podmanv2 mount and umount

add the ability to mount and unmount containers for the local client only

Signed-off-by: Brent Baude <bbaude@redhat.com>

cmd/podmanV2/containers/mount.go

@@ -0,0 +1,121 @@
+package containers
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"text/tabwriter"
+	"text/template"
+
+	"github.com/containers/libpod/cmd/podmanV2/parse"
+	"github.com/containers/libpod/cmd/podmanV2/registry"
+	"github.com/containers/libpod/cmd/podmanV2/utils"
+	"github.com/containers/libpod/pkg/domain/entities"
+	"github.com/spf13/cobra"
+)
+
+var (
+	mountDescription = `podman mount
+    Lists all mounted containers mount points if no container is specified
+
+  podman mount CONTAINER-NAME-OR-ID
+    Mounts the specified container and outputs the mountpoint
+`
+
+	mountCommand = &cobra.Command{
+		Use:     "mount [flags] [CONTAINER]",
+		Short:   "Mount a working container's root filesystem",
+		Long:    mountDescription,
+		PreRunE: preRunE,
+		RunE:    mount,
+		Args: func(cmd *cobra.Command, args []string) error {
+			return parse.CheckAllLatestAndCIDFile(cmd, args, true, false)
+		},
+	}
+)
+
+var (
+	mountOpts entities.ContainerMountOptions
+)
+
+func init() {
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Mode:    []entities.EngineMode{entities.ABIMode},
+		Command: mountCommand,
+	})
+	flags := mountCommand.Flags()
+	flags.BoolVarP(&mountOpts.All, "all", "a", false, "Mount all containers")
+	flags.StringVar(&mountOpts.Format, "format", "", "Change the output format to Go template")
+	flags.BoolVarP(&mountOpts.Latest, "latest", "l", false, "Act on the latest container podman is aware of")
+	flags.BoolVar(&mountOpts.NoTruncate, "notruncate", false, "Do not truncate output")
+}
+
+func mount(cmd *cobra.Command, args []string) error {
+	var (
+		errs utils.OutputErrors
+		mrs  []mountReporter
+	)
+	reports, err := registry.ContainerEngine().ContainerMount(registry.GetContext(), args, mountOpts)
+	if err != nil {
+		return err
+	}
+	if len(args) > 0 || mountOpts.Latest || mountOpts.All {
+		for _, r := range reports {
+			if r.Err == nil {
+				fmt.Println(r.Path)
+				continue
+			}
+			errs = append(errs, r.Err)
+		}
+		return errs.PrintErrors()
+	}
+	if mountOpts.Format == "json" {
+		return printJSON(reports)
+	}
+	for _, r := range reports {
+		mrs = append(mrs, mountReporter{r})
+	}
+	row := "{{.ID}} {{.Path}}"
+	format := "{{range . }}" + row + "{{end}}"
+	tmpl, err := template.New("mounts").Parse(format)
+	if err != nil {
+		return err
+	}
+	w := tabwriter.NewWriter(os.Stdout, 8, 2, 2, ' ', 0)
+	defer w.Flush()
+	return tmpl.Execute(w, mrs)
+}
+
+func printJSON(reports []*entities.ContainerMountReport) error {
+	type jreport struct {
+		ID         string `json:"id"`
+		Names      []string
+		Mountpoint string `json:"mountpoint"`
+	}
+	var jreports []jreport
+
+	for _, r := range reports {
+		jreports = append(jreports, jreport{
+			ID:         r.Id,
+			Names:      []string{r.Name},
+			Mountpoint: r.Path,
+		})
+	}
+	b, err := json.MarshalIndent(jreports, "", " ")
+	if err != nil {
+		return err
+	}
+	fmt.Println(string(b))
+	return nil
+}
+
+type mountReporter struct {
+	*entities.ContainerMountReport
+}
+
+func (m mountReporter) ID() string {
+	if mountOpts.NoTruncate {
+		return m.Id
+	}
+	return m.Id[0:12]
+}

