multi: add coin selection strategy option to all on-chain rpcs

In this commit, we add the coin selection strategy option to the following
on-chain RPCs `fundpsbt`, `batchopenchannel`, `estimatefee`, `sendcoins`,
`sendmany`, and `sendoutputs`.

funding/batch.go

@@ -343,6 +343,7 @@ func (b *Batcher) BatchFund(ctx context.Context,
 		MinConfs:              firstReq.MinConfs,
 		SpendUnconfirmed:      firstReq.MinConfs == 0,
 		ChangeType:            changeType,
+		CoinSelectionStrategy: req.CoinSelectionStrategy,
 	}
 	fundPsbtResp, err := b.cfg.WalletKitServer.FundPsbt(ctx, fundPsbtReq)
 	if err != nil {

lnrpc/walletrpc/walletkit_server.go

@@ -799,12 +799,19 @@ func (w *WalletKit) SendOutputs(ctx context.Context,
 		return nil, err
 	}
 
+	coinSelectionStrategy, err := lnrpc.UnmarshallCoinSelectionStrategy(
+		req.CoinSelectionStrategy, w.cfg.CoinSelectionStrategy,
+	)
+	if err != nil {
+		return nil, err
+	}
+
 	// Now that we have the outputs mapped and checked for the reserve
 	// requirement, we can request that the wallet attempts to create this
 	// transaction.
 	tx, err := w.cfg.Wallet.SendOutputs(
 		outputsToCreate, chainfee.SatPerKWeight(req.SatPerKw), minConfs,
-		label,
+		label, coinSelectionStrategy,
 	)
 	if err != nil {
 		return nil, err
@@ -1173,12 +1180,15 @@ func (w *WalletKit) LabelTransaction(ctx context.Context,
 func (w *WalletKit) FundPsbt(_ context.Context,
 	req *FundPsbtRequest) (*FundPsbtResponse, error) {
 
-	var (
-		err         error
-		feeSatPerKW chainfee.SatPerKWeight
+	coinSelectionStrategy, err := lnrpc.UnmarshallCoinSelectionStrategy(
+		req.CoinSelectionStrategy, w.cfg.CoinSelectionStrategy,
 	)
+	if err != nil {
+		return nil, err
+	}
 
 	// Determine the desired transaction fee.
+	var feeSatPerKW chainfee.SatPerKWeight
 	switch {
 	// Estimate the fee by the target number of blocks to confirmation.
 	case req.GetTargetConf() != 0:
@@ -1241,7 +1251,7 @@ func (w *WalletKit) FundPsbt(_ context.Context,
 		// wallet.
 		return w.fundPsbtInternalWallet(
 			account, keyScopeFromChangeAddressType(req.ChangeType),
-			packet, minConfs, feeSatPerKW,
+			packet, minConfs, feeSatPerKW, coinSelectionStrategy,
 		)
 
 	// The template is specified as a PSBT with the intention to perform
@@ -1317,7 +1327,7 @@ func (w *WalletKit) FundPsbt(_ context.Context,
 		// coin selection algorithm.
 		return w.fundPsbtCoinSelect(
 			account, changeIndex, packet, minConfs, changeType,
-			feeSatPerKW,
+			feeSatPerKW, coinSelectionStrategy,
 		)
 
 	// The template is specified as a RPC message. We need to create a new
@@ -1374,7 +1384,7 @@ func (w *WalletKit) FundPsbt(_ context.Context,
 		// wallet.
 		return w.fundPsbtInternalWallet(
 			account, keyScopeFromChangeAddressType(req.ChangeType),
-			packet, minConfs, feeSatPerKW,
+			packet, minConfs, feeSatPerKW, coinSelectionStrategy,
 		)
 
 	default:
@@ -1387,7 +1397,8 @@ func (w *WalletKit) FundPsbt(_ context.Context,
 // wallet that does not allow specifying custom inputs while selecting coins.
 func (w *WalletKit) fundPsbtInternalWallet(account string,
 	keyScope *waddrmgr.KeyScope, packet *psbt.Packet, minConfs int32,
-	feeSatPerKW chainfee.SatPerKWeight) (*FundPsbtResponse, error) {
+	feeSatPerKW chainfee.SatPerKWeight,
+	strategy base.CoinSelectionStrategy) (*FundPsbtResponse, error) {
 
