LCOW: Fix ImageCache to address right store

Signed-off-by: John Howard <jhoward@microsoft.com>

builder/builder.go

@@ -78,7 +78,7 @@ type Result struct {
 // ImageCacheBuilder represents a generator for stateful image cache.
 type ImageCacheBuilder interface {
 	// MakeImageCache creates a stateful image cache.
-	MakeImageCache(cacheFrom []string) ImageCache
+	MakeImageCache(cacheFrom []string, platform string) ImageCache
 }
 
 // ImageCache abstracts an image cache.

builder/dockerfile/builder.go

@@ -166,7 +166,7 @@ func newBuilder(clientCtx context.Context, options builderOptions) *Builder {
 		buildStages:      newBuildStages(),
 		imageSources:     newImageSources(clientCtx, options),
 		pathCache:        options.PathCache,
-		imageProber:      newImageProber(options.Backend, config.CacheFrom, config.NoCache),
+		imageProber:      newImageProber(options.Backend, config.CacheFrom, options.Platform, config.NoCache),
 		containerManager: newContainerManager(options.Backend),
 		platform:         options.Platform,
 	}

builder/dockerfile/dispatchers_test.go

@@ -63,7 +63,7 @@ func newBuilderWithMockBackend() *Builder {
 			Backend: mockBackend,
 		}),
 		buildStages:      newBuildStages(),
-		imageProber:      newImageProber(mockBackend, nil, false),
+		imageProber:      newImageProber(mockBackend, nil, runtime.GOOS, false),
 		containerManager: newContainerManager(mockBackend),
 	}
 	return b
@@ -488,10 +488,10 @@ func TestRunWithBuildArgs(t *testing.T) {
 	}
 
 	mockBackend := b.docker.(*MockBackend)
-	mockBackend.makeImageCacheFunc = func(_ []string) builder.ImageCache {
+	mockBackend.makeImageCacheFunc = func(_ []string, _ string) builder.ImageCache {
 		return imageCache
 	}
-	b.imageProber = newImageProber(mockBackend, nil, false)
+	b.imageProber = newImageProber(mockBackend, nil, runtime.GOOS, false)
 	mockBackend.getImageFunc = func(_ string) (builder.Image, builder.ReleaseableLayer, error) {
 		return &mockImage{
 			id:     "abcdef",

builder/dockerfile/imageprobe.go

@@ -19,13 +19,13 @@ type imageProber struct {
 	cacheBusted bool
 }
 
-func newImageProber(cacheBuilder builder.ImageCacheBuilder, cacheFrom []string, noCache bool) ImageProber {
+func newImageProber(cacheBuilder builder.ImageCacheBuilder, cacheFrom []string, platform string, noCache bool) ImageProber {
 	if noCache {
 		return &nopProber{}
 	}
 
 	reset := func() builder.ImageCache {
-		return cacheBuilder.MakeImageCache(cacheFrom)
+		return cacheBuilder.MakeImageCache(cacheFrom, platform)
 	}
 	return &imageProber{cache: reset(), reset: reset}
 }

builder/dockerfile/mockbackend_test.go

@@ -18,7 +18,7 @@ type MockBackend struct {
 	containerCreateFunc func(config types.ContainerCreateConfig) (container.ContainerCreateCreatedBody, error)
 	commitFunc          func(string, *backend.ContainerCommitConfig) (string, error)
 	getImageFunc        func(string) (builder.Image, builder.ReleaseableLayer, error)
-	makeImageCacheFunc  func(cacheFrom []string) builder.ImageCache
+	makeImageCacheFunc  func(cacheFrom []string, platform string) builder.ImageCache
 }
 
 func (m *MockBackend) ContainerAttachRaw(cID string, stdin io.ReadCloser, stdout, stderr io.Writer, stream bool, attached chan struct{}) error {
@@ -71,9 +71,9 @@ func (m *MockBackend) GetImageAndReleasableLayer(ctx context.Context, refOrID st
 	return &mockImage{id: "theid"}, &mockLayer{}, nil
 }
 
-func (m *MockBackend) MakeImageCache(cacheFrom []string) builder.ImageCache {
+func (m *MockBackend) MakeImageCache(cacheFrom []string, platform string) builder.ImageCache {
 	if m.makeImageCacheFunc != nil {
-		return m.makeImageCacheFunc(cacheFrom)
+		return m.makeImageCacheFunc(cacheFrom, platform)
 	}
 	return nil
 }

daemon/cache.go

@@ -1,22 +1,18 @@
 package daemon
 
 import (
-	"runtime"
-
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/builder"
 	"github.com/docker/docker/image/cache"
 )
 
 // MakeImageCache creates a stateful image cache.
-func (daemon *Daemon) MakeImageCache(sourceRefs []string) builder.ImageCache {
+func (daemon *Daemon) MakeImageCache(sourceRefs []string, platform string) builder.ImageCache {
 	if len(sourceRefs) == 0 {
-		// TODO @jhowardmsft LCOW. For now, assume it is the OS of the host
-		return cache.NewLocal(daemon.stores[runtime.GOOS].imageStore)
+		return cache.NewLocal(daemon.stores[platform].imageStore)
 	}
 
-	// TODO @jhowardmsft LCOW. For now, assume it is the OS of the host
-	cache := cache.New(daemon.stores[runtime.GOOS].imageStore)
+	cache := cache.New(daemon.stores[platform].imageStore)
 
 	for _, ref := range sourceRefs {
 		img, err := daemon.GetImage(ref)