cmd/podmanV2/containers/unmount.go

@@ -0,0 +1,65 @@
+package containers
+
+import (
+	"fmt"
+
+	"github.com/containers/libpod/cmd/podmanV2/parse"
+	"github.com/containers/libpod/cmd/podmanV2/registry"
+	"github.com/containers/libpod/cmd/podmanV2/utils"
+	"github.com/containers/libpod/pkg/domain/entities"
+	"github.com/spf13/cobra"
+)
+
+var (
+	description = `Container storage increments a mount counter each time a container is mounted.
+
+  When a container is unmounted, the mount counter is decremented. The container's root filesystem is physically unmounted only when the mount counter reaches zero indicating no other processes are using the mount.
+
+  An unmount can be forced with the --force flag.
+`
+	umountCommand = &cobra.Command{
+		Use:     "umount [flags] CONTAINER [CONTAINER...]",
+		Aliases: []string{"unmount"},
+		Short:   "Unmounts working container's root filesystem",
+		Long:    description,
+		RunE:    unmount,
+		PreRunE: preRunE,
+		Args: func(cmd *cobra.Command, args []string) error {
+			return parse.CheckAllLatestAndCIDFile(cmd, args, false, false)
+		},
+		Example: `podman umount ctrID
+  podman umount ctrID1 ctrID2 ctrID3
+  podman umount --all`,
+	}
+)
+
+var (
+	unmountOpts entities.ContainerUnmountOptions
+)
+
+func init() {
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Mode:    []entities.EngineMode{entities.ABIMode},
+		Command: umountCommand,
+	})
+	flags := umountCommand.Flags()
+	flags.BoolVarP(&unmountOpts.All, "all", "a", false, "Umount all of the currently mounted containers")
+	flags.BoolVarP(&unmountOpts.Force, "force", "f", false, "Force the complete umount all of the currently mounted containers")
+	flags.BoolVarP(&unmountOpts.Latest, "latest", "l", false, "Act on the latest container podman is aware of")
+}
+
+func unmount(cmd *cobra.Command, args []string) error {
+	var errs utils.OutputErrors
+	reports, err := registry.ContainerEngine().ContainerUnmount(registry.GetContext(), args, unmountOpts)
+	if err != nil {
+		return err
+	}
+	for _, r := range reports {
+		if r.Err == nil {
+			fmt.Println(r.Id)
+		} else {
+			errs = append(errs, r.Err)
+		}
+	}
+	return errs.PrintErrors()
+}

pkg/domain/entities/containers.go

@@ -297,3 +297,33 @@ type ContainerInitReport struct {
 	Err error
 	Id  string
 }
+
+//ContainerMountOptions describes the input values for mounting containers
+// in the CLI
+type ContainerMountOptions struct {
+	All        bool
+	Format     string
+	Latest     bool
+	NoTruncate bool
+}
+
+// ContainerUnmountOptions are the options from the cli for unmounting
+type ContainerUnmountOptions struct {
+	All    bool
+	Force  bool
+	Latest bool
+}
+
+// ContainerMountReport describes the response from container mount
+type ContainerMountReport struct {
+	Err  error
+	Id   string
+	Name string
+	Path string
+}
+
+// ContainerUnmountReport describes the response from umounting a container
+type ContainerUnmountReport struct {
+	Err error
+	Id  string
+}

pkg/domain/entities/engine_container.go

@@ -21,6 +21,7 @@ type ContainerEngine interface {
 	ContainerInspect(ctx context.Context, namesOrIds []string, options InspectOptions) ([]*ContainerInspectReport, error)
 	ContainerKill(ctx context.Context, namesOrIds []string, options KillOptions) ([]*KillReport, error)
 	ContainerList(ctx context.Context, options ContainerListOptions) ([]ListContainer, error)
+	ContainerMount(ctx context.Context, nameOrIds []string, options ContainerMountOptions) ([]*ContainerMountReport, error)
 	ContainerPause(ctx context.Context, namesOrIds []string, options PauseUnPauseOptions) ([]*PauseUnpauseReport, error)
 	ContainerLogs(ctx context.Context, containers []string, options ContainerLogsOptions) error
 	ContainerRestart(ctx context.Context, namesOrIds []string, options RestartOptions) ([]*RestartReport, error)
@@ -30,6 +31,7 @@ type ContainerEngine interface {
 	ContainerStart(ctx context.Context, namesOrIds []string, options ContainerStartOptions) ([]*ContainerStartReport, error)
 	ContainerStop(ctx context.Context, namesOrIds []string, options StopOptions) ([]*StopReport, error)
 	ContainerTop(ctx context.Context, options TopOptions) (*StringSliceReport, error)
+	ContainerUnmount(ctx context.Context, nameOrIds []string, options ContainerUnmountOptions) ([]*ContainerUnmountReport, error)
 	ContainerUnpause(ctx context.Context, namesOrIds []string, options PauseUnPauseOptions) ([]*PauseUnpauseReport, error)
 	ContainerWait(ctx context.Context, namesOrIds []string, options WaitOptions) ([]WaitReport, error)
 	HealthCheckRun(ctx context.Context, nameOrId string, options HealthCheckOptions) (*define.HealthCheckResults, error)

