@@ -1859,6 +1859,13 @@ definitions:

                 type: "string"

                 x-nullable: false

                 example: "plugins.sock"

+              ProtocolScheme:

+                type: "string"

+                example: "some.protocol/v1.0"

+                description: "Protocol to use for clients connecting to the plugin."

+                enum:

+                  - ""

+                  - "moby.plugins.http/v1"

           Entrypoint:

             type: "array"

             items:

@@ -121,6 +121,9 @@ type PluginConfigArgs struct {

 // swagger:model PluginConfigInterface

 type PluginConfigInterface struct {

+	// Protocol to use for clients connecting to the plugin.

+	ProtocolScheme string `json:"ProtocolScheme,omitempty"`

+

 	// socket

 	// Required: true

 	Socket string `json:"Socket"`

@@ -5,7 +5,9 @@ import (

 	"path/filepath"

 	"github.com/docker/docker/pkg/plugingetter"

+	"github.com/docker/docker/pkg/plugins"

 	"github.com/docker/docker/plugin/v2"

+	"github.com/pkg/errors"

 )

 func lookupPlugin(name string, pg plugingetter.PluginGetter, config Options) (Driver, error) {

@@ -28,6 +30,22 @@ func newPluginDriver(name string, pl plugingetter.CompatPlugin, config Options)

 			}

 		}

 	}

-	proxy := &graphDriverProxy{name, pl, Capabilities{}}

+

+	var proxy *graphDriverProxy

+

+	pa, ok := pl.(plugingetter.PluginAddr)

+	if !ok {

+		proxy = &graphDriverProxy{name, pl, Capabilities{}, pl.Client()}

+	} else {

+		if pa.Protocol() != plugins.ProtocolSchemeHTTPV1 {

+			return nil, errors.Errorf("plugin protocol not supported: %s", pa.Protocol())

+		}

+		addr := pa.Addr()

+		client, err := plugins.NewClientWithTimeout(addr.Network()+"://"+addr.String(), nil, pa.Timeout())

+		if err != nil {

+			return nil, errors.Wrap(err, "error creating plugin client")

+		}

+		proxy = &graphDriverProxy{name, pl, Capabilities{}, client}

+	}

 	return proxy, proxy.Init(filepath.Join(home, name), config.DriverOptions, config.UIDMaps, config.GIDMaps)

 }

@@ -13,9 +13,10 @@ import (

 )

 type graphDriverProxy struct {

-	name string

-	p    plugingetter.CompatPlugin

-	caps Capabilities

+	name   string

+	p      plugingetter.CompatPlugin

+	caps   Capabilities

+	client *plugins.Client

 }

 type graphDriverRequest struct {

@@ -57,7 +58,7 @@ func (d *graphDriverProxy) Init(home string, opts []string, uidMaps, gidMaps []i

 		GIDMaps: gidMaps,

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Init", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Init", args, &ret); err != nil {

 		return err

 	}

 	if ret.Err != "" {

@@ -74,7 +75,7 @@ func (d *graphDriverProxy) Init(home string, opts []string, uidMaps, gidMaps []i

 func (d *graphDriverProxy) fetchCaps() (Capabilities, error) {

 	args := &graphDriverRequest{}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Capabilities", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Capabilities", args, &ret); err != nil {

 		if !plugins.IsNotFound(err) {

 			return Capabilities{}, err

 		}

@@ -108,7 +109,7 @@ func (d *graphDriverProxy) create(method, id, parent string, opts *CreateOpts) e

 		args.StorageOpt = opts.StorageOpt

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call(method, args, &ret); err != nil {

+	if err := d.client.Call(method, args, &ret); err != nil {

 		return err

 	}

 	if ret.Err != "" {

@@ -120,7 +121,7 @@ func (d *graphDriverProxy) create(method, id, parent string, opts *CreateOpts) e

 func (d *graphDriverProxy) Remove(id string) error {

 	args := &graphDriverRequest{ID: id}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Remove", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Remove", args, &ret); err != nil {

 		return err

 	}

 	if ret.Err != "" {

@@ -135,7 +136,7 @@ func (d *graphDriverProxy) Get(id, mountLabel string) (containerfs.ContainerFS,

