Merge pull request #10296 from hieblmi/estimate-inputs

estimatefee: tx fee estimate for selected inputs

cmd/commands/cmd_open_channel.go

@@ -16,6 +16,7 @@ import (
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
+	"github.com/lightningnetwork/lnd"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet/chanfunding"
 	"github.com/urfave/cli"
@@ -406,7 +407,7 @@ func openChannel(ctx *cli.Context) error {
 	if ctx.IsSet("utxo") {
 		utxos := ctx.StringSlice("utxo")
 
-		outpoints, err := UtxosToOutpoints(utxos)
+		outpoints, err := lnd.UtxosToOutpoints(utxos)
 		if err != nil {
 			return fmt.Errorf("unable to decode utxos: %w", err)
 		}

cmd/commands/commands.go

@@ -402,6 +402,14 @@ var estimateFeeCommand = cli.Command{
 				"transaction *should* confirm in",
 		},
 		coinSelectionStrategyFlag,
+		cli.StringSliceFlag{
+			Name: "utxo",
+			Usage: "a utxo specified as outpoint(tx:idx) which " +
+				"will be used as input for the transaction " +
+				"to be estimated. This flag can be " +
+				"repeatedly used to specify multiple utxos " +
+				"as inputs.",
+		},
 	},
 	Action: actionDecorator(estimateFees),
 }
@@ -423,10 +431,21 @@ func estimateFees(ctx *cli.Context) error {
 	client, cleanUp := getClient(ctx)
 	defer cleanUp()
 
+	var inputs []*lnrpc.OutPoint
+	if ctx.IsSet("utxo") {
+		utxos := ctx.StringSlice("utxo")
+
+		inputs, err = lnd.UtxosToOutpoints(utxos)
+		if err != nil {
+			return fmt.Errorf("unable to decode utxos: %w", err)
+		}
+	}
+
 	resp, err := client.EstimateFee(ctxc, &lnrpc.EstimateFeeRequest{
 		AddrToAmount:          amountToAddr,
 		TargetConf:            int32(ctx.Int64("conf_target")),
 		CoinSelectionStrategy: coinSelectionStrategy,
+		Inputs:                inputs,
 	})
 	if err != nil {
 		return err
@@ -607,7 +626,7 @@ func sendCoins(ctx *cli.Context) error {
 	if ctx.IsSet("utxo") {
 		utxos := ctx.StringSlice("utxo")
 
-		outpoints, err = UtxosToOutpoints(utxos)
+		outpoints, err = lnd.UtxosToOutpoints(utxos)
 		if err != nil {
 			return fmt.Errorf("unable to decode utxos: %w", err)
 		}
@@ -784,12 +803,12 @@ func listUnspent(ctx *cli.Context) error {
 	// to stdout. At the moment, this filters out the raw txid bytes from
 	// each utxo's outpoint and only prints the txid string.
 	var listUnspentResp = struct {
-		Utxos []*Utxo `json:"utxos"`
+		Utxos []*lnd.Utxo `json:"utxos"`
 	}{
-		Utxos: make([]*Utxo, 0, len(resp.Utxos)),
+		Utxos: make([]*lnd.Utxo, 0, len(resp.Utxos)),
 	}
 	for _, protoUtxo := range resp.Utxos {
-		utxo := NewUtxoFromProto(protoUtxo)
+		utxo := lnd.NewUtxoFromProto(protoUtxo)
 		listUnspentResp.Utxos = append(listUnspentResp.Utxos, utxo)
 	}
 
