asset{btc/ltc}: Add custom wallet constructor for BTC and LTC

client/asset/bch/spv.go

@@ -52,10 +52,11 @@ import (
 )
 
 const (
-	DefaultM       uint64 = 784931 // From bchutil. Used for gcs filters.
-	logDirName            = "logs"
-	neutrinoDBName        = "neutrino.db"
-	defaultAcctNum        = 0
+	DefaultM        uint64 = 784931 // From bchutil. Used for gcs filters.
+	logDirName             = "logs"
+	neutrinoDBName         = "neutrino.db"
+	defaultAcctNum         = 0
+	defaultAcctName        = "default"
 )
 
 var (
@@ -270,6 +271,15 @@ func (w *bchSPVWallet) txDetails(txHash *bchchainhash.Hash) (*bchwtxmgr.TxDetail
 
 var _ btc.BTCWallet = (*bchSPVWallet)(nil)
 
+// AccountInfo returns the account information of the wallet for use by the
+// exchange wallet.
+func (w *bchSPVWallet) AccountInfo() btc.XCWalletAccount {
+	return btc.XCWalletAccount{
+		AccountName:   defaultAcctName,
+		AccountNumber: defaultAcctNum,
+	}
+}
+
 func (w *bchSPVWallet) PublishTransaction(btcTx *wire.MsgTx, label string) error {
 	bchTx, err := convertMsgTxToBCH(btcTx)
 	if err != nil {

client/asset/btc/btc.go

@@ -654,6 +654,29 @@ func (d *Driver) Info() *asset.WalletInfo {
 	return WalletInfo
 }
 
+type CustomSPVWalletConstructor func(settings map[string]string, params *chaincfg.Params) (BTCWallet, error)
+
+// customSPVWalletConstructors are functions for setting up custom
+// implementations of the BTCWallet interface that may be used by the
+// ExchangeWalletSPV instead of the default spv implementation.
+var customSPVWalletConstructors = map[string]CustomSPVWalletConstructor{}
+
+// RegisterCustomSPVWallet registers a function that should be used in creating
+// a BTCWallet implementation that the ExchangeWalletSPV will use in place of
+// the default spv wallet implementation. External consumers can use this
+// function to provide alternative BTCWallet implementations, and must do so
+// before attempting to create an ExchangeWalletSPV instance of this type. It'll
+// panic if callers try to register a wallet twice.
+func RegisterCustomSPVWallet(constructor CustomSPVWalletConstructor, def *asset.WalletDefinition) {
+	for _, availableWallets := range WalletInfo.AvailableWallets {
+		if def.Type == availableWallets.Type {
+			panic(fmt.Sprintf("wallet type (%q) is already registered", def.Type))
+		}
+	}
+	customSPVWalletConstructors[def.Type] = constructor
+	WalletInfo.AvailableWallets = append(WalletInfo.AvailableWallets, def)
+}
+
 // swapOptions captures the available Swap options. Tagged to be used with
 // config.Unmapify to decode e.g. asset.Order.Options.
 type swapOptions struct {
@@ -1001,7 +1024,22 @@ func NewWallet(cfg *asset.WalletConfig, logger dex.Logger, net dex.Network) (ass
 		cloneCFG.Ports = dexbtc.NetPorts{} // no default ports
 		return ElectrumWallet(cloneCFG)
 	default:
-		return nil, fmt.Errorf("unknown wallet type %q", cfg.Type)
+		makeCustomWallet, ok := customSPVWalletConstructors[cfg.Type]
+		if !ok {
+			return nil, fmt.Errorf("unknown wallet type %q", cfg.Type)
+		}
+
+		// Create custom wallet first and return early if we encounter any
+		// error.
+		btcWallet, err := makeCustomWallet(cfg.Settings, cloneCFG.ChainParams)
+		if err != nil {
+			return nil, fmt.Errorf("btc custom wallet setup error: %v", err)
+		}
+
+		walletConstructor := func(_ string, _ *WalletConfig, _ *chaincfg.Params, _ dex.Logger) BTCWallet {
+			return btcWallet
+		}
+		return OpenSPVWallet(cloneCFG, walletConstructor)
 	}
 }
 
