Merge pull request #26108 from mlaventure/data-mngt

New Data Management commands

command/container/cmd.go

@@ -44,6 +44,7 @@ func NewContainerCommand(dockerCli *command.DockerCli) *cobra.Command {
 		NewWaitCommand(dockerCli),
 		newListCommand(dockerCli),
 		newInspectCommand(dockerCli),
+		NewPruneCommand(dockerCli),
 	)
 	return cmd
 }

command/container/prune.go

@@ -0,0 +1,74 @@
+package container
+
+import (
+	"fmt"
+
+	"golang.org/x/net/context"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/cli"
+	"github.com/docker/docker/cli/command"
+	units "github.com/docker/go-units"
+	"github.com/spf13/cobra"
+)
+
+type pruneOptions struct {
+	force bool
+}
+
+// NewPruneCommand returns a new cobra prune command for containers
+func NewPruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	var opts pruneOptions
+
+	cmd := &cobra.Command{
+		Use:   "prune",
+		Short: "Remove all stopped containers",
+		Args:  cli.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			spaceReclaimed, output, err := runPrune(dockerCli, opts)
+			if err != nil {
+				return err
+			}
+			if output != "" {
+				fmt.Fprintln(dockerCli.Out(), output)
+			}
+			fmt.Fprintln(dockerCli.Out(), "Total reclaimed space:", units.HumanSize(float64(spaceReclaimed)))
+			return nil
+		},
+	}
+
+	flags := cmd.Flags()
+	flags.BoolVarP(&opts.force, "force", "f", false, "Do not prompt for confirmation")
+
+	return cmd
+}
+
+const warning = `WARNING! This will remove all stopped containers.
+Are you sure you want to continue? [y/N] `
+
+func runPrune(dockerCli *command.DockerCli, opts pruneOptions) (spaceReclaimed uint64, output string, err error) {
+	if !opts.force && !command.PromptForConfirmation(dockerCli.In(), dockerCli.Out(), warning) {
+		return
+	}
+
+	report, err := dockerCli.Client().ContainersPrune(context.Background(), types.ContainersPruneConfig{})
+	if err != nil {
+		return
+	}
+
+	if len(report.ContainersDeleted) > 0 {
+		output = "Deleted Containers:"
+		for _, id := range report.ContainersDeleted {
+			output += id + "\n"
+		}
+		spaceReclaimed = report.SpaceReclaimed
+	}
+
+	return
+}
+
+// RunPrune call the Container Prune API
+// This returns the amount of space reclaimed and a detailed output string
+func RunPrune(dockerCli *command.DockerCli) (uint64, string, error) {
+	return runPrune(dockerCli, pruneOptions{force: true})
+}

command/container/stats.go

@@ -15,7 +15,6 @@ import (
 	"github.com/docker/docker/cli"
 	"github.com/docker/docker/cli/command"
 	"github.com/docker/docker/cli/command/formatter"
-	"github.com/docker/docker/cli/command/system"
 	"github.com/spf13/cobra"
 )
 
@@ -110,7 +109,7 @@ func runStats(dockerCli *command.DockerCli, opts *statsOptions) error {
 		// retrieving the list of running containers to avoid a race where we
 		// would "miss" a creation.
 		started := make(chan struct{})
-		eh := system.InitEventHandler()
+		eh := command.InitEventHandler()
 		eh.Handle("create", func(e events.Message) {
 			if opts.all {
 				s := formatter.NewContainerStats(e.ID[:12], daemonOSType)

command/events_utils.go

@@ -1,4 +1,4 @@
-package system
+package command
 
 import (
 	"sync"

command/formatter/container.go

@@ -23,6 +23,7 @@ const (
 	statusHeader      = "STATUS"
 	portsHeader       = "PORTS"
 	mountsHeader      = "MOUNTS"
+	localVolumes      = "LOCAL VOLUMES"
 )
 
