Pull sandbox image and apply image config

Signed-off-by: Lantao Liu <lantaol@google.com>
This commit is contained in:
Lantao Liu 2017-05-27 00:32:04 +00:00
parent 60e28a9460
commit eb20601c08
5 changed files with 114 additions and 71 deletions

View File

@ -55,6 +55,9 @@ const (
)
const (
// defaultSandboxImage is the image used by sandbox container.
// TODO(random-liu): [P1] Build schema 2 pause image and use it here.
defaultSandboxImage = "gcr.io/google.com/noogler-kubernetes/pause-amd64:3.0"
// relativeRootfsPath is the rootfs path relative to bundle path.
relativeRootfsPath = "rootfs"
// defaultRuntime is the runtime to use in containerd. We may support
@ -305,31 +308,39 @@ func getRepoDigestAndTag(namedRef reference.Named, digest imagedigest.Digest) (s
return repoDigest, repoTag
}
// localResolve resolves image reference to image id locally. It returns empty string
// without error if the reference doesn't exist.
func (c *criContainerdService) localResolve(ctx context.Context, ref string) (string, error) {
// localResolve resolves image reference locally and returns corresponding image metadata. It returns
// nil without error if the reference doesn't exist.
func (c *criContainerdService) localResolve(ctx context.Context, ref string) (*metadata.ImageMetadata, error) {
_, err := imagedigest.Parse(ref)
if err == nil {
return ref, nil
}
// ref is not image id, try to resolve it locally.
normalized, err := normalizeImageRef(ref)
if err != nil {
return "", fmt.Errorf("invalid image reference %q: %v", ref, err)
}
image, err := c.imageStoreService.Get(ctx, normalized.String())
if err != nil {
if images.IsNotFound(err) {
return "", nil
// ref is not image id, try to resolve it locally.
normalized, err := normalizeImageRef(ref)
if err != nil {
return nil, fmt.Errorf("invalid image reference %q: %v", ref, err)
}
return "", fmt.Errorf("an error occurred when getting image %q from containerd image store: %v",
normalized.String(), err)
image, err := c.imageStoreService.Get(ctx, normalized.String())
if err != nil {
if images.IsNotFound(err) {
return nil, nil
}
return nil, fmt.Errorf("an error occurred when getting image %q from containerd image store: %v",
normalized.String(), err)
}
desc, err := image.Config(ctx, c.contentStoreService)
if err != nil {
return nil, fmt.Errorf("failed to get image config descriptor: %v", err)
}
ref = desc.Digest.String()
}
desc, err := image.Config(ctx, c.contentStoreService)
imageID := ref
meta, err := c.imageMetadataStore.Get(imageID)
if err != nil {
return "", fmt.Errorf("failed to get image config descriptor: %v", err)
if metadata.IsNotExistError(err) {
return nil, nil
}
return nil, fmt.Errorf("failed to get image %q metadata: %v", imageID, err)
}
return desc.Digest.String(), nil
return meta, nil
}
// getUserFromImage gets uid or user name of the image user.
@ -350,3 +361,27 @@ func getUserFromImage(user string) (*int64, string) {
// If user is a numeric uid.
return &uid, ""
}
// ensureImageExists returns corresponding metadata of the image reference, if image is not
// pulled yet, the function will pull the image.
func (c *criContainerdService) ensureImageExists(ctx context.Context, ref string) (*metadata.ImageMetadata, error) {
meta, err := c.localResolve(ctx, ref)
if err != nil {
return nil, fmt.Errorf("failed to resolve image %q: %v", ref, err)
}
if meta != nil {
return meta, nil
}
// Pull image to ensure the image exists
resp, err := c.PullImage(ctx, &runtime.PullImageRequest{Image: &runtime.ImageSpec{Image: ref}})
if err != nil {
return nil, fmt.Errorf("failed to pull image %q: %v", ref, err)
}
imageID := resp.GetImageRef()
meta, err = c.imageMetadataStore.Get(imageID)
if err != nil {
// It's still possible that someone removed the image right after it is pulled.
return nil, fmt.Errorf("failed to get image %q metadata after pulling: %v", imageID, err)
}
return meta, nil
}