@@ -1258,8 +1296,6 @@ func OpenSPVWallet(cfg *BTCCloneCFG, walletConstructor BTCWalletConstructor) (*E
 	spvw := &spvWallet{
 		chainParams: cfg.ChainParams,
 		cfg:         walletCfg,
-		acctNum:     defaultAcctNum,
-		acctName:    defaultAcctName,
 		dir:         filepath.Join(cfg.WalletCFG.DataDir, cfg.ChainParams.Name),
 		txBlocks:    make(map[chainhash.Hash]*hashEntry),
 		checkpoints: make(map[OutPoint]*scanCheckpoint),
@@ -1271,6 +1307,9 @@ func OpenSPVWallet(cfg *BTCCloneCFG, walletConstructor BTCWalletConstructor) (*E
 	spvw.wallet = walletConstructor(spvw.dir, spvw.cfg, spvw.chainParams, spvw.log)
 	btc.setNode(spvw)
 
+	// Set account number for easy reference.
+	spvw.acctNum = spvw.wallet.AccountInfo().AccountNumber
+
 	w := &ExchangeWalletSPV{
 		intermediaryWallet: &intermediaryWallet{
 			baseWallet:     btc,

client/asset/btc/spv.go

@@ -121,6 +121,15 @@ func openSPVWallet(dir string, cfg *WalletConfig,
 	return w
 }
 
+// AccountInfo returns the account information of the wallet for use by the
+// exchange wallet.
+func (w *btcSPVWallet) AccountInfo() XCWalletAccount {
+	return XCWalletAccount{
+		AccountName:   defaultAcctName,
+		AccountNumber: defaultAcctNum,
+	}
+}
+
 func (w *btcSPVWallet) Birthday() time.Time {
 	return w.birthdayV.Load().(time.Time)
 }

client/asset/btc/spv_test.go

@@ -39,6 +39,13 @@ type tBtcWallet struct {
 	*testData
 }
 
+func (c *tBtcWallet) AccountInfo() XCWalletAccount {
+	return XCWalletAccount{
+		AccountName:   defaultAcctName,
+		AccountNumber: defaultAcctNum,
+	}
+}
+
 func (c *tBtcWallet) ListSinceBlock(start, end, syncHeight int32) ([]btcjson.ListTransactionsResult, error) {
 	return nil, nil
 }

client/asset/btc/spv_wrapper.go

@@ -102,6 +102,9 @@ type BTCWallet interface {
 	WaitForShutdown()
 	ChainSynced() bool // currently unused
 	AccountProperties(scope waddrmgr.KeyScope, acct uint32) (*waddrmgr.AccountProperties, error)
+	// AccountInfo returns the account information of the wallet for use by the
+	// exchange wallet.
+	AccountInfo() XCWalletAccount
 	// The below methods are not implemented by *wallet.Wallet, so must be
 	// implemented by the BTCWallet implementation.
 	WalletTransaction(txHash *chainhash.Hash) (*wtxmgr.TxDetails, error)
@@ -120,6 +123,11 @@ type BTCWallet interface {
 	ListSinceBlock(start, end, syncHeight int32) ([]btcjson.ListTransactionsResult, error)
 }
 
+type XCWalletAccount struct {
+	AccountName   string
+	AccountNumber uint32
+}
+
 // BlockNotification is block hash and height delivered by a BTCWallet when it
 // is finished processing a block.
 type BlockNotification struct {
@@ -244,7 +252,6 @@ type spvWallet struct {
 	wallet      BTCWallet
 	cl          SPVService
 	acctNum     uint32
-	acctName    string
 	dir         string
 	decodeAddr  dexbtc.AddressDecoder
 
