Implement backend for 'volume inspect'

Begin to separate the internal structures and frontend for
inspect on volumes. We can't rely on keeping internal data
structures for external presentation - separating presentation
and internal data format is good practice.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

9 files changed, 130 insertions, 45 deletions

diff --git a/cmd/podman/varlink/io.podman.varlink b/cmd/podman/varlink/io.podman.varlink
index f5f3250f7..73f4d1609 100644
--- a/cmd/podman/varlink/io.podman.varlink
+++ b/cmd/podman/varlink/io.podman.varlink
@@ -7,8 +7,7 @@ type Volume (
   labels: [string]string,
   mountPoint: string,
   driver: string,
-  options: [string]string,
-  scope: string
+  options: [string]string
 )
 
 type NotImplemented (
diff --git a/cmd/podman/volume_create.go b/cmd/podman/volume_create.go
index 0897ab705..617f701a4 100644
--- a/cmd/podman/volume_create.go
+++ b/cmd/podman/volume_create.go
@@ -38,7 +38,6 @@ func init() {
 	flags.StringVar(&volumeCreateCommand.Driver, "driver", "", "Specify volume driver name (default local)")
 	flags.StringSliceVarP(&volumeCreateCommand.Label, "label", "l", []string{}, "Set metadata for a volume (default [])")
 	flags.StringSliceVarP(&volumeCreateCommand.Opt, "opt", "o", []string{}, "Set driver specific options (default [])")
-
 }
 
 func volumeCreateCmd(c *cliconfig.VolumeCreateValues) error {
diff --git a/libpod/options.go b/libpod/options.go
index 7fbd0016a..3a123a2a6 100644
--- a/libpod/options.go
+++ b/libpod/options.go
@@ -1362,6 +1362,17 @@ func WithNamedVolumes(volumes []*ContainerNamedVolume) CtrCreateOption {
 	}
 }
 
+// WithHealthCheck adds the healthcheck to the container config
+func WithHealthCheck(healthCheck *manifest.Schema2HealthConfig) CtrCreateOption {
+	return func(ctr *Container) error {
+		if ctr.valid {
+			return define.ErrCtrFinalized
+		}
+		ctr.config.HealthCheckConfig = healthCheck
+		return nil
+	}
+}
+
 // Volume Creation Options
 
 // WithVolumeName sets the name of the volume.
@@ -1381,30 +1392,30 @@ func WithVolumeName(name string) VolumeCreateOption {
 	}
 }
 
-// WithVolumeLabels sets the labels of the volume.
-func WithVolumeLabels(labels map[string]string) VolumeCreateOption {
+// WithVolumeDriver sets the volume's driver.
+// It is presently not implemented, but will be supported in a future Podman
+// release.
+func WithVolumeDriver(driver string) VolumeCreateOption {
 	return func(volume *Volume) error {
 		if volume.valid {
 			return define.ErrVolumeFinalized
 		}
 
-		volume.config.Labels = make(map[string]string)
-		for key, value := range labels {
-			volume.config.Labels[key] = value
-		}
-
-		return nil
+		return define.ErrNotImplemented
 	}
 }
 
-// WithVolumeDriver sets the driver of the volume.
-func WithVolumeDriver(driver string) VolumeCreateOption {
+// WithVolumeLabels sets the labels of the volume.
+func WithVolumeLabels(labels map[string]string) VolumeCreateOption {
 	return func(volume *Volume) error {
 		if volume.valid {
 			return define.ErrVolumeFinalized
 		}
 
-		volume.config.Driver = driver
+		volume.config.Labels = make(map[string]string)
+		for key, value := range labels {
+			volume.config.Labels[key] = value
+		}
 
