Merge pull request #1150 from dmcgowan/content-labels

Content labels

api/services/content/v1/content.proto

@@ -3,6 +3,7 @@ syntax = "proto3";
 package containerd.services.content.v1;
 
 import "gogoproto/gogo.proto";
+import "google/protobuf/field_mask.proto";
 import "google/protobuf/timestamp.proto";
 import "google/protobuf/empty.proto";
 
@@ -16,6 +17,13 @@ service Content {
 	// existence.
 	rpc Info(InfoRequest) returns (InfoResponse);
 
+	// Update updates content metadata.
+	//
+	// This call can be used to manage the mutable content labels. The
+	// immutable metadata such as digest, size, and committed at cannot
+	// be updated.
+	rpc Update(UpdateRequest) returns (UpdateResponse);
+
 	// List streams the entire set of content as Info objects and closes the
 	// stream.
 	//
@@ -75,6 +83,12 @@ message Info {
 
 	// CommittedAt provides the time at which the blob was committed.
 	google.protobuf.Timestamp committed_at = 3 [(gogoproto.stdtime) = true, (gogoproto.nullable) = false];
+
+	// UpdatedAt provides the time the info was last updated.
+	google.protobuf.Timestamp updated_at = 4 [(gogoproto.stdtime) = true, (gogoproto.nullable) = false];
+
+	// Labels are arbitrary data on content.
+	map<string, string> labels  = 5;
 }
 
 message InfoRequest {
@@ -85,7 +99,35 @@ message InfoResponse {
 	Info info = 1 [(gogoproto.nullable) = false];
 }
 
-message ListContentRequest {}
+message UpdateRequest {
+	Info info = 1 [(gogoproto.nullable) = false];
+
+	// UpdateMask specifies which fields to perform the update on. If empty,
+	// the operation applies to all fields.
+	//
+	// In info, Digest, Size, and CommittedAt are immutable,
+	// other field may be updated using this mask.
+	// If no mask is provided, all mutable field are updated.
+	google.protobuf.FieldMask update_mask = 2;
+}
+
+message UpdateResponse {
+	Info info = 1 [(gogoproto.nullable) = false];
+}
+
+message ListContentRequest {
+	// Filters contains one or more filters using the syntax defined in the
+	// containerd filter package.
+	//
+	// The returned result will be those that match any of the provided
+	// filters. Expanded, containers that match the following will be
+	// returned:
+	//
+	//   filters[0] or filters[1] or ... or filters[n-1] or filters[n]
+	//
+	// If filters is zero-length or nil, all items will be returned.
+	repeated string filters = 1;
+}
 
 message ListContentResponse {
 	repeated Info info = 1 [(gogoproto.nullable) = false];

cmd/dist/labels.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/containerd/containerd/content"
+	digest "github.com/opencontainers/go-digest"
+	"github.com/urfave/cli"
+)
+
+var labelCommand = cli.Command{
+	Name:        "label",
+	Usage:       "adds labels to content",
+	ArgsUsage:   "[flags] <digest> [<label>=<value> ...]",
+	Description: `Labels blobs in the content store`,
+	Flags:       []cli.Flag{},
+	Action: func(context *cli.Context) error {
+		var (
+			object, labels = objectWithLabelArgs(context)
+		)
+		ctx, cancel := appContext(context)
+		defer cancel()
+
+		cs, err := resolveContentStore(context)
+		if err != nil {
+			return err
+		}
+
+		dgst, err := digest.Parse(object)
+		if err != nil {
+			return err
+		}
+
+		info := content.Info{
+			Digest: dgst,
+			Labels: map[string]string{},
+		}
+
+		var paths []string
+		for k, v := range labels {
+			paths = append(paths, fmt.Sprintf("labels.%s", k))
+			if v != "" {
+				info.Labels[k] = v
+			}
+		}
+
+		// Nothing updated, do no clear
+		if len(paths) == 0 {
+			info, err = cs.Info(ctx, info.Digest)
+		} else {
+			info, err = cs.Update(ctx, info, paths...)
+		}
+		if err != nil {
+			return err
+		}
+
+		var labelStrings []string
+		for k, v := range info.Labels {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%s", k, v))
+		}
+
+		fmt.Println(strings.Join(labelStrings, ","))
+
+		return nil
+	},
+}

cmd/dist/list.go

@@ -3,11 +3,11 @@ package main
 import (
 	"fmt"
 	"os"
+	"strings"
 	"text/tabwriter"
 	"time"
 
