Merge pull request #1 from mheon/master

Initial checkin

1 files changed, 261 insertions, 0 deletions

diff --git a/libpod/storage.go b/libpod/storage.go
new file mode 100644
index 000000000..f0bf9e9cd
--- /dev/null
+++ b/libpod/storage.go
@@ -0,0 +1,261 @@
+package libpod
+
+import (
+	"encoding/json"
+	"time"
+
+	istorage "github.com/containers/image/storage"
+	"github.com/containers/image/types"
+	"github.com/containers/storage"
+	"github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+type storageService struct {
+	store storage.Store
+}
+
+// getStorageService returns a storageService which can create container root
+// filesystems from images
+func getStorageService(store storage.Store) (*storageService, error) {
+	return &storageService{store: store}, nil
+}
+
+// ContainerInfo wraps a subset of information about a container: the locations
+// of its nonvolatile and volatile per-container directories, along with a copy
+// of the configuration blob from the image that was used to create the
+// container, if the image had a configuration.
+type ContainerInfo struct {
+	Dir    string
+	RunDir string
+	Config *v1.Image
+}
+
+// RuntimeContainerMetadata is the structure that we encode as JSON and store
+// in the metadata field of storage.Container objects.  It is used for
+// specifying attributes containers when they are being created, and allows a
+// container's MountLabel, and possibly other values, to be modified in one
+// read/write cycle via calls to storageService.ContainerMetadata,
+// RuntimeContainerMetadata.SetMountLabel, and
+// storageService.SetContainerMetadata.
+type RuntimeContainerMetadata struct {
+	// The provided name and the ID of the image that was used to
+	// instantiate the container.
+	ImageName string `json:"image-name"` // Applicable to both PodSandboxes and Containers
+	ImageID   string `json:"image-id"`   // Applicable to both PodSandboxes and Containers
+	// The container's name, which for an infrastructure container is usually PodName + "-infra".
+	ContainerName string `json:"name"`                 // Applicable to both PodSandboxes and Containers, mandatory
+	CreatedAt     int64  `json:"created-at"`           // Applicable to both PodSandboxes and Containers
+	MountLabel    string `json:"mountlabel,omitempty"` // Applicable to both PodSandboxes and Containers
+}
+
+// SetMountLabel updates the mount label held by a RuntimeContainerMetadata
+// object.
+func (metadata *RuntimeContainerMetadata) SetMountLabel(mountLabel string) {
+	metadata.MountLabel = mountLabel
+}
+
+// CreateContainerStorage creates the storage end of things.  We already have the container spec created
+// TO-DO We should be passing in an KpodImage object in the future.
+func (r *storageService) CreateContainerStorage(systemContext *types.SystemContext, imageName, imageID, containerName, containerID, mountLabel string) (ContainerInfo, error) {
+	var ref types.ImageReference
+	if imageName == "" && imageID == "" {
+		return ContainerInfo{}, ErrEmptyID
+	}
+	if containerName == "" {
+		return ContainerInfo{}, ErrEmptyID
+	}
+	//// Check if we have the specified image.
+	ref, err := istorage.Transport.ParseStoreReference(r.store, imageName)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	img, err := istorage.Transport.GetStoreImage(r.store, ref)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	// Pull out a copy of the image's configuration.
+	image, err := ref.NewImage(systemContext)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	defer image.Close()
+
+	imageConfig, err := image.OCIConfig()
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+
+	// Update the image name and ID.
+	if imageName == "" && len(img.Names) > 0 {
+		imageName = img.Names[0]
+	}
+	imageID = img.ID
+
+	// Build metadata to store with the container.
+	metadata := RuntimeContainerMetadata{
+		ImageName:     imageName,
+		ImageID:       imageID,
+		ContainerName: containerName,
+		CreatedAt:     time.Now().Unix(),
+		MountLabel:    mountLabel,
+	}
+	mdata, err := json.Marshal(&metadata)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+
+	// Build the container.
+	names := []string{containerName}
+
+	container, err := r.store.CreateContainer(containerID, names, img.ID, "", string(mdata), nil)
+	if err != nil {
