Add snapshot walk implementations

Temporarily remove zfs and aufs until interface update

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

metadata/adaptors.go

@@ -24,6 +24,7 @@ import (
 	"github.com/containerd/containerd/filters"
 	"github.com/containerd/containerd/images"
 	"github.com/containerd/containerd/leases"
+	"github.com/containerd/containerd/snapshots"
 )
 
 func adaptImage(o interface{}) filters.Adaptor {
@@ -139,6 +140,36 @@ func adaptLease(lease leases.Lease) filters.Adaptor {
 	})
 }
 
+func adaptSnapshot(info snapshots.Info) filters.Adaptor {
+	return filters.AdapterFunc(func(fieldpath []string) (string, bool) {
+		if len(fieldpath) == 0 {
+			return "", false
+		}
+
+		switch fieldpath[0] {
+		case "kind":
+			switch info.Kind {
+			case snapshots.KindActive:
+				return "active", true
+			case snapshots.KindView:
+				return "view", true
+			case snapshots.KindCommitted:
+				return "committed", true
+			}
+		case "name":
+			return info.Name, true
+		case "parent":
+			if info.Parent != "" {
+				return info.Parent, true
+			}
+		case "labels":
+			return checkMap(fieldpath[1:], info.Labels)
+		}
+
+		return "", false
+	})
+}
+
 func checkMap(fieldpath []string, m map[string]string) (string, bool) {
 	if len(m) == 0 {
 		return "", false

metadata/snapshot.go

@@ -25,6 +25,7 @@ import (
 	"time"
 
 	"github.com/containerd/containerd/errdefs"
+	"github.com/containerd/containerd/filters"
 	"github.com/containerd/containerd/labels"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/containerd/metadata/boltutil"
@@ -530,7 +531,7 @@ type infoPair struct {
 	info snapshots.Info
 }
 
-func (s *snapshotter) Walk(ctx context.Context, fn func(context.Context, snapshots.Info) error, filters ...string) error {
+func (s *snapshotter) Walk(ctx context.Context, fn snapshots.WalkFunc, fs ...string) error {
 	ns, err := namespaces.NamespaceRequired(ctx)
 	if err != nil {
 		return err
@@ -542,6 +543,11 @@ func (s *snapshotter) Walk(ctx context.Context, fn func(context.Context, snapsho
 		lastKey   string
 	)
 
+	filter, err := filters.ParseAll(fs...)
+	if err != nil {
+		return err
+	}
+
 	for {
 		if err := view(ctx, s.db, func(tx *bolt.Tx) error {
 			bkt := getSnapshotterBucket(tx, ns, s.name)
@@ -604,8 +610,11 @@ func (s *snapshotter) Walk(ctx context.Context, fn func(context.Context, snapsho
 				return err
 			}
 
-			if err := fn(ctx, overlayInfo(info, pair.info)); err != nil {
-				return err
+			info = overlayInfo(info, pair.info)
+			if filter.Match(adaptSnapshot(info)) {
+				if err := fn(ctx, info); err != nil {
+					return err
+				}
 			}
 		}