feature: add DEX seed backup and restore

Signed-off-by: Philemon Ukane <[email protected]>

dexc/core.go

@@ -33,7 +33,7 @@ const (
 type DEXClient struct {
 	ctx      context.Context
 	cancelFn context.CancelFunc
-	DBPath   string
+	dbPath   string
 	*core.Core
 
 	loggedIn        bool
@@ -63,6 +63,10 @@ func (dc *DEXClient) Login(pw []byte) error {
 	return nil
 }
 
+func (dc *DEXClient) DBPath() string {
+	return dc.dbPath
+}
+
 // WaitForShutdown returns a chan that will be closed if core exits.
 func (dc *DEXClient) WaitForShutdown() <-chan struct{} {
 	return dc.shutdownChan
@@ -87,6 +91,10 @@ type valStamp struct {
 func (dc *DEXClient) BondsFeeBuffer(assetID uint32) uint64 {
 	const expiry = 45 * time.Minute
 
+	if !dc.HasWallet(int32(assetID)) { // no configured wallet
+		return 0
+	}
+
 	buf, ok := dc.bondBufferCache.Load(assetID)
 	var cachedFeeBuffer valStamp
 	if ok {
@@ -107,7 +115,7 @@ func (dc *DEXClient) BondsFeeBuffer(assetID uint32) uint64 {
 		default:
 			feeBuffer, err := dc.Core.BondsFeeBuffer(assetID)
 			if err != nil {
-				dc.log.Error("Error fetching bond fee buffer: %v", err)
+				dc.log.Errorf("Error fetching bond fee buffer: %v", err)
 			} else {
 				dc.log.Tracef("Obtained fresh bond fee buffer: %d", feeBuffer)
 				dc.bondBufferCache.Store(assetID, valStamp{feeBuffer, time.Now()})
@@ -150,7 +158,7 @@ func Start(ctx context.Context, root, lang, logDir, logLvl string, net libutils.
 
 	shutdownChan := make(chan struct{})
 	dc := &DEXClient{
-		DBPath:       dbPath,
+		dbPath:       dbPath,
 		Core:         clientCore,
 		shutdownChan: shutdownChan,
 		log:          logger,

libwallet/assets_manager.go

@@ -76,7 +76,8 @@ type AssetsManager struct {
 	RateSource      ext.RateSource
 
 	dexcMtx     sync.RWMutex
-	dexc        *dexc.DEXClient
+	dexcCtx     context.Context
+	dexc        DexClient
 	startingDEX atomic.Bool
 }
 
@@ -904,7 +905,7 @@ func (mgr *AssetsManager) CalculateAssetsUSDBalance(balances map[utils.AssetType
 }
 
 // DexClient returns a dexc client that MUST never be modified.
-func (mgr *AssetsManager) DexClient() *dexc.DEXClient {
+func (mgr *AssetsManager) DexClient() DexClient {
 	mgr.dexcMtx.RLock()
 	defer mgr.dexcMtx.RUnlock()
 	return mgr.dexc
@@ -913,7 +914,8 @@ func (mgr *AssetsManager) DexClient() *dexc.DEXClient {
 func (mgr *AssetsManager) DexcReady() bool {
 	mgr.dexcMtx.RLock()
 	defer mgr.dexcMtx.RUnlock()
-	return mgr.dexc != nil
+	dexClient, _ := mgr.dexc.(*dexc.DEXClient) // check concrete type
+	return dexClient != nil && dexClient.Core != nil
 }
 
 // InitializeDEX initializes mgr.dexc. Support for Cryptopower wallets are
@@ -932,28 +934,22 @@ func (mgr *AssetsManager) InitializeDEX(ctx context.Context) {
 	}
 