 		MountLabel: mountLabel,

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Get", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Get", args, &ret); err != nil {

 		return nil, err

 	}

 	var err error

@@ -148,7 +149,7 @@ func (d *graphDriverProxy) Get(id, mountLabel string) (containerfs.ContainerFS,

 func (d *graphDriverProxy) Put(id string) error {

 	args := &graphDriverRequest{ID: id}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Put", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Put", args, &ret); err != nil {

 		return err

 	}

 	if ret.Err != "" {

@@ -160,7 +161,7 @@ func (d *graphDriverProxy) Put(id string) error {

 func (d *graphDriverProxy) Exists(id string) bool {

 	args := &graphDriverRequest{ID: id}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Exists", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Exists", args, &ret); err != nil {

 		return false

 	}

 	return ret.Exists

@@ -169,7 +170,7 @@ func (d *graphDriverProxy) Exists(id string) bool {

 func (d *graphDriverProxy) Status() [][2]string {

 	args := &graphDriverRequest{}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Status", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Status", args, &ret); err != nil {

 		return nil

 	}

 	return ret.Status

@@ -180,7 +181,7 @@ func (d *graphDriverProxy) GetMetadata(id string) (map[string]string, error) {

 		ID: id,

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.GetMetadata", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.GetMetadata", args, &ret); err != nil {

 		return nil, err

 	}

 	if ret.Err != "" {

@@ -199,7 +200,7 @@ func (d *graphDriverProxy) Cleanup() error {

 	args := &graphDriverRequest{}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Cleanup", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Cleanup", args, &ret); err != nil {

 		return nil

 	}

 	if ret.Err != "" {

@@ -213,7 +214,7 @@ func (d *graphDriverProxy) Diff(id, parent string) (io.ReadCloser, error) {

 		ID:     id,

 		Parent: parent,

 	}

-	body, err := d.p.Client().Stream("GraphDriver.Diff", args)

+	body, err := d.client.Stream("GraphDriver.Diff", args)

 	if err != nil {

 		return nil, err

 	}

@@ -226,7 +227,7 @@ func (d *graphDriverProxy) Changes(id, parent string) ([]archive.Change, error)

 		Parent: parent,

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.Changes", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.Changes", args, &ret); err != nil {

 		return nil, err

 	}

 	if ret.Err != "" {

@@ -238,7 +239,7 @@ func (d *graphDriverProxy) Changes(id, parent string) ([]archive.Change, error)

 func (d *graphDriverProxy) ApplyDiff(id, parent string, diff io.Reader) (int64, error) {

 	var ret graphDriverResponse

-	if err := d.p.Client().SendFile(fmt.Sprintf("GraphDriver.ApplyDiff?id=%s&parent=%s", id, parent), diff, &ret); err != nil {

+	if err := d.client.SendFile(fmt.Sprintf("GraphDriver.ApplyDiff?id=%s&parent=%s", id, parent), diff, &ret); err != nil {

 		return -1, err

 	}

 	if ret.Err != "" {

@@ -253,7 +254,7 @@ func (d *graphDriverProxy) DiffSize(id, parent string) (int64, error) {

 		Parent: parent,

 	}

 	var ret graphDriverResponse

-	if err := d.p.Client().Call("GraphDriver.DiffSize", args, &ret); err != nil {

+	if err := d.client.Call("GraphDriver.DiffSize", args, &ret); err != nil {

 		return -1, err

 	}

 	if ret.Err != "" {

@@ -8,6 +8,7 @@ import (

 	"github.com/docker/docker/api/types/plugins/logdriver"

 	getter "github.com/docker/docker/pkg/plugingetter"

+	"github.com/docker/docker/pkg/plugins"

 	"github.com/docker/docker/pkg/stringid"

 	"github.com/pkg/errors"

 )

@@ -37,11 +38,32 @@ func getPlugin(name string, mode int) (Creator, error) {

 		return nil, fmt.Errorf("error looking up logging plugin %s: %v", name, err)

 	}

-	d := &logPluginProxy{p.Client()}

-	return makePluginCreator(name, d, p.ScopedPath), nil

+	client, err := makePluginClient(p)

+	if err != nil {

+		return nil, err

+	}

+	return makePluginCreator(name, client, p.ScopedPath), nil

+}

+

+func makePluginClient(p getter.CompatPlugin) (logPlugin, error) {

+	pa, ok := p.(getter.PluginAddr)

+	if !ok {

+		return &logPluginProxy{p.Client()}, nil

+	}

+

+	if pa.Protocol() != plugins.ProtocolSchemeHTTPV1 {

+		return nil, errors.Errorf("plugin protocol not supported: %s", p)

+	}

+

+	addr := pa.Addr()

+	c, err := plugins.NewClientWithTimeout(addr.Network()+"://"+addr.String(), nil, pa.Timeout())

+	if err != nil {

+		return nil, errors.Wrap(err, "error making plugin client")

+	}

+	return &logPluginProxy{c}, nil

 }

-func makePluginCreator(name string, l *logPluginProxy, scopePath func(s string) string) Creator {

