// digestPathComponents provides a consistent path breakdown for a given
// digest. For a generic digest, it will be as follows:
//
// <algorithm>/<hex digest>
//
// Most importantly, for tarsum, the layout looks like this:
//
// tarsum/<version>/<digest algorithm>/<full digest>
//
// If multilevel is true, the first two bytes of the digest will separate
// groups of digest folder. It will be as follows:
//
// <algorithm>/<first two bytes of digest>/<full digest>
//
func digestPathComponents(dgst digest.Digest, multilevel bool) ([]string, error) {
if err := dgst.Validate(); err != nil {
return nil, err
}
algorithm := blobAlgorithmReplacer.Replace(string(dgst.Algorithm()))
hex := dgst.Hex()
prefix := []string{algorithm}
var suffix []string
if multilevel {
suffix = append(suffix, hex[:2])
}
suffix = append(suffix, hex)
if tsi, err := digest.ParseTarSum(dgst.String()); err == nil {
// We have a tarsum!
version := tsi.Version
if version == "" {
version = "v0"
}
prefix = []string{
"tarsum",
version,
tsi.Algorithm,
}
}
return append(prefix, suffix...), nil
}
// Stat ensures that the digest is a member of the specified repository and
// forwards the descriptor request to the global blob store. If the media type
// differs for the repository, we override it.
func (rsrbds *repositoryScopedRedisBlobDescriptorService) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
if err := dgst.Validate(); err != nil {
return distribution.Descriptor{}, err
}
conn := rsrbds.upstream.pool.Get()
defer conn.Close()
// Check membership to repository first
member, err := redis.Bool(conn.Do("SISMEMBER", rsrbds.repositoryBlobSetKey(rsrbds.repo), dgst))
if err != nil {
return distribution.Descriptor{}, err
}
if !member {
return distribution.Descriptor{}, distribution.ErrBlobUnknown
}
upstream, err := rsrbds.upstream.stat(ctx, conn, dgst)
if err != nil {
return distribution.Descriptor{}, err
}
// We allow a per repository mediatype, let's look it up here.
mediatype, err := redis.String(conn.Do("HGET", rsrbds.blobDescriptorHashKey(dgst), "mediatype"))
if err != nil {
return distribution.Descriptor{}, err
}
if mediatype != "" {
upstream.MediaType = mediatype
}
return upstream, nil
}
// Stat retrieves the descriptor data from the redis hash entry.
func (rbds *redisBlobDescriptorService) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
if err := dgst.Validate(); err != nil {
return distribution.Descriptor{}, err
}
conn := rbds.pool.Get()
defer conn.Close()
return rbds.stat(ctx, conn, dgst)
}
// SetDescriptor sets the descriptor data for the given digest using a redis
// hash. A hash is used here since we may store unrelated fields about a layer
// in the future.
func (rbds *redisBlobDescriptorService) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
if err := dgst.Validate(); err != nil {
return err
}
if err := cache.ValidateDescriptor(desc); err != nil {
return err
}
conn := rbds.pool.Get()
defer conn.Close()
return rbds.setDescriptor(ctx, conn, dgst, desc)
}
func (mbdc *mapBlobDescriptorCache) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
if err := dgst.Validate(); err != nil {
return err
}
if err := cache.ValidateDescriptor(desc); err != nil {
return err
}
mbdc.mu.Lock()
defer mbdc.mu.Unlock()
mbdc.descriptors[dgst] = desc
return nil
}
func (mbdc *mapBlobDescriptorCache) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
if err := dgst.Validate(); err != nil {
return distribution.Descriptor{}, err
}
mbdc.mu.RLock()
defer mbdc.mu.RUnlock()
desc, ok := mbdc.descriptors[dgst]
if !ok {
return distribution.Descriptor{}, distribution.ErrBlobUnknown
}
return desc, nil
}
// MakeImageConfig returns immutable configuration JSON for image based on the
// v1Compatibility object, layer digest and parent StrongID. SHA256() of this
// config is the new image ID (strongID).
func MakeImageConfig(v1Compatibility []byte, layerID, parentID digest.Digest) ([]byte, error) {
// Detect images created after 1.8.3
img, err := NewImgJSON(v1Compatibility)
if err != nil {
return nil, err
}
useFallback := version.Version(img.DockerVersion).LessThan(noFallbackMinVersion)
if useFallback {
// Fallback for pre-1.8.3. Calculate base config based on Image struct
// so that fields with default values added by Docker will use same ID
logrus.Debugf("Using fallback hash for %v", layerID)
v1Compatibility, err = json.Marshal(img)
if err != nil {
return nil, err
}
}
var c map[string]*json.RawMessage
if err := json.Unmarshal(v1Compatibility, &c); err != nil {
return nil, err
}
if err := layerID.Validate(); err != nil {
return nil, fmt.Errorf("invalid layerID: %v", err)
}
c["layer_id"] = rawJSON(layerID)
if parentID != "" {
if err := parentID.Validate(); err != nil {
return nil, fmt.Errorf("invalid parentID %v", err)
}
c["parent_id"] = rawJSON(parentID)
}
delete(c, "id")
delete(c, "parent")
delete(c, "Size") // Size is calculated from data on disk and is inconsitent
return json.Marshal(c)
}
func (rbds *redisBlobDescriptorService) Clear(ctx context.Context, dgst digest.Digest) error {
if err := dgst.Validate(); err != nil {
return err
}
conn := rbds.pool.Get()
defer conn.Close()
// Not atomic in redis <= 2.3
reply, err := conn.Do("HDEL", rbds.blobDescriptorHashKey(dgst), "digest", "length", "mediatype")
if err != nil {
return err
}
if reply == 0 {
return distribution.ErrBlobUnknown
}
return nil
}
func (rsrbds *repositoryScopedRedisBlobDescriptorService) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
if err := dgst.Validate(); err != nil {
return err
}
if err := cache.ValidateDescriptor(desc); err != nil {
return err
}
if dgst != desc.Digest {
if dgst.Algorithm() == desc.Digest.Algorithm() {
return fmt.Errorf("redis cache: digest for descriptors differ but algorthim does not: %q != %q", dgst, desc.Digest)
}
}
conn := rsrbds.upstream.pool.Get()
defer conn.Close()
return rsrbds.setDescriptor(ctx, conn, dgst, desc)
}
// Clear removes the descriptor from the cache and forwards to the upstream descriptor store
func (rsrbds *repositoryScopedRedisBlobDescriptorService) Clear(ctx context.Context, dgst digest.Digest) error {
if err := dgst.Validate(); err != nil {
return err
}
conn := rsrbds.upstream.pool.Get()
defer conn.Close()
// Check membership to repository first
member, err := redis.Bool(conn.Do("SISMEMBER", rsrbds.repositoryBlobSetKey(rsrbds.repo), dgst))
if err != nil {
return err
}
if !member {
return distribution.ErrBlobUnknown
}
return rsrbds.upstream.Clear(ctx, dgst)
}