 	// Prevent multiple initialization.
+	mgr.dexcCtx = ctx
 	mgr.startingDEX.Store(true)
 	defer func() {
 		mgr.startingDEX.Store(false)
 	}()
 
 	logDir := filepath.Dir(mgr.LogFile())
-	dexcl, err := dexc.Start(ctx, mgr.RootDir(), mgr.GetLanguagePreference(), logDir, mgr.GetLogLevels(), mgr.NetType(), 0 /* TODO: Make configurable */)
+	dexClient, err := dexc.Start(ctx, mgr.RootDir(), mgr.GetLanguagePreference(), logDir, mgr.GetLogLevels(), mgr.NetType(), 0 /* TODO: Make configurable */)
 	if err != nil {
 		log.Errorf("Error starting dex client: %v", err)
 		return
 	}
 
 	mgr.dexcMtx.Lock()
-	mgr.dexc = dexcl
+	mgr.dexc = dexClient
 	mgr.dexcMtx.Unlock()
-
-	go func() {
-		<-mgr.dexc.WaitForShutdown()
-		mgr.dexcMtx.Lock()
-		mgr.dexc = nil
-		mgr.dexcMtx.Unlock()
-	}()
 }
 
 func (mgr *AssetsManager) DeleteDEXData() error {
@@ -965,15 +961,26 @@ func (mgr *AssetsManager) DeleteDEXData() error {
 
 	log.Debug("Shutting down DEX client and removing dex data dir....")
 
-	dexDBFile := mgr.dexc.DBPath
+	dexDBFile := mgr.dexc.DBPath()
 	shutdownChan := mgr.dexc.WaitForShutdown()
 
 	// Shutdown the DEX client.
 	mgr.dexc.Shutdown()
 	<-shutdownChan // wait for shutdown
 
+	mgr.dexcMtx.Lock()
+	mgr.dexc = nil
+	mgr.dexcMtx.Unlock()
+
 	// Delete dex client db.
-	return os.Remove(dexDBFile)
+	err = os.Remove(dexDBFile)
+	if err != nil {
+		return err
+	}
+
+	// Start a new client.
+	mgr.InitializeDEX(mgr.dexcCtx)
+	return nil
 }
 
 // prepareDexSupportForDCRWallet sets up the DEX client to allow using a

libwallet/dex_interface.go

@@ -0,0 +1,36 @@
+package libwallet
+
+import (
+	"decred.org/dcrdex/client/core"
+	"decred.org/dcrdex/client/orderbook"
+	"decred.org/dcrdex/dex"
+)
+
+type DexClient interface {
+	Ready() <-chan struct{}
+	WaitForShutdown() <-chan struct{}
+	Shutdown()
+	IsDEXPasswordSet() bool
+	IsLoggedIn() bool
+	InitWithPassword(pw, seed []byte) error
+	Login(pw []byte) error
+	Logout() error
+	DBPath() string
+	GetDEXConfig(dexAddr string, certI any) (*core.Exchange, error)
+	BondsFeeBuffer(assetID uint32) uint64
+	HasWallet(assetID int32) bool
+	AddWallet(assetID uint32, settings map[string]string, appPW, walletPW []byte) error
+	PostBond(form *core.PostBondForm) (*core.PostBondResult, error)
+	NotificationFeed() *core.NoteFeed
+	Exchanges() map[string]*core.Exchange
+	Exchange(host string) (*core.Exchange, error)
+	ExportSeed(pw []byte) ([]byte, error)
+	SyncBook(dex string, base, quote uint32) (*orderbook.OrderBook, core.BookFeed, error)
+	Orders(filter *core.OrderFilter) ([]*core.Order, error)
+	TradeAsync(pw []byte, form *core.TradeForm) (*core.InFlightOrder, error)
+	WalletState(assetID uint32) *core.WalletState
+	WalletSettings(assetID uint32) (map[string]string, error)
+	MaxBuy(host string, base, quote uint32, rate uint64) (*core.MaxOrderEstimate, error)
+	MaxSell(host string, base, quote uint32) (*core.MaxOrderEstimate, error)
+	Cancel(oid dex.Bytes) error
+}

ui/page/dcrdex/dcrdex_page.go

@@ -85,9 +85,11 @@ func (pg *DEXPage) OnNavigatedTo() {
 
 	pg.dexIsLoading = true
 	go func() {
-		<-pg.AssetsManager.DexClient().Ready()
+		dexc := pg.AssetsManager.DexClient()
+		<-dexc.Ready()
+
 		showOnBoardingPage := true
-		if len(pg.AssetsManager.DexClient().Exchanges()) != 0 { // has at least one exchange
+		if len(dexc.Exchanges()) != 0 { // has at least one exchange
 			_, _, pendingBond := pendingBondConfirmation(pg.AssetsManager)
 			showOnBoardingPage = pendingBond != nil
 		}