// CreateImageConfig constructs the image metadata from layers that compose the image
func CreateImageConfig(images []*ImageWithMeta, manifest *Manifest) error {
if len(images) == 0 {
return nil
}
imageLayer := images[0] // the layer that represents the actual image
image := docker.V1Image{}
rootFS := docker.NewRootFS()
history := make([]docker.History, 0, len(images))
diffIDs := make(map[string]string)
var size int64
// step through layers to get command history and diffID from oldest to newest
for i := len(images) - 1; i >= 0; i-- {
layer := images[i]
if err := json.Unmarshal([]byte(layer.meta), &image); err != nil {
return fmt.Errorf("Failed to unmarshall layer history: %s", err)
}
h := docker.History{
Created: image.Created,
Author: image.Author,
CreatedBy: strings.Join(image.ContainerConfig.Cmd, " "),
Comment: image.Comment,
}
history = append(history, h)
rootFS.DiffIDs = append(rootFS.DiffIDs, dockerLayer.DiffID(layer.diffID))
diffIDs[layer.diffID] = layer.ID
size += layer.size
}
// result is constructed without unused fields
result := docker.Image{
V1Image: docker.V1Image{
Comment: image.Comment,
Created: image.Created,
Container: image.Container,
ContainerConfig: image.ContainerConfig,
DockerVersion: image.DockerVersion,
Author: image.Author,
Config: image.Config,
Architecture: image.Architecture,
OS: image.OS,
},
RootFS: rootFS,
History: history,
}
bytes, err := result.MarshalJSON()
if err != nil {
return fmt.Errorf("Failed to marshall image metadata: %s", err)
}
// calculate image ID
sum := fmt.Sprintf("%x", sha256.Sum256(bytes))
log.Infof("Image ID: sha256:%s", sum)
// prepare metadata
result.V1Image.Parent = image.Parent
result.Size = size
result.V1Image.ID = imageLayer.ID
metaData := metadata.ImageConfig{
V1Image: result.V1Image,
ImageID: sum,
// TODO: this will change when issue 1186 is
// implemented -- only populate the digests when pulled by digest
Digests: []string{manifest.Digest},
Tags: []string{options.tag},
Name: manifest.Name,
DiffIDs: diffIDs,
History: history,
}
blob, err := json.Marshal(metaData)
if err != nil {
return fmt.Errorf("Failed to marshal image metadata: %s", err)
}
// store metadata
imageLayer.meta = string(blob)
return nil
}
// CreateImageConfig constructs the image metadata from layers that compose the image
func (ic *ImageC) CreateImageConfig(images []*ImageWithMeta) (metadata.ImageConfig, error) {
imageLayer := images[0] // the layer that represents the actual image
// if we already have an imageID associated with this layerID, we don't need
// to calculate imageID and can just grab the image config from the cache
id := cache.RepositoryCache().GetImageID(imageLayer.ID)
if image, err := cache.ImageCache().Get(id); err == nil {
return *image, nil
}
manifest := ic.ImageManifest
image := docker.V1Image{}
rootFS := docker.NewRootFS()
history := make([]docker.History, 0, len(images))
diffIDs := make(map[string]string)
var size int64
// step through layers to get command history and diffID from oldest to newest
for i := len(images) - 1; i >= 0; i-- {
layer := images[i]
if err := json.Unmarshal([]byte(layer.Meta), &image); err != nil {
return metadata.ImageConfig{}, fmt.Errorf("Failed to unmarshall layer history: %s", err)
}
h := docker.History{
Created: image.Created,
Author: image.Author,
CreatedBy: strings.Join(image.ContainerConfig.Cmd, " "),
Comment: image.Comment,
}
history = append(history, h)
rootFS.DiffIDs = append(rootFS.DiffIDs, dockerLayer.DiffID(layer.DiffID))
diffIDs[layer.DiffID] = layer.ID
size += layer.Size
}
// result is constructed without unused fields
result := docker.Image{
V1Image: docker.V1Image{
Comment: image.Comment,
Created: image.Created,
Container: image.Container,
ContainerConfig: image.ContainerConfig,
DockerVersion: image.DockerVersion,
Author: image.Author,
Config: image.Config,
Architecture: image.Architecture,
OS: image.OS,
},
RootFS: rootFS,
History: history,
}
bytes, err := result.MarshalJSON()
if err != nil {
return metadata.ImageConfig{}, fmt.Errorf("Failed to marshall image metadata: %s", err)
}
// calculate image ID
sum := fmt.Sprintf("%x", sha256.Sum256(bytes))
log.Infof("Image ID: sha256:%s", sum)
// prepare metadata
result.V1Image.Parent = image.Parent
result.Size = size
result.V1Image.ID = imageLayer.ID
imageConfig := metadata.ImageConfig{
V1Image: result.V1Image,
ImageID: sum,
// TODO: this will change when issue 1186 is
// implemented -- only populate the digests when pulled by digest
Digests: []string{manifest.Digest},
Tags: []string{ic.Tag},
Name: manifest.Name,
DiffIDs: diffIDs,
History: history,
Reference: ic.Reference,
}
return imageConfig, nil
}