 	// The RPC parsing part is now over. Several of the following operations
 	// require us to hold the global coin selection lock, so we do the rest
@@ -1419,7 +1430,8 @@ func (w *WalletKit) fundPsbtInternalWallet(account string,
 		// lock any coins but might still change the wallet DB by
 		// generating a new change address.
 		changeIndex, err := w.cfg.Wallet.FundPsbt(
-			packet, minConfs, feeSatPerKW, account, keyScope,
+			packet, minConfs, feeSatPerKW, account,
+			keyScope, strategy,
 		)
 		if err != nil {
 			return fmt.Errorf("wallet couldn't fund PSBT: %w", err)
@@ -1454,10 +1466,13 @@ func (w *WalletKit) fundPsbtInternalWallet(account string,
 // fundPsbtCoinSelect uses the "new" PSBT funding method using the channel
 // funding coin selection algorithm that allows specifying custom inputs while
 // selecting coins.
+//
+//nolint:funlen
 func (w *WalletKit) fundPsbtCoinSelect(account string, changeIndex int32,
 	packet *psbt.Packet, minConfs int32,
 	changeType chanfunding.ChangeAddressType,
-	feeRate chainfee.SatPerKWeight) (*FundPsbtResponse, error) {
+	feeRate chainfee.SatPerKWeight, strategy base.CoinSelectionStrategy) (
+	*FundPsbtResponse, error) {
 
 	// We want to make sure we don't select any inputs that are already
 	// specified in the template. To do that, we require those inputs to
@@ -1603,7 +1618,7 @@ func (w *WalletKit) fundPsbtCoinSelect(account string, changeIndex int32,
 
 		selectedCoins, changeAmount, err := chanfunding.CoinSelect(
 			feeRate, fundingAmount, changeDustLimit, coins,
-			w.cfg.CoinSelectionStrategy, estimator, changeType,
+			strategy, estimator, changeType,
 		)
 		if err != nil {
 			return fmt.Errorf("error selecting coins: %w", err)

lnrpc/walletrpc/walletkit_server_test.go

@@ -574,6 +574,7 @@ func TestFundPsbtCoinSelect(t *testing.T) {
 			resp, err := rpcServer.fundPsbtCoinSelect(
 				"", tc.changeIndex, copiedPacket, 0,
 				tc.changeType, tc.feeRate,
+				rpcServer.cfg.CoinSelectionStrategy,
 			)
 
 			switch {

lntest/mock/walletcontroller.go

@@ -141,14 +141,16 @@ func (w *WalletController) ImportTaprootScript(waddrmgr.KeyScope,
 
 // SendOutputs currently returns dummy values.
 func (w *WalletController) SendOutputs([]*wire.TxOut,
-	chainfee.SatPerKWeight, int32, string) (*wire.MsgTx, error) {
+	chainfee.SatPerKWeight, int32, string,
+	base.CoinSelectionStrategy) (*wire.MsgTx, error) {
 
 	return nil, nil
 }
 
 // CreateSimpleTx currently returns dummy values.
 func (w *WalletController) CreateSimpleTx([]*wire.TxOut,
-	chainfee.SatPerKWeight, int32, bool) (*txauthor.AuthoredTx, error) {
+	chainfee.SatPerKWeight, int32, base.CoinSelectionStrategy,
+	bool) (*txauthor.AuthoredTx, error) {
 
 	return nil, nil
 }
@@ -206,7 +208,7 @@ func (w *WalletController) ListLeasedOutputs() ([]*base.ListLeasedOutputResult,
 
