Implement kpod inspect

kpod inspect allows the user to view low-level information about
containers and images

Signed-off-by: Ryan Cole <rcyoalne@gmail.com>

cmd/kpod/inspect.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"text/template"
+
+	"github.com/pkg/errors"
+	"github.com/urfave/cli"
+)
+
+const (
+	defaultFormat = `Container: {{.Container}}
+ID: {{.ContainerID}}
+`
+	inspectTypeContainer = "container"
+	inspectTypeImage     = "image"
+	inspectAll           = "all"
+)
+
+var (
+	inspectFlags = []cli.Flag{
+		cli.StringFlag{
+			Name:  "type, t",
+			Value: inspectAll,
+			Usage: "Return JSON for specified type, (e.g image, container or task)",
+		},
+		cli.StringFlag{
+			Name:  "format, f",
+			Value: defaultFormat,
+			Usage: "Format the output using the given go template",
+		},
+		cli.BoolFlag{
+			Name:  "size",
+			Usage: "Display total file size if the type is container",
+		},
+	}
+	inspectDescription = "This displays the low-level information on containers and images identified by name or ID. By default, this will render all results in a JSON array. If the container and image have the same name, this will return container JSON for unspecified type."
+	inspectCommand     = cli.Command{
+		Name:        "inspect",
+		Usage:       "Displays the configuration of a container or image",
+		Description: inspectDescription,
+		Flags:       inspectFlags,
+		Action:      inspectCmd,
+		ArgsUsage:   "CONTAINER-OR-IMAGE",
+	}
+)
+
+func inspectCmd(c *cli.Context) error {
+	args := c.Args()
+	if len(args) == 0 {
+		return errors.Errorf("container or image name must be specified: kpod inspect [options [...]] name")
+	}
+	if len(args) > 1 {
+		return errors.Errorf("too many arguments specified")
+	}
+
+	itemType := c.String("type")
+	size := c.Bool("size")
+	format := defaultFormat
+	if c.String("format") != "" {
+		format = c.String("format")
+	}
+
+	switch itemType {
+	case inspectTypeContainer:
+	case inspectTypeImage:
+	case inspectAll:
+	default:
+		return errors.Errorf("the only recognized types are %q, %q, and %q", inspectTypeContainer, inspectTypeImage, inspectAll)
+	}
+
+	t := template.Must(template.New("format").Parse(format))
+
+	name := args[0]
+
+	store, err := getStore(c)
+	if err != nil {
+		return err
+	}
+
+	var data interface{}
+	switch itemType {
+	case inspectTypeContainer:
+		data, err = getContainerData(store, name, size)
+		if err != nil {
+			return errors.Wrapf(err, "error parsing container data")
+		}
+	case inspectTypeImage:
+		data, err = getImageData(store, name)
+		if err != nil {
+			return errors.Wrapf(err, "error parsing image data")
+		}
+	case inspectAll:
+		ctrData, err := getContainerData(store, name, size)
+		if err != nil {
+			imgData, err := getImageData(store, name)
+			if err != nil {
+				return errors.Wrapf(err, "error parsing image data")
+			}
+			data = imgData
+
+		} else {
+			data = ctrData
+		}
+	}
+
+	if c.IsSet("format") {
+		if err = t.Execute(os.Stdout, data); err != nil {
+			return err
+		}
+		fmt.Println()
+		return nil
+	}
+
+	d, err := json.MarshalIndent(data, "", "    ")
+	if err != nil {
+		return errors.Wrapf(err, "error encoding build container as json")
+	}
+	_, err = fmt.Println(string(d))
+	return err
+}