 // NewContainerFormat returns a Format for rendering using a Context
@@ -199,3 +200,16 @@ func (c *containerContext) Mounts() string {
 	}
 	return strings.Join(mounts, ",")
 }
+
+func (c *containerContext) LocalVolumes() string {
+	c.AddHeader(localVolumes)
+
+	count := 0
+	for _, m := range c.c.Mounts {
+		if m.Driver == "local" {
+			count++
+		}
+	}
+
+	return fmt.Sprintf("%d", count)
+}

command/formatter/disk_usage.go

@@ -0,0 +1,331 @@
+package formatter
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"text/template"
+
+	"github.com/docker/distribution/reference"
+	"github.com/docker/docker/api/types"
+	units "github.com/docker/go-units"
+)
+
+const (
+	defaultDiskUsageImageTableFormat     = "table {{.Repository}}\t{{.Tag}}\t{{.ID}}\t{{.CreatedSince}} ago\t{{.VirtualSize}}\t{{.SharedSize}}\t{{.UniqueSize}}\t{{.Containers}}"
+	defaultDiskUsageContainerTableFormat = "table {{.ID}}\t{{.Image}}\t{{.Command}}\t{{.LocalVolumes}}\t{{.Size}}\t{{.RunningFor}} ago\t{{.Status}}\t{{.Names}}"
+	defaultDiskUsageVolumeTableFormat    = "table {{.Name}}\t{{.Links}}\t{{.Size}}"
+	defaultDiskUsageTableFormat          = "table {{.Type}}\t{{.TotalCount}}\t{{.Active}}\t{{.Size}}\t{{.Reclaimable}}"
+
+	typeHeader        = "TYPE"
+	totalHeader       = "TOTAL"
+	activeHeader      = "ACTIVE"
+	reclaimableHeader = "RECLAIMABLE"
+	containersHeader  = "CONTAINERS"
+	sharedSizeHeader  = "SHARED SIZE"
+	uniqueSizeHeader  = "UNIQUE SiZE"
+)
+
+// DiskUsageContext contains disk usage specific information required by the formater, encapsulate a Context struct.
+type DiskUsageContext struct {
+	Context
+	Verbose    bool
+	LayersSize int64
+	Images     []*types.Image
+	Containers []*types.Container
+	Volumes    []*types.Volume
+}
+
+func (ctx *DiskUsageContext) startSubsection(format string) (*template.Template, error) {
+	ctx.buffer = bytes.NewBufferString("")
+	ctx.header = ""
+	ctx.Format = Format(format)
+	ctx.preFormat()
+
+	return ctx.parseFormat()
+}
+
+func (ctx *DiskUsageContext) Write() {
+	if ctx.Verbose == false {
+		ctx.buffer = bytes.NewBufferString("")
+		ctx.Format = defaultDiskUsageTableFormat
+		ctx.preFormat()
+
+		tmpl, err := ctx.parseFormat()
+		if err != nil {
+			return
+		}
+
+		err = ctx.contextFormat(tmpl, &diskUsageImagesContext{
+			totalSize: ctx.LayersSize,
+			images:    ctx.Images,
+		})
+		if err != nil {
+			return
+		}
+		err = ctx.contextFormat(tmpl, &diskUsageContainersContext{
+			containers: ctx.Containers,
+		})
+		if err != nil {
+			return
+		}
+
+		err = ctx.contextFormat(tmpl, &diskUsageVolumesContext{
+			volumes: ctx.Volumes,
+		})
+		if err != nil {
+			return
+		}
+
+		ctx.postFormat(tmpl, &diskUsageContainersContext{containers: []*types.Container{}})
+
+		return
+	}
+
+	// First images
+	tmpl, err := ctx.startSubsection(defaultDiskUsageImageTableFormat)
+	if err != nil {
+		return
+	}
+
+	ctx.Output.Write([]byte("Images space usage:\n\n"))
+	for _, i := range ctx.Images {
+		repo := "<none>"
+		tag := "<none>"
+		if len(i.RepoTags) > 0 && !isDangling(*i) {
+			// Only show the first tag
+			ref, err := reference.ParseNamed(i.RepoTags[0])
+			if err != nil {
+				continue
+			}
+			if nt, ok := ref.(reference.NamedTagged); ok {
+				repo = ref.Name()
+				tag = nt.Tag()
+			}
+		}
+
+		err = ctx.contextFormat(tmpl, &imageContext{
+			repo:  repo,
+			tag:   tag,
+			trunc: true,
+			i:     *i,
+		})
+		if err != nil {
+			return
+		}
+	}
+	ctx.postFormat(tmpl, &imageContext{})
+
+	// Now containers
+	ctx.Output.Write([]byte("\nContainers space usage:\n\n"))
+	tmpl, err = ctx.startSubsection(defaultDiskUsageContainerTableFormat)
+	if err != nil {
+		return
+	}
+	for _, c := range ctx.Containers {
+		// Don't display the virtual size
+		c.SizeRootFs = 0
+		err = ctx.contextFormat(tmpl, &containerContext{
+			trunc: true,
+			c:     *c,
+		})
+		if err != nil {
+			return
+		}
+	}
+	ctx.postFormat(tmpl, &containerContext{})
+
+	// And volumes
+	ctx.Output.Write([]byte("\nLocal Volumes space usage:\n\n"))
+	tmpl, err = ctx.startSubsection(defaultDiskUsageVolumeTableFormat)
+	if err != nil {
+		return
+	}