 // FundPsbt currently does nothing.
 func (w *WalletController) FundPsbt(*psbt.Packet, int32, chainfee.SatPerKWeight,
-	string, *waddrmgr.KeyScope) (int32, error) {
+	string, *waddrmgr.KeyScope, base.CoinSelectionStrategy) (int32, error) {
 
 	return 0, nil
 }

lnwallet/btcwallet/btcwallet.go

@@ -978,8 +978,8 @@ func (b *BtcWallet) ImportTaprootScript(scope waddrmgr.KeyScope,
 //
 // This is a part of the WalletController interface.
 func (b *BtcWallet) SendOutputs(outputs []*wire.TxOut,
-	feeRate chainfee.SatPerKWeight, minConfs int32,
-	label string) (*wire.MsgTx, error) {
+	feeRate chainfee.SatPerKWeight, minConfs int32, label string,
+	strategy base.CoinSelectionStrategy) (*wire.MsgTx, error) {
 
 	// Convert our fee rate from sat/kw to sat/kb since it's required by
 	// SendOutputs.
@@ -997,7 +997,7 @@ func (b *BtcWallet) SendOutputs(outputs []*wire.TxOut,
 
 	return b.wallet.SendOutputs(
 		outputs, nil, defaultAccount, minConfs, feeSatPerKB,
-		b.cfg.CoinSelectionStrategy, label,
+		strategy, label,
 	)
 }
 
@@ -1016,6 +1016,7 @@ func (b *BtcWallet) SendOutputs(outputs []*wire.TxOut,
 // This is a part of the WalletController interface.
 func (b *BtcWallet) CreateSimpleTx(outputs []*wire.TxOut,
 	feeRate chainfee.SatPerKWeight, minConfs int32,
+	strategy base.CoinSelectionStrategy,
 	dryRun bool) (*txauthor.AuthoredTx, error) {
 
 	// The fee rate is passed in using units of sat/kw, so we'll convert
@@ -1048,7 +1049,7 @@ func (b *BtcWallet) CreateSimpleTx(outputs []*wire.TxOut,
 
 	return b.wallet.CreateSimpleTx(
 		nil, defaultAccount, outputs, minConfs, feeSatPerKB,
-		b.cfg.CoinSelectionStrategy, dryRun,
+		strategy, dryRun,
 	)
 }
 

lnwallet/btcwallet/psbt.go

@@ -73,7 +73,8 @@ var (
 // This is a part of the WalletController interface.
 func (b *BtcWallet) FundPsbt(packet *psbt.Packet, minConfs int32,
 	feeRate chainfee.SatPerKWeight, accountName string,
-	changeScope *waddrmgr.KeyScope) (int32, error) {
+	changeScope *waddrmgr.KeyScope,
+	strategy wallet.CoinSelectionStrategy) (int32, error) {
 
 	// The fee rate is passed in using units of sat/kw, so we'll convert
 	// this to sat/KB as the CreateSimpleTx method requires this unit.
@@ -134,7 +135,7 @@ func (b *BtcWallet) FundPsbt(packet *psbt.Packet, minConfs int32,
 	// the partial TX information in the packet.
 	return b.wallet.FundPsbt(
 		packet, keyScope, minConfs, accountNum, feeSatPerKB,
-		b.cfg.CoinSelectionStrategy, opts...,
+		strategy, opts...,
 	)
 }
 

lnwallet/interface.go

@@ -345,7 +345,8 @@ type WalletController interface {
 	//
 	// NOTE: This method requires the global coin selection lock to be held.
 	SendOutputs(outputs []*wire.TxOut, feeRate chainfee.SatPerKWeight,
-		minConfs int32, label string) (*wire.MsgTx, error)
+		minConfs int32, label string,
+		strategy base.CoinSelectionStrategy) (*wire.MsgTx, error)
 
 	// CreateSimpleTx creates a Bitcoin transaction paying to the specified
 	// outputs. The transaction is not broadcasted to the network. In the
@@ -360,7 +361,8 @@ type WalletController interface {
 	//
 	// NOTE: This method requires the global coin selection lock to be held.
 	CreateSimpleTx(outputs []*wire.TxOut, feeRate chainfee.SatPerKWeight,
-		minConfs int32, dryRun bool) (*txauthor.AuthoredTx, error)
+		minConfs int32, strategy base.CoinSelectionStrategy,
+		dryRun bool) (*txauthor.AuthoredTx, error)
 
