multi: add persistent logger

client.go

@@ -192,7 +192,7 @@ func (s *Client) Run(ctx context.Context,
 	if err != nil {
 		return fmt.Errorf("GetInfo error: %v", err)
 	}
-	logger.Infof("Connected to lnd node %v with pubkey %v",
+	log.Infof("Connected to lnd node %v with pubkey %v",
 		info.Alias, hex.EncodeToString(info.IdentityPubkey[:]),
 	)
 
@@ -235,22 +235,22 @@ func (s *Client) Run(ctx context.Context,
 	}
 
 	if err != nil {
-		logger.Errorf("Swap client terminating: %v", err)
+		log.Errorf("Swap client terminating: %v", err)
 	} else {
-		logger.Info("Swap client terminating")
+		log.Info("Swap client terminating")
 	}
 
 	// Cancel all remaining active goroutines.
 	mainCancel()
 
 	// Wait for all to finish.
-	logger.Debug("Wait for executor to finish")
+	log.Debug("Wait for executor to finish")
 	s.executor.waitFinished()
 
-	logger.Debug("Wait for goroutines to finish")
+	log.Debug("Wait for goroutines to finish")
 	s.wg.Wait()
 
-	logger.Info("Swap client terminated")
+	log.Info("Swap client terminated")
 
 	return err
 }
@@ -270,7 +270,7 @@ func (s *Client) resumeSwaps(ctx context.Context,
 		}
 		swap, err := resumeLoopOutSwap(ctx, swapCfg, pend)
 		if err != nil {
-			logger.Errorf("resuming loop out swap: %v", err)
+			log.Errorf("resuming loop out swap: %v", err)
 			continue
 		}
 
@@ -283,7 +283,7 @@ func (s *Client) resumeSwaps(ctx context.Context,
 		}
 		swap, err := resumeLoopInSwap(ctx, swapCfg, pend)
 		if err != nil {
-			logger.Errorf("resuming loop in swap: %v", err)
+			log.Errorf("resuming loop in swap: %v", err)
 			continue
 		}
 
@@ -303,7 +303,7 @@ func (s *Client) resumeSwaps(ctx context.Context,
 func (s *Client) LoopOut(globalCtx context.Context,
 	request *OutRequest) (*lntypes.Hash, btcutil.Address, error) {
 
-	logger.Infof("LoopOut %v to %v (channel: %v)",
+	log.Infof("LoopOut %v to %v (channel: %v)",
 		request.Amount, request.DestAddr,
 		request.LoopOutChannel,
 	)
@@ -358,7 +358,7 @@ func (s *Client) LoopOutQuote(ctx context.Context,
 		return nil, err
 	}
 
-	logger.Infof("Offchain swap destination: %x", quote.SwapPaymentDest)
+	log.Infof("Offchain swap destination: %x", quote.SwapPaymentDest)
 
 	swapFee := quote.SwapFee
 
@@ -418,7 +418,7 @@ func (s *Client) waitForInitialized(ctx context.Context) error {
 func (s *Client) LoopIn(globalCtx context.Context,
 	request *LoopInRequest) (*lntypes.Hash, btcutil.Address, error) {
 
-	logger.Infof("Loop in %v (channel: %v)",
+	log.Infof("Loop in %v (channel: %v)",
 		request.Amount,
 		request.LoopInChannel,
 	)

cmd/loopd/config.go

@@ -1,5 +1,23 @@
 package main
 
+import (
+	"path/filepath"
+
+	"github.com/btcsuite/btcutil"
+)
+
+var (
+	loopDirBase = btcutil.AppDataDir("loop", false)
+
+	defaultLogLevel    = "info"
+	defaultLogDirname  = "logs"
+	defaultLogFilename = "loopd.log"
+	defaultLogDir      = filepath.Join(loopDirBase, defaultLogDirname)
+
+	defaultMaxLogFiles    = 3
+	defaultMaxLogFileSize = 10
+)
+
 type lndConfig struct {
 	Host        string `long:"host" description:"lnd instance rpc address"`
 	MacaroonDir string `long:"macaroondir" description:"Path to the directory containing all the required lnd macaroons"`
@@ -16,6 +34,12 @@ type config struct {
 	RPCListen   string `long:"rpclisten" description:"Address to listen on for gRPC clients"`
 	RESTListen  string `long:"restlisten" description:"Address to listen on for REST clients"`
 
