[#276] Merge repo with frostfs-api-go

Signed-off-by: Pavel Pogodaev <p.pogodaev@yadro.com>

api/rpc/message/encoding.go

@@ -0,0 +1,40 @@
+package message
+
+import (
+	"encoding/json"
+)
+
+// GRPCConvertedMessage is an interface
+// of the gRPC message that is used
+// for Message encoding/decoding.
+type GRPCConvertedMessage interface {
+	UnmarshalProtobuf([]byte) error
+}
+
+// Unmarshal decodes m from its Protobuf binary representation
+// via related gRPC message.
+//
+// gm should be tof the same type as the m.ToGRPCMessage() return.
+func Unmarshal(m Message, data []byte, gm GRPCConvertedMessage) error {
+	if err := gm.UnmarshalProtobuf(data); err != nil {
+		return err
+	}
+
+	return m.FromGRPCMessage(gm)
+}
+
+// MarshalJSON encodes m to Protobuf JSON representation.
+func MarshalJSON(m Message) ([]byte, error) {
+	return json.Marshal(m.ToGRPCMessage())
+}
+
+// UnmarshalJSON decodes m from its Protobuf JSON representation
+// via related gRPC message.
+//
+// gm should be tof the same type as the m.ToGRPCMessage() return.
+func UnmarshalJSON(m Message, data []byte, gm any) error {
+	if err := json.Unmarshal(data, gm); err != nil {
+		return err
+	}
+	return m.FromGRPCMessage(gm)
+}

api/rpc/message/message.go

@@ -0,0 +1,43 @@
+package message
+
+import (
+	"fmt"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/rpc/grpc"
+)
+
+// Message represents raw Protobuf message
+// that can be transmitted via several
+// transport protocols.
+type Message interface {
+	// Must return gRPC message that can
+	// be used for gRPC protocol transmission.
+	ToGRPCMessage() grpc.Message
+
+	// Must restore the message from related
+	// gRPC message.
+	//
+	// If gRPC message is not a related one,
+	// ErrUnexpectedMessageType can be returned
+	// to indicate this.
+	FromGRPCMessage(grpc.Message) error
+}
+
+// ErrUnexpectedMessageType is an error that
+// is used to indicate message mismatch.
+type ErrUnexpectedMessageType struct {
+	exp, act any
+}
+
+// NewUnexpectedMessageType initializes an error about message mismatch
+// between act and exp.
+func NewUnexpectedMessageType(act, exp any) ErrUnexpectedMessageType {
+	return ErrUnexpectedMessageType{
+		exp: exp,
+		act: act,
+	}
+}
+
+func (e ErrUnexpectedMessageType) Error() string {
+	return fmt.Sprintf("unexpected message type %T: expected %T", e.act, e.exp)
+}

api/rpc/message/test/message.go

@@ -0,0 +1,126 @@
+package messagetest
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"testing"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/rpc/message"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/util/proto/encoding"
+	"github.com/stretchr/testify/require"
+)
+
+type jsonMessage interface {
+	json.Marshaler
+	json.Unmarshaler
+}
+
+type binaryMessage interface {
+	StableMarshal([]byte) []byte
+	StableSize() int
+	Unmarshal([]byte) error
+}
+
+func TestRPCMessage(t *testing.T, msgGens ...func(empty bool) message.Message) {
+	for _, msgGen := range msgGens {
+		msg := msgGen(false)
+
+		t.Run(fmt.Sprintf("convert_%T", msg), func(t *testing.T) {
+			msg := msgGen(false)
+
+			err := msg.FromGRPCMessage(100)
+
+			require.True(t, errors.As(err, new(message.ErrUnexpectedMessageType)))
+
+			msg2 := msgGen(true)
+
+			err = msg2.FromGRPCMessage(msg.ToGRPCMessage())
+			require.NoError(t, err)
+
+			require.Equal(t, msg, msg2)
+		})
+
+		t.Run("encoding", func(t *testing.T) {
+			if jm, ok := msg.(jsonMessage); ok {
+				t.Run(fmt.Sprintf("JSON_%T", msg), func(t *testing.T) {
+					data, err := jm.MarshalJSON()
+					require.NoError(t, err)
+
+					jm2 := msgGen(true).(jsonMessage)
+					require.NoError(t, jm2.UnmarshalJSON(data))
+
+					require.Equal(t, jm, jm2)
+				})
+			}
+
+			if bm, ok := msg.(binaryMessage); ok {
+				t.Run(fmt.Sprintf("%T.StableSize() does no allocations", bm), func(t *testing.T) {
+					require.Zero(t, testing.AllocsPerRun(1000, func() {
+						_ = bm.StableSize()
+					}))
+				})
+				t.Run(fmt.Sprintf("Binary_%T", msg), func(t *testing.T) {
+					data := bm.StableMarshal(nil)
+
+					bm2 := msgGen(true).(binaryMessage)
+					require.NoError(t, bm2.Unmarshal(data))
+
+					require.Equal(t, bm, bm2)
+				})
+			}
+			t.Run("compatibility", func(t *testing.T) {
+				testCompatibility(t, msgGen)
+			})
+		})
+	}
+}
+
+func testCompatibility(t *testing.T, msgGen func(empty bool) message.Message) {
+	compareBinary := func(t *testing.T, msg message.Message) {
+		am, ok := msg.(binaryMessage)
+		if !ok {
+			t.Skip()
+		}
+
+		a := am.StableMarshal(nil)
+		b := msg.ToGRPCMessage().(encoding.ProtoMarshaler).MarshalProtobuf(nil)
+		if len(a) == 0 {
+			require.Empty(t, b)
+		} else {
+			require.Equal(t, a, b)
+		}
+	}
+	compareJSON := func(t *testing.T, msg message.Message) {
+		am, ok := msg.(jsonMessage)
+		if !ok {
+			t.Skip()
+		}
+
+		a, err := am.MarshalJSON()
+		require.NoError(t, err)
+
+		b, err := json.Marshal(msg.ToGRPCMessage())
+		require.NoError(t, err)
+
+		require.JSONEq(t, string(a), string(b))
+	}
+	t.Run("empty", func(t *testing.T) {
+		msg := msgGen(true)
+		t.Run(fmt.Sprintf("Binary_%T", msg), func(t *testing.T) {
+			compareBinary(t, msg)
+		})
+		t.Run(fmt.Sprintf("JSON_%T", msg), func(t *testing.T) {
+			compareJSON(t, msg)
+		})
+	})
+	t.Run("not empty", func(t *testing.T) {
+		msg := msgGen(false)
+		t.Run(fmt.Sprintf("Binary_%T", msg), func(t *testing.T) {
+			compareBinary(t, msg)
+		})
+		t.Run(fmt.Sprintf("JSON_%T", msg), func(t *testing.T) {
+			compareJSON(t, msg)
+		})
+	})
+}