refactor: emit cumulative fees when incentivizing a packet multiple t…

…imes (cosmos#1391)

* emit cumulative fees

* test: add test for emission of cumulative incentivized fees

* add check for nil relayer

* reassign sdk.Coins, fix bug

modules/apps/29-fee/keeper/escrow.go

@@ -39,7 +39,7 @@ func (k Keeper) escrowPacketFee(ctx sdk.Context, packetID channeltypes.PacketId,
 	packetFees := types.NewPacketFees(fees)
 	k.SetFeesInEscrow(ctx, packetID, packetFees)
 
-	EmitIncentivizedPacket(ctx, packetID, packetFee)
+	EmitIncentivizedPacketEvent(ctx, packetID, packetFees)
 
 	return nil
 }

modules/apps/29-fee/keeper/events.go

@@ -9,17 +9,33 @@ import (
 	channeltypes "github.com/cosmos/ibc-go/v3/modules/core/04-channel/types"
 )
 
-// EmitIncentivizedPacket emits an event so that relayers know an incentivized packet is ready to be relayed
-func EmitIncentivizedPacket(ctx sdk.Context, packetID channeltypes.PacketId, packetFee types.PacketFee) {
+// EmitIncentivizedPacketEvent emits an event containing information on the total amount of fees incentivizing
+// a specific packet. It should be emitted on every fee escrowed for the given packetID.
+func EmitIncentivizedPacketEvent(ctx sdk.Context, packetID channeltypes.PacketId, packetFees types.PacketFees) {
+	var (
+		totalRecvFees    sdk.Coins
+		totalAckFees     sdk.Coins
+		totalTimeoutFees sdk.Coins
+	)
+
+	for _, fee := range packetFees.PacketFees {
+		// only emit total fees for packet fees which allow any relayer to relay
+		if fee.Relayers == nil {
+			totalRecvFees = totalRecvFees.Add(fee.Fee.RecvFee...)
+			totalAckFees = totalAckFees.Add(fee.Fee.AckFee...)
+			totalTimeoutFees = totalTimeoutFees.Add(fee.Fee.TimeoutFee...)
+		}
+	}
+
 	ctx.EventManager().EmitEvent(
 		sdk.NewEvent(
 			types.EventTypeIncentivizedPacket,
 			sdk.NewAttribute(channeltypes.AttributeKeyPortID, packetID.PortId),
 			sdk.NewAttribute(channeltypes.AttributeKeyChannelID, packetID.ChannelId),
 			sdk.NewAttribute(channeltypes.AttributeKeySequence, fmt.Sprint(packetID.Sequence)),
-			sdk.NewAttribute(types.AttributeKeyRecvFee, packetFee.Fee.RecvFee.String()),
-			sdk.NewAttribute(types.AttributeKeyAckFee, packetFee.Fee.AckFee.String()),
-			sdk.NewAttribute(types.AttributeKeyTimeoutFee, packetFee.Fee.TimeoutFee.String()),
+			sdk.NewAttribute(types.AttributeKeyRecvFee, totalRecvFees.String()),
+			sdk.NewAttribute(types.AttributeKeyAckFee, totalAckFees.String()),
+			sdk.NewAttribute(types.AttributeKeyTimeoutFee, totalTimeoutFees.String()),
 		),
 	)
 }

modules/apps/29-fee/keeper/events_test.go

@@ -0,0 +1,83 @@
+package keeper_test
+
+import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	abcitypes "github.com/tendermint/tendermint/abci/types"
+
+	"github.com/cosmos/ibc-go/v3/modules/apps/29-fee/types"
+)
+
+func (suite *KeeperTestSuite) TestIncentivizePacketEvent() {
+	var (
+		expRecvFees    sdk.Coins
+		expAckFees     sdk.Coins
+		expTimeoutFees sdk.Coins
+	)
+
+	suite.coordinator.Setup(suite.path)
+
+	fee := types.NewFee(defaultRecvFee, defaultAckFee, defaultTimeoutFee)
+	msg := types.NewMsgPayPacketFee(
+		fee,
+		suite.path.EndpointA.ChannelConfig.PortID,
+		suite.path.EndpointA.ChannelID,
+		suite.chainA.SenderAccount.GetAddress().String(),
+		nil,
+	)
+
+	expRecvFees = expRecvFees.Add(fee.RecvFee...)
+	expAckFees = expAckFees.Add(fee.AckFee...)
+	expTimeoutFees = expTimeoutFees.Add(fee.TimeoutFee...)
+
+	result, err := suite.chainA.SendMsgs(msg)
+	suite.Require().NoError(err)
+
+	var incentivizedPacketEvent abcitypes.Event
+	for _, event := range result.Events {
+		if event.Type == types.EventTypeIncentivizedPacket {
+			incentivizedPacketEvent = event
+		}
+	}
+
+	for _, attr := range incentivizedPacketEvent.Attributes {
+		switch string(attr.Key) {
+		case types.AttributeKeyRecvFee:
+			suite.Require().Equal(expRecvFees.String(), string(attr.Value))
+
+		case types.AttributeKeyAckFee:
+			suite.Require().Equal(expAckFees.String(), string(attr.Value))
+
+		case types.AttributeKeyTimeoutFee:
+			suite.Require().Equal(expTimeoutFees.String(), string(attr.Value))
+		}
+	}
+
+	// send the same messages again a few times
+	for i := 0; i < 3; i++ {
+		expRecvFees = expRecvFees.Add(fee.RecvFee...)
+		expAckFees = expAckFees.Add(fee.AckFee...)
+		expTimeoutFees = expTimeoutFees.Add(fee.TimeoutFee...)
+
+		result, err = suite.chainA.SendMsgs(msg)
+		suite.Require().NoError(err)
+	}
+
+	for _, event := range result.Events {
+		if event.Type == types.EventTypeIncentivizedPacket {
+			incentivizedPacketEvent = event
+		}
+	}
+
+	for _, attr := range incentivizedPacketEvent.Attributes {
+		switch string(attr.Key) {
+		case types.AttributeKeyRecvFee:
+			suite.Require().Equal(expRecvFees.String(), string(attr.Value))
+
+		case types.AttributeKeyAckFee:
+			suite.Require().Equal(expAckFees.String(), string(attr.Value))
+
+		case types.AttributeKeyTimeoutFee:
+			suite.Require().Equal(expTimeoutFees.String(), string(attr.Value))
+		}
+	}
+}