Merge pull request #2117 from dmcgowan/update-fetch-handlers

content: support manifest labeling on completed content ingests on the client

images/handlers.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/containerd/containerd/content"
+	"github.com/containerd/containerd/platforms"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 	"golang.org/x/sync/errgroup"
@@ -128,8 +129,78 @@ func Dispatch(ctx context.Context, handler Handler, descs ...ocispec.Descriptor)
 //
 // One can also replace this with another implementation to allow descending of
 // arbitrary types.
-func ChildrenHandler(provider content.Provider, platform string) HandlerFunc {
+func ChildrenHandler(provider content.Provider) HandlerFunc {
 	return func(ctx context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
-		return Children(ctx, provider, desc, platform)
+		return Children(ctx, provider, desc)
+	}
+}
+
+// SetChildrenLabels is a handler wrapper which sets labels for the content on
+// the children returned by the handler and passes through the children.
+// Must follow a handler that returns the children to be labeled.
+func SetChildrenLabels(manager content.Manager, f HandlerFunc) HandlerFunc {
+	return func(ctx context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
+		children, err := f(ctx, desc)
+		if err != nil {
+			return children, err
+		}
+
+		if len(children) > 0 {
+			info := content.Info{
+				Digest: desc.Digest,
+				Labels: map[string]string{},
+			}
+			fields := []string{}
+			for i, ch := range children {
+				info.Labels[fmt.Sprintf("containerd.io/gc.ref.content.%d", i)] = ch.Digest.String()
+				fields = append(fields, fmt.Sprintf("labels.containerd.io/gc.ref.content.%d", i))
+			}
+
+			_, err := manager.Update(ctx, info, fields...)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		return children, err
+	}
+}
+
+// FilterPlatform is a handler wrapper which limits the descriptors returned
+// by a handler to a single platform.
+func FilterPlatform(platform string, f HandlerFunc) HandlerFunc {
+	return func(ctx context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
+		children, err := f(ctx, desc)
+		if err != nil {
+			return children, err
+		}
+
+		var descs []ocispec.Descriptor
+		if platform != "" && isMultiPlatform(desc.MediaType) {
+			matcher, err := platforms.Parse(platform)
+			if err != nil {
+				return nil, err
+			}
+
+			for _, d := range children {
+				if d.Platform == nil || matcher.Match(*d.Platform) {
+					descs = append(descs, d)
+				}
+			}
+		} else {
+			descs = children
+		}
+
+		return descs, nil
+	}
+
+}
+
+func isMultiPlatform(mediaType string) bool {
+	switch mediaType {
+	case MediaTypeDockerSchema2ManifestList, ocispec.MediaTypeImageIndex:
+		return true
+	default:
+		return false
 	}
 }

images/image.go

@@ -102,7 +102,7 @@ func (image *Image) Size(ctx context.Context, provider content.Provider, platfor
 		}
 		size += desc.Size
 		return nil, nil
-	}), ChildrenHandler(provider, platform)), image.Target)
+	}), FilterPlatform(platform, ChildrenHandler(provider))), image.Target)
 }
 
 // Manifest resolves a manifest from the image for the given platform.
@@ -238,7 +238,7 @@ func Platforms(ctx context.Context, provider content.Provider, image ocispec.Des
 				platforms.Normalize(ocispec.Platform{OS: image.OS, Architecture: image.Architecture}))
 		}
 		return nil, nil
-	}), ChildrenHandler(provider, "")), image)
+	}), ChildrenHandler(provider)), image)
 }
 
 // Check returns nil if the all components of an image are available in the
@@ -285,7 +285,7 @@ func Check(ctx context.Context, provider content.Provider, image ocispec.Descrip
 }
 
 // Children returns the immediate children of content described by the descriptor.
-func Children(ctx context.Context, provider content.Provider, desc ocispec.Descriptor, platform string) ([]ocispec.Descriptor, error) {
+func Children(ctx context.Context, provider content.Provider, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
 	var descs []ocispec.Descriptor
 	switch desc.MediaType {
 	case MediaTypeDockerSchema2Manifest, ocispec.MediaTypeImageManifest:
@@ -314,21 +314,7 @@ func Children(ctx context.Context, provider content.Provider, desc ocispec.Descr
 			return nil, err
 		}
 
-		if platform != "" {
-			matcher, err := platforms.Parse(platform)
-			if err != nil {
-				return nil, err
-			}
-
-			for _, d := range index.Manifests {
-				if d.Platform == nil || matcher.Match(*d.Platform) {
-					descs = append(descs, d)
-				}
-			}
-		} else {
-			descs = append(descs, index.Manifests...)
-		}
-
+		descs = append(descs, index.Manifests...)
 	case MediaTypeDockerSchema2Layer, MediaTypeDockerSchema2LayerGzip,
 		MediaTypeDockerSchema2LayerForeign, MediaTypeDockerSchema2LayerForeignGzip,
 		MediaTypeDockerSchema2Config, ocispec.MediaTypeImageConfig,

images/oci/exporter.go

@@ -42,7 +42,7 @@ func (oe *V1Exporter) Export(ctx context.Context, store content.Provider, desc o
 	}
 
 	handlers := images.Handlers(
-		images.ChildrenHandler(store, platforms.Default()),
+		images.FilterPlatform(platforms.Default(), images.ChildrenHandler(store)),
 		images.HandlerFunc(exportHandler),
 	)