 	// GetTransactionDetails returns a detailed description of a transaction
 	// given its transaction hash.
@@ -465,7 +467,8 @@ type WalletController interface {
 	// to lock the inputs before handing them out.
 	FundPsbt(packet *psbt.Packet, minConfs int32,
 		feeRate chainfee.SatPerKWeight, account string,
-		changeScope *waddrmgr.KeyScope) (int32, error)
+		changeScope *waddrmgr.KeyScope,
+		strategy base.CoinSelectionStrategy) (int32, error)
 
 	// SignPsbt expects a partial transaction with all inputs and outputs
 	// fully declared and tries to sign all unsigned inputs that have all

lnwallet/mock.go

@@ -146,14 +146,16 @@ func (w *mockWalletController) ImportTaprootScript(waddrmgr.KeyScope,
 
 // SendOutputs currently returns dummy values.
 func (w *mockWalletController) SendOutputs([]*wire.TxOut,
-	chainfee.SatPerKWeight, int32, string) (*wire.MsgTx, error) {
+	chainfee.SatPerKWeight, int32, string,
+	base.CoinSelectionStrategy) (*wire.MsgTx, error) {
 
 	return nil, nil
 }
 
 // CreateSimpleTx currently returns dummy values.
 func (w *mockWalletController) CreateSimpleTx([]*wire.TxOut,
-	chainfee.SatPerKWeight, int32, bool) (*txauthor.AuthoredTx, error) {
+	chainfee.SatPerKWeight, int32, base.CoinSelectionStrategy,
+	bool) (*txauthor.AuthoredTx, error) {
 
 	return nil, nil
 }
@@ -214,7 +216,8 @@ func (w *mockWalletController) ListLeasedOutputs() (
 
 // FundPsbt currently does nothing.
 func (w *mockWalletController) FundPsbt(*psbt.Packet, int32,
-	chainfee.SatPerKWeight, string, *waddrmgr.KeyScope) (int32, error) {
+	chainfee.SatPerKWeight, string, *waddrmgr.KeyScope,
+	base.CoinSelectionStrategy) (int32, error) {
 
 	return 0, nil
 }

lnwallet/rpcwallet/rpcwallet.go

@@ -121,11 +121,11 @@ func (r *RPCKeyRing) NewAddress(addrType lnwallet.AddressType, change bool,
 //
 // NOTE: This method only signs with BIP49/84 keys.
 func (r *RPCKeyRing) SendOutputs(outputs []*wire.TxOut,
-	feeRate chainfee.SatPerKWeight, minConfs int32,
-	label string) (*wire.MsgTx, error) {
+	feeRate chainfee.SatPerKWeight, minConfs int32, label string,
+	strategy basewallet.CoinSelectionStrategy) (*wire.MsgTx, error) {
 
 	tx, err := r.WalletController.SendOutputs(
-		outputs, feeRate, minConfs, label,
+		outputs, feeRate, minConfs, label, strategy,
 	)
 	if err != nil && err != basewallet.ErrTxUnsigned {
 		return nil, err

lnwallet/test/test_interface.go

@@ -170,6 +170,7 @@ func sendCoins(t *testing.T, miner *rpctest.Harness,
 
 	tx, err := sender.SendOutputs(
 		[]*wire.TxOut{output}, feeRate, minConf, labels.External,
+		sender.Cfg.CoinSelectionStrategy,
 	)
 	require.NoError(t, err, "unable to send transaction")
 