+	for _, v := range ctx.Volumes {
+		err = ctx.contextFormat(tmpl, &volumeContext{
+			v: *v,
+		})
+		if err != nil {
+			return
+		}
+	}
+	ctx.postFormat(tmpl, &volumeContext{v: types.Volume{}})
+}
+
+type diskUsageImagesContext struct {
+	HeaderContext
+	totalSize int64
+	images    []*types.Image
+}
+
+func (c *diskUsageImagesContext) Type() string {
+	c.AddHeader(typeHeader)
+	return "Images"
+}
+
+func (c *diskUsageImagesContext) TotalCount() string {
+	c.AddHeader(totalHeader)
+	return fmt.Sprintf("%d", len(c.images))
+}
+
+func (c *diskUsageImagesContext) Active() string {
+	c.AddHeader(activeHeader)
+	used := 0
+	for _, i := range c.images {
+		if i.Containers > 0 {
+			used++
+		}
+	}
+
+	return fmt.Sprintf("%d", used)
+}
+
+func (c *diskUsageImagesContext) Size() string {
+	c.AddHeader(sizeHeader)
+	return units.HumanSize(float64(c.totalSize))
+
+}
+
+func (c *diskUsageImagesContext) Reclaimable() string {
+	var used int64
+
+	c.AddHeader(reclaimableHeader)
+	for _, i := range c.images {
+		if i.Containers != 0 {
+			used += i.Size
+		}
+	}
+
+	reclaimable := c.totalSize - used
+	if c.totalSize > 0 {
+		return fmt.Sprintf("%s (%v%%)", units.HumanSize(float64(reclaimable)), (reclaimable*100)/c.totalSize)
+	}
+	return fmt.Sprintf("%s", units.HumanSize(float64(reclaimable)))
+}
+
+type diskUsageContainersContext struct {
+	HeaderContext
+	verbose    bool
+	containers []*types.Container
+}
+
+func (c *diskUsageContainersContext) Type() string {
+	c.AddHeader(typeHeader)
+	return "Containers"
+}
+
+func (c *diskUsageContainersContext) TotalCount() string {
+	c.AddHeader(totalHeader)
+	return fmt.Sprintf("%d", len(c.containers))
+}
+
+func (c *diskUsageContainersContext) isActive(container types.Container) bool {
+	return strings.Contains(container.State, "running") ||
+		strings.Contains(container.State, "paused") ||
+		strings.Contains(container.State, "restarting")
+}
+
+func (c *diskUsageContainersContext) Active() string {
+	c.AddHeader(activeHeader)
+	used := 0
+	for _, container := range c.containers {
+		if c.isActive(*container) {
+			used++
+		}
+	}
+
+	return fmt.Sprintf("%d", used)
+}
+
+func (c *diskUsageContainersContext) Size() string {
+	var size int64
+
+	c.AddHeader(sizeHeader)
+	for _, container := range c.containers {
+		size += container.SizeRw
+	}
+
+	return units.HumanSize(float64(size))
+}
+
+func (c *diskUsageContainersContext) Reclaimable() string {
+	var reclaimable int64
+	var totalSize int64
+
+	c.AddHeader(reclaimableHeader)
+	for _, container := range c.containers {
+		if !c.isActive(*container) {
+			reclaimable += container.SizeRw
+		}
+		totalSize += container.SizeRw
+	}
+
+	if totalSize > 0 {
+		return fmt.Sprintf("%s (%v%%)", units.HumanSize(float64(reclaimable)), (reclaimable*100)/totalSize)
+	}
+
+	return fmt.Sprintf("%s", units.HumanSize(float64(reclaimable)))
+}
+
+type diskUsageVolumesContext struct {
+	HeaderContext
+	verbose bool
+	volumes []*types.Volume
+}
+
+func (c *diskUsageVolumesContext) Type() string {
+	c.AddHeader(typeHeader)
+	return "Local Volumes"
+}
+
+func (c *diskUsageVolumesContext) TotalCount() string {
+	c.AddHeader(totalHeader)
+	return fmt.Sprintf("%d", len(c.volumes))
+}
+
+func (c *diskUsageVolumesContext) Active() string {
+	c.AddHeader(activeHeader)
+
+	used := 0
+	for _, v := range c.volumes {
+		if v.RefCount > 0 {
+			used++
+		}
+	}
+
+	return fmt.Sprintf("%d", used)
+}
+
+func (c *diskUsageVolumesContext) Size() string {
+	var size int64
+
+	c.AddHeader(sizeHeader)
+	for _, v := range c.volumes {
+		if v.Size != -1 {
+			size += v.Size
+		}
+	}
+
+	return units.HumanSize(float64(size))
+}
+
+func (c *diskUsageVolumesContext) Reclaimable() string {
+	var reclaimable int64
+	var totalSize int64
+
+	c.AddHeader(reclaimableHeader)
+	for _, v := range c.volumes {
+		if v.Size != -1 {
+			if v.RefCount == 0 {
+				reclaimable += v.Size
+			}
+			totalSize += v.Size
+		}
+	}
+
+	if totalSize > 0 {
+		return fmt.Sprintf("%s (%v%%)", units.HumanSize(float64(reclaimable)), (reclaimable*100)/totalSize)
+	}
+
+	return fmt.Sprintf("%s", units.HumanSize(float64(reclaimable)))
+}

