ci: use GitHub Actions Cache

.github/workflows/ci.yml

@@ -58,10 +58,12 @@ jobs:
         # The .ts scripts depend upon this
       - run: yarn global add tsx
 
+      - name: Export vars of Actions Runtime for caching
+        uses: crazy-max/ghaction-github-runtime@v3
+
       - name: build test images
-        run: |
-          docker info
-          ./buildTestImages.ts
+        run: ./buildTestImages.ts --buildOpts="--cache-from type=gha --cache-to type=gha,mode=max"
+
       - name: run test images
         run: ./runTestImages.ts
 
@@ -77,6 +79,10 @@ jobs:
           push: true
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
+          # use GitHub Actions Cache https://github.com/moby/buildkit#github-actions-cache-experimental
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
       - name: notify on failure
         if: failure() && github.event_name != 'pull_request'
         uses: ./.github/actions/notify-status

buildTestImages.ts

@@ -8,12 +8,13 @@ import { refreshDockerfile } from './makeDockerfile';
 refreshDockerfile();
 
 const options = {
+  buildOpts: { type: 'string' },
   match: { short: 'm', type: 'string' },
   dry: { type: 'boolean' },
 } as const;
 const { values } = parseArgs({ options });
 
-const { match, dry } = values;
+const { buildOpts, match, dry } = values;
 
 const allProposals = readProposals();
 
@@ -28,7 +29,7 @@ for (const proposal of proposals) {
   const { name, target } = imageNameForProposalTest(proposal);
   // 'load' to ensure the images are output to the Docker client. Seems to be necessary
   // for the CI docker/build-push-action to re-use the cached stages.
-  const cmd = `docker buildx build --load --tag ${name} --target ${target} .`;
+  const cmd = `docker buildx build ${buildOpts} --load --tag ${name} --target ${target} .`;
   console.log(cmd);
   if (!dry) {
     execSync(cmd, { stdio: 'inherit' });