GMP msg_server implementation

app/app.go

@@ -768,6 +768,7 @@ func New(
 		app.IBCKeeper.ChannelKeeper,
 		app.IBCKeeper.PortKeeper,
 		scopedGmpKeeper,
+		app.TransferKeeper,
 	)
 	gmpModule := gmpmodule.NewAppModule(appCodec, app.GmpKeeper, app.AccountKeeper, app.BankKeeper)
 

proto/ssc/gmp/tx.proto

@@ -2,6 +2,16 @@ syntax = "proto3";
 package ssc.gmp;
 
 option go_package = "github.com/sagaxyz/ssc/x/gmp/types";
+import "cosmos/base/v1beta1/coin.proto";
 
 // Msg defines the Msg service.
-service Msg {}
+service Msg { rpc Transfer(MsgMultiSend) returns (MsgMultiSendResponse); }
+
+message MsgMultiSend {
+  string from_address = 1;
+  string to_address = 2;
+  cosmos.base.v1beta1.Coin amount = 3;
+  string destination_chain = 4;
+}
+
+message MsgMultiSendResponse {}

testutil/keeper/gmp.go

@@ -18,6 +18,7 @@ import (
 	typesparams "github.com/cosmos/cosmos-sdk/x/params/types"
 	capabilitykeeper "github.com/cosmos/ibc-go/modules/capability/keeper"
 	capabilitytypes "github.com/cosmos/ibc-go/modules/capability/types"
+	ibctransferkeeper "github.com/cosmos/ibc-go/v8/modules/apps/transfer/keeper"
 	clienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	"github.com/stretchr/testify/require"
@@ -87,6 +88,7 @@ func GmpKeeper(t testing.TB) (*keeper.Keeper, sdk.Context) {
 		gmpChannelKeeper{},
 		gmpPortKeeper{},
 		capabilityKeeper.ScopeToModule("GmpScopedKeeper"),
+		ibctransferkeeper.Keeper{},
 	)
 
 	ctx := sdk.NewContext(stateStore, tmproto.Header{}, false, logger)

x/gmp/keeper/keeper.go

@@ -1,6 +1,7 @@
 package keeper
 
 import (
+	"context"
 	"fmt"
 
 	cosmossdkerrors "cosmossdk.io/errors"
@@ -10,6 +11,8 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
 	capabilitytypes "github.com/cosmos/ibc-go/modules/capability/types"
+	ibctransferkeeper "github.com/cosmos/ibc-go/v8/modules/apps/transfer/keeper"
+	ibctransfertypes "github.com/cosmos/ibc-go/v8/modules/apps/transfer/types"
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
 	"github.com/cosmos/ibc-go/v8/modules/core/exported"
@@ -27,6 +30,7 @@ type (
 		channelKeeper types.ChannelKeeper
 		portKeeper    types.PortKeeper
 		scopedKeeper  exported.ScopedKeeper
+		ibcKeeper     ibctransferkeeper.Keeper
 	}
 )
 
@@ -38,6 +42,7 @@ func NewKeeper(
 	channelKeeper types.ChannelKeeper,
 	portKeeper types.PortKeeper,
 	scopedKeeper exported.ScopedKeeper,
+	ibcKeeper ibctransferkeeper.Keeper,
 
 ) *Keeper {
 	// set KeyTable if it has not already been set
@@ -54,6 +59,7 @@ func NewKeeper(
 		channelKeeper: channelKeeper,
 		portKeeper:    portKeeper,
 		scopedKeeper:  scopedKeeper,
+		ibcKeeper:     ibcKeeper,
 	}
 }
 
@@ -110,3 +116,13 @@ func (k Keeper) ClaimCapability(ctx sdk.Context, cap *capabilitytypes.Capability
 func (k Keeper) Logger(ctx sdk.Context) log.Logger {
 	return ctx.Logger().With("module", fmt.Sprintf("x/%s", types.ModuleName))
 }
+
+func (k Keeper) Transfer(goCtx context.Context, msg *ibctransfertypes.MsgTransfer) (*types.MsgMultiSendResponse, error) {
+	// TODO: msg.Receiver == AxelarGMPAcc
+
+	_, err := k.ibcKeeper.Transfer(goCtx, msg)
+	if err != nil {
+		return nil, err
+	}
+	return &types.MsgMultiSendResponse{}, nil
+}

x/gmp/keeper/msg_server.go

@@ -1,17 +1,106 @@
 package keeper
 
 import (
+	"context"
+	"encoding/json"
+	"time"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	ibctransfertypes "github.com/cosmos/ibc-go/v8/modules/apps/transfer/types"
+	clienttypes "github.com/cosmos/ibc-go/v8/modules/core/02-client/types"
+	"github.com/ethereum/go-ethereum/accounts/abi"
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/sagaxyz/ssc/x/gmp/types"
 )
 
