@@ -76,7 +76,7 @@ func (b *Backend) Build(ctx context.Context, config backend.BuildConfig) (string

 		return "", nil

 	}

-	var imageID = build.ImageID

+	imageID := build.ImageID

 	if options.Squash {

 		if imageID, err = squashBuild(build, b.imageComponent); err != nil {

 			return "", err

@@ -15,7 +15,6 @@ type Backend interface {

 	// Prune build cache

 	PruneCache(context.Context, types.BuildCachePruneOptions) (*types.BuildCachePruneReport, error)

-

 	Cancel(context.Context, string) error

 }

@@ -107,7 +107,7 @@ func newImageBuildOptions(ctx context.Context, r *http.Request) (*types.ImageBui

 	}

 	if ulimitsJSON := r.FormValue("ulimits"); ulimitsJSON != "" {

-		var buildUlimits = []*units.Ulimit{}

+		buildUlimits := []*units.Ulimit{}

 		if err := json.Unmarshal([]byte(ulimitsJSON), &buildUlimits); err != nil {

 			return nil, invalidParam{errors.Wrap(err, "error reading ulimit settings")}

 		}

@@ -127,7 +127,7 @@ func newImageBuildOptions(ctx context.Context, r *http.Request) (*types.ImageBui

 	// so that it can print a warning about "foo" being unused if there is

 	// no "ARG foo" in the Dockerfile.

 	if buildArgsJSON := r.FormValue("buildargs"); buildArgsJSON != "" {

-		var buildArgs = map[string]*string{}

+		buildArgs := map[string]*string{}

 		if err := json.Unmarshal([]byte(buildArgsJSON), &buildArgs); err != nil {

 			return nil, invalidParam{errors.Wrap(err, "error reading build args")}

 		}

@@ -135,7 +135,7 @@ func newImageBuildOptions(ctx context.Context, r *http.Request) (*types.ImageBui

 	}

 	if labelsJSON := r.FormValue("labels"); labelsJSON != "" {

-		var labels = map[string]string{}

+		labels := map[string]string{}

 		if err := json.Unmarshal([]byte(labelsJSON), &labels); err != nil {

 			return nil, invalidParam{errors.Wrap(err, "error reading labels")}

 		}

@@ -143,7 +143,7 @@ func newImageBuildOptions(ctx context.Context, r *http.Request) (*types.ImageBui

 	}

 	if cacheFromJSON := r.FormValue("cachefrom"); cacheFromJSON != "" {

-		var cacheFrom = []string{}

+		cacheFrom := []string{}

 		if err := json.Unmarshal([]byte(cacheFromJSON), &cacheFrom); err != nil {

 			return nil, invalidParam{errors.Wrap(err, "error reading cache-from")}

 		}

@@ -35,7 +35,6 @@ func (s *checkpointRouter) getContainerCheckpoints(ctx context.Context, w http.R

 	checkpoints, err := s.backend.CheckpointList(vars["name"], types.CheckpointListOptions{

 		CheckpointDir: r.Form.Get("dir"),

 	})

-

 	if err != nil {

 		return err

 	}

@@ -52,7 +51,6 @@ func (s *checkpointRouter) deleteContainerCheckpoint(ctx context.Context, w http

 		CheckpointDir: r.Form.Get("dir"),

 		CheckpointID:  vars["checkpoint"],

 	})

-

 	if err != nil {

 		return err

 	}

@@ -53,7 +53,6 @@ type monitorBackend interface {

 	ContainerLogs(ctx context.Context, name string, config *types.ContainerLogsOptions) (msgs <-chan *backend.LogMessage, tty bool, err error)

 	ContainerStats(ctx context.Context, name string, config *backend.ContainerStatsConfig) error

 	ContainerTop(name string, psArgs string) (*container.ContainerTopOKBody, error)

-

 	Containers(ctx context.Context, config *types.ContainerListOptions) ([]*types.Container, error)

 }

@@ -449,7 +449,7 @@ func (ir *imageRouter) getImagesSearch(ctx context.Context, w http.ResponseWrite

 	// AuthConfig to increase compatibility with the existing API.

 	authConfig, _ := registry.DecodeAuthConfig(r.Header.Get(registry.AuthHeader))

-	var headers = http.Header{}

+	headers := http.Header{}

 	for k, v := range r.Header {

 		k = http.CanonicalHeaderKey(k)

 		if strings.HasPrefix(k, "X-Meta-") {

@@ -186,7 +186,8 @@ func (pr *pluginRouter) createPlugin(ctx context.Context, w http.ResponseWriter,

 	}

 	options := &types.PluginCreateOptions{

-		RepoName: r.FormValue("name")}

+		RepoName: r.FormValue("name"),

+	}

 	if err := pr.backend.CreateFromContext(ctx, r.Body, options); err != nil {

 		return err

@@ -17,29 +17,23 @@ type Backend interface {

 	Update(uint64, types.Spec, types.UpdateFlags) error

 	GetUnlockKey() (string, error)

 	UnlockSwarm(req types.UnlockRequest) error

-

 	GetServices(basictypes.ServiceListOptions) ([]types.Service, error)

 	GetService(idOrName string, insertDefaults bool) (types.Service, error)

 	CreateService(types.ServiceSpec, string, bool) (*basictypes.ServiceCreateResponse, error)

 	UpdateService(string, uint64, types.ServiceSpec, basictypes.ServiceUpdateOptions, bool) (*basictypes.ServiceUpdateResponse, error)

 	RemoveService(string) error

-

 	ServiceLogs(context.Context, *backend.LogSelector, *basictypes.ContainerLogsOptions) (<-chan *backend.LogMessage, error)

-

 	GetNodes(basictypes.NodeListOptions) ([]types.Node, error)

 	GetNode(string) (types.Node, error)

 	UpdateNode(string, uint64, types.NodeSpec) error

 	RemoveNode(string, bool) error

-

 	GetTasks(basictypes.TaskListOptions) ([]types.Task, error)

 	GetTask(string) (types.Task, error)

-

 	GetSecrets(opts basictypes.SecretListOptions) ([]types.Secret, error)

 	CreateSecret(s types.SecretSpec) (string, error)

 	RemoveSecret(idOrName string) error

 	GetSecret(id string) (types.Secret, error)

 	UpdateSecret(idOrName string, version uint64, spec types.SecretSpec) error

-

 	GetConfigs(opts basictypes.ConfigListOptions) ([]types.Config, error)

 	CreateConfig(s types.ConfigSpec) (string, error)

 	RemoveConfig(id string) error

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

 )

 func TestAdjustForAPIVersion(t *testing.T) {

-	var (

-		expectedSysctls = map[string]string{"foo": "bar"}

-	)

+	expectedSysctls := map[string]string{"foo": "bar"}

 	// testing the negative -- does this leave everything else alone? -- is

 	// prohibitively time-consuming to write, because it would need an object

 	// with literally every field filled in.

@@ -78,7 +78,6 @@ func TestGetVolumeByNameFoundRegular(t *testing.T) {

 	v := &volumeRouter{

 		backend: &fakeVolumeBackend{

 			volumes: map[string]*volume.Volume{

-

 				"volume1": {

 					Name: "volume1",

 				},

@@ -108,6 +107,7 @@ func TestGetVolumeByNameFoundSwarm(t *testing.T) {

 	_, err := callGetVolume(v, "volume1")

 	assert.NilError(t, err)

 }

+

 func TestListVolumes(t *testing.T) {

 	v := &volumeRouter{

 		backend: &fakeVolumeBackend{