Merge pull request #933 from lightninglabs/autoloop-slow-by-default

liquidity: default to slow swaps for autloop

Author: bhandras

cmd/loop/liquidity.go

@@ -367,6 +367,16 @@ var setParamsCommand = cli.Command{
 			Usage: "the target size of total local balance in " +
 				"asset units, used by asset easy autoloop.",
 		},
+		cli.BoolFlag{
+			Name: "fast",
+			Usage: "if set new swaps are expected to be " +
+				"published immediately, paying a potentially " +
+				"higher fee. If not set the swap server " +
+				"might choose to wait up to 30 minutes " +
+				"before publishing swap HTLCs on-chain, to " +
+				"save on chain fees. Not setting this flag " +
+				"therefore might result in a lower swap fees",
+		},
 	},
 	Action: setParams,
 }
@@ -577,6 +587,10 @@ func setParams(ctx *cli.Context) error {
 		flagSet = true
 	}
 
+	if ctx.IsSet("fast") {
+		params.FastSwapPublication = true
+	}
+
 	if !flagSet {
 		return fmt.Errorf("at least one flag required to set params")
 	}

liquidity/autoloop_test.go

@@ -117,7 +117,8 @@ func TestAutoLoopEnabled(t *testing.T) {
 				chanID1: chanRule,
 				chanID2: chanRule,
 			},
-			HtlcConfTarget: defaultHtlcConfTarget,
+			HtlcConfTarget:      defaultHtlcConfTarget,
+			FastSwapPublication: true,
 		}
 	)
 
@@ -376,7 +377,8 @@ func TestAutoloopAddress(t *testing.T) {
 				chanID1: chanRule,
 				chanID2: chanRule,
 			},
-			HtlcConfTarget: defaultHtlcConfTarget,
+			HtlcConfTarget:      defaultHtlcConfTarget,
+			FastSwapPublication: true,
 		}
 	)
 	c := newAutoloopTestCtx(t, params, channels, testRestrictions)
@@ -546,7 +548,8 @@ func TestCompositeRules(t *testing.T) {
 			PeerRules: map[route.Vertex]*SwapRule{
 				peer2: chanRule,
 			},
-			HtlcConfTarget: defaultHtlcConfTarget,
+			HtlcConfTarget:      defaultHtlcConfTarget,
+			FastSwapPublication: true,
 		}
 	)
 
@@ -923,8 +926,9 @@ func TestAutoloopBothTypes(t *testing.T) {
 			PeerRules: map[route.Vertex]*SwapRule{
 				peer2: inRule,
 			},
-			HtlcConfTarget:  htlcConfTarget,
-			SweepConfTarget: loop.DefaultSweepConfTarget,
+			HtlcConfTarget:      htlcConfTarget,
+			SweepConfTarget:     loop.DefaultSweepConfTarget,
+			FastSwapPublication: false,
 		}
 	)
 	c := newAutoloopTestCtx(t, params, channels, testRestrictions)
@@ -939,9 +943,11 @@ func TestAutoloopBothTypes(t *testing.T) {
 		}
 
 		loopOutQuoteReq = &loop.LoopOutQuoteRequest{
-			Amount:                  loopOutAmt,
-			SweepConfTarget:         params.SweepConfTarget,
-			SwapPublicationDeadline: testTime,
+			Amount:          loopOutAmt,
+			SweepConfTarget: params.SweepConfTarget,
+			SwapPublicationDeadline: c.testClock.Now().Add(
+				defaultSwapPublicationWaitTime,
+			),
 		}
 
 		prepayMaxFee, routeMaxFee,
@@ -962,6 +968,9 @@ func TestAutoloopBothTypes(t *testing.T) {
 			},
 			Label:     labels.AutoloopLabel(swap.TypeOut),
 			Initiator: autoloopSwapInitiator,
+			SwapPublicationDeadline: c.testClock.Now().Add(
+				defaultSwapPublicationWaitTime,
+			),
 		}
 
 		loopinQuote = &loop.LoopInQuote{
@@ -1069,7 +1078,8 @@ func TestAutoLoopRecurringBudget(t *testing.T) {
 				chanID1: chanRule,
 				chanID2: chanRule,
 			},
-			HtlcConfTarget: defaultHtlcConfTarget,
+			HtlcConfTarget:      defaultHtlcConfTarget,
+			FastSwapPublication: true,
 		}
 	)
 
@@ -1320,6 +1330,7 @@ func TestEasyAutoloop(t *testing.T) {
 			EasyAutoloop:              true,
 			EasyAutoloopTarget:        75000,
 			FeeLimit:                  defaultFeePortion(),
+			FastSwapPublication:       true,
 		}
 	)
 

liquidity/loopout_builder.go

@@ -3,6 +3,7 @@ package liquidity
 import (
 	"context"
 	"encoding/hex"
+	"time"
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/lightninglabs/loop"
@@ -14,6 +15,12 @@ import (
 	"github.com/lightningnetwork/lnd/routing/route"
 )
 
