create-publish-docker-image.yml

name: Create and publish a Docker image
on:
  push:
    tags:
      - 'v[0-9]+.[0-9]+.[0-9]+'

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}/hytky

jobs:
  build-and-push-image:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Get current branch and exit if not main
        run: |
          raw=$(git branch -r --contains ${{ github.ref }})
          branch=${raw##*/}
          echo "{name}=branch" >> $GITHUB_OUTPUT
          echo "Branch is $branch."
          if [ "$branch" != "main" ]; then
            echo "Not on main branch, exiting."
            exit 0
          fi

      - name: Log in to the Container registry
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      - name: Build and push Docker image
        uses: docker/build-push-action@v5
        with:
          push: true
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          file: docker/Dockerfile.prod
          secrets: | # pass insensitive buildtime variables to docker
            "NEXT_PUBLIC_TG_BOT_NAME=${{ vars.NEXT_PUBLIC_TG_BOT_NAME }}"