+	LogDir         string `long:"logdir" description:"Directory to log output."`
+	MaxLogFiles    int    `long:"maxlogfiles" description:"Maximum logfiles to keep (0 for no rotation)"`
+	MaxLogFileSize int    `long:"maxlogfilesize" description:"Maximum logfile size in MB"`
+
+	DebugLevel string `short:"d" long:"debuglevel" description:"Logging level for all subsystems {trace, debug, info, warn, error, critical} -- You may also specify <subsystem>=<level>,<subsystem2>=<level>,... to set the log level for individual subsystems -- Use show to list available subsystems"`
+
 	Lnd *lndConfig `group:"lnd" namespace:"lnd"`
 
 	View viewParameters `command:"view" alias:"v" description:"View all swaps in the database. This command can only be executed when loopd is not running."`
@@ -27,10 +51,14 @@ const (
 )
 
 var defaultConfig = config{
-	Network:    "mainnet",
-	RPCListen:  "localhost:11010",
-	RESTListen: "localhost:8081",
-	Insecure:   false,
+	Network:        "mainnet",
+	RPCListen:      "localhost:11010",
+	RESTListen:     "localhost:8081",
+	Insecure:       false,
+	LogDir:         defaultLogDir,
+	MaxLogFiles:    defaultMaxLogFiles,
+	MaxLogFileSize: defaultMaxLogFileSize,
+	DebugLevel:     defaultLogLevel,
 	Lnd: &lndConfig{
 		Host: "localhost:10009",
 	},

cmd/loopd/daemon.go

@@ -40,7 +40,7 @@ func daemon(config *config) error {
 		}
 	}
 
-	logger.Infof("Swap server address: %v", config.SwapServer)
+	log.Infof("Swap server address: %v", config.SwapServer)
 
 	// Create an instance of the loop client library.
 	swapClient, cleanup, err := getClient(
@@ -73,7 +73,7 @@ func daemon(config *config) error {
 	looprpc.RegisterSwapClientServer(grpcServer, &server)
 
 	// Next, start the gRPC server listening for HTTP/2 connections.
-	logger.Infof("Starting gRPC listener")
+	log.Infof("Starting gRPC listener")
 	grpcListener, err := net.Listen("tcp", config.RPCListen)
 	if err != nil {
 		return fmt.Errorf("RPC server unable to listen on %s",
@@ -95,7 +95,7 @@ func daemon(config *config) error {
 		return err
 	}
 
-	logger.Infof("Starting REST proxy listener")
+	log.Infof("Starting REST proxy listener")
 	restListener, err := net.Listen("tcp", config.RESTListen)
 	if err != nil {
 		return fmt.Errorf("REST proxy unable to listen on %s",
@@ -115,14 +115,14 @@ func daemon(config *config) error {
 	go func() {
 		defer wg.Done()
 
-		logger.Infof("Starting swap client")
+		log.Infof("Starting swap client")
 		err := swapClient.Run(mainCtx, statusChan)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
-		logger.Infof("Swap client stopped")
+		log.Infof("Swap client stopped")
 
-		logger.Infof("Stopping gRPC server")
+		log.Infof("Stopping gRPC server")
 		grpcServer.Stop()
 
 		cancel()
@@ -133,7 +133,7 @@ func daemon(config *config) error {
 	go func() {
 		defer wg.Done()
 
-		logger.Infof("Waiting for updates")
+		log.Infof("Waiting for updates")
 		for {
 			select {
 			case swap := <-statusChan:
@@ -160,12 +160,12 @@ func daemon(config *config) error {
 	go func() {
 		defer wg.Done()
 