@@ -2789,12 +2808,14 @@ func updateChannelPolicy(ctx *cli.Context) error {
 	// to stdout. At the moment, this filters out the raw txid bytes from
 	// each failed update's outpoint and only prints the txid string.
 	var listFailedUpdateResp = struct {
-		FailedUpdates []*FailedUpdate `json:"failed_updates"`
+		FailedUpdates []*lnd.FailedUpdate `json:"failed_updates"`
 	}{
-		FailedUpdates: make([]*FailedUpdate, 0, len(resp.FailedUpdates)),
+		FailedUpdates: make(
+			[]*lnd.FailedUpdate, 0, len(resp.FailedUpdates),
+		),
 	}
 	for _, protoUpdate := range resp.FailedUpdates {
-		failedUpdate := NewFailedUpdateFromProto(protoUpdate)
+		failedUpdate := lnd.NewFailedUpdateFromProto(protoUpdate)
 		listFailedUpdateResp.FailedUpdates = append(
 			listFailedUpdateResp.FailedUpdates, failedUpdate)
 	}

cmd/commands/walletrpc_active.go

@@ -20,6 +20,7 @@ import (
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/txscript"
 	"github.com/btcsuite/btcd/wire"
+	"github.com/lightningnetwork/lnd"
 	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 	"github.com/lightningnetwork/lnd/lnwallet/chanfunding"
@@ -330,7 +331,7 @@ func bumpFee(ctx *cli.Context) error {
 	}
 
 	// Validate and parse the relevant arguments/flags.
-	protoOutPoint, err := NewProtoOutPoint(ctx.Args().Get(0))
+	protoOutPoint, err := lnd.NewProtoOutPoint(ctx.Args().Get(0))
 	if err != nil {
 		return err
 	}
@@ -812,11 +813,11 @@ func removeTransaction(ctx *cli.Context) error {
 
 // utxoLease contains JSON annotations for a lease on an unspent output.
 type utxoLease struct {
-	ID         string   `json:"id"`
-	OutPoint   OutPoint `json:"outpoint"`
-	Expiration uint64   `json:"expiration"`
-	PkScript   []byte   `json:"pk_script"`
-	Value      uint64   `json:"value"`
+	ID         string       `json:"id"`
+	OutPoint   lnd.OutPoint `json:"outpoint"`
+	Expiration uint64       `json:"expiration"`
+	PkScript   []byte       `json:"pk_script"`
+	Value      uint64       `json:"value"`
 }
 
 // fundPsbtResponse is a struct that contains JSON annotations for nice result
@@ -1358,7 +1359,7 @@ func fundPsbt(ctx *cli.Context) error {
 			}
 
 			for idx, input := range inputs {
-				op, err := NewProtoOutPoint(input)
+				op, err := lnd.NewProtoOutPoint(input)
 				if err != nil {
 					return fmt.Errorf("error parsing "+
 						"UTXO outpoint %d: %v", idx,
@@ -1447,7 +1448,7 @@ func marshallLocks(lockedUtxos []*walletrpc.UtxoLease) []*utxoLease {
 	for idx, lock := range lockedUtxos {
 		jsonLocks[idx] = &utxoLease{
 			ID:         hex.EncodeToString(lock.Id),
-			OutPoint:   NewOutPointFromProto(lock.Outpoint),
+			OutPoint:   lnd.NewOutPointFromProto(lock.Outpoint),
 			Expiration: lock.Expiration,
 			PkScript:   lock.PkScript,
 			Value:      lock.Value,
@@ -1578,7 +1579,7 @@ func leaseOutput(ctx *cli.Context) error {
 	}
 
 	outpointStr := ctx.String("outpoint")
-	outpoint, err := NewProtoOutPoint(outpointStr)
+	outpoint, err := lnd.NewProtoOutPoint(outpointStr)
 	if err != nil {
 		return fmt.Errorf("error parsing outpoint: %w", err)
 	}
@@ -1663,7 +1664,7 @@ func releaseOutput(ctx *cli.Context) error {
 		return fmt.Errorf("outpoint argument missing")
 	}
 
-	outpoint, err := NewProtoOutPoint(outpointStr)
+	outpoint, err := lnd.NewProtoOutPoint(outpointStr)
 	if err != nil {
 		return fmt.Errorf("error parsing outpoint: %w", err)
 	}

cmd/commands/walletrpc_types.go

@@ -1,6 +1,9 @@
 package commands
 
-import "github.com/lightningnetwork/lnd/lnrpc/walletrpc"
+import (
+	"github.com/lightningnetwork/lnd"
+	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
+)
 