 	"github.com/containerd/containerd/content"
-	"github.com/containerd/containerd/log"
 	units "github.com/docker/go-units"
 	"github.com/urfave/cli"
 )
@@ -16,7 +16,7 @@ var listCommand = cli.Command{
 	Name:        "list",
 	Aliases:     []string{"ls"},
 	Usage:       "list all blobs in the store.",
-	ArgsUsage:   "[flags] [<prefix>, ...]",
+	ArgsUsage:   "[flags] [<filter>, ...]",
 	Description: `List blobs in the content store.`,
 	Flags: []cli.Flag{
 		cli.BoolFlag{
@@ -37,12 +37,6 @@ var listCommand = cli.Command{
 			return err
 		}
 
-		if len(args) > 0 {
-			// TODO(stevvooe): Implement selection of a few blobs. Not sure
-			// what kind of efficiency gains we can actually get here.
-			log.G(ctx).Warnf("args ignored; need to implement matchers")
-		}
-
 		var walkFn content.WalkFunc
 		if quiet {
 			walkFn = func(info content.Info) error {
@@ -53,17 +47,27 @@ var listCommand = cli.Command{
 			tw := tabwriter.NewWriter(os.Stdout, 1, 8, 1, '\t', 0)
 			defer tw.Flush()
 
-			fmt.Fprintln(tw, "DIGEST\tSIZE\tAGE")
+			fmt.Fprintln(tw, "DIGEST\tSIZE\tAGE\tLABELS")
 			walkFn = func(info content.Info) error {
-				fmt.Fprintf(tw, "%s\t%s\t%s\n",
+				var labelStrings []string
+				for k, v := range info.Labels {
+					labelStrings = append(labelStrings, strings.Join([]string{k, v}, "="))
+				}
+				labels := strings.Join(labelStrings, ",")
+				if labels == "" {
+					labels = "-"
+				}
+
+				fmt.Fprintf(tw, "%s\t%s\t%s\t%s\n",
 					info.Digest,
 					units.HumanSize(float64(info.Size)),
-					units.HumanDuration(time.Since(info.CommittedAt)))
+					units.HumanDuration(time.Since(info.CommittedAt)),
+					labels)
 				return nil
 			}
 
 		}
 
-		return cs.Walk(ctx, walkFn)
+		return cs.Walk(ctx, walkFn, args...)
 	},
 }

cmd/dist/main.go

@@ -101,5 +101,6 @@ var contentCommand = cli.Command{
 		getCommand,
 		editCommand,
 		deleteCommand,
+		labelCommand,
 	},
 }

content/content.go

@@ -32,6 +32,8 @@ type Info struct {
 	Digest      digest.Digest
 	Size        int64
 	CommittedAt time.Time
+	UpdatedAt   time.Time
+	Labels      map[string]string
 }
 
 type Status struct {
@@ -53,8 +55,17 @@ type Manager interface {
 	// If the content is not present, ErrNotFound will be returned.
 	Info(ctx context.Context, dgst digest.Digest) (Info, error)
 
-	// Walk will call fn for each item in the content store.
+	// Update updates mutable information related to content.
-	Walk(ctx context.Context, fn WalkFunc) error
+	// If one or more fieldpaths are provided, only those
+	// fields will be updated.
+	// Mutable fields:
+	//  labels.*
+	Update(ctx context.Context, info Info, fieldpaths ...string) (Info, error)
+
+	// Walk will call fn for each item in the content store which
+	// match the provided filters. If no filters are given all
+	// items will be walked.
+	Walk(ctx context.Context, fn WalkFunc, filters ...string) error
 
