feat: custom cache support

README.md

@@ -381,6 +381,28 @@ steps:
     run: flutter build apk
 ```
 
+### Using custom cache actions
+
+If you'd like to use a caching action other than `actions/cache` (the GitHub default), you can provide custom actions like this:
+
+```yaml
+- name: Configure Flutter
+  id: config-flutter
+  uses: subosito/flutter-action@v2
+  with:
+    channel: stable
+    cache: true
+    custom-pub-cache-action: my-organization/actions/repository-scoped-cache@main
+    custom-cache-action: my-organization/actions/global-cache@main
+```
+
+Both custom actions must be drop-in replacements for `actions/cache`: they should accept the same inputs and expose the same outputs.
+
+Notes:
+
+- **custom-pub-cache-action** — Recommended to use a repository-scoped cache action (or narrower) as the cache key incorporates a hash of your project's `pubspec.yaml` files. The default `actions/cache` is repository-scoped and also branch-scoped.
+- **custom-cache-action** — Recommended to use a global-scoped cache action here to increase hit rates across multiple Flutter repositories that use the same Flutter version.
+
 ## Outputs
 
 Use outputs from `flutter-action`:

action.yaml

@@ -54,6 +54,14 @@ inputs:
     description: Git clone source
     required: false
     default: "https://github.com/flutter/flutter.git"
+  custom-cache-action:
+    description: Path to a custom caching action that will be executed for flutter cache instead of the default caching mechanism. It must be a drop-in replacement for actions/cache.
+    required: false
+    default: ""
+  custom-pub-cache-action:
+    description: Path to a custom caching action that will be executed for pub cache instead of the default caching mechanism. It must be a drop-in replacement for actions/cache.
+    required: false
+    default: ""
 
 outputs:
   CHANNEL:
@@ -81,10 +89,10 @@ outputs:
     value: "${{ steps.flutter-action.outputs.GIT_SOURCE }}"
     description: Git source of Flutter SDK repository to clone
   CACHE-HIT:
-    value: "${{ steps.cache-flutter.outputs.cache-hit }}"
+    value: "${{ fromJSON(steps.cache-flutter.outputs.outputs || '{}').cache-hit }}"
     description: "`true` if the flutter cache was a hit"
   PUB-CACHE-HIT:
-    value: "${{ steps.cache-pub.outputs.cache-hit }}"
+    value: "${{ fromJSON(steps.cache-pub.outputs.outputs || '{}').cache-hit }}"
     description: "`true` if the pub cache was a hit"
 
 runs:
@@ -120,19 +128,23 @@ runs:
 
     - name: Cache Flutter
       id: cache-flutter
-      uses: actions/cache@v5
-      if: ${{ inputs.cache == 'true' }}
-      with:
-        path: ${{ steps.flutter-action.outputs.CACHE-PATH }}
-        key: ${{ steps.flutter-action.outputs.CACHE-KEY }}
+      uses: jenseng/dynamic-uses@v1
+      if: ${{ inputs.cache == 'true' || inputs.custom-cache-action != '' }}
+      with:      
+        uses: ${{ inputs.custom-cache-action == '' && 'actions/cache@v5' || inputs.custom-cache-action }}
+        with: |
+          path: ${{ toJSON(steps.flutter-action.outputs.CACHE-PATH) }}
+          key: '${{ steps.flutter-action.outputs.CACHE-KEY }}'
 
     - name: Cache pub dependencies
-      uses: actions/cache@v5
       id: cache-pub
-      if: ${{ (inputs.pub-cache == '' && inputs.cache == 'true') || inputs.pub-cache == 'true' }}
+      if: ${{ ((inputs.pub-cache == '' && inputs.cache == 'true') || inputs.pub-cache == 'true') || inputs.custom-pub-cache-action != '' }}
+      uses: jenseng/dynamic-uses@v1
       with:
-        path: ${{ steps.flutter-action.outputs.PUB-CACHE-PATH }}
-        key: ${{ steps.flutter-action.outputs.PUB-CACHE-KEY }}-${{ hashFiles('**/pubspec.lock') }}
+        uses: ${{ inputs.custom-pub-cache-action == '' && 'actions/cache@v5' || inputs.custom-pub-cache-action }}
+        with: |
+          path: ${{ toJSON(steps.flutter-action.outputs.PUB-CACHE-PATH) }}
+          key: '${{ steps.flutter-action.outputs.PUB-CACHE-KEY }}-${{ hashFiles('**/pubspec.lock') }}'
 
     - name: Run setup script
       shell: bash