feat: add setMetadata

pkg/sif/create.go

@@ -8,6 +8,7 @@
 package sif
 
 import (
+	"encoding"
 	"encoding/binary"
 	"errors"
 	"fmt"
@@ -676,3 +677,41 @@ func (f *FileImage) SetPrimPart(id uint32, opts ...SetOpt) error {
 
 	return nil
 }
+
+// SetMetadata writes the mutated descriptors and returns an error if any.
+func (f *FileImage) SetMetadata(id uint32, md encoding.BinaryMarshaler, opts ...SetOpt) error {
+	so := setOpts{}
+
+	if !f.isDeterministic() {
+		so.t = time.Now()
+	}
+
+	for _, opt := range opts {
+		if err := opt(&so); err != nil {
+			return fmt.Errorf("%w", err)
+		}
+	}
+
+	rd, err := f.getDescriptor(WithID(id))
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	if err := rd.setExtra(md); err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	rd.ModifiedAt = so.t.Unix()
+
+	if err := f.writeDescriptors(); err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	f.h.ModifiedAt = so.t.Unix()
+
+	if err := f.writeHeader(); err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	return nil
+}

pkg/sif/create_test.go

@@ -649,3 +649,84 @@ func TestSetPrimPart(t *testing.T) {
 		})
 	}
 }
+
+func TestSetMetadata(t *testing.T) {
+	tests := []struct {
+		name       string
+		createOpts []CreateOpt
+		id         uint32
+		opts       []SetOpt
+		wantErr    error
+	}{
+		{
+			name: "Deterministic",
+			createOpts: []CreateOpt{
+				OptCreateWithID("de170c43-36ab-44a8-bca9-1ea1a070a274"),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+				OptCreateWithTime(time.Unix(946702800, 0)),
+			},
+			id: 1,
+			opts: []SetOpt{
+				OptSetDeterministic(),
+			},
+		},
+		{
+			name: "WithTime",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+			},
+			id: 1,
+			opts: []SetOpt{
+				OptSetWithTime(time.Unix(946702800, 0)),
+			},
+		},
+		{
+			name: "One",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+			},
+			id: 1,
+		},
+		{
+			name: "Two",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfe, 0xed}),
+				),
+			},
+			id: 2,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var b Buffer
+
+			f, err := CreateContainer(&b, tt.createOpts...)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if got, want := f.SetMetadata(tt.id, newOCIBlobDigest(), tt.opts...), tt.wantErr; !errors.Is(got, want) {
+				t.Errorf("got error %v, want %v", got, want)
+			}
+
+			if err := f.UnloadContainer(); err != nil {
+				t.Error(err)
+			}
+
+			g := goldie.New(t, goldie.WithTestNameForDir(true))
+			g.Assert(t, tt.name, b.Bytes())
+		})
+	}
+}

pkg/sif/descriptor.go

@@ -194,6 +194,12 @@ func (d rawDescriptor) isPartitionOfType(pt PartType) bool {
 	return t == pt
 }
 
+// isDeterministic returns true if the timestamps in d are set to
+// deterministic values.
+func (d rawDescriptor) isDeterministic() bool {
+	return (time.Unix(d.CreatedAt, 0).IsZero() && time.Unix(d.ModifiedAt, 0).IsZero())
+}
+
 // Descriptor represents the SIF descriptor type.
 type Descriptor struct {
 	r io.ReaderAt // Backing storage.