 	// Delete removes the content from the store.
 	Delete(ctx context.Context, dgst digest.Digest) error

content/store.go

@@ -55,6 +55,7 @@ func (s *store) info(dgst digest.Digest, fi os.FileInfo) Info {
 		Digest:      dgst,
 		Size:        fi.Size(),
 		CommittedAt: fi.ModTime(),
+		UpdatedAt:   fi.ModTime(),
 	}
 }
 
@@ -92,9 +93,13 @@ func (cs *store) Delete(ctx context.Context, dgst digest.Digest) error {
 	return nil
 }
 
-// TODO(stevvooe): Allow querying the set of blobs in the blob store.
+func (cs *store) Update(ctx context.Context, info Info, fieldpaths ...string) (Info, error) {
+	// TODO: Support persisting and updating mutable content data
+	return Info{}, errors.Wrapf(errdefs.ErrFailedPrecondition, "update not supported on immutable content store")
+}
 
-func (cs *store) Walk(ctx context.Context, fn WalkFunc) error {
+func (cs *store) Walk(ctx context.Context, fn WalkFunc, filters ...string) error {
+	// TODO: Support filters
 	root := filepath.Join(cs.root, "blobs")
 	var alg digest.Algorithm
 	return filepath.Walk(root, func(path string, fi os.FileInfo, err error) error {

image.go

@@ -7,6 +7,7 @@ import (
 	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/images"
 	"github.com/containerd/containerd/rootfs"
+	digest "github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 )
@@ -39,14 +40,44 @@ func (i *image) Unpack(ctx context.Context, snapshotterName string) error {
 	if err != nil {
 		return err
 	}
-	if _, err := rootfs.ApplyLayers(ctx, layers, i.client.SnapshotService(snapshotterName), i.client.DiffService()); err != nil {
+
+	sn := i.client.SnapshotService(snapshotterName)
+	a := i.client.DiffService()
+	cs := i.client.ContentStore()
+
+	var chain []digest.Digest
+	for _, layer := range layers {
+		unpacked, err := rootfs.ApplyLayer(ctx, layer, chain, sn, a)
+		if err != nil {
+			// TODO: possibly wait and retry if extraction of same chain id was in progress
 			return err
 		}
+		if unpacked {
+			info, err := cs.Info(ctx, layer.Blob.Digest)
+			if err != nil {
+				return err
+			}
+			if info.Labels["containerd.io/uncompressed"] != layer.Diff.Digest.String() {
+				if info.Labels == nil {
+					info.Labels = map[string]string{}
+				}
+				info.Labels["containerd.io/uncompressed"] = layer.Diff.Digest.String()
+				if _, err := cs.Update(ctx, info, "labels.containerd.io/uncompressed"); err != nil {
+					return err
+				}
+			}
+		}
+
+		chain = append(chain, layer.Diff.Digest)
+	}
+
 	return nil
 }
 
 func (i *image) getLayers(ctx context.Context) ([]rootfs.Layer, error) {
 	cs := i.client.ContentStore()
+
+	// TODO: Support manifest list
 	p, err := content.ReadBlob(ctx, cs, i.i.Target.Digest)
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to read manifest blob")

metadata/adaptors.go

@@ -70,6 +70,25 @@ func adaptContainer(o interface{}) filters.Adaptor {
 	})
 }
 
+func adaptContentInfo(info content.Info) filters.Adaptor {
+	return filters.AdapterFunc(func(fieldpath []string) (string, bool) {
+		if len(fieldpath) == 0 {
+			return "", false
+		}
+
+		switch fieldpath[0] {
+		case "digest":
+			return info.Digest.String(), true
+		case "size":
+			// TODO: support size based filtering
+		case "labels":
+			return checkMap(fieldpath[1:], info.Labels)
+		}
+
+		return "", false
+	})
+}
+
 func adaptContentStatus(status content.Status) filters.Adaptor {
 	return filters.AdapterFunc(func(fieldpath []string) (string, bool) {
 		if len(fieldpath) == 0 {

metadata/content.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"encoding/binary"
 	"io"
+	"strings"
+	"time"
 
