imp: Use json for marshalling/unmarshalling transfer packet data. (co…

…smos#5778)

modules/apps/callbacks/ibc_middleware_test.go

@@ -1,6 +1,7 @@
 package ibccallbacks_test
 
 import (
+	"encoding/json"
 	"fmt"
 
 	errorsmod "cosmossdk.io/errors"
@@ -477,7 +478,7 @@ func (s *CallbacksTestSuite) TestOnTimeoutPacket() {
 			s.Require().NoError(err)
 			s.Require().NotNil(packet)
 
-			err = transfertypes.ModuleCdc.UnmarshalJSON(packet.Data, &packetData)
+			err = json.Unmarshal(packet.Data, &packetData)
 			s.Require().NoError(err)
 
 			ctx = s.chainA.GetContext()

modules/apps/transfer/ibc_module.go

@@ -1,6 +1,7 @@
 package transfer
 
 import (
+	"encoding/json"
 	"fmt"
 	"math"
 	"strings"
@@ -182,7 +183,7 @@ func (im IBCModule) OnRecvPacket(
 
 	var data types.FungibleTokenPacketData
 	var ackErr error
-	if err := types.ModuleCdc.UnmarshalJSON(packet.GetData(), &data); err != nil {
+	if err := json.Unmarshal(packet.GetData(), &data); err != nil {
 		ackErr = errorsmod.Wrapf(ibcerrors.ErrInvalidType, "cannot unmarshal ICS-20 transfer packet data")
 		logger.Error(fmt.Sprintf("%s sequence %d", ackErr.Error(), packet.Sequence))
 		ack = channeltypes.NewErrorAcknowledgement(ackErr)
@@ -238,7 +239,7 @@ func (im IBCModule) OnAcknowledgementPacket(
 		return errorsmod.Wrapf(ibcerrors.ErrUnknownRequest, "cannot unmarshal ICS-20 transfer packet acknowledgement: %v", err)
 	}
 	var data types.FungibleTokenPacketData
-	if err := types.ModuleCdc.UnmarshalJSON(packet.GetData(), &data); err != nil {
+	if err := json.Unmarshal(packet.GetData(), &data); err != nil {
 		return errorsmod.Wrapf(ibcerrors.ErrUnknownRequest, "cannot unmarshal ICS-20 transfer packet data: %s", err.Error())
 	}
 
@@ -286,7 +287,7 @@ func (im IBCModule) OnTimeoutPacket(
 	relayer sdk.AccAddress,
 ) error {
 	var data types.FungibleTokenPacketData
-	if err := types.ModuleCdc.UnmarshalJSON(packet.GetData(), &data); err != nil {
+	if err := json.Unmarshal(packet.GetData(), &data); err != nil {
 		return errorsmod.Wrapf(ibcerrors.ErrUnknownRequest, "cannot unmarshal ICS-20 transfer packet data: %s", err.Error())
 	}
 	// refund tokens
@@ -352,7 +353,7 @@ func (IBCModule) OnChanUpgradeOpen(ctx sdk.Context, portID, channelID string, pr
 // PacketDataUnmarshaler interface required for ADR 008 support.
 func (IBCModule) UnmarshalPacketData(bz []byte) (interface{}, error) {
 	var packetData types.FungibleTokenPacketData
-	if err := types.ModuleCdc.UnmarshalJSON(bz, &packetData); err != nil {
+	if err := json.Unmarshal(bz, &packetData); err != nil {
 		return nil, err
 	}
 