command/formatter/image.go

@@ -1,6 +1,7 @@
 package formatter
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/docker/docker/api/types"
@@ -225,5 +226,35 @@ func (c *imageContext) CreatedAt() string {
 
 func (c *imageContext) Size() string {
 	c.AddHeader(sizeHeader)
-	return units.HumanSizeWithPrecision(float64(c.i.Size), 3)
+	//NOTE: For backward compatibility we need to return VirtualSize
+	return units.HumanSizeWithPrecision(float64(c.i.VirtualSize), 3)
+}
+
+func (c *imageContext) Containers() string {
+	c.AddHeader(containersHeader)
+	if c.i.Containers == -1 {
+		return "N/A"
+	}
+	return fmt.Sprintf("%d", c.i.Containers)
+}
+
+func (c *imageContext) VirtualSize() string {
+	c.AddHeader(sizeHeader)
+	return units.HumanSize(float64(c.i.VirtualSize))
+}
+
+func (c *imageContext) SharedSize() string {
+	c.AddHeader(sharedSizeHeader)
+	if c.i.SharedSize == -1 {
+		return "N/A"
+	}
+	return units.HumanSize(float64(c.i.SharedSize))
+}
+
+func (c *imageContext) UniqueSize() string {
+	c.AddHeader(uniqueSizeHeader)
+	if c.i.Size == -1 {
+		return "N/A"
+	}
+	return units.HumanSize(float64(c.i.Size))
 }

command/formatter/image_test.go

@@ -32,7 +32,7 @@ func TestImageContext(t *testing.T) {
 			trunc: false,
 		}, imageID, imageIDHeader, ctx.ID},
 		{imageContext{
-			i:     types.Image{Size: 10},
+			i:     types.Image{Size: 10, VirtualSize: 10},
 			trunc: true,
 		}, "10 B", sizeHeader, ctx.Size},
 		{imageContext{

command/formatter/volume.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"github.com/docker/docker/api/types"
+	units "github.com/docker/go-units"
 )
 
 const (
@@ -12,6 +13,7 @@ const (
 	defaultVolumeTableFormat = "table {{.Driver}}\t{{.Name}}"
 
 	mountpointHeader = "MOUNTPOINT"
+	linksHeader      = "LINKS"
 	// Status header ?
 )
 