 	"github.com/boltdb/bolt"
 	"github.com/containerd/containerd/content"
@@ -50,8 +52,64 @@ func (cs *contentStore) Info(ctx context.Context, dgst digest.Digest) (content.I
 	return info, nil
 }
 
-func (cs *contentStore) Walk(ctx context.Context, fn content.WalkFunc) error {
+func (cs *contentStore) Update(ctx context.Context, info content.Info, fieldpaths ...string) (content.Info, error) {
 	ns, err := namespaces.NamespaceRequired(ctx)
+	if err != nil {
+		return content.Info{}, err
+	}
+
+	updated := content.Info{
+		Digest: info.Digest,
+	}
+	if err := update(ctx, cs.db, func(tx *bolt.Tx) error {
+		bkt := getBlobBucket(tx, ns, info.Digest)
+		if bkt == nil {
+			return errors.Wrapf(errdefs.ErrNotFound, "content digest %v", info.Digest)
+		}
+
+		if err := readInfo(&updated, bkt); err != nil {
+			return errors.Wrapf(err, "info %q", info.Digest)
+		}
+
+		if len(fieldpaths) > 0 {
+			for _, path := range fieldpaths {
+				if strings.HasPrefix(path, "labels.") {
+					if updated.Labels == nil {
+						updated.Labels = map[string]string{}
+					}
+
+					key := strings.TrimPrefix(path, "labels.")
+					updated.Labels[key] = info.Labels[key]
+					continue
+				}
+
+				switch path {
+				case "labels":
+					updated.Labels = info.Labels
+				default:
+					return errors.Wrapf(errdefs.ErrInvalidArgument, "cannot update %q field on content info %q", path, info.Digest)
+				}
+			}
+		} else {
+			// Set mutable fields
+			updated.Labels = info.Labels
+		}
+
+		updated.UpdatedAt = time.Now().UTC()
+		return writeInfo(&updated, bkt)
+	}); err != nil {
+		return content.Info{}, err
+	}
+	return updated, nil
+}
+
+func (cs *contentStore) Walk(ctx context.Context, fn content.WalkFunc, fs ...string) error {
+	ns, err := namespaces.NamespaceRequired(ctx)
+	if err != nil {
+		return err
+	}
+
+	filter, err := filters.ParseAll(fs...)
 	if err != nil {
 		return err
 	}
@@ -67,6 +125,11 @@ func (cs *contentStore) Walk(ctx context.Context, fn content.WalkFunc) error {
 		return bkt.ForEach(func(k, v []byte) error {
 			dgst, err := digest.Parse(string(k))
 			if err != nil {
+				// Not a digest, skip
+				return nil
+			}
+			bbkt := bkt.Bucket(k)
+			if bbkt == nil {
 				return nil
 			}
 			info := content.Info{
@@ -75,7 +138,9 @@ func (cs *contentStore) Walk(ctx context.Context, fn content.WalkFunc) error {
 			if err := readInfo(&info, bkt.Bucket(k)); err != nil {
 				return err
 			}
+			if filter.Match(adaptContentInfo(info)) {
 				infos = append(infos, info)
+			}
 			return nil
 		})
 	}); err != nil {
@@ -367,16 +432,43 @@ func (cs *contentStore) checkAccess(ctx context.Context, dgst digest.Digest) err
 }
 
