Fix #37

feat(liquidator.go): add check for swapAmount exceeding maxPendingLocalSats and adjust accordingly (#37)
test(liquidator_test.go): add test case for managing channel liquidity bypassing max pending amount
feat(loop_provider.go): adjust SweepConfTarget and HtlcConfirmations from 2 to 3 for better reliability
style: remove unnecessary blank lines and adjust indentation for better code readability
chore: update loop subproject commit hash

liquidator.go

@@ -132,7 +132,6 @@ func startLiquidator() {
 			log.Fatal("failed to generate context with macaroon")
 		}
 
-
 		//Get the local node info
 		nodeInfo, err := getLocalNodeInfo(lightningClient, nodeContext)
 		if err != nil {
@@ -349,22 +348,18 @@ func monitorChannel(info MonitorChannelInfo) {
 
 	channelRules := info.liquidationRules[info.channel.GetChanId()]
 
-	if len(info.channel.PendingHtlcs) == 0 {
-		//Manage liquidity if there are no pending htlcs
-		err = manageChannelLiquidity(ManageChannelLiquidityInfo{
-			channel:             info.channel,
-			channelBalanceRatio: channelBalanceRatio,
-			channelRules:        &channelRules,
-			swapClientClient:    info.swapClient,
-			nodeguardClient:     info.nodeguardClient,
-			loopProvider:        info.loopProvider,
-			loopdMacaroon:       info.loopdMacaroon,
-			nodeInfo:            info.nodeInfo,
-			ctx:                 spanCtx,
-		})
-	} else {
-		log.WithField("span", span).Debugf("channel: %v has pending htlcs, skipping liquidity management", info.channel.GetChanId())
-	}
+	//Manage liquidity if there are no pending htlcs
+	err = manageChannelLiquidity(ManageChannelLiquidityInfo{
+		channel:             info.channel,
+		channelBalanceRatio: channelBalanceRatio,
+		channelRules:        &channelRules,
+		swapClientClient:    info.swapClient,
+		nodeguardClient:     info.nodeguardClient,
+		loopProvider:        info.loopProvider,
+		loopdMacaroon:       info.loopdMacaroon,
+		nodeInfo:            info.nodeInfo,
+		ctx:                 spanCtx,
+	})
 
 	if err != nil {
 
@@ -448,6 +443,13 @@ func manageChannelLiquidity(info ManageChannelLiquidityInfo) error {
 			//Calculate the swap amount
 			swapAmount := helper.AbsInt64((channel.RemoteBalance - swapAmountTarget))
 
+			// if the swapAmount is bigger than max pending htlc amount, set it to max pending htlc amount
+			maxPendingLocalSats := int64(channel.GetLocalConstraints().GetMaxPendingAmtMsat() / 1000)
+			if swapAmount > maxPendingLocalSats && maxPendingLocalSats > 0 {
+				swapAmount = maxPendingLocalSats
+				log.WithField("span",span).Infof("swap amount is bigger than max pending htlc amount, setting it to max pending htlc amount: %v", maxPendingLocalSats)
+			}
+
 			//Request nodeguard a new destination address for the reverse swap
 			walletRequest := &nodeguard.GetNewWalletAddressRequest{
 				WalletId: rule.WalletId,

liquidator_test.go

@@ -113,6 +113,14 @@ func Test_manageChannelLiquidity(t *testing.T) {
 		LocalBalance:  100,
 		RemoteBalance: 900,
 		RemotePubkey:  "03485d8dcdd149c87553eeb80586eb2bece874d412e9f117304446ce189955d375",
+		LocalConstraints: &lnrpc.ChannelConstraints{
+			CsvDelay:          144,
+			ChanReserveSat:    250,
+			DustLimitSat:      300,
+			MaxPendingAmtMsat: 300*1000,
+			MinHtlcMsat:       350 * 1000,
+			MaxAcceptedHtlcs:  30,
+		},
 	}
 
 	nodeInfo := lnrpc.GetInfoResponse{
@@ -137,6 +145,20 @@ func Test_manageChannelLiquidity(t *testing.T) {
 				ctx:                 context.TODO(),
 			},
 			wantErr: false,
+		},
+				{
+			name: "Manage channel liquidity test valid reverse swap bypassing max pending amt",
+			args: ManageChannelLiquidityInfo{
+				channel:             channelActive,
+				channelBalanceRatio: 0.1,
+				channelRules:        &[]nodeguard.LiquidityRule{{ChannelId: 123, NodePubkey: "", WalletId: 1, MinimumLocalBalance: 20, MinimumRemoteBalance: 80, RebalanceTarget: 40}},
+				nodeguardClient:     mockNodeGuardClient,
+				loopProvider:        mockProvider,
+				loopdMacaroon:       "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",
+				nodeInfo:            nodeInfo,
+				ctx:                 context.TODO(),
+			},
+			wantErr: false,
 		},
 		{
 			name: "Manage channel liquidity test valid swap",

provider/loop_provider.go

@@ -234,16 +234,16 @@ func (l *LoopProvider) RequestReverseSubmarineSwap(ctx context.Context, request
 