-		logger.Infof("RPC server listening on %s", grpcListener.Addr())
-		logger.Infof("REST proxy listening on %s", restListener.Addr())
+		log.Infof("RPC server listening on %s", grpcListener.Addr())
+		log.Infof("REST proxy listening on %s", restListener.Addr())
 
 		err = grpcServer.Serve(grpcListener)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 	}()
 
@@ -175,7 +175,7 @@ func daemon(config *config) error {
 	// Run until the users terminates loopd or an error occurred.
 	select {
 	case <-interruptChannel:
-		logger.Infof("Received SIGINT (Ctrl+C).")
+		log.Infof("Received SIGINT (Ctrl+C).")
 
 		// TODO: Remove debug code.
 		// Debug code to dump goroutines on hanging exit.

cmd/loopd/log.go

@@ -1,24 +1,40 @@
 package main
 
 import (
-	"os"
-
 	"github.com/btcsuite/btclog"
+	"github.com/lightninglabs/loop"
+	"github.com/lightninglabs/loop/lndclient"
+	"github.com/lightninglabs/loop/loopdb"
+	"github.com/lightningnetwork/lnd/build"
 )
 
-// log is a logger that is initialized with no output filters.  This means the
-// package will not perform any logging by default until the caller requests
-// it.
 var (
-	backendLog = btclog.NewBackend(logWriter{})
-	logger     = backendLog.Logger("LOOPD")
+	logWriter = build.NewRotatingLogWriter()
+
+	log = build.NewSubLogger("LOOPD", logWriter.GenSubLogger)
 )
 
-// logWriter implements an io.Writer that outputs to both standard output and
-// the write-end pipe of an initialized log rotator.
-type logWriter struct{}
-
-func (logWriter) Write(p []byte) (n int, err error) {
-	os.Stdout.Write(p)
-	return len(p), nil
+func init() {
+	setSubLogger("LOOPD", log, nil)
+	addSubLogger("LOOP", loop.UseLogger)
+	addSubLogger("LNDC", lndclient.UseLogger)
+	addSubLogger("STORE", loopdb.UseLogger)
+}
+
+// addSubLogger is a helper method to conveniently create and register the
+// logger of a sub system.
+func addSubLogger(subsystem string, useLogger func(btclog.Logger)) {
+	logger := build.NewSubLogger(subsystem, logWriter.GenSubLogger)
+	setSubLogger(subsystem, logger, useLogger)
+}
+
+// setSubLogger is a helper method to conveniently register the logger of a sub
+// system.
+func setSubLogger(subsystem string, logger btclog.Logger,
+	useLogger func(btclog.Logger)) {
+
+	logWriter.RegisterSubLogger(subsystem, logger)
+	if useLogger != nil {
+		useLogger(logger)
+	}
 }

cmd/loopd/main.go

@@ -7,10 +7,9 @@ import (
 	"strings"
 	"sync"
 
-	flags "github.com/jessevdk/go-flags"
-
-	"github.com/btcsuite/btcutil"
+	"github.com/jessevdk/go-flags"
 	"github.com/lightninglabs/loop"
+	"github.com/lightningnetwork/lnd/build"
 	"github.com/lightningnetwork/lnd/lntypes"
 )
 
@@ -19,7 +18,6 @@ const (
 )
 
 var (
-	loopDirBase           = btcutil.AppDataDir("loop", false)
 	defaultConfigFilename = "loopd.conf"
 
 	swaps            = make(map[lntypes.Hash]loop.SwapInfo)
@@ -81,8 +79,32 @@ func start() error {
 		os.Exit(0)
 	}
 