View File

@ -41,21 +41,14 @@ func (c *criContainerdService) RemoveImage(ctx context.Context, r *runtime.Remov
glog.V(2).Infof("RemoveImage %q returns successfully", r.GetImage().GetImage())
}
}()
imageID, err := c.localResolve(ctx, r.GetImage().GetImage())
meta, err := c.localResolve(ctx, r.GetImage().GetImage())
if err != nil {
return nil, fmt.Errorf("can not resolve %q locally: %v", r.GetImage().GetImage(), err)
}
if imageID == "" {
if meta == nil {
// return empty without error when image not found.
return &runtime.RemoveImageResponse{}, nil
}
meta, err := c.imageMetadataStore.Get(imageID)
if err != nil {
if metadata.IsNotExistError(err) {
return &runtime.RemoveImageResponse{}, nil
}
return nil, fmt.Errorf("an error occurred when get image %q metadata: %v", imageID, err)
}
// Also include repo digest, because if user pull image with digest,
// there will also be a corresponding repo digest reference.
for _, ref := range append(meta.RepoTags, meta.RepoDigests...) {
@ -65,14 +58,14 @@ func (c *criContainerdService) RemoveImage(ctx context.Context, r *runtime.Remov
if err == nil || images.IsNotFound(err) {
continue
}
return nil, fmt.Errorf("failed to delete image reference %q for image %q: %v", ref, imageID, err)
return nil, fmt.Errorf("failed to delete image reference %q for image %q: %v", ref, meta.ID, err)
}
err = c.imageMetadataStore.Delete(imageID)
err = c.imageMetadataStore.Delete(meta.ID)
if err != nil {
if metadata.IsNotExistError(err) {
return &runtime.RemoveImageResponse{}, nil
}
return nil, fmt.Errorf("an error occurred when delete image %q matadata: %v", imageID, err)
return nil, fmt.Errorf("an error occurred when delete image %q matadata: %v", meta.ID, err)
}
return &runtime.RemoveImageResponse{}, nil
}

View File

@ -22,8 +22,6 @@ import (
"github.com/golang/glog"
"golang.org/x/net/context"
runtime "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1"
"github.com/kubernetes-incubator/cri-containerd/pkg/metadata"
)
// ImageStatus returns the status of the image, returns nil if the image isn't present.
@ -37,23 +35,14 @@ func (c *criContainerdService) ImageStatus(ctx context.Context, r *runtime.Image
r.GetImage().GetImage(), retRes.GetImage())
}
}()
imageID, err := c.localResolve(ctx, r.GetImage().GetImage())
meta, err := c.localResolve(ctx, r.GetImage().GetImage())
if err != nil {
return nil, fmt.Errorf("can not resolve %q locally: %v", r.GetImage().GetImage(), err)
}
if imageID == "" {
if meta == nil {
// return empty without error when image not found.
return &runtime.ImageStatusResponse{}, nil
}
meta, err := c.imageMetadataStore.Get(imageID)
if err != nil {
if metadata.IsNotExistError(err) {
return &runtime.ImageStatusResponse{}, nil
}
return nil, fmt.Errorf("an error occurred during get image %q metadata: %v",
imageID, err)
}
// TODO(random-liu): [P0] Make sure corresponding snapshot exists. What if snapshot
// doesn't exist?
runtimeImage := &runtime.Image{

