Utilize GitHub Actions cache for image builds

.github/workflows/release.yml

@@ -13,8 +13,53 @@ on:
     - main
 
 jobs:
+  build-cache:
+    strategy:
+      matrix:
+        arch:
+          - amd64
+          - arm64
+          - ppc64le
+          - s390x
+        platform: [linux]
+    runs-on: ubuntu-latest
+    steps:
+    - name: Check out code into the Go module directory
+      uses: actions/checkout@v3
+      with:
+        fetch-depth: 0
+
+    - name: Install Go
+      uses: actions/setup-go@v4
+      with:
+        go-version-file: "go.mod"
+
+    - name: Set up QEMU
+      uses: docker/setup-qemu-action@v2
+
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+      # The Dockerfile expects that ansible-operator will be copied from the
+      # build context. We stub it here and then don't cache it. When Goreleaser
+      # runs, it should copy over the right file.
+    - name: Create ansible-operator stub
+      run: echo stubbed-in-ci >> ansible-operator
+
+    - name: Build
+      uses: docker/build-push-action@v6
+      with:
+        context: .
+        platforms: "${{ matrix.platform }}/${{ matrix.arch }}"
+        push: false
+        tags: "cache:${{ matrix.platform }}-${{ matrix.arch }}"
+        file: images/ansible-operator/Dockerfile
+        cache-from: type=gha,scope=${{ matrix.arch }}
+        cache-to: type=gha,mode=max,scope=${{ matrix.arch }}
+        no-cache-filters: final # don't cache this because the stubbed ansible-operator bin was copied in.
+
   goreleaser:
-    name: goreleaser
+    needs: [build-cache]
     runs-on: ubuntu-latest
     steps:
     - name: Check out code into the Go module directory
@@ -38,6 +83,10 @@ jobs:
     - name: Set up QEMU
       uses: docker/setup-qemu-action@v2
 
+    - name: Set up Docker Buildx
+      id: setup-buildx
+      uses: docker/setup-buildx-action@v3
+
     - name: Set the release related variables
       run: |
         if [[ $GITHUB_REF == refs/tags/* ]]; then
@@ -56,7 +105,13 @@ jobs:
           echo IMAGE_TAG="$(git describe --tags --always)" >> $GITHUB_ENV
         fi
 
+      # This gives us ACTIONS_RUNTIME_TOKEN and ACTIONS_CACHE_URL
+      # for use in goreleaser
+    - name: Expose GitHub Runtime
+      uses: crazy-max/ghaction-github-runtime@v3
+
     - name: Run goreleaser
       run: make release
       env:
         GITHUB_TOKEN: ${{ github.token }}
+        BUILDX_BUILDER: ${{ steps.setup-buildx.outputs.name }}

.goreleaser.yml

@@ -26,6 +26,9 @@ dockers:
   use: buildx
   build_flag_templates:
     - "--platform=linux/amd64"
+    - "--cache-from"
+    - "type=gha,scope=amd64,token={{ .Env.ACTIONS_RUNTIME_TOKEN }},url={{ .Env.ACTIONS_CACHE_URL }}"
+    - "--builder={{ .Env.BUILDX_BUILDER }}"
   extra_files:
     - "images/ansible-operator/Pipfile"
     - "images/ansible-operator/Pipfile.lock"
@@ -37,6 +40,9 @@ dockers:
   use: buildx
   build_flag_templates:
     - "--platform=linux/arm64"
+    - "--cache-from"
+    - "type=gha,scope=arm64,token={{ .Env.ACTIONS_RUNTIME_TOKEN }},url={{ .Env.ACTIONS_CACHE_URL }}"
+    - "--builder={{ .Env.BUILDX_BUILDER }}"
   extra_files:
     - "images/ansible-operator/Pipfile"
     - "images/ansible-operator/Pipfile.lock"
@@ -48,6 +54,9 @@ dockers:
   use: buildx
   build_flag_templates:
     - "--platform=linux/ppc64le"
+    - "--cache-from"
+    - "type=gha,scope=ppc64le,token={{ .Env.ACTIONS_RUNTIME_TOKEN }},url={{ .Env.ACTIONS_CACHE_URL }}"
+    - "--builder={{ .Env.BUILDX_BUILDER }}"
   extra_files:
     - "images/ansible-operator/Pipfile"
     - "images/ansible-operator/Pipfile.lock"
@@ -59,6 +68,9 @@ dockers:
   use: buildx
   build_flag_templates:
     - "--platform=linux/s390x"
+    - "--cache-from"
+    - "type=gha,scope=s390x,token={{ .Env.ACTIONS_RUNTIME_TOKEN }},url={{ .Env.ACTIONS_CACHE_URL }}"
+    - "--builder={{ .Env.BUILDX_BUILDER }}"
   extra_files:
     - "images/ansible-operator/Pipfile"
     - "images/ansible-operator/Pipfile.lock"

images/ansible-operator/Dockerfile

@@ -40,7 +40,7 @@ RUN set -e && dnf clean all && rm -rf /var/cache/dnf/* \
   && dnf clean all \
   && rm -rf /var/cache/dnf
 
-FROM registry.access.redhat.com/ubi9/ubi:9.4-1214.1726694543 as base
+FROM registry.access.redhat.com/ubi9/ubi:9.4-1214.1726694543 AS base
 ARG TARGETARCH
 
 # Label this image with the repo and commit that built it, for freshmaking purposes.
@@ -68,7 +68,7 @@ RUN curl -L -o /tini https://github.com/krallin/tini/releases/download/${TINI_VE
   && chmod +x /tini && /tini --version
 
 # Final image.
-FROM base
+FROM base AS final
 
 ENV HOME=/opt/ansible \
     USER_NAME=ansible \