@@ -607,7 +614,7 @@ func (w *spvWallet) listTransactionsSinceBlock(blockHeight int32) ([]btcjson.Lis
 // balances retrieves a wallet's balance details.
 func (w *spvWallet) balances() (*GetBalancesResult, error) {
 	// Determine trusted vs untrusted coins with listunspent.
-	unspents, err := w.wallet.ListUnspent(0, math.MaxInt32, w.acctName)
+	unspents, err := w.wallet.ListUnspent(0, math.MaxInt32, w.wallet.AccountInfo().AccountName)
 	if err != nil {
 		return nil, fmt.Errorf("error listing unspent outputs: %w", err)
 	}
@@ -644,7 +651,7 @@ func (w *spvWallet) balances() (*GetBalancesResult, error) {
 
 // listUnspent retrieves list of the wallet's UTXOs.
 func (w *spvWallet) listUnspent() ([]*ListUnspentResult, error) {
-	unspents, err := w.wallet.ListUnspent(0, math.MaxInt32, w.acctName)
+	unspents, err := w.wallet.ListUnspent(0, math.MaxInt32, w.wallet.AccountInfo().AccountName)
 	if err != nil {
 		return nil, err
 	}

client/asset/dcr/dcr.go

@@ -744,14 +744,16 @@ func NewWallet(cfg *asset.WalletConfig, logger dex.Logger, network dex.Network)
 			return nil, err
 		}
 	default:
-		if makeCustomWallet, ok := customWalletConstructors[cfg.Type]; ok {
-			dcr.wallet, err = makeCustomWallet(cfg.Settings, chainParams, logger)
-			if err != nil {
-				return nil, fmt.Errorf("custom wallet setup error: %v", err)
-			}
-		} else {
+		makeCustomWallet, ok := customWalletConstructors[cfg.Type]
+		if !ok {
 			return nil, fmt.Errorf("unknown wallet type %q", cfg.Type)
 		}
+
+		// Create custom wallet and return early if we encounter any error.
+		dcr.wallet, err = makeCustomWallet(cfg.Settings, chainParams, logger)
+		if err != nil {
+			return nil, fmt.Errorf("custom wallet setup error: %v", err)
+		}
 	}
 
 	return w, nil

client/asset/dcr/wallet.go

@@ -33,16 +33,16 @@ var customWalletConstructors = map[string]WalletConstructor{}
 // Wallet implementation that the ExchangeWallet of the specified type will use
 // in place of the default rpcWallet implementation. External consumers can use
 // this function to provide alternative Wallet implementations, and must do so
-// before attempting to create an ExchangeWallet instance of this type.
-func RegisterCustomWallet(constructor WalletConstructor, def *asset.WalletDefinition) error {
+// before attempting to create an ExchangeWallet instance of this type. It'll
+// panic if callers try to register a wallet twice.
+func RegisterCustomWallet(constructor WalletConstructor, def *asset.WalletDefinition) {
 	for _, availableWallets := range WalletInfo.AvailableWallets {
 		if def.Type == availableWallets.Type {
-			return fmt.Errorf("already support %q wallets", def.Type)
+			panic(fmt.Sprintf("wallet type (%q) already registered", def.Type))
 		}
 	}
 	customWalletConstructors[def.Type] = constructor
 	WalletInfo.AvailableWallets = append(WalletInfo.AvailableWallets, def)
-	return nil
 }
 
 type TipChangeCallback func(context.Context, *chainhash.Hash, int64, error)

client/asset/interface.go

@@ -378,7 +378,7 @@ type WalletConfig struct {
 	// wallet/node peers changes, or the wallet fails to get the count. This
 	// should not be called prior to Connect of the constructed wallet.
 	PeersChange func(uint32, error)
-	// DataDir is a filesystem directory the the wallet may use for persistent
+	// DataDir is a filesystem directory the wallet may use for persistent
 	// storage.
 	DataDir string
 }

client/asset/ltc/ltc.go

@@ -158,6 +158,27 @@ func (d *Driver) Create(params *asset.CreateWalletParams) error {
 		params.Logger, recoveryCfg.NumExternalAddresses, recoveryCfg.NumInternalAddresses, chainParams)
 }
 