@@ -1189,6 +1190,7 @@ func testListTransactionDetails(miner *rpctest.Harness,
 	burnOutput := wire.NewTxOut(outputAmt, outputScript)
 	burnTX, err := alice.SendOutputs(
 		[]*wire.TxOut{burnOutput}, 2500, 1, labels.External,
+		alice.Cfg.CoinSelectionStrategy,
 	)
 	require.NoError(t, err, "unable to create burn tx")
 	burnTXID := burnTX.TxHash()
@@ -1448,6 +1450,7 @@ func testTransactionSubscriptions(miner *rpctest.Harness,
 	burnOutput := wire.NewTxOut(outputAmt, outputScript)
 	tx, err := alice.SendOutputs(
 		[]*wire.TxOut{burnOutput}, 2500, 1, labels.External,
+		alice.Cfg.CoinSelectionStrategy,
 	)
 	require.NoError(t, err, "unable to create tx")
 	txid := tx.TxHash()
@@ -1636,6 +1639,7 @@ func newTx(t *testing.T, r *rpctest.Harness, pubKey *btcec.PublicKey,
 	}
 	tx, err := alice.SendOutputs(
 		[]*wire.TxOut{newOutput}, 2500, 1, labels.External,
+		alice.Cfg.CoinSelectionStrategy,
 	)
 	require.NoError(t, err, "unable to create output")
 
@@ -1951,6 +1955,7 @@ func testSignOutputUsingTweaks(r *rpctest.Harness,
 		}
 		tx, err := alice.SendOutputs(
 			[]*wire.TxOut{newOutput}, 2500, 1, labels.External,
+			alice.Cfg.CoinSelectionStrategy,
 		)
 		if err != nil {
 			t.Fatalf("unable to create output: %v", err)
@@ -2069,6 +2074,7 @@ func testReorgWalletBalance(r *rpctest.Harness, w *lnwallet.LightningWallet,
 	}
 	tx, err := w.SendOutputs(
 		[]*wire.TxOut{output}, 2500, 1, labels.External,
+		w.Cfg.CoinSelectionStrategy,
 	)
 	require.NoError(t, err, "unable to send outputs")
 	txid := tx.TxHash()
@@ -2293,6 +2299,7 @@ func testSpendUnconfirmed(miner *rpctest.Harness,
 	}
 	_, err = bob.SendOutputs(
 		[]*wire.TxOut{output}, txFeeRate, 0, labels.External,
+		bob.Cfg.CoinSelectionStrategy,
 	)
 	if err == nil {
 		t.Fatalf("should have not been able to pay due to insufficient balance: %v", err)
@@ -2319,6 +2326,7 @@ func testSpendUnconfirmed(miner *rpctest.Harness,
 	// using confirmed outputs only.
 	_, err = bob.SendOutputs(
 		[]*wire.TxOut{output}, txFeeRate, 1, labels.External,
+		bob.Cfg.CoinSelectionStrategy,
 	)
 	if err == nil {
 		t.Fatalf("should have not been able to pay due to insufficient balance: %v", err)
@@ -2559,7 +2567,8 @@ func testCreateSimpleTx(r *rpctest.Harness, w *lnwallet.LightningWallet,
 
 		// Now try creating a tx spending to these outputs.
 		createTx, createErr := w.CreateSimpleTx(
-			outputs, feeRate, minConfs, true,
+			outputs, feeRate, minConfs,
+			w.Cfg.CoinSelectionStrategy, true,
 		)
 		switch {
 		case test.valid && createErr != nil:
@@ -2578,6 +2587,7 @@ func testCreateSimpleTx(r *rpctest.Harness, w *lnwallet.LightningWallet,
 		// that the change output position might be different.
 		tx, sendErr := w.SendOutputs(
 			outputs, feeRate, minConfs, labels.External,
+			w.Cfg.CoinSelectionStrategy,
 		)
 		switch {
 		case test.valid && sendErr != nil:

rpcserver.go

@@ -30,6 +30,7 @@ import (
 	"github.com/btcsuite/btcd/txscript"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcwallet/waddrmgr"
+	"github.com/btcsuite/btcwallet/wallet"
 	"github.com/btcsuite/btcwallet/wallet/txauthor"
 	"github.com/davecgh/go-spew/spew"
 	proxy "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
@@ -1067,8 +1068,8 @@ func allowCORS(handler http.Handler, origins []string) http.Handler {
 // more addresses specified in the passed payment map. The payment map maps an
 // address to a specified output value to be sent to that address.
 func (r *rpcServer) sendCoinsOnChain(paymentMap map[string]int64,
-	feeRate chainfee.SatPerKWeight, minConfs int32,
-	label string) (*chainhash.Hash, error) {
+	feeRate chainfee.SatPerKWeight, minConfs int32, label string,
+	strategy wallet.CoinSelectionStrategy) (*chainhash.Hash, error) {
 
