test.yml: use a digest of image in template as key for cache

This should reduce the cache size used by the CI.

Signed-off-by: Norio Nomura <norio.nomura@gmail.com>

Author: norio-nomura

.github/actions/setup_cache_for_template/action.yml

@@ -0,0 +1,60 @@
+name: 'setup cache for template'
+description: 'setup cache for template'
+inputs:
+  arch:
+    description: arch to setup cache for
+    required: false
+  template:
+    description: template yaml file
+    required: true
+runs:
+  using: "composite"
+  steps:
+  - name: "detect platform for download directory"
+    id: detect-platform
+    run: |
+      if [[ "$(uname)" == "Darwin" ]]; then
+        download_dir=~/Library/Caches/lima/download
+      else
+        download_dir=~/.cache/lima/download
+      fi
+      echo "download-dir=$download_dir" >> "$GITHUB_OUTPUT"
+    shell: bash
+  - name: "extract key from template"
+    if: always()
+    id: extract-key-from-template
+    run: |
+      set -eux
+      arch="${{ inputs.arch }}"
+      template="${{ inputs.template }}"
+      test -f "$template" || exit 1
+      # detect arch from template if not provided
+      arch="${arch:-$(yq '.arch // ""' "$template")}"
+      arch="${arch:-$(uname -m)}"
+      # normalize arch. amd64 -> x86_64, arm64 -> aarch64
+      case "$arch" in
+        amd64) arch=x86_64 ;;
+        arm64) arch=aarch64 ;;
+      esac
+      # extract digest from template using arch
+      digest="$(yq ".images | map(select(.arch == \"$arch\")) | .[0].digest // \"\"" "$template")"
+      # fallback to os and hash of template file if digest not found
+      key="${digest:+image-$digest}"
+      key="${key:-${{ runner.os }}-${{ hashFiles(inputs.template) }}}"
+      echo "key=$key" >> "$GITHUB_OUTPUT"
+    shell: bash
+  - name: "Cache .download"
+    # avoid using `~` in path that will be expanded to platform specific home directory
+    uses: actions/cache@v4
+    with:
+      path: .download
+      key: ${{ steps.extract-key-from-template.outputs.key }}
+      enableCrossOsArchive: true
+  - name: "Create symbolic link named ${{ steps.detect-platform.outputs.download-dir }} pointing to .download"
+    run: |
+      set -eux
+      [ -d .download ] || mkdir -p .download
+      path_to_cache=${{ steps.detect-platform.outputs.download-dir }}
+      mkdir -p $(dirname $path_to_cache)
+      ln -sfn $PWD/.download $path_to_cache
+    shell: bash

.github/workflows/test.yml

@@ -157,12 +157,10 @@ jobs:
     - uses: actions/setup-go@v5
       with:
         go-version: 1.22.x
-    - name: Cache ~/Library/Caches/lima/download
-      uses: actions/cache@v4
+    - name: Cache image used by default.yaml
+      uses: ./.github/actions/setup_cache_for_template
       with:
-        path: ~/Library/Caches/lima/download
-        # hashFiles do not seem to support symlinks
-        key: ${{ runner.os }}-${{ hashFiles('templates/default.yaml') }}
+        template: templates/default.yaml
     - name: Unit tests
       run: go test -v ./...
     - name: Make
@@ -225,15 +223,14 @@ jobs:
     - uses: actions/setup-go@v5
       with:
         go-version: 1.22.x
-    - id: path_for_hashFiles
-      # It seems that `hashFiles` cannot use `..` as a path component, so generate a normalized path here.
-      run: echo "NORMALIZED=$(realpath --relative-to=$PWD examples/${{ matrix.template }})" >> "$GITHUB_OUTPUT"
-    - uses: actions/cache@v4
+    - name: normalize template path
+      id: normalize_template_path
+      # `hashFiles` cannot use `..` as a path component, so generate a normalized path here.
+      run: echo "NORMALIZED=$(realpath templates/${{ matrix.template }})" >> "$GITHUB_OUTPUT"
+    - name: Cache image used by ${{ steps.normalize_template_path.outputs.NORMALIZED }}
+      uses: ./.github/actions/setup_cache_for_template
       with:
-        path: ~/.cache/lima/download
-        # hashFiles do not seem to support symlinks
-        # TODO: more fine-grained cache
-        key: ${{ runner.os }}-${{ hashFiles(steps.path_for_hashFiles.outputs.NORMALIZED) }}
+        template: ${{ steps.normalize_template_path.outputs.NORMALIZED }}
     - name: Make
       run: make
     - name: Install
@@ -322,12 +319,10 @@ jobs:
     - uses: actions/setup-go@v5
       with:
         go-version: 1.22.x
-    - name: Cache ~/Library/Caches/lima/download
-      uses: actions/cache@v4
+    - name: Cache image used by vmnet.yaml
+      uses: ./.github/actions/setup_cache_for_template
       with:
-        path: ~/Library/Caches/lima/download
-        # hashFiles do not seem to support symlinks
-        key: ${{ runner.os }}-${{ hashFiles('examples/vmnet.yaml') }}
+        template: templates/vmnet.yaml
     - name: Make
       run: make
     - name: Install
@@ -404,15 +399,14 @@ jobs:
     - uses: actions/setup-go@v5
       with:
         go-version: 1.22.x
-    - id: path_for_hashFiles
-      # It seems that `hashFiles` cannot use `..` as a path component, so generate a normalized path here.
-      run: echo "NORMALIZED=$(realpath examples/${{ matrix.template }})" >> "$GITHUB_OUTPUT"
-    - name: Cache ~/Library/Caches/lima/download
-      uses: actions/cache@v4
+    - name: normalize template path
+      id: normalize_template_path
+      # `hashFiles` cannot use `..` as a path component, so generate a normalized path here.
+      run: echo "NORMALIZED=$(realpath templates/${{ matrix.template }})" >> "$GITHUB_OUTPUT"
+    - name: Cache image used by ${{ steps.normalize_template_path.outputs.NORMALIZED }}
+      uses: ./.github/actions/setup_cache_for_template
       with:
-        path: ~/Library/Caches/lima/download
-        # hashFiles do not seem to support symlinks
-        key: ${{ runner.os }}-${{ hashFiles(steps.path_for_hashFiles.outputs.NORMALIZED) }}
+        template: ${{ steps.normalize_template_path.outputs.NORMALIZED }}
     - name: Make
       run: make
     - name: Install

hack/debug-cache.sh

@@ -4,7 +4,7 @@ cache_dir="${HOME}/Library/Caches"
 if [ "$(uname -s)" != "Darwin" ]; then
 	cache_dir="${HOME}/.cache"
 fi
-if [ ! -e "${cache_dir}/lima" ]; then
+if [ ! -e "${cache_dir}/lima/download/by-url-sha256" ]; then
 	echo "No cache"
 	exit 0
 fi