[#168] object: Implement binary/JSON encoders/decoders on Header

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

v2/object/json.go

@@ -64,3 +64,23 @@ func (h *SplitHeader) UnmarshalJSON(data []byte) error {
 
 	return nil
 }
+
+func (h *Header) MarshalJSON() ([]byte, error) {
+	return protojson.MarshalOptions{
+		EmitUnpopulated: true,
+	}.Marshal(
+		HeaderToGRPCMessage(h),
+	)
+}
+
+func (h *Header) UnmarshalJSON(data []byte) error {
+	msg := new(object.Header)
+
+	if err := protojson.Unmarshal(data, msg); err != nil {
+		return err
+	}
+
+	*h = *HeaderFromGRPCMessage(msg)
+
+	return nil
+}

v2/object/json_test.go

@@ -42,3 +42,15 @@ func TestSplitHeaderJSON(t *testing.T) {
 
 	require.Equal(t, h, h2)
 }
+
+func TestHeaderJSON(t *testing.T) {
+	h := generateHeader(10)
+
+	data, err := h.MarshalJSON()
+	require.NoError(t, err)
+
+	h2 := new(object.Header)
+	require.NoError(t, h2.UnmarshalJSON(data))
+
+	require.Equal(t, h, h2)
+}

v2/object/marshal.go

@@ -422,6 +422,17 @@ func (h *Header) StableSize() (size int) {
 	return size
 }
 
+func (h *Header) Unmarshal(data []byte) error {
+	m := new(object.Header)
+	if err := goproto.Unmarshal(data, m); err != nil {
+		return err
+	}
+
+	*h = *HeaderFromGRPCMessage(m)
+
+	return nil
+}
+
 func (h *HeaderWithSignature) StableMarshal(buf []byte) ([]byte, error) {
 	if h == nil {
 		return []byte{}, nil

v2/object/marshal_test.go

@@ -65,16 +65,13 @@ func TestHeader_StableMarshal(t *testing.T) {
 	from := generateHeader(500)
 	from.SetSplit(split)
 
-	transport := new(grpc.Header)
-
 	t.Run("non empty", func(t *testing.T) {
 		wire, err := from.StableMarshal(nil)
 		require.NoError(t, err)
 
-		err = goproto.Unmarshal(wire, transport)
-		require.NoError(t, err)
+		to := new(object.Header)
+		require.NoError(t, to.Unmarshal(wire))
 
-		to := object.HeaderFromGRPCMessage(transport)
 		require.Equal(t, from, to)
 	})
 }