIT: ${{ github.event.inputs.hotfix_commit }}
          HOTFIX_SUFFIX: ${{ github.event.inputs.hotfix_suffix }}
          AUTO_MERGE: ${{ github.event.inputs.auto_merge }}
          GH_TOKEN: ${{ secrets.RKUO_PERSONAL_ACCESS_TOKEN }}
        run: |
          # Get the branches from the previous step
          BRANCHES="${{ steps.get_release_branches.outputs.branches }}"

          # Convert BRANCHES to an array
          IFS=$',' read -ra BRANCH_ARRAY <<< "$BRANCHES"

          # Loop through each release branch and create and merge a PR
          for RELEASE_BRANCH in "${BRANCH_ARRAY[@]}"; do
            echo "Processing $RELEASE_BRANCH..."
            
            # Parse out the release version by removing "release/" from the branch name
            RELEASE_VERSION=${RELEASE_BRANCH#release/}
            echo "Release version parsed: $RELEASE_VERSION"
            
            HOTFIX_BRANCH="hotfix/${RELEASE_VERSION}-${HOTFIX_SUFFIX}"
            echo "Creating PR from $HOTFIX_BRANCH to $RELEASE_BRANCH"

            # Checkout the release branch
            echo "Checking out $RELEASE_BRANCH"
            git checkout "$RELEASE_BRANCH"

            # Create the new hotfix branch
            if git rev-parse --verify "$HOTFIX_BRANCH" >/dev/null 2>&1; then
              echo "Hotfix branch $HOTFIX_BRANCH already exists. Skipping branch creation."
            else
              echo "Branching $RELEASE_BRANCH to $HOTFIX_BRANCH"
              git checkout -b "$HOTFIX_BRANCH"
            fi
            
            # Check if the hotfix commit is a merge commit
            if git rev-list --merges -n 1 "$HOTFIX_COMMIT" >/dev/null 2>&1; then
              # -m 1 uses the target branch as the base (which is what we want)
              echo "Hotfix commit $HOTFIX_COMMIT is a merge commit, using -m 1 for cherry-pick"
              CHERRY_PICK_CMD="git cherry-pick -m 1 $HOTFIX_COMMIT"
            else
              CHERRY_PICK_CMD="git cherry-pick $HOTFIX_COMMIT"
            fi

            # Perform the cherry-pick
            echo "Executing: $CHERRY_PICK_CMD"
            eval "$CHERRY_PICK_CMD"

            if [ $? -ne 0 ]; then
              echo "Cherry-pick failed for $HOTFIX_COMMIT on $HOTFIX_BRANCH. Aborting..."
              git cherry-pick --abort
              continue
            fi

            # Push the hotfix branch to the remote
            echo "Pushing $HOTFIX_BRANCH..."
            git push origin "$HOTFIX_BRANCH"
            echo "Hotfix branch $HOTFIX_BRANCH created and pushed."
            
            # Check if PR already exists
            EXISTING_PR=$(gh pr list --head "$HOTFIX_BRANCH" --base "$RELEASE_BRANCH" --state open --json number --jq '.[0].number')

            if [ -n "$EXISTING_PR" ]; then
              echo "An open PR already exists: #$EXISTING_PR. Skipping..."
              continue
            fi
            
            # Create a new PR and capture the output
            PR_OUTPUT=$(gh pr create --title "Merge $HOTFIX_BRANCH into $RELEASE_BRANCH" \
              --body "Automated PR to merge \`$HOTFIX_BRANCH\` into \`$RELEASE_BRANCH\`." \
              --head "$HOTFIX_BRANCH" --base "$RELEASE_BRANCH")

            # Extract the URL from the output
            PR_URL=$(echo "$PR_OUTPUT" | grep -Eo 'https://github.com/[^ ]+')
            echo "Pull request created: $PR_URL"

            # Extract PR number from URL
            PR_NUMBER=$(basename "$PR_URL")
            echo "Pull request created: $PR_NUMBER"

            if [ "$AUTO_MERGE" == "true" ]; then
              echo "Attempting to merge pull request #$PR_NUMBER"

              # Attempt to merge the PR
              gh pr merge "$PR_NUMBER" --merge --auto --delete-branch

              if [ $? -eq 0 ]; then
                echo "Pull request #$PR_NUMBER merged successfully."
              else
                # Optionally, handle the error or continue
                echo "Failed to merge pull request #$PR_NUMBER."
              fi
            fi
          done