@@ -96,3 +98,19 @@ func (c *volumeContext) Label(name string) string {
 	}
 	return c.v.Labels[name]
 }
+
+func (c *volumeContext) Links() string {
+	c.AddHeader(linksHeader)
+	if c.v.Size == -1 {
+		return "N/A"
+	}
+	return fmt.Sprintf("%d", c.v.RefCount)
+}
+
+func (c *volumeContext) Size() string {
+	c.AddHeader(sizeHeader)
+	if c.v.Size == -1 {
+		return "N/A"
+	}
+	return units.HumanSize(float64(c.v.Size))
+}

command/image/cmd.go

@@ -31,6 +31,8 @@ func NewImageCommand(dockerCli *command.DockerCli) *cobra.Command {
 		newListCommand(dockerCli),
 		newRemoveCommand(dockerCli),
 		newInspectCommand(dockerCli),
+		NewPruneCommand(dockerCli),
 	)
+
 	return cmd
 }

command/image/prune.go

@@ -0,0 +1,90 @@
+package image
+
+import (
+	"fmt"
+
+	"golang.org/x/net/context"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/cli"
+	"github.com/docker/docker/cli/command"
+	units "github.com/docker/go-units"
+	"github.com/spf13/cobra"
+)
+
+type pruneOptions struct {
+	force bool
+	all   bool
+}
+
+// NewPruneCommand returns a new cobra prune command for images
+func NewPruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	var opts pruneOptions
+
+	cmd := &cobra.Command{
+		Use:   "prune",
+		Short: "Remove unused images",
+		Args:  cli.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			spaceReclaimed, output, err := runPrune(dockerCli, opts)
+			if err != nil {
+				return err
+			}
+			if output != "" {
+				fmt.Fprintln(dockerCli.Out(), output)
+			}
+			fmt.Fprintln(dockerCli.Out(), "Total reclaimed space:", units.HumanSize(float64(spaceReclaimed)))
+			return nil
+		},
+	}
+
+	flags := cmd.Flags()
+	flags.BoolVarP(&opts.force, "force", "f", false, "Do not prompt for confirmation")
+	flags.BoolVarP(&opts.all, "all", "a", false, "Remove all unused images, not just dangling ones")
+
+	return cmd
+}
+
+const (
+	allImageWarning = `WARNING! This will remove all images without at least one container associated to them.
+Are you sure you want to continue?`
+	danglingWarning = `WARNING! This will remove all dangling images.
+Are you sure you want to continue?`
+)
+
+func runPrune(dockerCli *command.DockerCli, opts pruneOptions) (spaceReclaimed uint64, output string, err error) {
+	warning := danglingWarning
+	if opts.all {
+		warning = allImageWarning
+	}
+	if !opts.force && !command.PromptForConfirmation(dockerCli.In(), dockerCli.Out(), warning) {
+		return
+	}
+
+	report, err := dockerCli.Client().ImagesPrune(context.Background(), types.ImagesPruneConfig{
+		DanglingOnly: !opts.all,
+	})
+	if err != nil {
+		return
+	}
+
+	if len(report.ImagesDeleted) > 0 {
+		output = "Deleted Images:\n"
+		for _, st := range report.ImagesDeleted {
+			if st.Untagged != "" {
+				output += fmt.Sprintln("untagged:", st.Untagged)
+			} else {
+				output += fmt.Sprintln("deleted:", st.Deleted)
+			}
+		}
+		spaceReclaimed = report.SpaceReclaimed
+	}
+
+	return
+}
+
+// RunPrune call the Image Prune API
+// This returns the amount of space reclaimed and a detailed output string
+func RunPrune(dockerCli *command.DockerCli, all bool) (uint64, string, error) {
+	return runPrune(dockerCli, pruneOptions{force: true, all: all})
+}

command/prune/prune.go

@@ -0,0 +1,39 @@
+package prune
+
+import (
+	"github.com/docker/docker/cli/command"
+	"github.com/docker/docker/cli/command/container"
+	"github.com/docker/docker/cli/command/image"
+	"github.com/docker/docker/cli/command/volume"
+	"github.com/spf13/cobra"
+)
+
+// NewContainerPruneCommand return a cobra prune command for containers
+func NewContainerPruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	return container.NewPruneCommand(dockerCli)
+}
+
+// NewVolumePruneCommand return a cobra prune command for volumes
+func NewVolumePruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	return volume.NewPruneCommand(dockerCli)
+}
+
+// NewImagePruneCommand return a cobra prune command for images
+func NewImagePruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	return image.NewPruneCommand(dockerCli)
+}
+
+// RunContainerPrune execute a prune command for containers
+func RunContainerPrune(dockerCli *command.DockerCli) (uint64, string, error) {
+	return container.RunPrune(dockerCli)
+}
+
+// RunVolumePrune execute a prune command for volumes
+func RunVolumePrune(dockerCli *command.DockerCli) (uint64, string, error) {
+	return volume.RunPrune(dockerCli)
+}
+
+// RunImagePrune execute a prune command for images
+func RunImagePrune(dockerCli *command.DockerCli, all bool) (uint64, string, error) {
+	return image.RunPrune(dockerCli, all)
+}