+	// Special show command to list supported subsystems and exit.
+	if config.DebugLevel == "show" {
+		fmt.Printf("Supported subsystems: %v\n",
+			logWriter.SupportedSubsystems())
+		os.Exit(0)
+	}
+
+	// Append the network type to the log directory so it is
+	// "namespaced" per network in the same fashion as the data directory.
+	config.LogDir = filepath.Join(config.LogDir, config.Network)
+
+	// Initialize logging at the default logging level.
+	err = logWriter.InitLogRotator(
+		filepath.Join(config.LogDir, defaultLogFilename),
+		config.MaxLogFileSize, config.MaxLogFiles,
+	)
+	if err != nil {
+		return err
+	}
+	err = build.ParseAndSetDebugLevels(config.DebugLevel, logWriter)
+	if err != nil {
+		return err
+	}
+
 	// Print the version before executing either primary directive.
-	logger.Infof("Version: %v", loop.Version())
+	log.Infof("Version: %v", loop.Version())
 
 	// Execute command.
 	if parser.Active == nil {

cmd/loopd/swapclient_server.go

@@ -40,7 +40,7 @@ func (s *swapClientServer) LoopOut(ctx context.Context,
 	in *looprpc.LoopOutRequest) (
 	*looprpc.SwapResponse, error) {
 
-	logger.Infof("Loop out request received")
+	log.Infof("Loop out request received")
 
 	sweepConfTarget, err := validateConfTarget(
 		in.SweepConfTarget, loop.DefaultSweepConfTarget,
@@ -82,7 +82,7 @@ func (s *swapClientServer) LoopOut(ctx context.Context,
 	}
 	hash, htlc, err := s.impl.LoopOut(ctx, req)
 	if err != nil {
-		logger.Errorf("LoopOut: %v", err)
+		log.Errorf("LoopOut: %v", err)
 		return nil, err
 	}
 
@@ -140,7 +140,7 @@ func (s *swapClientServer) marshallSwap(loopSwap *loop.SwapInfo) (
 func (s *swapClientServer) Monitor(in *looprpc.MonitorRequest,
 	server looprpc.SwapClient_MonitorServer) error {
 
-	logger.Infof("Monitor request received")
+	log.Infof("Monitor request received")
 
 	send := func(info loop.SwapInfo) error {
 		rpcSwap, err := s.marshallSwap(&info)
@@ -234,11 +234,11 @@ func (s *swapClientServer) Monitor(in *looprpc.MonitorRequest,
 func (s *swapClientServer) LoopOutTerms(ctx context.Context,
 	req *looprpc.TermsRequest) (*looprpc.TermsResponse, error) {
 
-	logger.Infof("Loop out terms request received")
+	log.Infof("Loop out terms request received")
 
 	terms, err := s.impl.LoopOutTerms(ctx)
 	if err != nil {
-		logger.Errorf("Terms request: %v", err)
+		log.Errorf("Terms request: %v", err)
 		return nil, err
 	}
 
@@ -280,11 +280,11 @@ func (s *swapClientServer) LoopOutQuote(ctx context.Context,
 func (s *swapClientServer) GetLoopInTerms(ctx context.Context, req *looprpc.TermsRequest) (
 	*looprpc.TermsResponse, error) {
 
-	logger.Infof("Loop in terms request received")
+	log.Infof("Loop in terms request received")
 
 	terms, err := s.impl.LoopInTerms(ctx)
 	if err != nil {
-		logger.Errorf("Terms request: %v", err)
+		log.Errorf("Terms request: %v", err)
 		return nil, err
 	}
 
@@ -298,7 +298,7 @@ func (s *swapClientServer) GetLoopInTerms(ctx context.Context, req *looprpc.Term
 func (s *swapClientServer) GetLoopInQuote(ctx context.Context,
 	req *looprpc.QuoteRequest) (*looprpc.QuoteResponse, error) {
 
-	logger.Infof("Loop in quote request received")
+	log.Infof("Loop in quote request received")
 
 	quote, err := s.impl.LoopInQuote(ctx, &loop.LoopInQuoteRequest{
 		Amount:         btcutil.Amount(req.Amt),
@@ -318,7 +318,7 @@ func (s *swapClientServer) LoopIn(ctx context.Context,
 	in *looprpc.LoopInRequest) (
 	*looprpc.SwapResponse, error) {
 
