feat: add SetOCIBlobDigest

pkg/sif/descriptor.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2018-2023, Sylabs Inc. All rights reserved.
+// Copyright (c) 2018-2024, Sylabs Inc. All rights reserved.
 // Copyright (c) 2017, SingularityWare, LLC. All rights reserved.
 // Copyright (c) 2017, Yannick Cote <[email protected]> All rights reserved.
 // This software is licensed under a 3-clause BSD license. Please consult the
@@ -92,7 +92,9 @@ func newOCIBlobDigest() *ociBlob {
 
 // MarshalBinary encodes ob into binary format.
 func (ob *ociBlob) MarshalBinary() ([]byte, error) {
-	ob.digest.Hex = hex.EncodeToString(ob.hasher.Sum(nil))
+	if ob.digest.Hex == "" {
+		ob.digest.Hex = hex.EncodeToString(ob.hasher.Sum(nil))
+	}
 
 	return ob.digest.MarshalText()
 }

pkg/sif/set.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2018-2023, Sylabs Inc. All rights reserved.
+// Copyright (c) 2018-2024, Sylabs Inc. All rights reserved.
 // Copyright (c) 2017, SingularityWare, LLC. All rights reserved.
 // Copyright (c) 2017, Yannick Cote <[email protected]> All rights reserved.
 // This software is licensed under a 3-clause BSD license. Please consult the
@@ -12,6 +12,8 @@ import (
 	"errors"
 	"fmt"
 	"time"
+
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 )
 
 // setOpts accumulates object set options.
@@ -167,3 +169,52 @@ func (f *FileImage) SetMetadata(id uint32, md encoding.BinaryMarshaler, opts ...
 
 	return nil
 }
+
+// SetOCIBlobDigest updates the digest of the OCI blob object with id to h, according to opts.
+//
+// By default, the image/object modification times are set to the current time for
+// non-deterministic images, and unset otherwise. To override this, consider using
+// OptSetDeterministic or OptSetWithTime.
+func (f *FileImage) SetOCIBlobDigest(id uint32, h v1.Hash, opts ...SetOpt) error {
+	rd, err := f.getDescriptor(WithID(id))
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	if got := rd.DataType; got != DataOCIRootIndex && got != DataOCIBlob {
+		return &unexpectedDataTypeError{got, []DataType{DataOCIRootIndex, DataOCIBlob}}
+	}
+
+	so := setOpts{}
+
+	if !f.isDeterministic() {
+		so.t = time.Now()
+	}
+
+	for _, opt := range opts {
+		if err := opt(&so); err != nil {
+			return fmt.Errorf("%w", err)
+		}
+	}
+
+	md := &ociBlob{
+		digest: h,
+	}
+	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/set_test.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2018-2023, Sylabs Inc. All rights reserved.
+// Copyright (c) 2018-2024, Sylabs Inc. All rights reserved.
 // This software is licensed under a 3-clause BSD license. Please consult the
 // LICENSE file distributed with the sources of this project regarding your
 // rights to use or distribute this software.
@@ -10,6 +10,7 @@ import (
 	"testing"
 	"time"
 
+	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/sebdah/goldie/v2"
 )
 
@@ -195,3 +196,118 @@ func TestSetMetadata(t *testing.T) {
 		})
 	}
 }
+
+func TestFileImage_SetOCIBlobDigest(t *testing.T) {
+	tests := []struct {
+		name       string
+		createOpts []CreateOpt
+		id         uint32
+		h          v1.Hash
+		opts       []SetOpt
+		wantErr    error
+	}{
+		{
+			name: "UnexpectedDataType",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataGeneric, []byte{0xfa, 0xce}),
+				),
+			},
+			id: 1,
+			h: v1.Hash{
+				Algorithm: "sha256",
+				Hex:       "93a6ab73f77ce27501f74bb35af9b4da5b964c62f96175a1bc0e8ba2ae0dec08",
+			},
+			wantErr: &unexpectedDataTypeError{DataGeneric, []DataType{DataOCIBlob, DataOCIRootIndex}},
+		},
+		{
+			name: "Deterministic",
+			createOpts: []CreateOpt{
+				OptCreateWithID("de170c43-36ab-44a8-bca9-1ea1a070a274"),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+				OptCreateWithTime(time.Unix(946702800, 0)),
+			},
+			id: 1,
+			h: v1.Hash{
+				Algorithm: "sha256",
+				Hex:       "93a6ab73f77ce27501f74bb35af9b4da5b964c62f96175a1bc0e8ba2ae0dec08",
+			},
+			opts: []SetOpt{
+				OptSetDeterministic(),
+			},
+		},
+		{
+			name: "WithTime",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+			},
+			id: 1,
+			h: v1.Hash{
+				Algorithm: "sha256",
+				Hex:       "93a6ab73f77ce27501f74bb35af9b4da5b964c62f96175a1bc0e8ba2ae0dec08",
+			},
+			opts: []SetOpt{
+				OptSetWithTime(time.Unix(946702800, 0)),
+			},
+		},
+		{
+			name: "One",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+				),
+			},
+			id: 1,
+			h: v1.Hash{
+				Algorithm: "sha256",
+				Hex:       "93a6ab73f77ce27501f74bb35af9b4da5b964c62f96175a1bc0e8ba2ae0dec08",
+			},
+		},
+		{
+			name: "Two",
+			createOpts: []CreateOpt{
+				OptCreateDeterministic(),
+				OptCreateWithDescriptors(
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfa, 0xce}),
+					getDescriptorInput(t, DataOCIBlob, []byte{0xfe, 0xed}),
+				),
+			},
+			id: 2,
+			h: v1.Hash{
+				Algorithm: "sha256",
+				Hex:       "93a6ab73f77ce27501f74bb35af9b4da5b964c62f96175a1bc0e8ba2ae0dec08",
+			},
+		},
+	}
+
+	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.SetOCIBlobDigest(tt.id, tt.h, 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)
+			}
+
+			if tt.wantErr == nil {
+				g := goldie.New(t, goldie.WithTestNameForDir(true))
+				g.Assert(t, tt.name, b.Bytes())
+			}
+		})
+	}
+}