Simplify coin selection for sendcoins

cmd/lncli/cmd_open_channel.go

@@ -406,7 +406,7 @@ func openChannel(ctx *cli.Context) error {
 	if ctx.IsSet("utxo") {
 		utxos := ctx.StringSlice("utxo")
 
-		outpoints, err := utxosToOutpoints(utxos)
+		outpoints, err := UtxosToOutpoints(utxos)
 		if err != nil {
 			return fmt.Errorf("unable to decode utxos: %w", err)
 		}
@@ -1141,21 +1141,3 @@ func decodePsbt(psbt string) ([]byte, error) {
 		return nil, fmt.Errorf("not a PSBT")
 	}
 }
-
-// parseUtxos parses a comma separated list of utxos into outpoints that are
-// passed to the server.
-func utxosToOutpoints(utxos []string) ([]*lnrpc.OutPoint, error) {
-	var outpoints []*lnrpc.OutPoint
-	if len(utxos) == 0 {
-		return nil, fmt.Errorf("no utxos specified")
-	}
-	for _, utxo := range utxos {
-		outpoint, err := NewProtoOutPoint(utxo)
-		if err != nil {
-			return nil, err
-		}
-		outpoints = append(outpoints, outpoint)
-	}
-
-	return outpoints, nil
-}

cmd/lncli/commands.go

@@ -288,10 +288,11 @@ var sendCoinsCommand = cli.Command{
 		},
 		cli.BoolFlag{
 			Name: "sweepall",
-			Usage: "if set, then the amount field will be ignored, " +
-				"and the wallet will attempt to sweep all " +
-				"outputs within the wallet to the target " +
-				"address",
+			Usage: "if set, then the amount field should be " +
+				"unset. This indicates that the wallet will " +
+				"attempt to sweep all outputs within the " +
+				"wallet or all funds in select utxos (when " +
+				"supplied) to the target address",
 		},
 		cli.Int64Flag{
 			Name:  "amt",
@@ -330,16 +331,28 @@ var sendCoinsCommand = cli.Command{
 				"scripts",
 		},
 		coinSelectionStrategyFlag,
+		cli.StringSliceFlag{
+			Name: "utxo",
+			Usage: "a utxo specified as outpoint(tx:idx) which " +
+				"will be used as input for the transaction. " +
+				"This flag can be repeatedly used to specify " +
+				"multiple utxos as inputs. The selected " +
+				"utxos can either be entirely spent by " +
+				"specifying the sweepall flag or a specified " +
+				"amount can be spent in the utxos through " +
+				"the amt flag",
+		},
 		txLabelFlag,
 	},
 	Action: actionDecorator(sendCoins),
 }
 
 func sendCoins(ctx *cli.Context) error {
 	var (
-		addr string
-		amt  int64
-		err  error
+		addr      string
+		amt       int64
+		err       error
+		outpoints []*lnrpc.OutPoint
 	)
 	ctxc := getContext()
 	args := ctx.Args()
@@ -417,6 +430,15 @@ func sendCoins(ctx *cli.Context) error {
 		displayAmt = balanceResponse.GetConfirmedBalance()
 	}
 
+	if ctx.IsSet("utxo") {
+		utxos := ctx.StringSlice("utxo")
+
+		outpoints, err = UtxosToOutpoints(utxos)
+		if err != nil {
+			return fmt.Errorf("unable to decode utxos: %w", err)
+		}
+	}
+
 	// Ask for confirmation if we're on an actual terminal and the output is
 	// not being redirected to another command. This prevents existing shell
 	// scripts from breaking.
@@ -440,6 +462,7 @@ func sendCoins(ctx *cli.Context) error {
 		MinConfs:              minConfs,
 		SpendUnconfirmed:      minConfs == 0,
 		CoinSelectionStrategy: coinSelectionStrategy,
+		Outpoints:             outpoints,
 	}
 	txid, err := client.SendCoins(ctxc, req)
 	if err != nil {

cmd/lncli/types.go

@@ -85,3 +85,22 @@ func NewFailedUpdateFromProto(update *lnrpc.FailedUpdate) *FailedUpdate {
 		UpdateError: update.UpdateError,
 	}
 }
+
+// UtxosToOutpoints converts a slice of UTXO strings into a slice of OutPoint
+// protobuf objects. It returns an error if no UTXOs are specified or if any
+// UTXO string cannot be parsed into an OutPoint.
+func UtxosToOutpoints(utxos []string) ([]*lnrpc.OutPoint, error) {
+	var outpoints []*lnrpc.OutPoint
+	if len(utxos) == 0 {
+		return nil, fmt.Errorf("no utxos specified")
+	}
+	for _, utxo := range utxos {
+		outpoint, err := NewProtoOutPoint(utxo)
+		if err != nil {
+			return nil, err
+		}
+		outpoints = append(outpoints, outpoint)
+	}
+
+	return outpoints, nil
+}

docs/release-notes/release-notes-0.18.1.md

@@ -42,6 +42,9 @@
 * [`ChanInfoRequest`](https://github.com/lightningnetwork/lnd/pull/8813)
   adds support for channel points.
 
+* [Added `outpoints` to `SendCoinsRequest`](
+  https://github.com/lightningnetwork/lnd/pull/8516).
+
 ## lncli Updates
 
 * [`importmc`](https://github.com/lightningnetwork/lnd/pull/8779) now accepts
@@ -53,6 +56,10 @@
 * [Fixed](https://github.com/lightningnetwork/lnd/pull/8823) how we parse the
   `--amp` flag when sending a payment specifying the payment request.
 
+* [`sendcoins` now takes an optional utxo flag](
+    https://github.com/lightningnetwork/lnd/pull/8516). This allows users to
+    specify the coins that they want to use as inputs for the transaction.
+
 ## Code Health
 ## Breaking Changes
 ## Performance Improvements

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/btcsuite/btcwallet v0.16.10-0.20240404104514-b2f31f9045fb
 	github.com/btcsuite/btcwallet/wallet/txauthor v1.3.4
 	github.com/btcsuite/btcwallet/wallet/txrules v1.2.1
+	github.com/btcsuite/btcwallet/wallet/txsizes v1.2.4
 	github.com/btcsuite/btcwallet/walletdb v1.4.2
 	github.com/btcsuite/btcwallet/wtxmgr v1.5.3
 	github.com/coreos/go-systemd v0.0.0-20190719114852-fd7a80b32e1f
@@ -72,7 +73,6 @@ require (
 	github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da // indirect
 	github.com/aead/siphash v1.0.1 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
-	github.com/btcsuite/btcwallet/wallet/txsizes v1.2.4 // indirect
 	github.com/btcsuite/go-socks v0.0.0-20170105172521-4720035b7bfd // indirect
 	github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792 // indirect
 	github.com/btcsuite/winsvc v1.0.0 // indirect

itest/list_on_test.go

@@ -630,4 +630,8 @@ var allTestCases = []*lntest.TestCase{
 		Name:     "coop close with external delivery",
 		TestFunc: testCoopCloseWithExternalDelivery,
 	},
+	{
+		Name:     "send coins with select utxos",
+		TestFunc: testSendCoinSelectUtxo,
+	},
 }