pkg/kubelet/rktshim: implement ImageStore

pkg/kubelet/rktshim/imagestore.go

@@ -18,8 +18,14 @@ package rktshim
 
 import (
 	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
 
 	runtimeApi "k8s.io/kubernetes/pkg/kubelet/api/v1alpha1/runtime"
+
+	"k8s.io/kubernetes/pkg/kubelet/container"
 )
 
 // TODO(tmrts): Move these errors to the container API for code re-use.
@@ -30,32 +36,87 @@ var (
 // var _ kubeletApi.ImageManagerService = (*ImageStore)(nil)
 
 // ImageStore supports CRUD operations for images.
-type ImageStore struct{}
+type ImageStore struct {
+	rkt            CLI
+	requestTimeout time.Duration
+}
 
 // TODO(tmrts): fill the image store configuration fields.
-type ImageStoreConfig struct{}
+type ImageStoreConfig struct {
+	CLI            CLI
+	RequestTimeout time.Duration
+}
 
 // NewImageStore creates an image storage that allows CRUD operations for images.
-func NewImageStore(ImageStoreConfig) (*ImageStore, error) {
-	return &ImageStore{}, nil
+func NewImageStore(cfg ImageStoreConfig) (*ImageStore, error) {
+	return &ImageStore{rkt: cfg.CLI, requestTimeout: cfg.RequestTimeout}, nil
 }
 
 // List lists the images residing in the image store.
-func (*ImageStore) List() ([]runtimeApi.Image, error) {
-	panic("not implemented")
+func (s *ImageStore) List() ([]container.Image, error) {
+	list, err := s.rkt.RunCommand("image", "list",
+		"--no-legend",
+		"--fields=id,name,size",
+		"--sort=importtime",
+	)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't list images: %v", err)
+	}
+
+	images := make([]container.Image, len(list))
+	for i, image := range list {
+		tokens := strings.Fields(image)
+
+		id, name := tokens[0], tokens[1]
+
+		size, err := strconv.ParseInt(tokens[2], 10, 0)
+		if err != nil {
+			return nil, fmt.Errorf("invalid image size format: %v", err)
+		}
+
+		images[i] = container.Image{
+			ID:       id,
+			RepoTags: []string{name},
+			Size:     size,
+		}
+	}
+
+	return images, nil
 }
 
 // Pull pulls an image into the image store and uses the given authentication method.
-func (*ImageStore) Pull(runtimeApi.ImageSpec, runtimeApi.AuthConfig, *runtimeApi.PodSandboxConfig) error {
-	panic("not implemented")
+func (s *ImageStore) Pull(container.ImageSpec, runtimeApi.AuthConfig, *runtimeApi.PodSandboxConfig) error {
+	panic("not implemented yet!")
 }
 
 // Remove removes the image from the image store.
-func (*ImageStore) Remove(runtimeApi.ImageSpec) error {
-	panic("not implemented")
+func (s *ImageStore) Remove(imgSpec container.ImageSpec) error {
+	img, err := s.Status(imgSpec)
+	if err != nil {
+		return err
+	}
+
+	if _, err := s.rkt.RunCommand("image", "rm", img.ID); err != nil {
+		return fmt.Errorf("failed to remove the image: %v", err)
+	}
+
+	return nil
 }
 
 // Status returns the status of the image.
-func (*ImageStore) Status(runtimeApi.ImageSpec) (runtimeApi.Image, error) {
-	panic("not implemented")
+func (s *ImageStore) Status(spec container.ImageSpec) (container.Image, error) {
+	images, err := s.List()
+	if err != nil {
+		return container.Image{}, err
+	}
+
+	for _, img := range images {
+		for _, tag := range img.RepoTags {
+			if tag == spec.Image {
+				return img, nil
+			}
+		}
+	}
+
+	return container.Image{}, fmt.Errorf("couldn't to find the image %v", spec.Image)
 }