docker-image.yml

# File written by GitHub user MayNiklas, newer versions can be found in https://github.com/MayNiklas/github-actions
#
# GitHub action for building docker images through nix build
# Images are getting tagged & pushed to Dockerhub
#
# File location: .github/workflows/docker_image.yml
#
# Create the following GitHub Action secrets:
#
# DOCKER_HUB_USERNAME
# DOCKER_HUB_REPO
# DOCKER_HUB_ACCESS_TOKEN

name: build docker images
on:
  push:
    branches:
      - "main"
    tags:
      - "v*"
  workflow_dispatch:
jobs:
  build-docker:
    strategy:
      matrix:
        arch: [x86_64, aarch64]

    runs-on: ubuntu-latest
    steps:
      # checkout source code from github
      - name: Checkout
        uses: actions/checkout@v4
        with:
          # Nix Flakes doesn't work on shallow clones
          fetch-depth: 0

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          # list of Docker images to use as base name for tags
          images: |
            ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}
          # generate Docker tags based on the following events/attributes
          tags: |
            # set latest tag for default branch
            type=raw,value=latest,enable={{is_default_branch}}
            # set version tag for git tag
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=semver,pattern={{major}}

      # install nix package manager
      # https://github.com/cachix/install-nix-action
      - uses: cachix/install-nix-action@v24
        with:
          nix_path: nixpkgs=channel:nixos-unstable
          # Configure Nix to enable flakes
          extra_nix_config: |
            extra-platforms = aarch64-linux i686-linux

      # check if nix flakes is working
      - run: nix flake check

      # enable qemu for cross-compilation
      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3

      # check if qemu is working
      - name: Test binfmt availability
        run: |
          cat /proc/sys/fs/binfmt_misc/qemu-aarch64

      # build package in this stage
      # -> makes this workflow fail faster
      - name: nix build .#shelly-exporter
        run: |
          nix build .#packages.${{ matrix.arch }}-linux.${{ secrets.DOCKER_HUB_REPO }}

      - name: build docker image
        run: |
          nix build .#packages.${{ matrix.arch }}-linux.docker-image

      - name: set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: load docker image
        run: |
          docker load < result

      - name: show docker images
        run: |
          docker images

      - name: execute docker image
        run: |
          docker run --rm ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:latest shelly-exporter -h

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_HUB_USERNAME }}
          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}

      - name: push docker image
        run: |
          docker tag ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:latest ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:${{ matrix.arch }}-latest
          docker push ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:${{ matrix.arch }}-latest

  manifest-create:
    needs: [build-docker]
    runs-on: ubuntu-latest
    steps:
      - name: set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_HUB_USERNAME }}
          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}

      - name: create manifest
        run: |
          docker manifest create \
          "${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:latest" \
          --amend ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:x86_64-latest \
          --amend ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:aarch64-latest

      - name: push manifest
        run: |
          docker manifest push "${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:latest"

  tag-images:
    needs: [build-docker]
    runs-on: ubuntu-latest
    if: startsWith(github.ref, 'refs/tags/v')
    steps:
      - name: set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Set output
        id: vars
        run: echo ::set-output name=tag::${GITHUB_REF#refs/*/}

      - name: create manifest
        run: |
          docker manifest create \
          ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:${{ steps.vars.outputs.tag }} \
          --amend ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:x86_64-latest \
          --amend ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:aarch64-latest

      - name: push manifest
        run: |
          docker manifest push ${{ secrets.DOCKER_HUB_USERNAME }}/${{ secrets.DOCKER_HUB_REPO }}:${{ steps.vars.outputs.tag }}