+func makePluginCreator(name string, l logPlugin, scopePath func(s string) string) Creator {

 	return func(logCtx Info) (logger Logger, err error) {

 		defer func() {

 			if err != nil {

@@ -4,6 +4,7 @@ import (

 	"sync"

 	"github.com/docker/docker/pkg/plugingetter"

+	"github.com/docker/docker/pkg/plugins"

 	"github.com/docker/go-metrics"

 	"github.com/pkg/errors"

 	"github.com/prometheus/client_golang/prometheus"

@@ -118,7 +119,15 @@ func (d *Daemon) cleanupMetricsPlugins() {

 		p := plugin

 		go func() {

 			defer wg.Done()

-			pluginStopMetricsCollection(p)

+

+			adapter, err := makePluginAdapter(p)

+			if err != nil {

+				logrus.WithError(err).WithField("plugin", p.Name()).Error("Error creating metrics plugin adapater")

+				return

+			}

+			if err := adapter.StopMetrics(); err != nil {

+				logrus.WithError(err).WithField("plugin", p.Name()).Error("Error stopping plugin metrics collection")

+			}

 		}()

 	}

 	wg.Wait()

@@ -128,12 +137,39 @@ func (d *Daemon) cleanupMetricsPlugins() {

 	}

 }

-func pluginStartMetricsCollection(p plugingetter.CompatPlugin) error {

+type metricsPlugin interface {

+	StartMetrics() error

+	StopMetrics() error

+}

+

+func makePluginAdapter(p plugingetter.CompatPlugin) (metricsPlugin, error) {

+	pa, ok := p.(plugingetter.PluginAddr)

+	if !ok {

+		return &metricsPluginAdapter{p.Client(), p.Name()}, nil

+	}

+	if pa.Protocol() != plugins.ProtocolSchemeHTTPV1 {

+		return nil, errors.Errorf("plugin protocol not supported: %s", pa.Protocol())

+	}

+

+	addr := pa.Addr()

+	client, err := plugins.NewClientWithTimeout(addr.Network()+"://"+addr.String(), nil, pa.Timeout())

+	if err != nil {

+		return nil, errors.Wrap(err, "error creating metrics plugin client")

+	}

+	return &metricsPluginAdapter{client, p.Name()}, nil

+}

+

+type metricsPluginAdapter struct {

+	c    *plugins.Client

+	name string

+}

+

+func (a *metricsPluginAdapter) StartMetrics() error {

 	type metricsPluginResponse struct {

 		Err string

 	}

 	var res metricsPluginResponse

-	if err := p.Client().Call(metricsPluginType+".StartMetrics", nil, &res); err != nil {

+	if err := a.c.Call(metricsPluginType+".StartMetrics", nil, &res); err != nil {

 		return errors.Wrap(err, "could not start metrics plugin")

 	}

 	if res.Err != "" {

@@ -142,8 +178,9 @@ func pluginStartMetricsCollection(p plugingetter.CompatPlugin) error {

 	return nil

 }

-func pluginStopMetricsCollection(p plugingetter.CompatPlugin) {

-	if err := p.Client().Call(metricsPluginType+".StopMetrics", nil, nil); err != nil {

-		logrus.WithError(err).WithField("name", p.Name()).Error("error stopping metrics collector")

+func (a *metricsPluginAdapter) StopMetrics() error {

+	if err := a.c.Call(metricsPluginType+".StopMetrics", nil, nil); err != nil {

+		return errors.Wrap(err, "error stopping metrics collector")

 	}

+	return nil

 }

@@ -49,8 +49,12 @@ func registerMetricsPluginCallback(store *plugin.Store, sockPath string) {

 			return

 		}

-		if err := pluginStartMetricsCollection(p); err != nil {

-			logrus.WithError(err).WithField("name", name).Error("error while initializing metrics plugin")

+		adapter, err := makePluginAdapter(p)

+		if err != nil {

+			logrus.WithError(err).WithField("plugin", p.Name()).Error("Error creating plugin adapater")

+		}

+		if err := adapter.StartMetrics(); err != nil {

+			logrus.WithError(err).WithField("plugin", p.Name()).Error("Error starting metrics collector plugin")

 		}

 	})

 }

@@ -1,6 +1,9 @@

 package plugingetter // import "github.com/docker/docker/pkg/plugingetter"

 import (

+	"net"

+	"time"

+

 	"github.com/docker/docker/pkg/plugins"

 )

@@ -21,6 +24,14 @@ type CompatPlugin interface {

 	IsV1() bool

 }

+// PluginAddr is a plugin that exposes the socket address for creating custom clients rather than the built-in `*plugins.Client`

+type PluginAddr interface {

+	CompatPlugin

+	Addr() net.Addr

+	Timeout() time.Duration

+	Protocol() string

+}

+

 // CountedPlugin is a plugin which is reference counted.

 type CountedPlugin interface {

 	Acquire()

@@ -31,6 +31,9 @@ import (

 	"github.com/sirupsen/logrus"

 )

+// ProtocolSchemeHTTPV1 is the name of the protocol used for interacting with plugins using this package.