 // PendingSweep is a CLI-friendly type of the walletrpc.PendingSweep proto. We
 // use this to show more useful string versions of byte slices and enums.
@@ -9,16 +12,16 @@ import "github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 // here. Instead, we should rely on the struct defined in the proto
 // `PendingSweepsResponse` only.
 type PendingSweep struct {
-	OutPoint             OutPoint `json:"outpoint"`
-	WitnessType          string   `json:"witness_type"`
-	AmountSat            uint32   `json:"amount_sat"`
-	SatPerVByte          uint32   `json:"sat_per_vbyte"`
-	BroadcastAttempts    uint32   `json:"broadcast_attempts"`
-	RequestedSatPerVByte uint32   `json:"requested_sat_per_vbyte"`
-	Immediate            bool     `json:"immediate"`
-	Budget               uint64   `json:"budget"`
-	DeadlineHeight       uint32   `json:"deadline_height"`
-	MaturityHeight       uint32   `json:"maturity_height"`
+	OutPoint             lnd.OutPoint `json:"outpoint"`
+	WitnessType          string       `json:"witness_type"`
+	AmountSat            uint32       `json:"amount_sat"`
+	SatPerVByte          uint32       `json:"sat_per_vbyte"`
+	BroadcastAttempts    uint32       `json:"broadcast_attempts"`
+	RequestedSatPerVByte uint32       `json:"requested_sat_per_vbyte"`
+	Immediate            bool         `json:"immediate"`
+	Budget               uint64       `json:"budget"`
+	DeadlineHeight       uint32       `json:"deadline_height"`
+	MaturityHeight       uint32       `json:"maturity_height"`
 
 	NextBroadcastHeight uint32 `json:"next_broadcast_height"`
 	RequestedConfTarget uint32 `json:"requested_conf_target"`
@@ -29,7 +32,9 @@ type PendingSweep struct {
 // its corresponding CLI-friendly type.
 func NewPendingSweepFromProto(pendingSweep *walletrpc.PendingSweep) *PendingSweep {
 	return &PendingSweep{
-		OutPoint:             NewOutPointFromProto(pendingSweep.Outpoint),
+		OutPoint: lnd.NewOutPointFromProto(
+			pendingSweep.Outpoint,
+		),
 		WitnessType:          pendingSweep.WitnessType.String(),
 		AmountSat:            pendingSweep.AmountSat,
 		SatPerVByte:          uint32(pendingSweep.SatPerVbyte),

docs/release-notes/release-notes-0.21.0.md

@@ -64,8 +64,16 @@
   it becomes available. These methods provide an alternative to the standard
   `MuSig2RegisterNonces` workflow and are only supported in MuSig2 v1.0.0rc2.
 
+* The `EstimateFee` RPC now supports [explicit input
+  selection](https://github.com/lightningnetwork/lnd/pull/10296). Users can
+  specify a list of inputs to use as transaction inputs via the new
+  `inputs` field in `EstimateFeeRequest`.
+
 ## lncli Additions
 
+* The `estimatefee` command now supports the `--utxos` flag to specify explicit
+  inputs for fee estimation.
+
 # Improvements
 ## Functional Updates
 
@@ -138,6 +146,7 @@
 * Boris Nagaev
 * Elle Mouton
 * Erick Cestari
+* hieblmi
 * Mohamed Awnallah
 * Nishant Bansal
 * Pins

itest/list_on_test.go

@@ -759,6 +759,14 @@ var allTestCases = []*lntest.TestCase{
 		Name:     "estimate fee",
 		TestFunc: testEstimateFee,
 	},
+	{
+		Name:     "estimate on chain fee with selected inputs",
+		TestFunc: testEstimateOnChainFeeWithSelectedInputs,
+	},
+	{
+		Name:     "estimate on chain fee auto selected inputs",
+		TestFunc: testEstimateOnChainFeeAutoSelectedInputs,
+	},
 }
 
