Merge pull request #29914 from tmrts/kubelet-rkt-cri/image-store

Automatic merge from submit-queue

Kubelet rkt CRI ImageService

Contains the ImageService stub and the basic tests for the implementation.

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pkg/kubelet/rktshim/doc.go

@@ -0,0 +1,20 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package rktshim is the package that contains the shim code for rkt to be used
+// as the kubelet container runtime implementation that is integrated using the
+// Container Runtime Interface.
+package rktshim

pkg/kubelet/rktshim/imagestore.go

@@ -0,0 +1,61 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rktshim
+
+import (
+	"errors"
+
+	"k8s.io/kubernetes/pkg/kubelet/container"
+)
+
+// TODO(tmrts): Move these errors to the container API for code re-use.
+var (
+	ErrImageNotFound = errors.New("rktshim: image not found")
+)
+
+var _ container.ImageService = (*ImageStore)(nil)
+
+// ImageStore supports CRUD operations for images.
+type ImageStore struct{}
+
+// TODO(tmrts): fill the image store configuration fields.
+type ImageStoreConfig struct{}
+
+// NewImageStore creates an image storage that allows CRUD operations for images.
+func NewImageStore(ImageStoreConfig) (container.ImageService, error) {
+	return &ImageStore{}, nil
+}
+
+// List lists the images residing in the image store.
+func (*ImageStore) List() ([]container.Image, error) {
+	panic("not implemented")
+}
+
+// Pull pulls an image into the image store and uses the given authentication method.
+func (*ImageStore) Pull(container.ImageSpec, container.AuthConfig, *container.PodSandboxConfig) error {
+	panic("not implemented")
+}
+
+// Remove removes the image from the image store.
+func (*ImageStore) Remove(container.ImageSpec) error {
+	panic("not implemented")
+}
+
+// Status returns the status of the image.
+func (*ImageStore) Status(container.ImageSpec) (container.Image, error) {
+	panic("not implemented")
+}