command/system/cmd.go

@@ -22,6 +22,8 @@ func NewSystemCommand(dockerCli *command.DockerCli) *cobra.Command {
 	cmd.AddCommand(
 		NewEventsCommand(dockerCli),
 		NewInfoCommand(dockerCli),
+		NewDiskUsageCommand(dockerCli),
+		NewPruneCommand(dockerCli),
 	)
 	return cmd
 }

command/system/df.go

@@ -0,0 +1,55 @@
+package system
+
+import (
+	"github.com/docker/docker/cli"
+	"github.com/docker/docker/cli/command"
+	"github.com/docker/docker/cli/command/formatter"
+	"github.com/spf13/cobra"
+	"golang.org/x/net/context"
+)
+
+type diskUsageOptions struct {
+	verbose bool
+}
+
+// NewDiskUsageCommand creates a new cobra.Command for `docker df`
+func NewDiskUsageCommand(dockerCli *command.DockerCli) *cobra.Command {
+	var opts diskUsageOptions
+
+	cmd := &cobra.Command{
+		Use:   "df [OPTIONS]",
+		Short: "Show docker disk usage",
+		Args:  cli.RequiresMaxArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runDiskUsage(dockerCli, opts)
+		},
+	}
+
+	flags := cmd.Flags()
+
+	flags.BoolVarP(&opts.verbose, "verbose", "v", false, "Show detailed information on space usage")
+
+	return cmd
+}
+
+func runDiskUsage(dockerCli *command.DockerCli, opts diskUsageOptions) error {
+	du, err := dockerCli.Client().DiskUsage(context.Background())
+	if err != nil {
+		return err
+	}
+
+	duCtx := formatter.DiskUsageContext{
+		Context: formatter.Context{
+			Output: dockerCli.Out(),
+		},
+		LayersSize: du.LayersSize,
+		Images:     du.Images,
+		Containers: du.Containers,
+		Volumes:    du.Volumes,
+		Verbose:    opts.verbose,
+	}
+
+	duCtx.Write()
+
+	return nil
+}

command/system/prune.go

@@ -0,0 +1,90 @@
+package system
+
+import (
+	"fmt"
+
+	"github.com/docker/docker/cli"
+	"github.com/docker/docker/cli/command"
+	"github.com/docker/docker/cli/command/prune"
+	units "github.com/docker/go-units"
+	"github.com/spf13/cobra"
+)
+
+type pruneOptions struct {
+	force bool
+	all   bool
+}
+
+// NewPruneCommand creates a new cobra.Command for `docker du`
+func NewPruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	var opts pruneOptions
+
+	cmd := &cobra.Command{
+		Use:   "prune [COMMAND]",
+		Short: "Remove unused data.",
+		Args:  cli.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runPrune(dockerCli, opts)
+		},
+	}
+
+	flags := cmd.Flags()
+	flags.BoolVarP(&opts.force, "force", "f", false, "Do not prompt for confirmation")
+	flags.BoolVarP(&opts.all, "all", "a", false, "Remove all unused images not just dangling ones")
+
+	return cmd
+}
+
+const (
+	warning = `WARNING! This will remove:
+	- all stopped containers
+	- all volumes not used by at least one container
+	%s
+Are you sure you want to continue?`
+
+	danglingImageDesc = "- all dangling images"
+	allImageDesc      = `- all images without at least one container associated to them`
+)
+
+func runPrune(dockerCli *command.DockerCli, opts pruneOptions) error {
+	var message string
+
+	if opts.all {
+		message = fmt.Sprintf(warning, allImageDesc)
+	} else {
+		message = fmt.Sprintf(warning, danglingImageDesc)
+	}
+
+	if !opts.force && !command.PromptForConfirmation(dockerCli.In(), dockerCli.Out(), message) {
+		return nil
+	}
+
+	var spaceReclaimed uint64
+
+	for _, pruneFn := range []func(dockerCli *command.DockerCli) (uint64, string, error){
+		prune.RunContainerPrune,
+		prune.RunVolumePrune,
+	} {
+		spc, output, err := pruneFn(dockerCli)
+		if err != nil {
+			return err
+		}
+		if spc > 0 {
+			spaceReclaimed += spc
+			fmt.Fprintln(dockerCli.Out(), output)
+		}
+	}
+
+	spc, output, err := prune.RunImagePrune(dockerCli, opts.all)
+	if err != nil {
+		return err
+	}
+	if spc > 0 {
+		spaceReclaimed += spc
+		fmt.Fprintln(dockerCli.Out(), output)
+	}
+
+	fmt.Fprintln(dockerCli.Out(), "Total reclaimed space:", units.HumanSize(float64(spaceReclaimed)))
+
+	return nil
+}

