feat: kube-hetzner own cluster autoscaler image

.github/workflows/cluster-autoscaler.yaml

@@ -0,0 +1,12 @@
+name: Cluster Autoscaler
+
+on:
+  pull_request:
+
+jobs:
+  build:
+    uses: ./.github/workflows/multi-arch-build.yaml
+    with:
+      image: ghcr.io/kube-hetzner/autoscaler/cluster-autoscaler
+      context: cluster-autoscaler
+      digestName: 'cluster-autoscaler'

.github/workflows/multi-arch-build.yaml

@@ -0,0 +1,108 @@
+on:
+  workflow_call:
+    inputs:
+      image:
+        required: true
+        type: string
+      context:
+        required: true
+        type: string
+      dockerfile:
+        required: false
+        type: string
+        default: ${{ inputs.context }}
+      digestName:
+        required: true
+        type: string
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        platform:
+          - linux/amd64
+          - linux/arm64
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ inputs.image }}
+          tags: |
+            type=raw,value=latest,enable=true
+            type=raw,value={{date 'YYYYMMDD'}},enable=true
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Build and push by digest
+        id: build
+        uses: docker/build-push-action@v5
+        with:
+          build-args: ${{ inputs.buildArgs }}
+          context: ${{ inputs.context }}
+          file: ${{ inputs.dockerfile }}
+          labels: ${{ steps.meta.outputs.labels }}
+          platforms: ${{ matrix.platform }}
+          outputs: type=image,name=${{ inputs.image }},push-by-digest=true,name-canonical=true,push=true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+      - name: Export digest
+        run: |
+          mkdir -p /tmp/digests
+          digest="${{ steps.build.outputs.digest }}"
+          touch "/tmp/digests/${digest#sha256:}"
+      - name: Upload digest
+        uses: actions/upload-artifact@v3
+        with:
+          name: ${{ inputs.digestName }}
+          path: /tmp/digests/*
+          if-no-files-found: error
+          retention-days: 1
+
+  merge:
+    name: Merge and publish
+    runs-on: ubuntu-latest
+    needs:
+      - build
+    steps:
+      - name: Download digests
+        uses: actions/download-artifact@v3
+        with:
+          name: ${{ inputs.digestName }}
+          path: /tmp/digests
+      - uses: geekyeggo/delete-artifact@v2
+        with:
+          name: ${{ inputs.digestName }}
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ inputs.image }}
+          tags: |
+            type=raw,value=latest,enable=true
+            type=raw,value={{date 'YYYYMMDD'}},enable=true
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Create manifest list and push
+        working-directory: /tmp/digests
+        run: |
+          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
+            $(printf '${{ inputs.image }}@sha256:%s ' *)
+      - name: Inspect image
+        run: |
+          docker buildx imagetools inspect ${{ inputs.image }}:${{ steps.meta.outputs.version }}

cluster-autoscaler/Dockerfile

@@ -0,0 +1,12 @@
+FROM golang:1.21 as build
+
+WORKDIR /app
+
+COPY . .
+RUN go build -v -o /usr/local/bin/app
+
+FROM golang:1.21
+
+COPY --from=build /usr/local/bin/app /usr/local/bin/app
+
+CMD ["app"]