pkg/kubelet/rktshim/imagestore_test.go

@@ -0,0 +1,205 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rktshim
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"k8s.io/kubernetes/pkg/kubelet/container"
+)
+
+var (
+	emptyImgStoreConfig = ImageStoreConfig{}
+	// TODO(tmrts): fill the pod configuration
+	testPodConfig *container.PodSandboxConfig = nil
+)
+
+type imageTestCase struct {
+	Spec           *container.ImageSpec
+	ExpectedStatus *container.Image
+}
+
+func compareContainerImages(got, expected container.Image) error {
+	if got.ID != expected.ID {
+		return fmt.Errorf("mismatching IDs -> expected %q, got %q", got.ID, expected.ID)
+	}
+
+	if !reflect.DeepEqual(got.RepoTags, expected.RepoTags) {
+		return fmt.Errorf("mismatching RepoTags -> expected %q, got %q", got.ID, expected.ID)
+	}
+
+	if !reflect.DeepEqual(got.RepoDigests, expected.RepoDigests) {
+		return fmt.Errorf("mismatching RepoDigests -> expected %q, got %q", got.ID, expected.ID)
+	}
+
+	if got.Size != expected.Size {
+		return fmt.Errorf("mismatching Sizes -> expected %q, got %q", got.ID, expected.ID)
+	}
+
+	return nil
+}
+
+var testImgSpecs = map[string]imageTestCase{
+	"non-existent-image": {
+		&container.ImageSpec{
+			Image: "XXXX_GIBBERISH_XXXX",
+		},
+		nil,
+	},
+	"busybox": {
+		&container.ImageSpec{
+			Image: "busybox",
+		},
+		&container.Image{
+			ID:          "",
+			RepoTags:    []string{},
+			RepoDigests: []string{},
+			Size:        0,
+		},
+	},
+}
+
+var testAuthConfig = map[string]container.AuthConfig{
+	"no-auth": {},
+}
+
+func testNewImageStore(t *testing.T, cfg ImageStoreConfig) container.ImageService {
+	imgStore, err := NewImageStore(cfg)
+	if err != nil {
+		// TODO(tmrts): Implement stringer for rktshim.ImageStoreConfig for test readability.
+		t.Fatalf("rktshim.NewImageStore(%s) got error %q", cfg, err)
+	}
+
+	return imgStore
+}
+
+func TestPullsImageWithoutAuthentication(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	testImg := "busybox"
+	testImgSpec := *testImgSpecs[testImg].Spec
+
+	if err := imgStore.Pull(testImgSpec, testAuthConfig["no-auth"], testPodConfig); err != nil {
+		t.Fatalf("rktshim.ImageStore.PullImage(%q) got error %q", testImg, err)
+	}
+}
+
+func TestQueriesNonExistentImage(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	// New store shouldn't contain this image
+	testImg := "non-existent-image"
+	testImgSpec := *testImgSpecs[testImg].Spec
+
+	if _, err := imgStore.Status(testImgSpec); err != ErrImageNotFound {
+		t.Errorf("rktshim.ImageStore.Status(%q) expected error %q, got %q", testImg, ErrImageNotFound, err)
+	}
+}
+
+func TestQueriesExistentImage(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	testImg := "busybox"
+	testImgSpec := *testImgSpecs[testImg].Spec
+	expectedStatus := *testImgSpecs[testImg].ExpectedStatus
+
+	imgStatus, err := imgStore.Status(testImgSpec)
+	if err != nil {
+		t.Fatalf("rktshim.ImageStore.Status(%q) got error %q", testImg, err)
+	}
+
+	if err := compareContainerImages(imgStatus, expectedStatus); err != nil {
+		t.Errorf("rktshim.ImageStore.Status(%q) %v", testImg, err)
+	}
+}
+
+func TestRemovesImage(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	testImg := "busybox"
+	testImgSpec := *testImgSpecs[testImg].Spec
+
+	if err := imgStore.Pull(testImgSpec, testAuthConfig["no-auth"], testPodConfig); err != nil {
+		t.Fatalf("rktshim.ImageStore.Pull(%q) got error %q", testImg, err)
+	}
+
+	if _, err := imgStore.Status(testImgSpec); err != nil {
+		t.Fatalf("rktshim.ImageStore.Status(%q) got error %q", testImg, err)
+	}
+
+	if err := imgStore.Remove(testImgSpec); err != nil {
+		t.Fatalf("rktshim.ImageStore.Remove(%q) got error %q", testImg, err)
+	}
+
+	if _, err := imgStore.Status(testImgSpec); err != ErrImageNotFound {
+		t.Fatalf("rktshim.ImageStore.Status(%q) expected error %q, got error %q", testImg, ErrImageNotFound, err)
+	}
+}
+
+func TestRemovesNonExistentImage(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	testImg := "non-existent-image"
+	testImgSpec := *testImgSpecs[testImg].Spec
+
+	if err := imgStore.Remove(testImgSpec); err != ErrImageNotFound {
+		t.Fatalf("rktshim.ImageStore.Remove(%q) expected error %q, got error %q", testImg, ErrImageNotFound, err)
+	}
+}
+
+func TestListsImages(t *testing.T) {
+	t.SkipNow()
+
+	imgStore := testNewImageStore(t, emptyImgStoreConfig)
+
+	busyboxImg := "busybox"
+	busyboxImgSpec := *testImgSpecs[busyboxImg].Spec
+	if err := imgStore.Pull(busyboxImgSpec, testAuthConfig["no-auth"], testPodConfig); err != nil {
+		t.Fatalf("rktshim.ImageStore.Pull(%q) got error %q", busyboxImg, err)
+	}
+
+	alpineImg := "alpine"
+	alpineImgSpec := *testImgSpecs[alpineImg].Spec
+	if err := imgStore.Pull(alpineImgSpec, testAuthConfig["no-auth"], testPodConfig); err != nil {
+		t.Fatalf("rktshim.ImageStore.Pull(%q) got error %q", alpineImg, err)
+	}
+
+	imgs, err := imgStore.List()
+	if err != nil {
+		t.Fatalf("rktshim.ImageStore.List() got error %q", err)
+	}
+
+	for _, img := range imgs {
+		expectedImg := *testImgSpecs[img.ID].ExpectedStatus
+
+		if err := compareContainerImages(img, expectedImg); err != nil {
+			t.Errorf("rktshim.ImageStore.List() for %q, %v", img.ID, err)
+		}
+	}
+}