[#168] refs: Implement binary/JSON encoders/decoders on Signature

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/signature.go

@@ -42,3 +42,35 @@ func (s *Signature) SetSign(v []byte) {
 func (s *Signature) ToV2() *refs.Signature {
 	return (*refs.Signature)(s)
 }
+
+// Marshal marshals Signature into a protobuf binary form.
+//
+// Buffer is allocated when the argument is empty.
+// Otherwise, the first buffer is used.
+func (s *Signature) Marshal(b ...[]byte) ([]byte, error) {
+	var buf []byte
+	if len(b) > 0 {
+		buf = b[0]
+	}
+
+	return (*refs.Signature)(s).
+		StableMarshal(buf)
+}
+
+// Unmarshal unmarshals protobuf binary representation of Signature.
+func (s *Signature) Unmarshal(data []byte) error {
+	return (*refs.Signature)(s).
+		Unmarshal(data)
+}
+
+// MarshalJSON encodes Signature to protobuf JSON format.
+func (s *Signature) MarshalJSON() ([]byte, error) {
+	return (*refs.Signature)(s).
+		MarshalJSON()
+}
+
+// UnmarshalJSON decodes Signature from protobuf JSON format.
+func (s *Signature) UnmarshalJSON(data []byte) error {
+	return (*refs.Signature)(s).
+		UnmarshalJSON(data)
+}

pkg/signature_test.go

@@ -0,0 +1,33 @@
+package pkg
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestSignatureEncoding(t *testing.T) {
+	s := NewSignature()
+	s.SetKey([]byte("key"))
+	s.SetSign([]byte("sign"))
+
+	t.Run("binary", func(t *testing.T) {
+		data, err := s.Marshal()
+		require.NoError(t, err)
+
+		s2 := NewSignature()
+		require.NoError(t, s2.Unmarshal(data))
+
+		require.Equal(t, s, s2)
+	})
+
+	t.Run("json", func(t *testing.T) {
+		data, err := s.MarshalJSON()
+		require.NoError(t, err)
+
+		s2 := NewSignature()
+		require.NoError(t, s2.UnmarshalJSON(data))
+
+		require.Equal(t, s, s2)
+	})
+}