[#168] container: Implement binary/JSON encoders/decoders on Container

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

pkg/container/container.go

@@ -111,3 +111,35 @@ func (c *Container) PlacementPolicy() *netmap.PlacementPolicy {
 func (c *Container) SetPlacementPolicy(v *netmap.PlacementPolicy) {
 	c.v2.SetPlacementPolicy(v.ToV2())
 }
+
+// Marshal marshals Container into a protobuf binary form.
+//
+// Buffer is allocated when the argument is empty.
+// Otherwise, the first buffer is used.
+func (c *Container) Marshal(b ...[]byte) ([]byte, error) {
+	var buf []byte
+	if len(b) > 0 {
+		buf = b[0]
+	}
+
+	return c.v2.
+		StableMarshal(buf)
+}
+
+// Unmarshal unmarshals protobuf binary representation of Container.
+func (c *Container) Unmarshal(data []byte) error {
+	return c.v2.
+		Unmarshal(data)
+}
+
+// MarshalJSON encodes Container to protobuf JSON format.
+func (c *Container) MarshalJSON() ([]byte, error) {
+	return c.v2.
+		MarshalJSON()
+}
+
+// UnmarshalJSON decodes Container from protobuf JSON format.
+func (c *Container) UnmarshalJSON(data []byte) error {
+	return c.v2.
+		UnmarshalJSON(data)
+}

pkg/container/container_test.go

@@ -66,3 +66,29 @@ func generatePlacementPolicy() *netmap.PlacementPolicy {
 
 	return p
 }
+
+func TestContainerEncoding(t *testing.T) {
+	c := container.New(
+		container.WithAttribute("key", "value"),
+	)
+
+	t.Run("binary", func(t *testing.T) {
+		data, err := c.Marshal()
+		require.NoError(t, err)
+
+		c2 := container.New()
+		require.NoError(t, c2.Unmarshal(data))
+
+		require.Equal(t, c, c2)
+	})
+
+	t.Run("json", func(t *testing.T) {
+		data, err := c.MarshalJSON()
+		require.NoError(t, err)
+
+		c2 := container.New()
+		require.NoError(t, c2.UnmarshalJSON(data))
+
+		require.Equal(t, c, c2)
+	})
+}

v2/container/json.go

@@ -1,40 +1,10 @@
 package container
 
 import (
-	"errors"
-
 	container "github.com/nspcc-dev/neofs-api-go/v2/container/grpc"
 	"google.golang.org/protobuf/encoding/protojson"
 )
 
-var (
-	errEmptyInput = errors.New("empty input")
-)
-
-func ContainerToJSON(c *Container) ([]byte, error) {
-	if c == nil {
-		return nil, errEmptyInput
-	}
-
-	msg := ContainerToGRPCMessage(c)
-
-	return protojson.MarshalOptions{EmitUnpopulated: true}.Marshal(msg)
-}
-
-func ContainerFromJSON(data []byte) (*Container, error) {
-	if len(data) == 0 {
-		return nil, errEmptyInput
-	}
-
-	msg := new(container.Container)
-
-	if err := protojson.Unmarshal(data, msg); err != nil {
-		return nil, err
-	}
-
-	return ContainerFromGRPCMessage(msg), nil
-}
-
 func (a *Attribute) MarshalJSON() ([]byte, error) {
 	return protojson.MarshalOptions{
 		EmitUnpopulated: true,
@@ -54,3 +24,23 @@ func (a *Attribute) UnmarshalJSON(data []byte) error {
 
 	return nil
 }
+
+func (c *Container) MarshalJSON() ([]byte, error) {
+	return protojson.MarshalOptions{
+		EmitUnpopulated: true,
+	}.Marshal(
+		ContainerToGRPCMessage(c),
+	)
+}
+
+func (c *Container) UnmarshalJSON(data []byte) error {
+	msg := new(container.Container)
+
+	if err := protojson.Unmarshal(data, msg); err != nil {
+		return err
+	}
+
+	*c = *ContainerFromGRPCMessage(msg)
+
+	return nil
+}

v2/container/json_test.go

@@ -8,25 +8,15 @@ import (
 )
 
 func TestContainerJSON(t *testing.T) {
-	exp := generateContainer("container")
+	c := generateContainer("nonce")
 
-	t.Run("non empty", func(t *testing.T) {
-		data, err := container.ContainerToJSON(exp)
-		require.NoError(t, err)
+	data, err := c.MarshalJSON()
+	require.NoError(t, err)
 
-		got, err := container.ContainerFromJSON(data)
-		require.NoError(t, err)
+	c2 := new(container.Container)
+	require.NoError(t, c2.UnmarshalJSON(data))
 
-		require.Equal(t, exp, got)
-	})
-
-	t.Run("empty", func(t *testing.T) {
-		_, err := container.ContainerToJSON(nil)
-		require.Error(t, err)
-
-		_, err = container.ContainerFromJSON(nil)
-		require.Error(t, err)
-	})
+	require.Equal(t, c, c2)
 }
 
 func TestAttributeJSON(t *testing.T) {

v2/container/marshal.go

@@ -171,6 +171,17 @@ func (c *Container) StableSize() (size int) {
 	return size
 }
 
+func (c *Container) Unmarshal(data []byte) error {
+	m := new(container.Container)
+	if err := proto.Unmarshal(data, m); err != nil {
+		return err
+	}
+
+	*c = *ContainerFromGRPCMessage(m)
+
+	return nil
+}
+
 func (r *PutRequestBody) StableMarshal(buf []byte) ([]byte, error) {
 	if r == nil {
 		return []byte{}, nil

v2/container/marshal_test.go

@@ -28,16 +28,14 @@ func TestAttribute_StableMarshal(t *testing.T) {
 
 func TestContainer_StableMarshal(t *testing.T) {
 	cnrFrom := generateContainer("nonce")
-	transport := new(grpc.Container)
 
 	t.Run("non empty", func(t *testing.T) {
 		wire, err := cnrFrom.StableMarshal(nil)
 		require.NoError(t, err)
 
-		err = goproto.Unmarshal(wire, transport)
-		require.NoError(t, err)
+		cnrTo := new(container.Container)
+		require.NoError(t, cnrTo.Unmarshal(wire))
 
-		cnrTo := container.ContainerFromGRPCMessage(transport)
 		require.Equal(t, cnrFrom, cnrTo)
 	})
 }