 // appendPrefixed is used to add a prefix to each test name in the subtests

itest/lnd_estimate_on_chain_fee_test.go

@@ -0,0 +1,232 @@
+package itest
+
+import (
+	"fmt"
+
+	"github.com/btcsuite/btcd/btcutil"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
+	"github.com/lightningnetwork/lnd/lntest"
+	"github.com/stretchr/testify/require"
+)
+
+// testEstimateOnChainFeeWithSelectedInputs tests that the EstimateFee RPC
+// with specific input selection produces an accurate fee estimate that matches
+// the actual fee when sending coins with the same inputs.
+func testEstimateOnChainFeeWithSelectedInputs(ht *lntest.HarnessTest) {
+	// Create a new node for this test.
+	alice := ht.NewNode("Alice", nil)
+
+	// Fund Alice with multiple UTXOs of different amounts to give us
+	// several inputs to choose from.
+	const (
+		utxo1Amount = btcutil.Amount(500_000)
+		utxo2Amount = btcutil.Amount(300_000)
+		utxo3Amount = btcutil.Amount(200_000)
+		targetConf  = 2
+	)
+
+	ht.FundCoins(utxo1Amount, alice)
+	ht.FundCoins(utxo2Amount, alice)
+	ht.FundCoins(utxo3Amount, alice)
+
+	// List Alice's UTXOs to get their outpoints.
+	utxosResp := alice.RPC.ListUnspent(&walletrpc.ListUnspentRequest{
+		MinConfs: 1,
+		MaxConfs: 1000,
+	})
+	require.GreaterOrEqual(ht, len(utxosResp.Utxos), 3,
+		"expected at least 3 UTXOs")
+
+	// Create a lookup map to find outpoints by amount.
+	utxoLookup := make(map[int64]*lnrpc.OutPoint)
+	for _, utxo := range utxosResp.Utxos {
+		utxoLookup[utxo.AmountSat] = utxo.Outpoint
+	}
+
+	// Select the first two UTXOs for our test.
+	selectedInputs := []*lnrpc.OutPoint{
+		utxoLookup[int64(utxo1Amount)],
+		utxoLookup[int64(utxo2Amount)],
+	}
+	require.NotNil(ht, selectedInputs[0], "first UTXO not found")
+	require.NotNil(ht, selectedInputs[1], "second UTXO not found")
+
+	// Generate a destination address for the transaction.
+	destAddrResp := alice.RPC.NewAddress(&lnrpc.NewAddressRequest{
+		Type: lnrpc.AddressType_WITNESS_PUBKEY_HASH,
+	})
+
+	// Amount to send (less than the sum of selected UTXOs to allow for
+	// fees and change).
+	const sendAmount = int64(400_000)
+
+	// Create an address-to-amount map for the transaction.
+	addrToAmount := map[string]int64{
+		destAddrResp.Address: sendAmount,
+	}
+
+	// Call EstimateFee with the selected inputs.
+	estimateReq := &lnrpc.EstimateFeeRequest{
+		AddrToAmount: addrToAmount,
+		TargetConf:   targetConf,
+		Inputs:       selectedInputs,
+	}
+	estimateResp, err := alice.RPC.LN.EstimateFee(ht.Context(), estimateReq)
+	require.NoError(ht, err, "EstimateFee failed")
+
+	ht.Logf("Fee estimate: %d sats, fee rate: %d sat/vbyte",
+		estimateResp.FeeSat, estimateResp.SatPerVbyte)
+
+	// Verify that the estimate response includes the inputs we specified.
+	require.Len(ht, estimateResp.Inputs, 2,
+		"expected 2 inputs in estimate response")
+
+	// Create a map of input outpoints from the estimate for an easy lookup.
+	estimateInputs := make(map[string]bool)
+	for _, input := range estimateResp.Inputs {
+		key := fmt.Sprintf("%s:%d", input.TxidStr, input.OutputIndex)
+		estimateInputs[key] = true
+	}
+
+	// Verify each selected outpoint is in the estimate.
+	for _, outpoint := range selectedInputs {
+		key := fmt.Sprintf("%s:%d", outpoint.TxidStr,
+			outpoint.OutputIndex)
+
+		require.True(ht, estimateInputs[key],
+			"outpoint %s not found in estimate inputs", key)
+	}
+
+	// Now actually send coins using the same parameters.
+	sendReq := &lnrpc.SendCoinsRequest{
+		Addr:       destAddrResp.Address,
