stage.yml

name: Stage updates

on:
  push:
    branches:
      u/staging-*

jobs:
  merge:
    name: Stage updates
    runs-on: ubuntu-latest
    steps:
    - name: Stage updates
      env:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        BRANCH_STAGING: u/staging
        NUM_TRIES: 10
        RETRY_SLEEP: 30
      run: |
        repo="https://${GITHUB_ACTOR}:${GITHUB_TOKEN}@github.com/${GITHUB_REPOSITORY}.git"
        branch="${GITHUB_REF#refs/heads/}"

        # set git identity
        git config --global user.email "surfacebot@users.noreply.github.com"
        git config --global user.name "surfacebot"

        # clone source branch
        git clone -b "${branch}" "${repo}" .

        tries=0
        until [ $tries -ge $NUM_TRIES ]; do
            echo "==> Starting attempt $tries/$NUM_TRIES"

            # checkout, reset, and update target branch
            git checkout "${BRANCH_STAGING}"
            git reset --hard "origin/${BRANCH_STAGING}"
            git pull

            # rebase and merge
            git rebase "${BRANCH_STAGING}" "${branch}"
            git checkout "${BRANCH_STAGING}"
            git merge "${branch}"

            # try to push, break on success
            git push && break

            echo "==> Failed to push changes"

            tries=$((tries+1))
            sleep ${RETRY_SLEEP}
        done

        if [ $tries -ge $NUM_TRIES ]; then
            echo "==> Failed to stage updates"
            exit 1
        fi

        # delete branch
        git push origin ":${branch}"