pkg/domain/infra/abi/containers.go

@@ -6,6 +6,7 @@ import (
 	"context"
 	"fmt"
 	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 	"sync"
@@ -21,9 +22,11 @@ import (
 	"github.com/containers/libpod/pkg/domain/entities"
 	"github.com/containers/libpod/pkg/domain/infra/abi/terminal"
 	"github.com/containers/libpod/pkg/ps"
+	"github.com/containers/libpod/pkg/rootless"
 	"github.com/containers/libpod/pkg/signal"
 	"github.com/containers/libpod/pkg/specgen"
 	"github.com/containers/libpod/pkg/specgen/generate"
+	"github.com/containers/storage"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
@@ -808,3 +811,85 @@ func (ic *ContainerEngine) ContainerInit(ctx context.Context, namesOrIds []strin
 	}
 	return reports, nil
 }
+
+func (ic *ContainerEngine) ContainerMount(ctx context.Context, nameOrIds []string, options entities.ContainerMountOptions) ([]*entities.ContainerMountReport, error) {
+	if os.Geteuid() != 0 {
+		if driver := ic.Libpod.StorageConfig().GraphDriverName; driver != "vfs" {
+			// Do not allow to mount a graphdriver that is not vfs if we are creating the userns as part
+			// of the mount command.
+			return nil, fmt.Errorf("cannot mount using driver %s in rootless mode", driver)
+		}
+
+		became, ret, err := rootless.BecomeRootInUserNS("")
+		if err != nil {
+			return nil, err
+		}
+		if became {
+			os.Exit(ret)
+		}
+	}
+	var reports []*entities.ContainerMountReport
+	ctrs, err := getContainersByContext(options.All, options.Latest, nameOrIds, ic.Libpod)
+	if err != nil {
+		return nil, err
+	}
+	for _, ctr := range ctrs {
+		report := entities.ContainerMountReport{Id: ctr.ID()}
+		report.Path, report.Err = ctr.Mount()
+		reports = append(reports, &report)
+	}
+	if len(reports) > 0 {
+		return reports, nil
+	}
+
+	// No containers were passed, so we send back what is mounted
+	ctrs, err = getContainersByContext(true, false, []string{}, ic.Libpod)
+	if err != nil {
+		return nil, err
+	}
+	for _, ctr := range ctrs {
+		mounted, path, err := ctr.Mounted()
+		if err != nil {
+			return nil, err
+		}
+
+		if mounted {
+			reports = append(reports, &entities.ContainerMountReport{
+				Id:   ctr.ID(),
+				Name: ctr.Name(),
+				Path: path,
+			})
+		}
+	}
+	return reports, nil
+}
+
+func (ic *ContainerEngine) ContainerUnmount(ctx context.Context, nameOrIds []string, options entities.ContainerUnmountOptions) ([]*entities.ContainerUnmountReport, error) {
+	var reports []*entities.ContainerUnmountReport
+	ctrs, err := getContainersByContext(options.All, options.Latest, nameOrIds, ic.Libpod)
+	if err != nil {
+		return nil, err
+	}
+	for _, ctr := range ctrs {
+		state, err := ctr.State()
+		if err != nil {
+			logrus.Debugf("Error umounting container %s state: %s", ctr.ID(), err.Error())
+			continue
+		}
+		if state == define.ContainerStateRunning {
+			logrus.Debugf("Error umounting container %s, is running", ctr.ID())
+			continue
+		}
+
+		report := entities.ContainerUnmountReport{Id: ctr.ID()}
+		if err := ctr.Unmount(options.Force); err != nil {
+			if options.All && errors.Cause(err) == storage.ErrLayerNotMounted {
+				logrus.Debugf("Error umounting container %s, storage.ErrLayerNotMounted", ctr.ID())
+				continue
+			}
+			report.Err = errors.Wrapf(err, "error unmounting container %s", ctr.ID())
+		}
+		reports = append(reports, &report)
+	}
+	return reports, nil
+}

pkg/domain/infra/tunnel/containers.go

@@ -354,3 +354,11 @@ func (ic *ContainerEngine) ContainerInit(ctx context.Context, namesOrIds []strin
 	}
 	return reports, nil
 }
+
+func (ic *ContainerEngine) ContainerMount(ctx context.Context, nameOrIds []string, options entities.ContainerMountOptions) ([]*entities.ContainerMountReport, error) {
+	return nil, errors.New("mounting containers is not supported for remote clients")
+}
+
+func (ic *ContainerEngine) ContainerUnmount(ctx context.Context, nameOrIds []string, options entities.ContainerUnmountOptions) ([]*entities.ContainerUnmountReport, error) {
+	return nil, errors.New("unmounting containers is not supported for remote clients")
+}