+// customSPVWalletConstructors are functions for setting up custom
+// implementations of the btc.BTCWallet interface that may be used by the
+// ExchangeWalletSPV instead of the default spv implementation.
+var customSPVWalletConstructors = map[string]btc.CustomSPVWalletConstructor{}
+
+// RegisterCustomSPVWallet registers a function that should be used in creating
+// a btc.BTCWallet implementation that the ExchangeWalletSPV will use in place
+// of the default spv wallet implementation. External consumers can use this
+// function to provide alternative btc.BTCWallet implementations, and must do so
+// before attempting to create an ExchangeWalletSPV instance of this type. It'll
+// panic if callers try to register a wallet twice.
+func RegisterCustomSPVWallet(constructor btc.CustomSPVWalletConstructor, def *asset.WalletDefinition) {
+	for _, availableWallets := range WalletInfo.AvailableWallets {
+		if def.Type == availableWallets.Type {
+			panic(fmt.Sprintf("wallet type (%q) is already registered", def.Type))
+		}
+	}
+	customSPVWalletConstructors[def.Type] = constructor
+	WalletInfo.AvailableWallets = append(WalletInfo.AvailableWallets, def)
+}
+
 // NewWallet is the exported constructor by which the DEX will import the
 // exchange wallet.
 func NewWallet(cfg *asset.WalletConfig, logger dex.Logger, network dex.Network) (asset.Wallet, error) {
@@ -204,7 +225,22 @@ func NewWallet(cfg *asset.WalletConfig, logger dex.Logger, network dex.Network)
 		cloneCFG.Ports = dexbtc.NetPorts{} // no default ports
 		return btc.ElectrumWallet(cloneCFG)
 	default:
-		return nil, fmt.Errorf("unknown wallet type %q", cfg.Type)
+		makeCustomWallet, ok := customSPVWalletConstructors[cfg.Type]
+		if !ok {
+			return nil, fmt.Errorf("unknown wallet type %q", cfg.Type)
+		}
+
+		// Create custom wallet first and return early if we encounter any
+		// error.
+		ltcWallet, err := makeCustomWallet(cfg.Settings, cloneCFG.ChainParams)
+		if err != nil {
+			return nil, fmt.Errorf("custom wallet setup error: %v", err)
+		}
+
+		walletConstructor := func(_ string, _ *btc.WalletConfig, _ *chaincfg.Params, _ dex.Logger) btc.BTCWallet {
+			return ltcWallet
+		}
+		return btc.OpenSPVWallet(cloneCFG, walletConstructor)
 	}
 }
 

client/asset/ltc/spv.go

@@ -52,11 +52,12 @@ import (
 )
 
 const (
-	DefaultM       uint64 = 784931 // From ltcutil. Used for gcs filters.
-	logDirName            = "logs"
-	neutrinoDBName        = "neutrino.db"
-	defaultAcctNum        = 0
-	dbTimeout             = 20 * time.Second
+	DefaultM        uint64 = 784931 // From ltcutil. Used for gcs filters.
+	logDirName             = "logs"
+	neutrinoDBName         = "neutrino.db"
+	defaultAcctNum         = 0
+	defaultAcctName        = "default"
+	dbTimeout              = 20 * time.Second
 )
 
 var (
@@ -164,6 +165,15 @@ func createSPVWallet(privPass []byte, seed []byte, bday time.Time, walletDir str
 	return nil
 }
 
+// AccountInfo returns the account information of the wallet for use by the
+// exchange wallet.
+func (w *ltcSPVWallet) AccountInfo() btc.XCWalletAccount {
+	return btc.XCWalletAccount{
+		AccountName:   defaultAcctName,
+		AccountNumber: defaultAcctNum,
+	}
+}
+
 // walletParams works around a bug in ltcwallet that doesn't recognize
 // wire.TestNet4 in (*ScopedKeyManager).cloneKeyWithVersion which is called from
 // AccountProperties. Only do this for the *wallet.Wallet, not the