-	logger.Infof("Loop in request received")
+	log.Infof("Loop in request received")
 
 	req := &loop.LoopInRequest{
 		Amount:         btcutil.Amount(in.Amt),
@@ -332,7 +332,7 @@ func (s *swapClientServer) LoopIn(ctx context.Context,
 	}
 	hash, htlc, err := s.impl.LoopIn(ctx, req)
 	if err != nil {
-		logger.Errorf("Loop in: %v", err)
+		log.Errorf("Loop in: %v", err)
 		return nil, err
 	}
 

executor.go

@@ -59,7 +59,7 @@ func (s *executor) run(mainCtx context.Context,
 	// Before starting, make sure we have an up to date block height.
 	// Otherwise we might reveal a preimage for a swap that is already
 	// expired.
-	logger.Infof("Wait for first block ntfn")
+	log.Infof("Wait for first block ntfn")
 
 	var height int32
 	setHeight := func(h int32) {
@@ -77,7 +77,7 @@ func (s *executor) run(mainCtx context.Context,
 	}
 
 	// Start main event loop.
-	logger.Infof("Starting event loop at height %v", height)
+	log.Infof("Starting event loop at height %v", height)
 
 	// Signal that executor being ready with an up to date block height.
 	close(s.ready)

lndclient/lightning_client.go

@@ -253,7 +253,7 @@ func (s *lightningClient) payInvoice(ctx context.Context, invoice string,
 
 			// Paid successfully.
 			case PaymentResultSuccess:
-				logger.Infof(
+				log.Infof(
 					"Payment %v completed", hash,
 				)
 
@@ -274,7 +274,7 @@ func (s *lightningClient) payInvoice(ctx context.Context, invoice string,
 
 			// Invoice was already paid on a previous run.
 			case PaymentResultAlreadyPaid:
-				logger.Infof(
+				log.Infof(
 					"Payment %v already completed", hash,
 				)
 
@@ -294,7 +294,7 @@ func (s *lightningClient) payInvoice(ctx context.Context, invoice string,
 			// TODO: Improve this when lnd expose more API to
 			// tracking existing payments.
 			case PaymentResultInFlight:
-				logger.Infof(
+				log.Infof(
 					"Payment %v already in flight", hash,
 				)
 
@@ -302,7 +302,7 @@ func (s *lightningClient) payInvoice(ctx context.Context, invoice string,
 
 			// Other errors are transformed into an error struct.
 			default:
-				logger.Warnf(
+				log.Warnf(
 					"Payment %v failed: %v", hash,
 					payResp.PaymentError,
 				)

lndclient/lnd_services.go

@@ -84,13 +84,13 @@ func NewLndServices(lndAddress, application, network, macaroonDir,
 	}
 
 	// Setup connection with lnd
-	logger.Infof("Creating lnd connection to %v", lndAddress)
+	log.Infof("Creating lnd connection to %v", lndAddress)
 	conn, err := getClientConn(lndAddress, network, tlsPath)
 	if err != nil {
 		return nil, err
 	}
 
-	logger.Infof("Connected to lnd")
+	log.Infof("Connected to lnd")
 
 	chainParams, err := swap.ChainParamsFromNetwork(network)
 	if err != nil {
@@ -125,19 +125,19 @@ func NewLndServices(lndAddress, application, network, macaroonDir,
 	routerClient := newRouterClient(conn, macaroons.routerMac)
 
 	cleanup := func() {
-		logger.Debugf("Closing lnd connection")
+		log.Debugf("Closing lnd connection")
 		conn.Close()
 
-		logger.Debugf("Wait for client to finish")
+		log.Debugf("Wait for client to finish")
 		lightningClient.WaitForFinished()
 
-		logger.Debugf("Wait for chain notifier to finish")
+		log.Debugf("Wait for chain notifier to finish")
 		notifierClient.WaitForFinished()
 