+const ProtocolSchemeHTTPV1 = "moby.plugins.http/v1"

+

 var (

 	// ErrNotImplements is returned if the plugin does not implement the requested driver.

 	ErrNotImplements = errors.New("Plugin does not implement the requested driver")

@@ -88,6 +91,11 @@ func (p *Plugin) Client() *Client {

 	return p.client

 }

+// Protocol returns the protocol name/version used for plugins in this package.

+func (p *Plugin) Protocol() string {

+	return ProtocolSchemeHTTPV1

+}

+

 // IsV1 returns true for V1 plugins and false otherwise.

 func (p *Plugin) IsV1() bool {

 	return true

@@ -71,14 +71,20 @@ func (pm *Manager) enable(p *v2.Plugin, c *controller, force bool) error {

 func (pm *Manager) pluginPostStart(p *v2.Plugin, c *controller) error {

 	sockAddr := filepath.Join(pm.config.ExecRoot, p.GetID(), p.GetSocket())

-	client, err := plugins.NewClientWithTimeout("unix://"+sockAddr, nil, time.Duration(c.timeoutInSecs)*time.Second)

-	if err != nil {

-		c.restart = false

-		shutdownPlugin(p, c, pm.executor)

-		return errors.WithStack(err)

-	}

+	p.SetTimeout(time.Duration(c.timeoutInSecs) * time.Second)

+	addr := &net.UnixAddr{Net: "unix", Name: sockAddr}

+	p.SetAddr(addr)

-	p.SetPClient(client)

+	if p.Protocol() == plugins.ProtocolSchemeHTTPV1 {

+		client, err := plugins.NewClientWithTimeout(addr.Network()+"://"+addr.String(), nil, p.Timeout())

+		if err != nil {

+			c.restart = false

+			shutdownPlugin(p, c, pm.executor)

+			return errors.WithStack(err)

+		}

+

+		p.SetPClient(client)

+	}

 	// Initial sleep before net Dial to allow plugin to listen on socket.

 	time.Sleep(500 * time.Millisecond)

@@ -2,9 +2,11 @@ package v2 // import "github.com/docker/docker/plugin/v2"

 import (

 	"fmt"

+	"net"

 	"path/filepath"

 	"strings"

 	"sync"

+	"time"

 	"github.com/docker/docker/api/types"

 	"github.com/docker/docker/pkg/plugingetter"

@@ -27,6 +29,8 @@ type Plugin struct {

 	modifyRuntimeSpec func(*specs.Spec)

 	SwarmServiceID string

+	timeout        time.Duration

+	addr           net.Addr

 }

 const defaultPluginRuntimeDestination = "/run/docker/plugins"

@@ -50,6 +54,7 @@ func (p *Plugin) ScopedPath(s string) string {

 }

 // Client returns the plugin client.

+// Deprecated: use p.Addr() and manually create the client

 func (p *Plugin) Client() *plugins.Client {

 	p.mu.RLock()

 	defer p.mu.RUnlock()

@@ -58,6 +63,7 @@ func (p *Plugin) Client() *plugins.Client {

 }

 // SetPClient set the plugin client.

+// Deprecated: Hardcoded plugin client is deprecated

 func (p *Plugin) SetPClient(client *plugins.Client) {

 	p.mu.Lock()

 	defer p.mu.Unlock()

@@ -264,3 +270,42 @@ func (p *Plugin) SetSpecOptModifier(f func(*specs.Spec)) {

 	p.modifyRuntimeSpec = f

 	p.mu.Unlock()

 }

+

+// Timeout gets the currently configured connection timeout.

+// This should be used when dialing the plugin.

+func (p *Plugin) Timeout() time.Duration {

+	p.mu.RLock()

+	t := p.timeout

+	p.mu.RUnlock()

+	return t

+}

+

+// SetTimeout sets the timeout to use for dialing.

+func (p *Plugin) SetTimeout(t time.Duration) {

+	p.mu.Lock()

+	p.timeout = t

+	p.mu.Unlock()

+}

+

+// Addr returns the net.Addr to use to connect to the plugin socket

+func (p *Plugin) Addr() net.Addr {

+	p.mu.RLock()

+	addr := p.addr

+	p.mu.RUnlock()

+	return addr

+}

+

+// SetAddr sets the plugin address which can be used for dialing the plugin.