 		return nil
 	}
@@ -1673,14 +1684,3 @@ func WithInfraContainerPorts(bindings []ocicni.PortMapping) PodCreateOption {
 		return nil
 	}
 }
-
-// WithHealthCheck adds the healthcheck to the container config
-func WithHealthCheck(healthCheck *manifest.Schema2HealthConfig) CtrCreateOption {
-	return func(ctr *Container) error {
-		if ctr.valid {
-			return define.ErrCtrFinalized
-		}
-		ctr.config.HealthCheckConfig = healthCheck
-		return nil
-	}
-}
diff --git a/libpod/runtime_volume_linux.go b/libpod/runtime_volume_linux.go
index ac6fd02c3..84703787d 100644
--- a/libpod/runtime_volume_linux.go
+++ b/libpod/runtime_volume_linux.go
@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/containers/libpod/libpod/define"
 	"github.com/containers/libpod/libpod/events"
@@ -42,14 +43,10 @@ func (r *Runtime) newVolume(ctx context.Context, options ...VolumeCreateOption)
 	if volume.config.Name == "" {
 		volume.config.Name = stringid.GenerateNonCryptoID()
 	}
-	// TODO: support for other volume drivers
 	if volume.config.Driver == "" {
 		volume.config.Driver = "local"
 	}
-	// TODO: determine when the scope is global and set it to that
-	if volume.config.Scope == "" {
-		volume.config.Scope = "local"
-	}
+	volume.config.CreatedTime = time.Now()
 
 	// Create the mountpoint of this volume
 	volPathRoot := filepath.Join(r.config.VolumePath, volume.config.Name)
diff --git a/libpod/volume.go b/libpod/volume.go
index 9ed2ff087..bb1e9b6f1 100644
--- a/libpod/volume.go
+++ b/libpod/volume.go
@@ -1,5 +1,9 @@
 package libpod
 
+import (
+	"time"
+)
+
 // Volume is the type used to create named volumes
 // TODO: all volumes should be created using this and the Volume API
 type Volume struct {
@@ -15,10 +19,10 @@ type VolumeConfig struct {
 	Name string `json:"name"`
 
 	Labels        map[string]string `json:"labels"`
-	MountPoint    string            `json:"mountPoint"`
 	Driver        string            `json:"driver"`
+	MountPoint    string            `json:"mountPoint"`
+	CreatedTime   time.Time         `json:"createdAt,omitempty"`
 	Options       map[string]string `json:"options"`
-	Scope         string            `json:"scope"`
 	IsCtrSpecific bool              `json:"ctrSpecific"`
 	UID           int               `json:"uid"`
 	GID           int               `json:"gid"`
@@ -29,6 +33,18 @@ func (v *Volume) Name() string {
 	return v.config.Name
 }
 
+// Driver retrieves the volume's driver.
+func (v *Volume) Driver() string {
+	return v.config.Driver
+}
+
+// Scope retrieves the volume's scope.
+// Libpod does not implement volume scoping, and this is provided solely for
+// Docker compatability. It returns only "local".
+func (v *Volume) Scope() string {
+	return "local"
+}
+
 // Labels returns the volume's labels
 func (v *Volume) Labels() map[string]string {
 	labels := make(map[string]string)
@@ -43,11 +59,6 @@ func (v *Volume) MountPoint() string {
 	return v.config.MountPoint
 }
 
-// Driver returns the volume's driver
-func (v *Volume) Driver() string {
-	return v.config.Driver
-}
-
 // Options return the volume's options
 func (v *Volume) Options() map[string]string {
 	options := make(map[string]string)
@@ -58,14 +69,25 @@ func (v *Volume) Options() map[string]string {
 	return options
 }
 
