package schema1 import ( "context" "errors" "fmt" "github.com/docker/distribution" "github.com/docker/distribution/manifest" "github.com/docker/distribution/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, } }