 func readInfo(info *content.Info, bkt *bolt.Bucket) error {
-	return bkt.ForEach(func(k, v []byte) error {
+	if err := readTimestamps(&info.CommittedAt, &info.UpdatedAt, bkt); err != nil {
-		switch string(k) {
-		case string(bucketKeyCreatedAt):
-			if err := info.CommittedAt.UnmarshalBinary(v); err != nil {
 		return err
 	}
-		case string(bucketKeySize):
+
+	lbkt := bkt.Bucket(bucketKeyLabels)
+	if lbkt != nil {
+		info.Labels = map[string]string{}
+		if err := readLabels(info.Labels, lbkt); err != nil {
+			return err
+		}
+	}
+
+	if v := bkt.Get(bucketKeySize); len(v) > 0 {
 		info.Size, _ = binary.Varint(v)
 	}
-		// TODO: Read labels
+
+	return nil
+}
+
+func writeInfo(info *content.Info, bkt *bolt.Bucket) error {
+	if err := writeTimestamps(bkt, info.CommittedAt, info.UpdatedAt); err != nil {
+		return err
+	}
+
+	if err := writeLabels(bkt, info.Labels); err != nil {
+		return errors.Wrapf(err, "writing labels for info %v", info.Digest)
+	}
+
+	// Write size
+	sizeEncoded, err := encodeSize(info.Size)
+	if err != nil {
+		return err
+	}
+
+	if err := bkt.Put(bucketKeySize, sizeEncoded); err != nil {
+		return err
+	}
+
 	return nil
-	})
 }

metadata/helpers.go

@@ -27,6 +27,10 @@ func writeLabels(bkt *bolt.Bucket, labels map[string]string) error {
 		}
 	}
 
+	if len(labels) == 0 {
+		return nil
+	}
+
 	lbkt, err := bkt.CreateBucket(bucketKeyLabels)
 	if err != nil {
 		return err

metadata/images.go

@@ -232,11 +232,9 @@ func writeImage(bkt *bolt.Bucket, image *images.Image) error {
 		return err
 	}
 
-	if len(image.Labels) > 0 {
 	if err := writeLabels(bkt, image.Labels); err != nil {
 		return errors.Wrapf(err, "writing labels for image %v", image.Name)
 	}
-	}
 
 	// write the target bucket
 	tbkt, err := bkt.CreateBucketIfNotExists([]byte(bucketKeyTarget))

rootfs/apply.go

@@ -14,19 +14,28 @@ import (
 	"golang.org/x/net/context"
 )
 
+// Applier is used to apply a descriptor of a layer diff on top of mounts.
 type Applier interface {
 	Apply(context.Context, ocispec.Descriptor, []mount.Mount) (ocispec.Descriptor, error)
 }
 
+// Layer represents the descriptors for a layer diff. These descriptions
+// include the descriptor for the uncompressed tar diff as well as a blob
+// used to transport that tar. The blob descriptor may or may not describe
+// a compressed object.
 type Layer struct {
 	Diff ocispec.Descriptor
 	Blob ocispec.Descriptor
 }
 
+// ApplyLayers applies all the layers using the given snapshotter and applier.
+// The returned result is a chain id digest representing all the applied layers.
+// Layers are applied in order they are given, making the first layer the
+// bottom-most layer in the layer chain.
 func ApplyLayers(ctx context.Context, layers []Layer, sn snapshot.Snapshotter, a Applier) (digest.Digest, error) {
 	var chain []digest.Digest
 	for _, layer := range layers {
-		if err := applyLayer(ctx, layer, chain, sn, a); err != nil {
+		if _, err := ApplyLayer(ctx, layer, chain, sn, a); err != nil {
 			// TODO: possibly wait and retry if extraction of same chain id was in progress
 			return "", err
 		}
@@ -36,7 +45,10 @@ func ApplyLayers(ctx context.Context, layers []Layer, sn snapshot.Snapshotter, a
 	return identity.ChainID(chain), nil
 }
 
-func applyLayer(ctx context.Context, layer Layer, chain []digest.Digest, sn snapshot.Snapshotter, a Applier) error {
+// ApplyLayer applies a single layer on top of the given provided layer chain,
+// using the provided snapshotter and applier. If the layer was unpacked true
+// is returned, if the layer already exists false is returned.
+func ApplyLayer(ctx context.Context, layer Layer, chain []digest.Digest, sn snapshot.Snapshotter, a Applier) (bool, error) {
 	var (
 		parent  = identity.ChainID(chain)
 		chainID = identity.ChainID(append(chain, layer.Diff.Digest))
@@ -46,9 +58,9 @@ func applyLayer(ctx context.Context, layer Layer, chain []digest.Digest, sn snap
 	_, err := sn.Stat(ctx, chainID.String())
 	if err == nil {
 		log.G(ctx).Debugf("Extraction not needed, layer snapshot exists")
-		return nil
+		return false, nil
 	} else if !errdefs.IsNotFound(err) {
-		return errors.Wrap(err, "failed to stat snapshot")
+		return false, errors.Wrap(err, "failed to stat snapshot")
 	}
 