modules/apps/transfer/types/codec.go

@@ -1,11 +1,6 @@
 package types
 
 import (
-	"bytes"
-
-	"github.com/cosmos/gogoproto/jsonpb"
-	"github.com/cosmos/gogoproto/proto"
-
 	"github.com/cosmos/cosmos-sdk/codec"
 	"github.com/cosmos/cosmos-sdk/codec/legacy"
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
@@ -39,32 +34,3 @@ func RegisterInterfaces(registry codectypes.InterfaceRegistry) {
 // The actual codec used for serialization should be provided to x/ibc transfer and
 // defined at the application level.
 var ModuleCdc = codec.NewProtoCodec(codectypes.NewInterfaceRegistry())
-
-// mustProtoMarshalJSON provides an auxiliary function to return Proto3 JSON encoded
-// bytes of a message.
-// NOTE: Copied from https://github.com/cosmos/cosmos-sdk/blob/971c542453e0972ef1dfc5a80159ad5049c7211c/codec/json.go
-// and modified in order to allow `EmitDefaults` to be set to false for ics20 packet marshalling.
-// This allows for the introduction of the memo field to be backwards compatible.
-func mustProtoMarshalJSON(msg proto.Message) []byte {
-	anyResolver := codectypes.NewInterfaceRegistry()
-
-	// EmitDefaults is set to false to prevent marshalling of unpopulated fields (memo)
-	// OrigName and the anyResovler match the fields the original SDK function would expect
-	// in order to minimize changes.
-
-	// OrigName is true since there is no particular reason to use camel case
-	// The any resolver is empty, but provided anyways.
-	jm := &jsonpb.Marshaler{OrigName: true, EmitDefaults: false, AnyResolver: anyResolver}
-
-	err := codectypes.UnpackInterfaces(msg, codectypes.ProtoJSONPacker{JSONPBMarshaler: jm})
-	if err != nil {
-		panic(err)
-	}
-
-	buf := new(bytes.Buffer)
-	if err := jm.Marshal(buf, msg); err != nil {
-		panic(err)
-	}
-
-	return buf.Bytes()
-}

modules/apps/transfer/types/packet.go

@@ -2,14 +2,13 @@ package types
 
 import (
 	"encoding/json"
+	"errors"
 	"strings"
 	"time"
 
 	errorsmod "cosmossdk.io/errors"
 	sdkmath "cosmossdk.io/math"
 
-	sdk "github.com/cosmos/cosmos-sdk/types"
-
 	ibcerrors "github.com/cosmos/ibc-go/v8/modules/core/errors"
 	ibcexported "github.com/cosmos/ibc-go/v8/modules/core/exported"
 )
@@ -67,9 +66,16 @@ func (ftpd FungibleTokenPacketData) ValidateBasic() error {
 	return ValidatePrefixedDenom(ftpd.Denom)
 }
 
-// GetBytes is a helper for serialising
+// GetBytes is a helper for serialising the packet to bytes.
+// The memo field of FungibleTokenPacketData is marked with the JSON omitempty tag
+// ensuring that the memo field is not included in the marshalled bytes if one is not specified.
 func (ftpd FungibleTokenPacketData) GetBytes() []byte {
-	return sdk.MustSortJSON(mustProtoMarshalJSON(&ftpd))
+	bz, err := json.Marshal(ftpd)
+	if err != nil {
+		panic(errors.New("cannot marshal FungibleTokenPacketData into bytes"))
+	}
+
+	return bz
 }
 
 // GetPacketSender returns the sender address embedded in the packet data.

modules/apps/transfer/types/packet_test.go

@@ -1,6 +1,7 @@
 package types_test
 
 import (
+	"encoding/json"
 	"fmt"
 	"testing"
 
@@ -134,3 +135,27 @@ func (suite *TypesTestSuite) TestPacketDataProvider() {
 		suite.Require().Equal(tc.expCustomData, customData)
 	}
 }
+
+func (suite *TypesTestSuite) TestFungibleTokenPacketDataOmitEmpty() {
+	// check that omitempty is present for the memo field
+	packetData := types.FungibleTokenPacketData{
+		Denom:    denom,
+		Amount:   amount,
+		Sender:   sender,
+		Receiver: receiver,
+		// Default value for non-specified memo field is empty string
+	}
+
+	bz, err := json.Marshal(packetData)
+	suite.Require().NoError(err)
+
+	// check that the memo field is not present in the marshalled bytes
+	suite.Require().NotContains(string(bz), "memo")
+
+	packetData.Memo = "abc"
+	bz, err = json.Marshal(packetData)
+	suite.Require().NoError(err)
+
+	// check that the memo field is present in the marshalled bytes
+	suite.Require().Contains(string(bz), "memo")
+}