git-auto-issue-branch-creation.yml

name: Auto create git branch upon new issue
on:
  issues:
    types: [opened, reopened]

jobs:
  create-issue-branch:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Get issue number and title
        id: issue
        run: |
          echo "::set-output name=number::${{ github.event.issue.number }}"
          echo "::set-output name=title::${{ github.event.issue.title }}"
          # Sanitize issue title to:
          # - alnum
          # - replace spaces with hyphen '-'
          # Example:
          # Given an issue title: "Fix the 2'nd bug in UI where there's a # in the form"
          # Becomes:
          #
                                                             # Note there is a space here, to keep both '-' and spaces ' '
          echo ISSUE_BRANCH_NAME=`echo "${{ github.event.issue.title }}" | \
          # Remove non alpha/numeric chars
          tr -cd '[:alnum:]- ' | \
          # Convert spaces to hyphens '-'
          tr ' ' '-' | \
          # Ensure lowercase branch name
          tr '[:upper:]' '[:lower:]' | \
          # Limit branch name to 60 characters
          cut -c -60` >> $GITHUB_ENV

          ALLOWED_BRANCH_NAME_CHARS='[^a-zA-Z0-9-]'
          # Loop through each character in the branch name, replacing any not allowed characer with a hyphen '-'
          while [[ $ISSUE_BRANCH_NAME =~ $ALLOWED_BRANCH_NAME_CHARS ]]; do
            ISSUE_BRANCH_NAME=`echo $ISSUE_BRANCH_NAME | sed -r "s/($ALLOWED_BRANCH_NAME_CHARS)/-/g" | sed 's/--/-/g'`
          done

          echo $ISSUE_BRANCH_NAME >> $GITHUB_ENV

      - name: Create new branch
        run: |
          echo "The issue branch name is ${{ env.ISSUE_BRANCH_NAME}} "
          git checkout -b "${{ steps.issue.outputs.number }}-${{ env.ISSUE_BRANCH_NAME }}"
          git push -u origin HEAD