 	key := fmt.Sprintf("extract %s", chainID)
@@ -57,7 +69,7 @@ func applyLayer(ctx context.Context, layer Layer, chain []digest.Digest, sn snap
 	mounts, err := sn.Prepare(ctx, key, parent.String())
 	if err != nil {
 		//TODO: If is snapshot exists error, retry
-		return errors.Wrap(err, "failed to prepare extraction layer")
+		return false, errors.Wrap(err, "failed to prepare extraction layer")
 	}
 	defer func() {
 		if err != nil {
@@ -70,16 +82,16 @@ func applyLayer(ctx context.Context, layer Layer, chain []digest.Digest, sn snap
 
 	diff, err = a.Apply(ctx, layer.Blob, mounts)
 	if err != nil {
-		return errors.Wrapf(err, "failed to extract layer %s", layer.Diff.Digest)
+		return false, errors.Wrapf(err, "failed to extract layer %s", layer.Diff.Digest)
 	}
 	if diff.Digest != layer.Diff.Digest {
 		err = errors.Errorf("wrong diff id calculated on extraction %q", diff.Digest)
-		return err
+		return false, err
 	}
 
 	if err = sn.Commit(ctx, chainID.String(), key); err != nil {
-		return errors.Wrapf(err, "failed to commit snapshot %s", parent)
+		return false, errors.Wrapf(err, "failed to commit snapshot %s", parent)
 	}
 
-	return nil
+	return true, nil
 }

rootfs/diff.go

@@ -3,23 +3,24 @@ package rootfs
 import (
 	"fmt"
 
-	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/mount"
 	"github.com/containerd/containerd/snapshot"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"golang.org/x/net/context"
 )
 
+// MountDiffer computes the difference between two mounts and returns a
+// descriptor for the computed diff. The provided ref can be used to track
+// the content creation of the diff and media type is used to determine the
+// format of the created content.
 type MountDiffer interface {
 	DiffMounts(ctx context.Context, lower, upper []mount.Mount, media, ref string) (ocispec.Descriptor, error)
 }
 
-type DiffOptions struct {
+// Diff creates a layer diff for the given snapshot identifier from the parent
-	MountDiffer
+// of the snapshot. A content ref is provided to track the progress of the
-	content.Store
+// content creation and the provided snapshotter and mount differ are used
-	snapshot.Snapshotter
+// for calculating the diff. The descriptor for the layer diff is returned.
-}
-
 func Diff(ctx context.Context, snapshotID, contentRef string, sn snapshot.Snapshotter, md MountDiffer) (ocispec.Descriptor, error) {
 	info, err := sn.Stat(ctx, snapshotID)
 	if err != nil {

services/content/service.go

@@ -79,11 +79,22 @@ func (s *Service) Info(ctx context.Context, req *api.InfoRequest) (*api.InfoResp
 	}
 
 	return &api.InfoResponse{
-		Info: api.Info{
+		Info: infoToGRPC(bi),
-			Digest:      bi.Digest,
+	}, nil
-			Size_:       bi.Size,
+}
-			CommittedAt: bi.CommittedAt,
+
-		},
+func (s *Service) Update(ctx context.Context, req *api.UpdateRequest) (*api.UpdateResponse, error) {
+	if err := req.Info.Digest.Validate(); err != nil {
+		return nil, grpc.Errorf(codes.InvalidArgument, "%q failed validation", req.Info.Digest)
+	}
+
+	info, err := s.store.Update(ctx, infoFromGRPC(req.Info), req.UpdateMask.GetPaths()...)
+	if err != nil {
+		return nil, errdefs.ToGRPC(err)
+	}
+
+	return &api.UpdateResponse{
+		Info: infoToGRPC(info),
 	}, nil
 }
 
