build-and-push.yml

name: Generate development build

# Don't generate builds for other builds!
on:
  push:
    branches-ignore:
      - "builds/**"

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v1

    - name: Install dependencies
      run: |
        npm ci

    - name: Build Typescript
      run: |
        npm run build

    - name: Push build artifacts
      env:
        DEPLOY_KEY: ${{ secrets.DEPLOY_KEY }}
      run: |
        # Find current branch name from GITHUB_REF and prepend 'builds/''
        BUILDS_BRANCH_NAME="builds/${GITHUB_REF#refs/heads/}"
        echo "Pushing artifacts to branch $BUILDS_BRANCH_NAME"

        # Create another clone of the repository in a temporary directory
        git clone "$(git remote get-url origin)" .temp
        cd .temp

        # Checkout the builds branch, or create one if it doesn't exist yet
        git checkout "$BUILDS_BRANCH_NAME" || git checkout --orphan "$BUILDS_BRANCH_NAME"

        # When creating a new branch, the whole working directory is added by
        # default, but we don't want that
        git reset

        # We also have to pull changes from the remote if possible
        git pull || true

        # Move build artifacts and metadata into this new directory, including
        # files always included in npm packages per
        # https://docs.npmjs.com/files/package.json#files
        cp -r ../dist .
        cp ../package.json .
        cp ../LICENSE .
        cp ../README.md .

        # If we have changes...
        if [ -n "$(git status --porcelain)" ]; then

          # Add files to git
          git add -f dist/** package.json LICENSE README.md

          # Commit
          git config user.name "Build Bot"
          git config user.email "bot@github-actions"
          git commit -m "Build of ${GITHUB_SHA:0:7}"

          # Convert remote URL from HTTPS to SSH format so we can use our key
          git remote set-url origin "$(git remote get-url origin | sed 's#http.*com/#git@github.com:#g')"

          # Push the commit to the origin
          eval `ssh-agent -t 60 -s`
          echo "$DEPLOY_KEY" | ssh-add -
          mkdir -p ~/.ssh/
          ssh-keyscan github.com >> ~/.ssh/known_hosts
          git push || git push --set-upstream origin "$BUILDS_BRANCH_NAME"
          ssh-agent -k
        else
          echo "No changes to build output detected"
        fi