 	outputs, err := addrPairsToOutputs(paymentMap, r.cfg.ActiveNetParams.Params)
 	if err != nil {
@@ -1078,7 +1079,7 @@ func (r *rpcServer) sendCoinsOnChain(paymentMap map[string]int64,
 	// We first do a dry run, to sanity check we won't spend our wallet
 	// balance below the reserved amount.
 	authoredTx, err := r.server.cc.Wallet.CreateSimpleTx(
-		outputs, feeRate, minConfs, true,
+		outputs, feeRate, minConfs, strategy, true,
 	)
 	if err != nil {
 		return nil, err
@@ -1099,7 +1100,7 @@ func (r *rpcServer) sendCoinsOnChain(paymentMap map[string]int64,
 	// If that checks out, we're fairly confident that creating sending to
 	// these outputs will keep the wallet balance above the reserve.
 	tx, err := r.server.cc.Wallet.SendOutputs(
-		outputs, feeRate, minConfs, label,
+		outputs, feeRate, minConfs, label, strategy,
 	)
 	if err != nil {
 		return nil, err
@@ -1192,12 +1193,23 @@ func (r *rpcServer) EstimateFee(ctx context.Context,
 		return nil, err
 	}
 
+	coinSelectionStrategy, err := lnrpc.UnmarshallCoinSelectionStrategy(
+		in.CoinSelectionStrategy,
+		r.server.cc.Wallet.Cfg.CoinSelectionStrategy,
+	)
+	if err != nil {
+		return nil, err
+	}
+
 	// 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(outputs, feePerKw, minConfs, true)
+		tx, err = wallet.CreateSimpleTx(
+			outputs, feePerKw, minConfs, coinSelectionStrategy,
+			true,
+		)
 		return err
 	})
 	if err != nil {
@@ -1281,6 +1293,14 @@ func (r *rpcServer) SendCoins(ctx context.Context,
 		return nil, err
 	}
 
+	coinSelectionStrategy, err := lnrpc.UnmarshallCoinSelectionStrategy(
+		in.CoinSelectionStrategy,
+		r.server.cc.Wallet.Cfg.CoinSelectionStrategy,
+	)
+	if err != nil {
+		return nil, err
+	}
+
 	var txid *chainhash.Hash
 
 	wallet := r.server.cc.Wallet
@@ -1417,7 +1437,8 @@ func (r *rpcServer) SendCoins(ctx context.Context,
 		paymentMap := map[string]int64{targetAddr.String(): in.Amount}
 		err := wallet.WithCoinSelectLock(func() error {
 			newTXID, err := r.sendCoinsOnChain(
-				paymentMap, feePerKw, minConfs, label,
+				paymentMap, feePerKw, minConfs,
+				label, coinSelectionStrategy,
 			)
 			if err != nil {
 				return err
@@ -1463,6 +1484,14 @@ func (r *rpcServer) SendMany(ctx context.Context,
 		return nil, err
 	}
 
+	coinSelectionStrategy, err := lnrpc.UnmarshallCoinSelectionStrategy(
+		in.CoinSelectionStrategy,
+		r.server.cc.Wallet.Cfg.CoinSelectionStrategy,
+	)
+	if err != nil {
+		return nil, err
+	}
+
 	rpcsLog.Infof("[sendmany] outputs=%v, sat/kw=%v",
 		spew.Sdump(in.AddrToAmount), int64(feePerKw))
 
@@ -1474,7 +1503,8 @@ func (r *rpcServer) SendMany(ctx context.Context,
 	wallet := r.server.cc.Wallet
 	err = wallet.WithCoinSelectLock(func() error {
 		sendManyTXID, err := r.sendCoinsOnChain(
-			in.AddrToAmount, feePerKw, minConfs, label,
+			in.AddrToAmount, feePerKw, minConfs,
+			label, coinSelectionStrategy,
 		)
 		if err != nil {
 			return err