-// Scope returns the scope of the volume
-func (v *Volume) Scope() string {
-	return v.config.Scope
-}
-
 // IsCtrSpecific returns whether this volume was created specifically for a
 // given container. Images with this set to true will be removed when the
 // container is removed with the Volumes parameter set to true.
 func (v *Volume) IsCtrSpecific() bool {
 	return v.config.IsCtrSpecific
 }
+
+// UID returns the UID the volume will be created as.
+func (v *Volume) UID() int {
+	return v.config.UID
+}
+
+// GID returns the GID the volume will be created as.
+func (v *Volume) GID() int {
+	return v.config.GID
+}
+
+// CreatedTime returns the time the volume was created at. It was not tracked
+// for some time, so older volumes may not contain one.
+func (v *Volume) CreatedTime() time.Time {
+	return v.config.CreatedTime
+}
diff --git a/libpod/volume_inspect.go b/libpod/volume_inspect.go
new file mode 100644
index 000000000..893661a7a
--- /dev/null
+++ b/libpod/volume_inspect.go
@@ -0,0 +1,70 @@
+package libpod
+
+import (
+	"time"
+
+	"github.com/containers/libpod/libpod/define"
+)
+
+// InspectVolumeData is the output of Inspect() on a volume. It is matched to
+// the format of 'docker volume inspect'.
+type InspectVolumeData struct {
+	// Name is the name of the volume.
+	Name string `json:"Name"`
+	// Driver is the driver used to create the volume.
+	// This will be properly implemented in a future version.
+	Driver string `json:"Driver"`
+	// Mountpoint is the path on the host where the volume is mounted.
+	Mountpoint string `json:"Mountpoint"`
+	// CreatedAt is the date and time the volume was created at. This is not
+	// stored for older Libpod volumes; if so, it will be omitted.
+	CreatedAt time.Time `json:"CreatedAt,omitempty"`
+	// Status is presently unused and provided only for Docker compatability.
+	// In the future it will be used to return information on the volume's
+	// current state.
+	Status map[string]string `json:"Status,omitempty"`
+	// Labels includes the volume's configured labels, key:value pairs that
+	// can be passed during volume creation to provide information for third
+	// party tools.
+	Labels map[string]string `json:"Labels"`
+	// Scope is unused and provided solely for Docker compatability. It is
+	// unconditionally set to "local".
+	Scope string `json:"Scope"`
+	// Options is a set of options that were used when creating the volume.
+	// It is presently not used.
+	Options map[string]string `json:"Options"`
+	// UID is the UID that the volume was created with.
+	UID int `json:"UID,omitempty"`
+	// GID is the GID that the volume was created with.
+	GID int `json:"GID,omitempty"`
+	// ContainerSpecific indicates that the volume was created as part of a
+	// specific container, and will be removed when that container is
+	// removed.
+	ContainerSpecific bool `json:"ContainerSpecific,omitempty"`
+}
+
+// Inspect provides detailed information about the configuration of the given
+// volume.
+func (v *Volume) Inspect() (*InspectVolumeData, error) {
+	if !v.valid {
+		return nil, define.ErrVolumeRemoved
+	}
+
+	data := new(InspectVolumeData)
+
+	data.Name = v.config.Name
+	data.Driver = v.config.Driver
+	data.Mountpoint = v.config.MountPoint
+	data.CreatedAt = v.config.CreatedTime
+	data.Labels = make(map[string]string)
+	for k, v := range v.config.Labels {
+		data.Labels[k] = v
+	}
+	data.Scope = v.Scope()
+	data.Options = make(map[string]string)
+	data.UID = v.config.UID
+	data.GID = v.config.GID
+	data.ContainerSpecific = v.config.IsCtrSpecific
+
+	return data, nil
+}
diff --git a/pkg/adapter/runtime_remote.go b/pkg/adapter/runtime_remote.go
index 9fae39df0..92478aa0f 100644
--- a/pkg/adapter/runtime_remote.go
+++ b/pkg/adapter/runtime_remote.go
@@ -661,7 +661,6 @@ func varlinkVolumeToVolume(r *LocalRuntime, volumes []iopodman.Volume) []*Volume
 			MountPoint: v.MountPoint,
 			Driver:     v.Driver,
 			Options:    v.Options,
-			Scope:      v.Scope,
 		}
 		n := remoteVolume{
 			Runtime: r,
diff --git a/pkg/adapter/volumes_remote.go b/pkg/adapter/volumes_remote.go
index beacd943a..58f9ba625 100644
--- a/pkg/adapter/volumes_remote.go
+++ b/pkg/adapter/volumes_remote.go
@@ -29,5 +29,5 @@ func (v *Volume) MountPoint() string {
 
 // Scope returns the scope for an adapter.volume
 func (v *Volume) Scope() string {
-	return v.config.Scope
+	return "local"
 }
diff --git a/pkg/varlinkapi/volumes.go b/pkg/varlinkapi/volumes.go
index 19ba38e7c..6dd86d831 100644
--- a/pkg/varlinkapi/volumes.go
+++ b/pkg/varlinkapi/volumes.go
@@ -68,7 +68,6 @@ func (i *LibpodAPI) GetVolumes(call iopodman.VarlinkCall, args []string, all boo
 			MountPoint: v.MountPoint(),
 			Name:       v.Name(),
 			Options:    v.Options(),
-			Scope:      v.Scope(),
 		}
 		volumes = append(volumes, newVol)
 	}