Add flags for setting fee limits for swaps (L2 routing) (#79)

* Flags limitQuoteFees and limitFeesL2, to set fee limits for swaps. The limitQuoteFees flag sets the fee ratio for swaps quotes, while the limitFeesL2 flag sets the fee ratio for swaps max routing fee.

* Docs update

* Add logging for max L2 routing fees in RequestReverseSubmarineSwap function

README.md

@@ -14,7 +14,8 @@ Flags:
       --backoffCoefficient float       Coefficient to apply to the backoff (default 0.95)
       --backoffLimit float             Limit coefficient of the backoff (default 0.1)
   -h, --help                           help for liquidator
-      --limitFees float                Limit fees for swaps e.g. 0.01 = 1% (default 0.007)
+      --limitFeesL2 float              Limit fee ratio for swaps max routing fee e.g. 0.01 = 1% (default 0.002)
+      --limitQuoteFees float           Limit fee ratio for swaps quotes (e.g. onchain+service fee estimation) e.g. 0.01 = 1% (default 0.005)
       --lndconnecturis string          CSV of lndconnect strings to connect to lnd(s)
       --logFormat string               Log format from: {text, json} (default "text")
       --logLevel string                Log level from values: {trace, debug, info, warn, error, fatal, panic} (default "info")
@@ -55,7 +56,8 @@ Available recipes:
 All the flags can be set as environment variables, with the following format, except stated, they are all mandatory:
 
 - LNDCONNECTURIS : CSV of lndconnect strings to connect to lnd(s)\
-- LIMITFEES (optional) : Limit to total Swap Fees (default 0.007 -> 0.7% Swap size)
+- LIMITQUOTEFEES (optional) : Limit to total Max Quote Fees (L1+service fee) (default 0.007 -> 0.7% of the Swap size)
+- LIMITFEESL2 (optional) : Limit to total Max Routing Fees (L2) (default 0.002 -> 0.2% of the Swap size)
 - LOOPDCONNECTURIS : CSV of loopdconnect strings to connect to loopd(s)
 - POLLINGINTERVAL (optional) : Interval to poll data(default 15s)
 - LOGLEVEL (optional) : Log level (default info) from: {trace, debug, info, warn, error, fatal, panic}

flags.go

@@ -113,9 +113,13 @@ func init() {
 	rootCmd.Flags().Float64("backoffLimit", 0.1, "Limit coefficient of the backoff")
 	viper.BindPFlag("backoffLimit", rootCmd.Flags().Lookup("backoffLimit"))
 
-	// Limit fees for swaps
-	rootCmd.Flags().Float64("limitFees", 0.007, "Limit fees for swaps e.g. 0.01 = 1%")
-	viper.BindPFlag("limitFees", rootCmd.Flags().Lookup("limitFees"))
+	// Limit fees for swaps quotes
+	rootCmd.Flags().Float64("limitQuoteFees", 0.005, "Limit fee ratio for swaps quotes (e.g. onchain+service fee estimation) e.g. 0.01 = 1%")
+	viper.BindPFlag("limitQuoteFees", rootCmd.Flags().Lookup("limitQuoteFees"))
+
+	// Limit fees for swaps L2
+	rootCmd.Flags().Float64("limitFeesL2", 0.002, "Limit fee ratio for swaps max routing fee e.g. 0.01 = 1%")
+	viper.BindPFlag("limitFeesL2", rootCmd.Flags().Lookup("limitFeesL2"))
 
 	//Sweep conf
 	rootCmd.Flags().String("sweepConfTarget", "400", "Target number of confirmations for swaps, this uses bitcoin core broken estimator, procced with caution")
@@ -131,7 +135,6 @@ func init() {
 	retries = viper.GetInt("retriesBeforeBackoff")
 	backoffCoefficient = viper.GetFloat64("backoffCoefficient")
 	backoffLimit = viper.GetFloat64("backoffLimit")
-	limitFees = viper.GetFloat64("limitFees")
 
 	//Set log level and format
 

liquidator.go

@@ -36,7 +36,6 @@ var (
 	retries            int
 	backoffCoefficient float64
 	backoffLimit       float64
-	limitFees          float64
 )
 
 // Entrypoint of liquidator main logic

provider/loop_provider.go

@@ -61,7 +61,7 @@ func (l *LoopProvider) RequestSubmarineSwap(ctx context.Context, request Submari
 		return SubmarineSwapResponse{}, err
 	}
 
-	limitFeesStr := viper.GetString("LIMITFEES")
+	limitFeesStr := viper.GetString("limitQuoteFees")
 	limitFees, err := strconv.ParseFloat(limitFeesStr, 64)
 	if err != nil {
 		return SubmarineSwapResponse{}, err
@@ -228,8 +228,8 @@ func (l *LoopProvider) RequestReverseSubmarineSwap(ctx context.Context, request
 