+// AxelarGMPAcc is the address that receives the message from a cosmos chain
+const AxelarGMPAcc = "axelar1dv4u5k73pzqrxlzujxg3qp8kvc3pje7jtdvu72npnt5zhq05ejcsn5qme5"
+
+type MessageType int
+
+const (
+	// TypeUnrecognized means coin type is unrecognized
+	TypeUnrecognized = iota
+	// TypeGeneralMessage is a pure message
+	TypeGeneralMessage
+	// TypeGeneralMessageWithToken is a general message with token
+	TypeGeneralMessageWithToken
+	// TypeSendToken is a direct token transfer
+	TypeSendToken
+)
+
+// Message is attached in ICS20 packet memo field
+type Message struct {
+	DestinationChain   string `json:"destination_chain"`
+	DestinationAddress string `json:"destination_address"`
+	Payload            []byte `json:"payload"`
+	Type               int64  `json:"type"`
+}
+
 type msgServer struct {
-	Keeper
+	keeper Keeper
 }
 
 // NewMsgServerImpl returns an implementation of the MsgServer interface
 // for the provided Keeper.
 func NewMsgServerImpl(keeper Keeper) types.MsgServer {
-	return &msgServer{Keeper: keeper}
+	return &msgServer{keeper: keeper}
+}
+
+func (k msgServer) Transfer(goCtx context.Context, msg *types.MsgMultiSend) (*types.MsgMultiSendResponse, error) {
+	ctx := sdk.UnwrapSDKContext(goCtx)
+
+	// sender, err := sdk.AccAddressFromBech32(msg.Sender)
+	// if err != nil {
+	// 	return nil, err
+	// }
+
+	// build payload that can be decoded by solidity
+	addressesType, err := abi.NewType("address[]", "address[]", nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var addresses []common.Address
+	addresses = append(addresses, common.HexToAddress(msg.ToAddress))
+	// for _, receiver := range msg.ToAddress {
+	// 	addresses = append(addresses, common.HexToAddress(receiver))
+	// }
+
+	payload, err := abi.Arguments{{Type: addressesType}}.Pack(addresses)
+	if err != nil {
+		return nil, err
+	}
+
+	message := Message{
+		DestinationChain:   msg.DestinationChain,
+		DestinationAddress: msg.ToAddress,
+		Payload:            payload,
+		Type:               TypeGeneralMessageWithToken,
+	}
+
+	bz, err := json.Marshal(&message)
+	if err != nil {
+		return nil, err
+	}
+
+	ibcMessage := ibctransfertypes.NewMsgTransfer(
+		ibctransfertypes.PortID,
+		"channel-17", // hard-coded channel id for demo
+		*msg.Amount,
+		msg.FromAddress,
+		AxelarGMPAcc, // TODO: use config
+		clienttypes.ZeroHeight(),
+		uint64(ctx.BlockTime().Add(6*time.Hour).UnixNano()),
+		string(bz),
+	)
+
+	res, err := k.keeper.Transfer(goCtx, ibcMessage)
+	if err != nil {
+		return nil, err
+	}
+
+	return res, nil
 }
 
 var _ types.MsgServer = msgServer{}

x/gmp/types/expected_keepers.go

@@ -4,6 +4,7 @@ import (
 	context "context"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	ibctransfertypes "github.com/cosmos/ibc-go/v8/modules/apps/transfer/types"
 )
 
 // AccountKeeper defines the expected account keeper used for simulations (noalias)
@@ -17,3 +18,7 @@ type BankKeeper interface {
 	SpendableCoins(ctx context.Context, addr sdk.AccAddress) sdk.Coins
 	// Methods imported from bank should be defined here
 }
+
+type IBCTransferKeeper interface {
+	Transfer(goCtx context.Context, msg *ibctransfertypes.MsgTransfer) (*ibctransfertypes.MsgTransferResponse, error)
+}