fix(*): handle dest rollback

example/contracts/src/transfer/transfer.go

@@ -118,7 +118,7 @@ func (t *Transfer) transfer(stub shim.ChaincodeStubInterface, args []string) pb.
 			return shim.Error(err.Error())
 		}
 
-		args := strings.Join([]string{sender, receiver, amountArg}, ",")
+		args := strings.Join([]string{sender, receiver, amountArg, "true"}, ",")
 		argsRb := strings.Join([]string{sender, amountArg}, ",")
 		b := util.ToChaincodeArgs(emitInterchainEventFunc, dstServiceID, "interchainCharge,,interchainRollback", args, "", argsRb)
 		response := stub.InvokeChaincode(brokerContractName, b, channelID)
@@ -173,6 +173,7 @@ func (t *Transfer) interchainCharge(stub shim.ChaincodeStubInterface, args []str
 	sender := args[0]
 	receiver := args[1]
 	amountArg := args[2]
+	isRollback := args[3]
 
 	// check for sender info
 	if sender == "" {
@@ -189,7 +190,12 @@ func (t *Transfer) interchainCharge(stub shim.ChaincodeStubInterface, args []str
 		return shim.Error(fmt.Errorf("get balancee from %s %w", receiver, err).Error())
 	}
 
-	balance += amount
+	// TODO: deal with rollback failure (balance not enough)
+	if isRollback == "true" {
+		balance -= amount
+	} else {
+		balance += amount
+	}
 	err = stub.PutState(receiver, []byte(strconv.FormatUint(balance, 10)))
 	if err != nil {
 		return shim.Error(err.Error())