 	//Do a quote for loop out
 	quote, err := client.LoopOutQuote(ctx, &looprpc.QuoteRequest{
-		Amt: request.SatsAmount,
-		//ConfTarget:   1, //TODO Make this configurable
+		Amt:          request.SatsAmount,
+		ConfTarget:   viper.GetInt32("sweepConfTarget"),
 		ExternalHtlc: true,
 		Private:      false,
 	})
@@ -239,21 +239,24 @@ func (l *LoopProvider) RequestReverseSubmarineSwap(ctx context.Context, request
 		return ReverseSubmarineSwapResponse{}, err
 	}
 
-	limitFeesStr := viper.GetString("LIMITFEES")
-	limitFees, err := strconv.ParseFloat(limitFeesStr, 64)
-	if err != nil {
-		return ReverseSubmarineSwapResponse{}, err
-	}
+	limitQuoteFees := viper.GetFloat64("limitQuoteFees")
 
+	//This fees are onchain + service fees, NOT L2 fees as they are not in the quote
 	sumFees := quote.SwapFeeSat + quote.HtlcSweepFeeSat + quote.PrepayAmtSat
-	maximumFeesAllowed := int64(float64(request.SatsAmount) * limitFees)
+	maximumFeesAllowed := int64(float64(request.SatsAmount) * limitQuoteFees)
 
 	if sumFees > maximumFeesAllowed {
-		err := fmt.Errorf("swap fees are greater than max limit fees, quote fees: %d, maximum fees allowed: %d", sumFees, maximumFeesAllowed)
+		err := fmt.Errorf("swap quote fees (L1+Service estimation fees) are greater than max limit fees, quote fees: %d, maximum fees allowed: %d", sumFees, maximumFeesAllowed)
 		log.Error(err)
 		return ReverseSubmarineSwapResponse{}, err
 	}
 
+	//Max swap routing fee (L2 fees) is a percentage of the swap amount
+	l2MaxRoutingFeeRatio := viper.GetFloat64("limitFeesL2")
+	maxSwapRoutingFee := int64(float64(request.SatsAmount) * l2MaxRoutingFeeRatio)
+
+	log.Infof("max L2 routing fees for the swap: %d", maxSwapRoutingFee)
+
 	//Get limits
 	//Amt using btcutil
 	amt := btcutil.Amount(request.SatsAmount)
@@ -270,13 +273,13 @@ func (l *LoopProvider) RequestReverseSubmarineSwap(ctx context.Context, request
 		MaxPrepayAmt:        int64(limits.maxPrepayAmt),
 		MaxSwapFee:          int64(limits.maxSwapFee),
 		MaxPrepayRoutingFee: int64(limits.maxPrepayRoutingFee),
-		MaxSwapRoutingFee:   int64(limits.maxSwapRoutingFee),
+		MaxSwapRoutingFee:   maxSwapRoutingFee,
 		OutgoingChanSet:     request.ChannelSet,
 		SweepConfTarget:     viper.GetInt32("sweepConfTarget"),
 		HtlcConfirmations:   3,
 		//The publication deadline is maximum the offset of the swap deadline conf plus the current time
 		SwapPublicationDeadline: uint64(time.Now().Add(viper.GetDuration("swapPublicationOffset") * time.Minute).Unix()),
-		Label:                   fmt.Sprintf("Reverse submarine swap %d sats on date %s", request.SatsAmount, time.Now().Format(time.RFC3339)),
+		Label:                   fmt.Sprintf("Reverse submarine swap %d sats on date %s for channels: %v", request.SatsAmount, time.Now().Format(time.RFC3339), request.ChannelSet),
 		Initiator:               "Liquidator",
 	})
 

provider/loop_provider_test.go

@@ -12,13 +12,23 @@ import (
 	gomock "go.uber.org/mock/gomock"
 )
 
+func TestMain(m *testing.M) {
+
+	setLimitFees()
+
+	m.Run()
+}
+
+func setLimitFees() {
+	viper.Set("limitQuoteFees", "0.005")
+	viper.Set("limitFeesL2", "0.002")
+}
+
 func TestLoopProvider_RequestSubmarineSwap(t *testing.T) {
 
 	ctrl := gomock.NewController(t)
 	defer ctrl.Finish()
 
-	viper.Set("LIMITFEES", "0.007")
-
 	//Mock lightning swapClient GetLoopInQuote and LoopIn methods to return fake data
 	swapClient := NewMockSwapClientClient(ctrl)