daemon/cluster/executor: Add volume `Subpath`

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

daemon/cluster/convert/container.go

@@ -120,8 +120,9 @@ func containerSpecFromGRPC(c *swarmapi.ContainerSpec) *types.ContainerSpec {
 
 		if m.VolumeOptions != nil {
 			mount.VolumeOptions = &mounttypes.VolumeOptions{
-				NoCopy: m.VolumeOptions.NoCopy,
-				Labels: m.VolumeOptions.Labels,
+				NoCopy:  m.VolumeOptions.NoCopy,
+				Labels:  m.VolumeOptions.Labels,
+				Subpath: m.VolumeOptions.Subpath,
 			}
 			if m.VolumeOptions.DriverConfig != nil {
 				mount.VolumeOptions.DriverConfig = &mounttypes.Driver{
@@ -406,8 +407,9 @@ func containerToGRPC(c *types.ContainerSpec) (*swarmapi.ContainerSpec, error) {
 
 		if m.VolumeOptions != nil {
 			mount.VolumeOptions = &swarmapi.Mount_VolumeOptions{
-				NoCopy: m.VolumeOptions.NoCopy,
-				Labels: m.VolumeOptions.Labels,
+				NoCopy:  m.VolumeOptions.NoCopy,
+				Labels:  m.VolumeOptions.Labels,
+				Subpath: m.VolumeOptions.Subpath,
 			}
 			if m.VolumeOptions.DriverConfig != nil {
 				mount.VolumeOptions.DriverConfig = &swarmapi.Driver{

daemon/cluster/convert/service_test.go

@@ -4,11 +4,13 @@ import (
 	"testing"
 
 	containertypes "github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/mount"
 	swarmtypes "github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/api/types/swarm/runtime"
 	google_protobuf3 "github.com/gogo/protobuf/types"
 	swarmapi "github.com/moby/swarmkit/v2/api"
 	"gotest.tools/v3/assert"
+	is "gotest.tools/v3/assert/cmp"
 )
 
 func TestServiceConvertFromGRPCRuntimeContainer(t *testing.T) {
@@ -611,3 +613,32 @@ func TestServiceConvertToGRPCConfigs(t *testing.T) {
 		})
 	}
 }
+
+func TestServiceConvertToGRPCVolumeSubpath(t *testing.T) {
+	s := swarmtypes.ServiceSpec{
+		TaskTemplate: swarmtypes.TaskSpec{
+			ContainerSpec: &swarmtypes.ContainerSpec{
+				Mounts: []mount.Mount{
+					{
+						Source:   "/foo/bar",
+						Target:   "/baz",
+						Type:     mount.TypeVolume,
+						ReadOnly: false,
+						VolumeOptions: &mount.VolumeOptions{
+							Subpath: "sub",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	g, err := ServiceSpecToGRPC(s)
+	assert.NilError(t, err)
+
+	v, ok := g.Task.Runtime.(*swarmapi.TaskSpec_Container)
+	assert.Assert(t, ok)
+
+	assert.Check(t, is.Len(v.Container.Mounts, 1))
+	assert.Check(t, is.Equal(v.Container.Mounts[0].VolumeOptions.Subpath, "sub"))
+}

daemon/cluster/executor/container/container.go

@@ -338,7 +338,8 @@ func convertMount(m api.Mount) enginemount.Mount {
 
 	if m.VolumeOptions != nil {
 		mount.VolumeOptions = &enginemount.VolumeOptions{
-			NoCopy: m.VolumeOptions.NoCopy,
+			NoCopy:  m.VolumeOptions.NoCopy,
+			Subpath: m.VolumeOptions.Subpath,
 		}
 		if m.VolumeOptions.Labels != nil {
 			mount.VolumeOptions.Labels = make(map[string]string, len(m.VolumeOptions.Labels))