 	//Use the client to request the swap
 	resp, err := client.LoopOut(ctx, &looprpc.LoopOutRequest{
-		Amt:                     request.SatsAmount,
-		Dest:                    request.ReceiverBTCAddress,
-		MaxMinerFee:             int64(limits.maxMinerFee),
-		MaxPrepayAmt:            int64(limits.maxPrepayAmt),
-		MaxSwapFee:              int64(limits.maxSwapFee),
-		MaxPrepayRoutingFee:     int64(limits.maxPrepayRoutingFee),
-		MaxSwapRoutingFee:       int64(limits.maxSwapRoutingFee),
-		OutgoingChanSet:         request.ChannelSet,
-		SweepConfTarget:         2, //TODO Make this configurable
-		HtlcConfirmations:       2,
+		Amt:                 request.SatsAmount,
+		Dest:                request.ReceiverBTCAddress,
+		MaxMinerFee:         int64(limits.maxMinerFee),
+		MaxPrepayAmt:        int64(limits.maxPrepayAmt),
+		MaxSwapFee:          int64(limits.maxSwapFee),
+		MaxPrepayRoutingFee: int64(limits.maxPrepayRoutingFee),
+		MaxSwapRoutingFee:   int64(limits.maxSwapRoutingFee),
+		OutgoingChanSet:     request.ChannelSet,
+		SweepConfTarget:     3, //TODO Make this configurable
+		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)),

provider/loop_provider_test.go

@@ -366,12 +366,12 @@ func Test_checkSubmarineSwapNotInProgress(t *testing.T) {
 	swapClientWithOngoingSwaps.EXPECT().ListSwaps(gomock.Any(), gomock.Any()).Return(&looprpc.ListSwapsResponse{
 		Swaps: []*looprpc.SwapStatus{
 			{
-				Amt:              0,
-				Id:               "",
-				IdBytes:          idBytes,
-				Type:             looprpc.SwapType_LOOP_IN,
-				State:            looprpc.SwapState_INITIATED,
-				FailureReason:    0,
+				Amt:           0,
+				Id:            "",
+				IdBytes:       idBytes,
+				Type:          looprpc.SwapType_LOOP_IN,
+				State:         looprpc.SwapState_INITIATED,
+				FailureReason: 0,
 				//InitiationTime 4 hours ago
 				InitiationTime:   time.Now().Add(-4 * time.Hour).UnixNano(),
 				LastUpdateTime:   time.Now().Add(-4 * time.Hour).UnixNano(),
@@ -393,12 +393,12 @@ func Test_checkSubmarineSwapNotInProgress(t *testing.T) {
 	swapClientWithNoOngoingSwaps.EXPECT().ListSwaps(gomock.Any(), gomock.Any()).Return(&looprpc.ListSwapsResponse{
 		Swaps: []*looprpc.SwapStatus{
 			{
-				Amt:              0,
-				Id:               "",
-				IdBytes:          idBytes,
-				Type:             looprpc.SwapType_LOOP_IN,
-				State:            looprpc.SwapState_INITIATED,
-				FailureReason:    0,
+				Amt:           0,
+				Id:            "",
+				IdBytes:       idBytes,
+				Type:          looprpc.SwapType_LOOP_IN,
+				State:         looprpc.SwapState_INITIATED,
+				FailureReason: 0,
 				//InitiationTime is more than 24 hours ago, stuck but ignored
 				InitiationTime:   time.Now().Add(-25 * time.Hour).UnixNano(),
 				LastUpdateTime:   time.Now().Add(-25 * time.Hour).UnixNano(),

rpc/rpc_test.go

@@ -113,7 +113,6 @@ func TestCreateSwapClientClient(t *testing.T) {
 					Cert:     tlsCertEncoded,
 					Macaroon: "0201036c6e6402f801030a101ec5b6370c166f6c8e2853164109145a1201301a160a0761646472657373120472656164120577726974651a130a04696e666f120472656164120577726974651a170a08696e766f69636573120472656164120577726974651a210a086d616361726f6f6e120867656e6572617465120472656164120577726974651a160a076d657373616765120472656164120577726974651a170a086f6666636861696e120472656164120577726974651a160a076f6e636861696e120472656164120577726974651a140a057065657273120472656164120577726974651a180a067369676e6572120867656e6572617465120472656164000006208e957e78ec39e7810fad25cfc43850b8e9e7c079843b8ec7bb5522bba12230d6",
 				},
-
 			},
 			wantErr: false,
 		},