command/utils.go

@@ -57,3 +57,25 @@ func PrettyPrint(i interface{}) string {
 		return capitalizeFirst(fmt.Sprintf("%s", t))
 	}
 }
+
+// PromptForConfirmation request and check confirmation from user.
+// This will display the provided message followed by ' [y/N] '. If
+// the user input 'y' or 'Y' it returns true other false.  If no
+// message is provided "Are you sure you want to proceeed? [y/N] "
+// will be used instead.
+func PromptForConfirmation(ins *InStream, outs *OutStream, message string) bool {
+	if message == "" {
+		message = "Are you sure you want to proceeed?"
+	}
+	message += " [y/N] "
+
+	fmt.Fprintf(outs, message)
+
+	answer := ""
+	n, _ := fmt.Fscan(ins, &answer)
+	if n != 1 || (answer != "y" && answer != "Y") {
+		return false
+	}
+
+	return true
+}

command/volume/cmd.go

@@ -25,6 +25,7 @@ func NewVolumeCommand(dockerCli *command.DockerCli) *cobra.Command {
 		newInspectCommand(dockerCli),
 		newListCommand(dockerCli),
 		newRemoveCommand(dockerCli),
+		NewPruneCommand(dockerCli),
 	)
 	return cmd
 }

command/volume/prune.go

@@ -0,0 +1,74 @@
+package volume
+
+import (
+	"fmt"
+
+	"golang.org/x/net/context"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/cli"
+	"github.com/docker/docker/cli/command"
+	units "github.com/docker/go-units"
+	"github.com/spf13/cobra"
+)
+
+type pruneOptions struct {
+	force bool
+}
+
+// NewPruneCommand returns a new cobra prune command for volumes
+func NewPruneCommand(dockerCli *command.DockerCli) *cobra.Command {
+	var opts pruneOptions
+
+	cmd := &cobra.Command{
+		Use:   "prune",
+		Short: "Remove all unused volumes",
+		Args:  cli.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			spaceReclaimed, output, err := runPrune(dockerCli, opts)
+			if err != nil {
+				return err
+			}
+			if output != "" {
+				fmt.Fprintln(dockerCli.Out(), output)
+			}
+			fmt.Fprintln(dockerCli.Out(), "Total reclaimed space:", units.HumanSize(float64(spaceReclaimed)))
+			return nil
+		},
+	}
+
+	flags := cmd.Flags()
+	flags.BoolVarP(&opts.force, "force", "f", false, "Do not prompt for confirmation")
+
+	return cmd
+}
+
+const warning = `WARNING! This will remove all volumes not used by at least one container.
+Are you sure you want to continue?`
+
+func runPrune(dockerCli *command.DockerCli, opts pruneOptions) (spaceReclaimed uint64, output string, err error) {
+	if !opts.force && !command.PromptForConfirmation(dockerCli.In(), dockerCli.Out(), warning) {
+		return
+	}
+
+	report, err := dockerCli.Client().VolumesPrune(context.Background(), types.VolumesPruneConfig{})
+	if err != nil {
+		return
+	}
+
+	if len(report.VolumesDeleted) > 0 {
+		output = "Deleted Volumes:\n"
+		for _, id := range report.VolumesDeleted {
+			output += id + "\n"
+		}
+		spaceReclaimed = report.SpaceReclaimed
+	}
+
+	return
+}
+
+// RunPrune call the Volume Prune API
+// This returns the amount of space reclaimed and a detailed output string
+func RunPrune(dockerCli *command.DockerCli) (uint64, string, error) {
+	return runPrune(dockerCli, pruneOptions{force: true})
+}