@@ -103,6 +114,7 @@ func (s *Service) List(req *api.ListContentRequest, session api.Content_ListServ
 			Digest:      info.Digest,
 			Size_:       info.Size,
 			CommittedAt: info.CommittedAt,
+			Labels:      info.Labels,
 		})
 
 		if len(buffer) >= 100 {
@@ -114,7 +126,7 @@ func (s *Service) List(req *api.ListContentRequest, session api.Content_ListServ
 		}
 
 		return nil
-	}); err != nil {
+	}, req.Filters...); err != nil {
 		return err
 	}
 

services/content/store.go

@@ -7,6 +7,7 @@ import (
 	contentapi "github.com/containerd/containerd/api/services/content/v1"
 	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/errdefs"
+	protobuftypes "github.com/gogo/protobuf/types"
 	digest "github.com/opencontainers/go-digest"
 )
 
@@ -28,15 +29,13 @@ func (rs *remoteStore) Info(ctx context.Context, dgst digest.Digest) (content.In
 		return content.Info{}, errdefs.FromGRPC(err)
 	}
 
-	return content.Info{
+	return infoFromGRPC(resp.Info), nil
-		Digest:      resp.Info.Digest,
-		Size:        resp.Info.Size_,
-		CommittedAt: resp.Info.CommittedAt,
-	}, nil
 }
 
-func (rs *remoteStore) Walk(ctx context.Context, fn content.WalkFunc) error {
+func (rs *remoteStore) Walk(ctx context.Context, fn content.WalkFunc, filters ...string) error {
-	session, err := rs.client.List(ctx, &contentapi.ListContentRequest{})
+	session, err := rs.client.List(ctx, &contentapi.ListContentRequest{
+		Filters: filters,
+	})
 	if err != nil {
 		return errdefs.FromGRPC(err)
 	}
@@ -52,11 +51,7 @@ func (rs *remoteStore) Walk(ctx context.Context, fn content.WalkFunc) error {
 		}
 
 		for _, info := range msg.Info {
-			if err := fn(content.Info{
+			if err := fn(infoFromGRPC(info)); err != nil {
-				Digest:      info.Digest,
-				Size:        info.Size_,
-				CommittedAt: info.CommittedAt,
-			}); err != nil {
 				return err
 			}
 		}
@@ -113,6 +108,19 @@ func (rs *remoteStore) Status(ctx context.Context, ref string) (content.Status,
 	}, nil
 }
 
+func (rs *remoteStore) Update(ctx context.Context, info content.Info, fieldpaths ...string) (content.Info, error) {
+	resp, err := rs.client.Update(ctx, &contentapi.UpdateRequest{
+		Info: infoToGRPC(info),
+		UpdateMask: &protobuftypes.FieldMask{
+			Paths: fieldpaths,
+		},
+	})
+	if err != nil {
+		return content.Info{}, errdefs.FromGRPC(err)
+	}
+	return infoFromGRPC(resp.Info), nil
+}
+
 func (rs *remoteStore) ListStatuses(ctx context.Context, filters ...string) ([]content.Status, error) {
 	resp, err := rs.client.ListStatuses(ctx, &contentapi.ListStatusesRequest{
 		Filters: filters,
@@ -182,3 +190,23 @@ func (rs *remoteStore) negotiate(ctx context.Context, ref string, size int64, ex
 
 	return wrclient, resp.Offset, nil
 }
+
+func infoToGRPC(info content.Info) contentapi.Info {
+	return contentapi.Info{
+		Digest:      info.Digest,
+		Size_:       info.Size,
+		CommittedAt: info.CommittedAt,
+		UpdatedAt:   info.UpdatedAt,
+		Labels:      info.Labels,
+	}
+}
+
+func infoFromGRPC(info contentapi.Info) content.Info {
+	return content.Info{
+		Digest:      info.Digest,
+		Size:        info.Size_,
+		CommittedAt: info.CommittedAt,
+		UpdatedAt:   info.UpdatedAt,
+		Labels:      info.Labels,
+	}
+}