+		Amount:     sendAmount,
+		TargetConf: targetConf,
+		Outpoints:  selectedInputs,
+	}
+	sendResp := alice.RPC.SendCoins(sendReq)
+	txid := sendResp.Txid
+
+	ht.Logf("Transaction sent with txid: %s", txid)
+
+	// Get the transaction details to extract the actual fee paid.
+	txDetails := alice.RPC.GetTransactions(
+		&lnrpc.GetTransactionsRequest{
+			StartHeight: 0,
+			EndHeight:   -1,
+		},
+	)
+
+	// Find our transaction in the list.
+	var actualFee int64
+	var found bool
+	for _, tx := range txDetails.Transactions {
+		if tx.TxHash == txid {
+			actualFee = tx.TotalFees
+			found = true
+			ht.Logf("Actual fee paid: %d sats", actualFee)
+
+			break
+		}
+	}
+	require.True(ht, found, "sent transaction not found")
+
+	require.EqualValues(
+		ht, estimateResp.FeeSat, actualFee, "fee estimate does not "+
+			"match actual fee",
+	)
+
+	// Mine the SendCoinsRequest.
+	ht.MineBlocksAndAssertNumTxes(1, 1)
+}
+
+// testEstimateOnChainFeeAutoSelectedInputs tests that the EstimateFee RPC
+// without input selection allows the wallet to auto-select inputs, and that
+// using those selected inputs in SendCoins produces a matching fee.
+func testEstimateOnChainFeeAutoSelectedInputs(ht *lntest.HarnessTest) {
+	// Create a new node for this test.
+	alice := ht.NewNode("Alice", nil)
+
+	// Fund Alice with multiple UTXOs.
+	const (
+		utxo1Amount = btcutil.Amount(500_000)
+		utxo2Amount = btcutil.Amount(300_000)
+		utxo3Amount = btcutil.Amount(200_000)
+		targetConf  = 2
+	)
+
+	ht.FundCoins(utxo1Amount, alice)
+	ht.FundCoins(utxo2Amount, alice)
+	ht.FundCoins(utxo3Amount, alice)
+
+	// Generate a destination address.
+	destAddrResp := alice.RPC.NewAddress(
+		&lnrpc.NewAddressRequest{
+			Type: lnrpc.AddressType_WITNESS_PUBKEY_HASH,
+		},
+	)
+
+	const sendAmount = int64(100_000)
+	addrToAmount := map[string]int64{
+		destAddrResp.Address: sendAmount,
+	}
+
+	// Estimate fee without specifying inputs (wallet auto-selects).
+	estimateReq := &lnrpc.EstimateFeeRequest{
+		AddrToAmount: addrToAmount,
+		TargetConf:   targetConf,
+	}
+	estimateResp, err := alice.RPC.LN.EstimateFee(ht.Context(), estimateReq)
+	require.NoError(ht, err, "EstimateFee failed")
+
+	ht.Logf("Fee estimate (auto-select): %d sats, "+
+		"fee rate: %d sat/vbyte, inputs selected: %d",
+		estimateResp.FeeSat, estimateResp.SatPerVbyte,
+		len(estimateResp.Inputs))
+
+	// The estimate should have selected some inputs.
+	require.NotEmpty(ht, estimateResp.Inputs,
+		"estimate should have selected inputs")
+
+	// Send using the inputs that were selected by the estimate.
+	sendReq := &lnrpc.SendCoinsRequest{
+		Addr:       destAddrResp.Address,
+		Amount:     sendAmount,
+		TargetConf: targetConf,
+		Outpoints:  estimateResp.Inputs,
+	}
+	sendResp := alice.RPC.SendCoins(sendReq)
+	txid := sendResp.Txid
+
+	ht.Logf("Transaction sent with txid: %s", txid)
+
+	// Get the actual fee.
+	txDetails := alice.RPC.GetTransactions(
+		&lnrpc.GetTransactionsRequest{
+			StartHeight: 0,
+			EndHeight:   -1,
+		},
+	)
+
+	var actualFee int64
+	var found bool
+	for _, tx := range txDetails.Transactions {
+		if tx.TxHash == txid {
+			actualFee = tx.TotalFees
+			found = true
+			ht.Logf("Actual fee paid: %d sats", actualFee)
+
+			break
+		}
+	}
+	require.True(ht, found, "sent transaction not found")
+
+	require.EqualValues(
+		ht, estimateResp.FeeSat, actualFee, "fee estimate does not "+
+			"match actual fee",
+	)
+
+	// Mine the SendCoinsRequest.
+	ht.MineBlocksAndAssertNumTxes(1, 1)
+}

