cmd/dist: port commands over to use GRPC content store

Following from the rest of the work in this branch, we now are porting
the dist command to work directly against the containerd content API.

Signed-off-by: Stephen J Day <stephen.day@docker.com>

cmd/dist/get.go

@@ -4,6 +4,8 @@ import (
 	"io"
 	"os"
 
+	contentapi "github.com/docker/containerd/api/services/content"
+	"github.com/docker/containerd/content"
 	digest "github.com/opencontainers/go-digest"
 	"github.com/urfave/cli"
 )
@@ -17,17 +19,23 @@ var getCommand = cli.Command{
 Output paths can be used to directly access blobs on disk.`,
 	Flags: []cli.Flag{},
 	Action: func(context *cli.Context) error {
-		cs, err := resolveContentStore(context)
-		if err != nil {
-			return err
-		}
+		var (
+			ctx = background
+		)
 
 		dgst, err := digest.Parse(context.Args().First())
 		if err != nil {
 			return err
 		}
 
-		rc, err := cs.Open(dgst)
+		conn, err := connectGRPC(context)
+		if err != nil {
+			return err
+		}
+
+		cs := content.NewProviderFromClient(contentapi.NewContentClient(conn))
+
+		rc, err := cs.Reader(ctx, dgst)
 		if err != nil {
 			return err
 		}

cmd/dist/ingest.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 
+	contentapi "github.com/docker/containerd/api/services/content"
 	"github.com/docker/containerd/content"
 	"github.com/opencontainers/go-digest"
 	"github.com/urfave/cli"
@@ -41,7 +42,7 @@ var ingestCommand = cli.Command{
 			return err
 		}
 
-		cs, err := resolveContentStore(context)
+		conn, err := connectGRPC(context)
 		if err != nil {
 			return err
 		}
@@ -50,9 +51,11 @@ var ingestCommand = cli.Command{
 			return fmt.Errorf("must specify a transaction reference")
 		}
 
+		ingester := content.NewIngesterFromClient(contentapi.NewContentClient(conn))
+
 		// TODO(stevvooe): Allow ingest to be reentrant. Currently, we expect
 		// all data to be written in a single invocation. Allow multiple writes
 		// to the same transaction key followed by a commit.
-		return content.WriteBlob(ctx, cs, os.Stdin, ref, expectedSize, expectedDigest)
+		return content.WriteBlob(ctx, ingester, os.Stdin, ref, expectedSize, expectedDigest)
 	},
 }

cmd/dist/main.go

@@ -42,6 +42,11 @@ distribution tool
 			Usage: "path to content store root",
 			Value: "/tmp/content", // TODO(stevvooe): for now, just use the PWD/.content
 		},
+		cli.StringFlag{
+			Name:  "socket, s",
+			Usage: "socket path for containerd's GRPC server",
+			Value: "/run/containerd/containerd.sock",
+		},
 	}
 	app.Commands = []cli.Command{
 		fetchCommand,