feat: Cache CI-built cloud-provider-kind Docker image (#84)

.github/actions/cache-cloud-provider-kind-image/action.yml

@@ -0,0 +1,44 @@
+name: Cache cloud-provider-kind image
+description: Checks out, builds, and caches the cloud-provider-kind image
+
+runs:
+  using: composite
+  steps:
+    - name: Checkout cloud-provider-kind repo
+      uses: actions/checkout@v4
+      with:
+        repository: kubernetes-sigs/cloud-provider-kind
+        path: cloud-provider-kind
+
+    - name: Generate cloud-provider-kind image cache key
+      id: cloud-provider-kind-cache-key
+      shell: bash
+      run: echo "hash=$(cd cloud-provider-kind && git rev-parse HEAD)" >> $GITHUB_OUTPUT
+
+    - name: Cache cloud-provider-kind image
+      id: cloud-provider-kind-cache
+      uses: actions/cache@v3
+      with:
+        path: /tmp/cloud-provider-kind-image
+        key: cloud-provider-kind-${{ steps.cloud-provider-kind-cache-key.outputs.hash }}
+
+    - name: Load cached image
+      if: steps.cloud-provider-kind-cache.outputs.cache-hit == 'true'
+      shell: bash
+      run: docker load < /tmp/cloud-provider-kind-image
+
+    - name: Set up Docker Buildx
+      if: steps.cloud-provider-kind-cache.outputs.cache-hit != 'true'
+      uses: docker/setup-buildx-action@v3
+
+    - name: Build cloud-provider-kind image
+      if: steps.cloud-provider-kind-cache.outputs.cache-hit != 'true'
+      uses: docker/build-push-action@v6
+      with:
+        context: ./cloud-provider-kind
+        push: false
+        tags: cloud-provider-kind-cloud-provider:latest
+        load: true
+        cache-from: type=gha
+        cache-to: type=gha,mode=max
+        outputs: type=docker,dest=/tmp/cloud-provider-kind-image

.github/workflows/integration.yml

@@ -1,10 +1,10 @@
----
 name: integration
 on:
   push:
     branches:
       - main
   pull_request:
+
 jobs:
   single-trust-zone:
     name: single trust zone
@@ -24,6 +24,9 @@ jobs:
       - name: Build and run tests
         run: just build
 
+      - name: Build and cache cloud-provider-kind image
+        uses: ./.github/actions/cache-cloud-provider-kind-image
+
       - name: Install kind
         run: just install-kind
 
@@ -62,6 +65,9 @@ jobs:
       - name: Build and run tests
         run: just build
 
+      - name: Build and cache cloud-provider-kind image
+        uses: ./.github/actions/cache-cloud-provider-kind-image
+
       - name: Build and install test plugin
         run: just install-test-plugin
         if: ${{ matrix.plugin == 'cofidectl-test-plugin' }}