distribution/manifest/schema1/reference_builder.go
Aaron Lehmann 4441333912 Use reference package internally
Most places in the registry were using string types to refer to
repository names. This changes them to use reference.Named, so the type
system can enforce validation of the naming rules.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
2016-01-22 14:47:05 -08:00

98 lines
2.8 KiB
Go

package schema1
import (
"fmt"
"errors"
"github.com/docker/distribution"
"github.com/docker/distribution/context"
"github.com/docker/distribution/digest"
"github.com/docker/distribution/manifest"
"github.com/docker/distribution/reference"
"github.com/docker/libtrust"
)
// referenceManifestBuilder is a type for constructing manifests from schema1
// dependencies.
type referenceManifestBuilder struct {
Manifest
pk libtrust.PrivateKey
}
// NewReferenceManifestBuilder is used to build new manifests for the current
// schema version using schema1 dependencies.
func NewReferenceManifestBuilder(pk libtrust.PrivateKey, ref reference.Named, architecture string) distribution.ManifestBuilder {
tag := ""
if tagged, isTagged := ref.(reference.Tagged); isTagged {
tag = tagged.Tag()
}
return &referenceManifestBuilder{
Manifest: Manifest{
Versioned: manifest.Versioned{
SchemaVersion: 1,
},
Name: ref.Name(),
Tag: tag,
Architecture: architecture,
},
pk: pk,
}
}
func (mb *referenceManifestBuilder) Build(ctx context.Context) (distribution.Manifest, error) {
m := mb.Manifest
if len(m.FSLayers) == 0 {
return nil, errors.New("cannot build manifest with zero layers or history")
}
m.FSLayers = make([]FSLayer, len(mb.Manifest.FSLayers))
m.History = make([]History, len(mb.Manifest.History))
copy(m.FSLayers, mb.Manifest.FSLayers)
copy(m.History, mb.Manifest.History)
return Sign(&m, mb.pk)
}
// AppendReference adds a reference to the current ManifestBuilder
func (mb *referenceManifestBuilder) AppendReference(d distribution.Describable) error {
r, ok := d.(Reference)
if !ok {
return fmt.Errorf("Unable to add non-reference type to v1 builder")
}
// Entries need to be prepended
mb.Manifest.FSLayers = append([]FSLayer{{BlobSum: r.Digest}}, mb.Manifest.FSLayers...)
mb.Manifest.History = append([]History{r.History}, mb.Manifest.History...)
return nil
}
// References returns the current references added to this builder
func (mb *referenceManifestBuilder) References() []distribution.Descriptor {
refs := make([]distribution.Descriptor, len(mb.Manifest.FSLayers))
for i := range mb.Manifest.FSLayers {
layerDigest := mb.Manifest.FSLayers[i].BlobSum
history := mb.Manifest.History[i]
ref := Reference{layerDigest, 0, history}
refs[i] = ref.Descriptor()
}
return refs
}
// Reference describes a manifest v2, schema version 1 dependency.
// An FSLayer associated with a history entry.
type Reference struct {
Digest digest.Digest
Size int64 // if we know it, set it for the descriptor.
History History
}
// Descriptor describes a reference
func (r Reference) Descriptor() distribution.Descriptor {
return distribution.Descriptor{
MediaType: MediaTypeManifestLayer,
Digest: r.Digest,
Size: r.Size,
}
}