lnrpc/lightning.proto

@@ -1219,6 +1219,9 @@ message EstimateFeeRequest {
 
     // The strategy to use for selecting coins during fees estimation.
     CoinSelectionStrategy coin_selection_strategy = 5;
+
+    // A list of selected inputs for the transaction.
+    repeated OutPoint inputs = 6;
 }
 
 message EstimateFeeResponse {
@@ -1231,6 +1234,9 @@ message EstimateFeeResponse {
 
     // The fee rate in satoshi/vbyte.
     uint64 sat_per_vbyte = 3;
+
+    // A list of selected inputs for the transaction the estimate is for.
+    repeated OutPoint inputs = 4;
 }
 
 message SendManyRequest {

lnrpc/lightning.swagger.json

@@ -5038,6 +5038,14 @@
           "type": "string",
           "format": "uint64",
           "description": "The fee rate in satoshi/vbyte."
+        },
+        "inputs": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "$ref": "#/definitions/lnrpcOutPoint"
+          },
+          "description": "A list of selected inputs for the transaction the estimate is for."
         }
       }
     },

rpcserver.go

@@ -1275,14 +1275,29 @@ func (r *rpcServer) EstimateFee(ctx context.Context,
 		return nil, err
 	}
 
+	var selectOutpoints fn.Set[wire.OutPoint]
+	if len(in.Inputs) != 0 {
+		wireOutpoints, err := toWireOutpoints(in.Inputs)
+		if err != nil {
+			return nil, fmt.Errorf("can't create outpoints %w", err)
+		}
+
+		if fn.HasDuplicates(wireOutpoints) {
+			return nil, fmt.Errorf("selected outpoints contain " +
+				"duplicate values")
+		}
+
+		selectOutpoints = fn.NewSet(wireOutpoints...)
+	}
+
 	// We will ask the wallet to create a tx using this fee rate. We set
 	// dryRun=true to avoid inflating the change addresses in the db.
 	var tx *txauthor.AuthoredTx
 	wallet := r.server.cc.Wallet
 	err = wallet.WithCoinSelectLock(func() error {
 		tx, err = wallet.CreateSimpleTx(
-			nil, outputs, feePerKw, minConfs, coinSelectionStrategy,
-			true,
+			selectOutpoints, outputs, feePerKw, minConfs,
+			coinSelectionStrategy, true,
 		)
 		return err
 	})
@@ -1297,12 +1312,26 @@ func (r *rpcServer) EstimateFee(ctx context.Context,
 	}
 	totalFee := int64(tx.TotalInput) - totalOutput
 
+	// Return the inputs the estimate is for.
+	outStr := make([]string, 0, len(tx.Tx.TxIn))
+	for _, txIn := range tx.Tx.TxIn {
+		outStr = append(
+			outStr, txIn.PreviousOutPoint.String(),
+		)
+	}
+
+	inputs, err := UtxosToOutpoints(outStr)
+	if err != nil {
+		return nil, fmt.Errorf("can't convert outpoints %w", err)
+	}
+
 	resp := &lnrpc.EstimateFeeResponse{
 		FeeSat:      totalFee,
 		SatPerVbyte: uint64(feePerKw.FeePerVByte()),
 
 		// Deprecated field.
 		FeerateSatPerByte: int64(feePerKw.FeePerVByte()),
+		Inputs:            inputs,
 	}
 
 	rpcsLog.Debugf("[estimatefee] fee estimate for conf target %d: %v",

types.go

@@ -1,4 +1,4 @@
-package commands
+package lnd
 
 import (
 	"encoding/hex"