+const (
+	// defaultSwapWaitTime is the default time we set as the deadline by
+	// which we expect the swap to be published.
+	defaultSwapPublicationWaitTime = 30 * time.Minute
+)
+
 // Compile-time assertion that loopOutBuilder satisfies the swapBuilder
 // interface.
 var _ swapBuilder = (*loopOutBuilder)(nil)
@@ -151,11 +158,18 @@ func (b *loopOutBuilder) buildSwap(ctx context.Context, pubkey route.Vertex,
 		initiator += "-" + assetSwap.assetID
 	}
 
+	var swapPublicationDeadline time.Time
+	if !params.FastSwapPublication {
+		swapPublicationDeadline = b.cfg.Clock.Now().Add(
+			defaultSwapPublicationWaitTime,
+		)
+	}
+
 	quote, err := b.cfg.LoopOutQuote(
 		ctx, &loop.LoopOutQuoteRequest{
 			Amount:                  amount,
 			SweepConfTarget:         params.SweepConfTarget,
-			SwapPublicationDeadline: b.cfg.Clock.Now(),
+			SwapPublicationDeadline: swapPublicationDeadline,
 			Initiator:               initiator,
 			AssetRFQRequest:         assetRfqRequest,
 		},
@@ -193,16 +207,17 @@ func (b *loopOutBuilder) buildSwap(ctx context.Context, pubkey route.Vertex,
 	// swap fee, prepay amount and miner fee from the quote because we have
 	// already validated them.
 	request := loop.OutRequest{
-		Amount:              amount,
-		IsExternalAddr:      false,
-		OutgoingChanSet:     chanSet,
-		MaxPrepayRoutingFee: prepayMaxFee,
-		MaxSwapRoutingFee:   routeMaxFee,
-		MaxMinerFee:         minerFee,
-		MaxSwapFee:          quote.SwapFee,
-		MaxPrepayAmount:     quote.PrepayAmount,
-		SweepConfTarget:     params.SweepConfTarget,
-		Initiator:           initiator,
+		Amount:                  amount,
+		IsExternalAddr:          false,
+		OutgoingChanSet:         chanSet,
+		MaxPrepayRoutingFee:     prepayMaxFee,
+		MaxSwapRoutingFee:       routeMaxFee,
+		MaxMinerFee:             minerFee,
+		MaxSwapFee:              quote.SwapFee,
+		MaxPrepayAmount:         quote.PrepayAmount,
+		SweepConfTarget:         params.SweepConfTarget,
+		Initiator:               initiator,
+		SwapPublicationDeadline: swapPublicationDeadline,
 	}
 
 	if opts.assetSwap != nil {

liquidity/parameters.go

@@ -31,6 +31,7 @@ var (
 		SweepConfTarget:           defaultConfTarget,
 		HtlcConfTarget:            defaultHtlcConfTarget,
 		FeeLimit:                  defaultFeePortion(),
+		FastSwapPublication:       true,
 	}
 )
 
@@ -118,6 +119,11 @@ type Parameters struct {
 	// AssetAutoloopParams maps an asset id hex encoded string to its
 	// easy autoloop parameters.
 	AssetAutoloopParams map[string]AssetParams
+
+	// FastSwapPublication controls publication deadline for new loop out
+	// swaps. If set to true, the deadline is set to immediate publication.
+	// If set to false, the deadline is set to 30 minutes.
+	FastSwapPublication bool
 }
 
 // AssetParams define the asset specific autoloop parameters.
@@ -460,10 +466,13 @@ func RpcToParameters(req *clientrpc.LiquidityParameters) (*Parameters,
 			Minimum: btcutil.Amount(req.MinSwapAmount),
 			Maximum: btcutil.Amount(req.MaxSwapAmount),
 		},
-		HtlcConfTarget:      req.HtlcConfTarget,
-		EasyAutoloop:        req.EasyAutoloop,
-		EasyAutoloopTarget:  btcutil.Amount(req.EasyAutoloopLocalTargetSat),
+		HtlcConfTarget: req.HtlcConfTarget,
+		EasyAutoloop:   req.EasyAutoloop,
+		EasyAutoloopTarget: btcutil.Amount(
+			req.EasyAutoloopLocalTargetSat,
+		),
 		AssetAutoloopParams: easyAssetParams,
+		FastSwapPublication: req.FastSwapPublication,
 	}
 
 	if req.AutoloopBudgetRefreshPeriodSec != 0 {
@@ -592,6 +601,7 @@ func ParametersToRpc(cfg Parameters) (*clientrpc.LiquidityParameters,
 		Account:                    cfg.Account,
 		AccountAddrType:            addrType,
 		EasyAssetParams:            easyAssetMap,
+		FastSwapPublication:        cfg.FastSwapPublication,
 	}
 
 	switch f := cfg.FeeLimit.(type) {