Merge pull request #107 from noxiouz/layers_order

isolate(porto): merge layers according to a manifest Scheme

Author: noxiouz

isolate/porto/box.go

@@ -28,8 +28,8 @@ import (
 	porto "github.com/yandex/porto/src/api/go"
 	portorpc "github.com/yandex/porto/src/api/go/rpc"
 
-	_ "github.com/docker/distribution/manifest/schema1"
-	_ "github.com/docker/distribution/manifest/schema2"
+	"github.com/docker/distribution/manifest/schema1"
+	"github.com/docker/distribution/manifest/schema2"
 	"github.com/docker/distribution/reference"
 	"github.com/docker/distribution/registry/client"
 	"github.com/docker/distribution/registry/client/transport"
@@ -405,8 +405,17 @@ func (b *Box) Spool(ctx context.Context, name string, opts isolate.Profile) (err
 		return err
 	}
 	apexctx.GetLogger(ctx).WithField("name", name).Infof("create a layer %s in Porto with merge", layerName)
+	var order layersOrder
+	switch manifest.(type) {
+	case schema1.SignedManifest, *schema1.SignedManifest:
+		order = layerOrderV1
+	case schema2.DeserializedManifest, *schema2.DeserializedManifest:
+		order = layerOrderV2
+	default:
+		return fmt.Errorf("unknown manifest type %T", manifest)
+	}
 
-	for _, descriptor := range manifest.References() {
+	for _, descriptor := range order(manifest.References()) {
 		blobPath, err := b.blobRepo.Get(ctx, repo, descriptor.Digest)
 		if err != nil {
 			return err

isolate/porto/utils.go

@@ -7,6 +7,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/docker/distribution"
 	porto "github.com/yandex/porto/src/api/go"
 	portorpc "github.com/yandex/porto/src/api/go/rpc"
 )
@@ -144,3 +145,19 @@ func portoConnect() (porto.API, error) {
 		return nil, err
 	}
 }
+
+type layersOrder func(references []distribution.Descriptor) []distribution.Descriptor
+
+var layerOrderV1 layersOrder = func(references []distribution.Descriptor) []distribution.Descriptor {
+	return func(slice []distribution.Descriptor) []distribution.Descriptor {
+		size := len(slice) - 1
+		for i := 0; i < len(slice)/2; i++ {
+			slice[i], slice[size-i] = slice[size-i], slice[i]
+		}
+		return slice
+	}(references)
+}
+
+var layerOrderV2 layersOrder = func(references []distribution.Descriptor) []distribution.Descriptor {
+	return references
+}