+		logrus.Debugf("failed to create container %s(%s): %v", metadata.ContainerName, containerID, err)
+
+		return ContainerInfo{}, err
+	}
+	logrus.Debugf("created container %q", container.ID)
+
+	// If anything fails after this point, we need to delete the incomplete
+	// container before returning.
+	defer func() {
+		if err != nil {
+			if err2 := r.store.DeleteContainer(container.ID); err2 != nil {
+				logrus.Infof("%v deleting partially-created container %q", err2, container.ID)
+
+				return
+			}
+			logrus.Infof("deleted partially-created container %q", container.ID)
+		}
+	}()
+
+	// Add a name to the container's layer so that it's easier to follow
+	// what's going on if we're just looking at the storage-eye view of things.
+	layerName := metadata.ContainerName + "-layer"
+	names, err = r.store.Names(container.LayerID)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	names = append(names, layerName)
+	err = r.store.SetNames(container.LayerID, names)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+
+	// Find out where the container work directories are, so that we can return them.
+	containerDir, err := r.store.ContainerDirectory(container.ID)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	logrus.Debugf("container %q has work directory %q", container.ID, containerDir)
+
+	containerRunDir, err := r.store.ContainerRunDirectory(container.ID)
+	if err != nil {
+		return ContainerInfo{}, err
+	}
+	logrus.Debugf("container %q has run directory %q", container.ID, containerRunDir)
+
+	return ContainerInfo{
+		Dir:    containerDir,
+		RunDir: containerRunDir,
+		Config: imageConfig,
+	}, nil
+}
+
+func (r *storageService) DeleteContainer(idOrName string) error {
+	if idOrName == "" {
+		return ErrEmptyID
+	}
+	container, err := r.store.Container(idOrName)
+	if err != nil {
+		return err
+	}
+	err = r.store.DeleteContainer(container.ID)
+	if err != nil {
+		logrus.Debugf("failed to delete container %q: %v", container.ID, err)
+		return err
+	}
+	return nil
+}
+
+func (r *storageService) SetContainerMetadata(idOrName string, metadata RuntimeContainerMetadata) error {
+	mdata, err := json.Marshal(&metadata)
+	if err != nil {
+		logrus.Debugf("failed to encode metadata for %q: %v", idOrName, err)
+		return err
+	}
+	return r.store.SetMetadata(idOrName, string(mdata))
+}
+
+func (r *storageService) GetContainerMetadata(idOrName string) (RuntimeContainerMetadata, error) {
+	metadata := RuntimeContainerMetadata{}
+	mdata, err := r.store.Metadata(idOrName)
+	if err != nil {
+		return metadata, err
+	}
+	if err = json.Unmarshal([]byte(mdata), &metadata); err != nil {
+		return metadata, err
+	}
+	return metadata, nil
+}
+
+func (r *storageService) StartContainer(idOrName string) (string, error) {
+	container, err := r.store.Container(idOrName)
+	if err != nil {
+		if errors.Cause(err) == storage.ErrContainerUnknown {
+			return "", ErrNoSuchCtr
+		}
+		return "", err
+	}
+	metadata := RuntimeContainerMetadata{}
+	if err = json.Unmarshal([]byte(container.Metadata), &metadata); err != nil {
+		return "", err
+	}
+	mountPoint, err := r.store.Mount(container.ID, metadata.MountLabel)
+	if err != nil {
+		logrus.Debugf("failed to mount container %q: %v", container.ID, err)
+		return "", err
+	}
+	logrus.Debugf("mounted container %q at %q", container.ID, mountPoint)
+	return mountPoint, nil
+}
+
+func (r *storageService) StopContainer(idOrName string) error {
+	if idOrName == "" {
+		return ErrEmptyID
+	}
+	container, err := r.store.Container(idOrName)
+	if err != nil {
+		return err
+	}
+	err = r.store.Unmount(container.ID)
+	if err != nil {
+		logrus.Debugf("failed to unmount container %q: %v", container.ID, err)
+		return err
+	}
+	logrus.Debugf("unmounted container %q", container.ID)
+	return nil
+}
+
+func (r *storageService) GetWorkDir(id string) (string, error) {
+	container, err := r.store.Container(id)
+	if err != nil {
+		if errors.Cause(err) == storage.ErrContainerUnknown {
+			return "", ErrNoSuchCtr
+		}
+		return "", err
+	}
+	return r.store.ContainerDirectory(container.ID)
+}
+
+func (r *storageService) GetRunDir(id string) (string, error) {
+	container, err := r.store.Container(id)
+	if err != nil {
+		if errors.Cause(err) == storage.ErrContainerUnknown {
+			return "", ErrNoSuchCtr
+		}
+		return "", err
+	}
+	return r.store.ContainerRunDirectory(container.ID)
+}