add optional fields in daemon.json to enable buildkit

Signed-off-by: Anda Xu <anda.xu@docker.com>
Upstream-commit: 2be17666b4cf21995da3e4ddf4ed615e6e6ca63a
Component: engine

components/engine/cmd/dockerd/config.go

@@ -65,7 +65,6 @@ func installCommonConfigFlags(conf *config.Config, flags *pflag.FlagSet) {
 
 	flags.StringVar(&conf.SwarmDefaultAdvertiseAddr, "swarm-default-advertise-addr", "", "Set default address or interface for swarm advertised address")
 	flags.BoolVar(&conf.Experimental, "experimental", false, "Enable experimental features")
-
 	flags.StringVar(&conf.MetricsAddress, "metrics-addr", "", "Set default address and port to serve the metrics api on")
 
 	flags.Var(opts.NewNamedListOptsRef("node-generic-resources", &conf.NodeGenericResources, opts.ValidateSingleGenericResource), "node-generic-resource", "Advertise user-defined resource")

components/engine/cmd/dockerd/daemon.go

@@ -27,6 +27,7 @@ import (
 	swarmrouter "github.com/docker/docker/api/server/router/swarm"
 	systemrouter "github.com/docker/docker/api/server/router/system"
 	"github.com/docker/docker/api/server/router/volume"
+	"github.com/docker/docker/api/types"
 	buildkit "github.com/docker/docker/builder/builder-next"
 	"github.com/docker/docker/builder/dockerfile"
 	"github.com/docker/docker/builder/fscache"
@@ -253,6 +254,7 @@ type routerOptions struct {
 	buildBackend   *buildbackend.Backend
 	buildCache     *fscache.FSCache // legacy
 	buildkit       *buildkit.Builder
+	builderVersion types.BuilderVersion
 	daemon         *daemon.Daemon
 	api            *apiserver.Server
 	cluster        *cluster.Cluster
@@ -283,8 +285,7 @@ func newRouterOptions(config *config.Config, daemon *daemon.Daemon) (routerOptio
 	if err != nil {
 		return opts, err
 	}
-
-	buildkit, err := buildkit.New(buildkit.Opt{
+	bk, err := buildkit.New(buildkit.Opt{
 		SessionManager: sm,
 		Root:           filepath.Join(config.Root, "buildkit"),
 		Dist:           daemon.DistributionServices(),
@@ -293,16 +294,24 @@ func newRouterOptions(config *config.Config, daemon *daemon.Daemon) (routerOptio
 		return opts, err
 	}
 
-	bb, err := buildbackend.NewBackend(daemon.ImageService(), manager, buildCache, buildkit)
+	bb, err := buildbackend.NewBackend(daemon.ImageService(), manager, buildCache, bk)
 	if err != nil {
 		return opts, errors.Wrap(err, "failed to create buildmanager")
 	}
-
+	var bv types.BuilderVersion
+	if v, ok := config.Features["buildkit"]; ok {
+		if v {
+			bv = types.BuilderBuildKit
+		} else {
+			bv = types.BuilderV1
+		}
+	}
 	return routerOptions{
 		sessionManager: sm,
 		buildBackend:   bb,
 		buildCache:     buildCache,
-		buildkit:       buildkit,
+		buildkit:       bk,
+		builderVersion: bv,
 		daemon:         daemon,
 	}, nil
 }
@@ -476,9 +485,9 @@ func initRouter(opts routerOptions) {
 		checkpointrouter.NewRouter(opts.daemon, decoder),
 		container.NewRouter(opts.daemon, decoder),
 		image.NewRouter(opts.daemon.ImageService()),
-		systemrouter.NewRouter(opts.daemon, opts.cluster, opts.buildCache, opts.buildkit),
+		systemrouter.NewRouter(opts.daemon, opts.cluster, opts.buildCache, opts.buildkit, opts.builderVersion),
 		volume.NewRouter(opts.daemon.VolumesService()),
-		build.NewRouter(opts.buildBackend, opts.daemon),
+		build.NewRouter(opts.buildBackend, opts.daemon, opts.builderVersion),
 		sessionrouter.NewRouter(opts.sessionManager),
 		swarmrouter.NewRouter(opts.cluster),
 		pluginrouter.NewRouter(opts.daemon.PluginManager()),