View File

@ -21,17 +21,18 @@ import (
"fmt"
"io"
"io/ioutil"
"strings"
"time"
"github.com/containerd/containerd/api/services/execution"
rootfsapi "github.com/containerd/containerd/api/services/rootfs"
prototypes "github.com/gogo/protobuf/types"
"github.com/golang/glog"
imagedigest "github.com/opencontainers/go-digest"
imagespec "github.com/opencontainers/image-spec/specs-go/v1"
runtimespec "github.com/opencontainers/runtime-spec/specs-go"
"github.com/opencontainers/runtime-tools/generate"
"golang.org/x/net/context"
"github.com/containerd/containerd/api/services/execution"
"github.com/containerd/containerd/api/types/mount"
runtime "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1"
"github.com/kubernetes-incubator/cri-containerd/pkg/metadata"
@ -81,10 +82,22 @@ func (c *criContainerdService) RunPodSandbox(ctx context.Context, r *runtime.Run
Config: config,
}
// TODO(random-liu): [P0] Ensure pause image snapshot, apply default image config
// and get snapshot mounts.
// Use fixed rootfs path and sleep command.
const rootPath = "/"
// Ensure sandbox container image snapshot.
imageMeta, err := c.ensureImageExists(ctx, c.sandboxImage)
if err != nil {
return nil, fmt.Errorf("failed to get sandbox image %q: %v", defaultSandboxImage, err)
}
prepareResp, err := c.rootfsService.Prepare(ctx, &rootfsapi.PrepareRequest{
Name: id,
// We are sure that ChainID must be a digest.
ChainID: imagedigest.Digest(imageMeta.ChainID),
Readonly: true,
})
if err != nil {
return nil, fmt.Errorf("failed to prepare sandbox rootfs %q: %v", imageMeta.ChainID, err)
}
// TODO(random-liu): [P0] Cleanup snapshot on failure after switching to new rootfs api.
rootfsMounts := prepareResp.Mounts
// Create sandbox container root directory.
// Prepare streaming named pipe.
@ -124,7 +137,10 @@ func (c *criContainerdService) RunPodSandbox(ctx context.Context, r *runtime.Run
}
// Start sandbox container.
spec := c.generateSandboxContainerSpec(id, config)
spec, err := c.generateSandboxContainerSpec(id, config, imageMeta.Config)
if err != nil {
return nil, fmt.Errorf("failed to generate sandbox container spec: %v", err)
}
rawSpec, err := json.Marshal(spec)
if err != nil {
return nil, fmt.Errorf("failed to marshal oci spec %+v: %v", spec, err)
@ -137,16 +153,7 @@ func (c *criContainerdService) RunPodSandbox(ctx context.Context, r *runtime.Run
Value: rawSpec,
},
// TODO(random-liu): [P0] Get rootfs mount from containerd.
Rootfs: []*mount.Mount{
{
Type: "bind",
Source: rootPath,
Options: []string{
"rw",
"rbind",
},
},
},
Rootfs: rootfsMounts,
Runtime: defaultRuntime,
// No stdin for sandbox container.
Stdout: stdout,
@ -205,20 +212,35 @@ func (c *criContainerdService) RunPodSandbox(ctx context.Context, r *runtime.Run
return &runtime.RunPodSandboxResponse{PodSandboxId: id}, nil
}
func (c *criContainerdService) generateSandboxContainerSpec(id string, config *runtime.PodSandboxConfig) *runtimespec.Spec {
// TODO(random-liu): [P0] Get command from image config.
pauseCommand := []string{"sh", "-c", "while true; do sleep 1000000000; done"}
func (c *criContainerdService) generateSandboxContainerSpec(id string, config *runtime.PodSandboxConfig,
imageConfig *imagespec.ImageConfig) (*runtimespec.Spec, error) {
// Creates a spec Generator with the default spec.
// TODO(random-liu): [P1] Compare the default settings with docker and containerd default.
g := generate.New()
// Apply default config from image config.
for _, e := range imageConfig.Env {
kv := strings.Split(e, "=")
if len(kv) != 2 {
return nil, fmt.Errorf("invalid environment variable in image config %+v", imageConfig)
}
g.AddProcessEnv(kv[0], kv[1])
}
if imageConfig.WorkingDir != "" {
g.SetProcessCwd(imageConfig.WorkingDir)
}
if len(imageConfig.Entrypoint) == 0 {
// Pause image must have entrypoint.
return nil, fmt.Errorf("invalid empty entrypoint in image config %+v", imageConfig)
}
// Set process commands.
g.SetProcessArgs(append(imageConfig.Entrypoint, imageConfig.Cmd...))
// Set relative root path.
g.SetRootPath(relativeRootfsPath)
// Set process commands.
g.SetProcessArgs(pauseCommand)
// Make root of sandbox container read-only.
g.SetRootReadonly(true)
@ -276,5 +298,5 @@ func (c *criContainerdService) generateSandboxContainerSpec(id string, config *r
// TODO(random-liu): [P1] Set default sandbox container resource limit.
return g.Spec()
return g.Spec(), nil
}

View File

@ -65,6 +65,9 @@ type criContainerdService struct {
os osinterface.OS
// rootDir is the directory for managing cri-containerd files.
rootDir string
// sandboxImage is the image to use for sandbox container.
// TODO(random-liu): Make this configurable via flag.
sandboxImage string
// sandboxStore stores all sandbox metadata.
sandboxStore metadata.SandboxStore
// imageMetadataStore stores all image metadata.
@ -100,6 +103,7 @@ func NewCRIContainerdService(conn *grpc.ClientConn, rootDir, networkPluginBinDir
c := &criContainerdService{
os: osinterface.RealOS{},
rootDir: rootDir,
sandboxImage: defaultSandboxImage,
sandboxStore: metadata.NewSandboxStore(store.NewMetadataStore()),
containerStore: metadata.NewContainerStore(store.NewMetadataStore()),
imageMetadataStore: metadata.NewImageMetadataStore(store.NewMetadataStore()),