+func (p *Plugin) SetAddr(addr net.Addr) {

+	p.mu.Lock()

+	p.addr = addr

+	p.mu.Unlock()

+}

+

+// Protocol is the protocol that should be used for interacting with the plugin.

+func (p *Plugin) Protocol() string {

+	if p.PluginObj.Config.Interface.ProtocolScheme != "" {

+		return p.PluginObj.Config.Interface.ProtocolScheme

+	}

+	return plugins.ProtocolSchemeHTTPV1

+}

@@ -5,7 +5,7 @@ package v2 // import "github.com/docker/docker/plugin/v2"

 import (

 	"errors"

-	specs "github.com/opencontainers/runtime-spec/specs-go"

+	"github.com/opencontainers/runtime-spec/specs-go"

 )

 // InitSpec creates an OCI spec from the plugin's config.

@@ -17,7 +17,7 @@ type volumeDriverAdapter struct {

 	name         string

 	scopePath    func(s string) string

 	capabilities *volume.Capability

-	proxy        *volumeDriverProxy

+	proxy        volumeDriver

 }

 func (a *volumeDriverAdapter) Name() string {

@@ -114,7 +114,7 @@ func (a *volumeDriverAdapter) getCapabilities() volume.Capability {

 }

 type volumeAdapter struct {

-	proxy      *volumeDriverProxy

+	proxy      volumeDriver

 	name       string

 	scopePath  func(string) string

 	driverName string

@@ -10,6 +10,7 @@ import (

 	"github.com/docker/docker/errdefs"

 	"github.com/docker/docker/pkg/locker"

 	getter "github.com/docker/docker/pkg/plugingetter"

+	"github.com/docker/docker/pkg/plugins"

 	"github.com/docker/docker/volume"

 	"github.com/pkg/errors"

 	"github.com/sirupsen/logrus"

@@ -17,12 +18,6 @@ import (

 const extName = "VolumeDriver"

-// NewVolumeDriver returns a driver has the given name mapped on the given client.

-func NewVolumeDriver(name string, scopePath func(string) string, c client) volume.Driver {

-	proxy := &volumeDriverProxy{c}

-	return &volumeDriverAdapter{name: name, scopePath: scopePath, proxy: proxy}

-}

-

 // volumeDriver defines the available functions that volume plugins must implement.

 // This interface is only defined to generate the proxy objects.

 // It's not intended to be public or reused.

@@ -93,7 +88,10 @@ func (s *Store) lookup(name string, mode int) (volume.Driver, error) {

 			return nil, errors.Wrap(err, "error looking up volume plugin "+name)

 		}

-		d := NewVolumeDriver(p.Name(), p.ScopedPath, p.Client())

+		d, err := makePluginAdapter(p)

+		if err != nil {

+			return nil, errors.Wrap(err, "error making plugin client")

+		}

 		if err := validateDriver(d); err != nil {

 			if mode > 0 {

 				// Undo any reference count changes from the initial `Get`

@@ -201,7 +199,10 @@ func (s *Store) GetAllDrivers() ([]volume.Driver, error) {

 			continue

 		}

-		ext := NewVolumeDriver(name, p.ScopedPath, p.Client())

+		ext, err := makePluginAdapter(p)

+		if err != nil {

+			return nil, errors.Wrap(err, "error making plugin client")

+		}

 		if p.IsV1() {

 			s.extensions[name] = ext

 		}

@@ -209,3 +210,22 @@ func (s *Store) GetAllDrivers() ([]volume.Driver, error) {

 	}

 	return ds, nil

 }

+

+func makePluginAdapter(p getter.CompatPlugin) (*volumeDriverAdapter, error) {

+	pa, ok := p.(getter.PluginAddr)

+	if !ok {

+		return &volumeDriverAdapter{name: p.Name(), scopePath: p.ScopedPath, proxy: &volumeDriverProxy{p.Client()}}, nil

+	}

+

+	if pa.Protocol() != plugins.ProtocolSchemeHTTPV1 {

+		return nil, errors.Errorf("plugin protocol not supported: %s", p)

+	}

+

+	addr := pa.Addr()

+	client, err := plugins.NewClientWithTimeout(addr.Network()+"://"+addr.String(), nil, pa.Timeout())

+	if err != nil {

+		return nil, errors.Wrap(err, "error creating plugin client")

+	}

+

+	return &volumeDriverAdapter{name: p.Name(), scopePath: p.ScopedPath, proxy: &volumeDriverProxy{client}}, nil

+}