cache-image input to enable/disable caching of binfmt image

.github/workflows/ci.yml

@@ -65,3 +65,26 @@ jobs:
             echo "::error::Should have failed"
             exit 1
           fi
+
+  cache-image:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        cache:
+          - true
+          - false
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v4
+      -
+        name: Set up QEMU
+        id: qemu
+        uses: ./
+        with:
+          image: tonistiigi/binfmt:master
+          cache-image: ${{ matrix.cache }}
+      -
+        name: Available platforms
+        run: echo ${{ steps.qemu.outputs.platforms }}

README.md

@@ -41,10 +41,11 @@ jobs:
 
 The following inputs can be used as `step.with` keys:
 
-| Name        | Type   | Default                                                                       | Description                                      |
-|-------------|--------|-------------------------------------------------------------------------------|--------------------------------------------------|
-| `image`     | String | [`tonistiigi/binfmt:latest`](https://hub.docker.com/r/tonistiigi/binfmt/tags) | QEMU static binaries Docker image                |
-| `platforms` | String | `all`                                                                         | Platforms to install (e.g., `arm64,riscv64,arm`) |
+| Name          | Type   | Default                                                                       | Description                                        |
+|---------------|--------|-------------------------------------------------------------------------------|----------------------------------------------------|
+| `image`       | String | [`tonistiigi/binfmt:latest`](https://hub.docker.com/r/tonistiigi/binfmt/tags) | QEMU static binaries Docker image                  |
+| `platforms`   | String | `all`                                                                         | Platforms to install (e.g., `arm64,riscv64,arm`)   |
+| `cache-image` | Bool   | `true`                                                                        | Cache binfmt image to GitHub Actions cache backend |
 
 ### outputs
 

__tests__/context.test.ts

@@ -16,31 +16,38 @@ describe('getInputs', () => {
   test.each([
     [
       0,
-      new Map<string, string>([]),
+      new Map<string, string>([
+        ['cache-image', 'true'],
+      ]),
       {
         image: 'tonistiigi/binfmt:latest',
         platforms: 'all',
+        cacheImage: true,
       } as context.Inputs
     ],
     [
       1,
       new Map<string, string>([
         ['image', 'docker/binfmt:latest'],
         ['platforms', 'arm64,riscv64,arm'],
+        ['cache-image', 'false'],
       ]),
       {
         image: 'docker/binfmt:latest',
         platforms: 'arm64,riscv64,arm',
+        cacheImage: false,
       } as context.Inputs
     ],
     [
       2,
       new Map<string, string>([
         ['platforms', 'arm64, riscv64, arm '],
+        ['cache-image', 'true'],
       ]),
       {
         image: 'tonistiigi/binfmt:latest',
         platforms: 'arm64,riscv64,arm',
+        cacheImage: true,
       } as context.Inputs
     ]
   ])(

action.yml

@@ -15,6 +15,10 @@ inputs:
     description: 'Platforms to install (e.g. arm64,riscv64,arm)'
     default: 'all'
     required: false
+  cache-image:
+    description: 'Cache binfmt image to GitHub Actions cache backend'
+    default: 'true'
+    required: false
 
 outputs:
   platforms:
@@ -23,3 +27,4 @@ outputs:
 runs:
   using: 'node20'
   main: 'dist/index.js'
+  post: 'dist/index.js'

src/context.ts

@@ -4,11 +4,13 @@ import {Util} from '@docker/actions-toolkit/lib/util';
 export interface Inputs {
   image: string;
   platforms: string;
+  cacheImage: boolean;
 }
 
 export function getInputs(): Inputs {
   return {
     image: core.getInput('image') || 'tonistiigi/binfmt:latest',
-    platforms: Util.getInputList('platforms').join(',') || 'all'
+    platforms: Util.getInputList('platforms').join(',') || 'all',
+    cacheImage: core.getBooleanInput('cache-image')
   };
 }

src/main.ts

@@ -20,7 +20,7 @@ actionsToolkit.run(
     });
 
     await core.group(`Pulling binfmt Docker image`, async () => {
-      await Exec.exec('docker', ['pull', input.image]);
+      await Docker.pull(input.image, input.cacheImage);
     });
 
     await core.group(`Image info`, async () => {