distribution/manifest/schema1/reference_builder.go
Sebastiaan van Stijn 1d33874951
go.mod: change imports to github.com/distribution/distribution/v3
Go 1.13 and up enforce import paths to be versioned if a project
contains a go.mod and has released v2 or up.

The current v2.x branches (and releases) do not yet have a go.mod,
and therefore are still allowed to be imported with a non-versioned
import path (go modules add a `+incompatible` annotation in that case).

However, now that this project has a `go.mod` file, incompatible
import paths will not be accepted by go modules, and attempting
to use code from this repository will fail.

This patch uses `v3` for the import-paths (not `v2`), because changing
import paths itself is a breaking change, which means that  the
next release should increment the "major" version to comply with
SemVer (as go modules dictate).

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2021-02-08 18:30:46 +01:00

99 lines
2.8 KiB
Go

package schema1
import (
"context"
"errors"
"fmt"
"github.com/distribution/distribution/v3"
"github.com/distribution/distribution/v3/manifest"
"github.com/distribution/distribution/v3/reference"
"github.com/docker/libtrust"
"github.com/opencontainers/go-digest"
)
// 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,
}
}