allow skipping saving the layers

Author: btkostner

action.yml

@@ -11,13 +11,17 @@ inputs:
     required: true
     default: docker-layer-caching-${{ github.workflow }}-{hash}
   restore-keys:
-    description: An ordered list of keys to use for restoring the cache if no cache hit occurred for key 
+    description: An ordered list of keys to use for restoring the cache if no cache hit occurred for key
     required: false
     default: docker-layer-caching-${{ github.workflow }}-
   concurrency:
     description: The number of concurrency when restoring and saving layers
     required: true
     default: '4'
+  skip-save:
+    description: Skip saving layers in the post step
+    required: false
+    default: false
 
 runs:
   using: node12

post.ts

@@ -5,6 +5,11 @@ import { LayerCache } from './src/LayerCache'
 import { ImageDetector } from './src/ImageDetector'
 import { assertType } from 'typescript-is'
 const main = async () => {
+  if (core.getInput('skip-save')) {
+    core.info('Skipping save.')
+    return
+  }
+
   const primaryKey = core.getInput('key', { required: true })
   const restoredKey = JSON.parse(core.getState(`restored-key`)) as string