-		logger.Debugf("Wait for invoices to finish")
+		log.Debugf("Wait for invoices to finish")
 		invoicesClient.WaitForFinished()
 
-		logger.Debugf("Lnd services finished")
+		log.Debugf("Lnd services finished")
 	}
 
 	services := &GrpcLndServices{
@@ -154,7 +154,7 @@ func NewLndServices(lndAddress, application, network, macaroonDir,
 		cleanup: cleanup,
 	}
 
-	logger.Infof("Using network %v", network)
+	log.Infof("Using network %v", network)
 
 	return services, nil
 }
@@ -164,7 +164,7 @@ func NewLndServices(lndAddress, application, network, macaroonDir,
 func (s *GrpcLndServices) Close() {
 	s.cleanup()
 
-	logger.Debugf("Lnd services finished")
+	log.Debugf("Lnd services finished")
 }
 
 var (

lndclient/log.go

@@ -1,24 +1,23 @@
 package lndclient
 
 import (
-	"os"
-
 	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/build"
 )
 
-// log is a logger that is initialized with no output filters.  This
-// means the package will not perform any logging by default until the caller
-// requests it.
-var (
-	backendLog = btclog.NewBackend(logWriter{})
-	logger     = backendLog.Logger("LNDCLIENT")
-)
+// log is a logger that is initialized with no output filters. This
+// means the package will not perform any logging by default until the
+// caller requests it.
+var log btclog.Logger
 
-// logWriter implements an io.Writer that outputs to both standard output and
-// the write-end pipe of an initialized log rotator.
-type logWriter struct{}
-
-func (logWriter) Write(p []byte) (n int, err error) {
-	os.Stdout.Write(p)
-	return len(p), nil
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger("LNDC", nil))
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
 }

log.go

@@ -1,24 +1,23 @@
 package loop
 
 import (
-	"os"
-
 	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/build"
 )
 
-// log is a logger that is initialized with no output filters.  This
-// means the package will not perform any logging by default until the caller
-// requests it.
-var (
-	backendLog = btclog.NewBackend(logWriter{})
-	logger     = backendLog.Logger("CLIENT")
-)
+// log is a logger that is initialized with no output filters. This
+// means the package will not perform any logging by default until the
+// caller requests it.
+var log btclog.Logger
 
-// logWriter implements an io.Writer that outputs to both standard output and
-// the write-end pipe of an initialized log rotator.
-type logWriter struct{}
-
-func (logWriter) Write(p []byte) (n int, err error) {
-	os.Stdout.Write(p)
-	return len(p), nil
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger("LOOP", nil))
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
 }

loopdb/log.go

@@ -1,21 +1,23 @@
 package loopdb
 
 import (
-	"os"
-
 	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/build"
 )
 
-var (
-	backendLog = btclog.NewBackend(logWriter{})
-	log        = backendLog.Logger("STORE")
-)
+// log is a logger that is initialized with no output filters. This
+// means the package will not perform any logging by default until the
+// caller requests it.
+var log btclog.Logger
 
-// logWriter implements an io.Writer that outputs to both standard output and
-// the write-end pipe of an initialized log rotator.
-type logWriter struct{}
-
-func (logWriter) Write(p []byte) (n int, err error) {
-	os.Stdout.Write(p)
-	return len(p), nil
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger("STORE", nil))
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
 }

loopin.go

@@ -67,7 +67,7 @@ func newLoopInSwap(globalCtx context.Context, cfg *swapConfig,
 	swapFee := quote.SwapFee
 
 	if swapFee > request.MaxSwapFee {
-		logger.Warnf("Swap fee %v exceeding maximum of %v",
+		log.Warnf("Swap fee %v exceeding maximum of %v",
 			swapFee, request.MaxSwapFee)
 
 		return nil, ErrSwapFeeTooHigh
@@ -81,7 +81,7 @@ func newLoopInSwap(globalCtx context.Context, cfg *swapConfig,
 	// Generate random preimage.
 	var swapPreimage lntypes.Preimage
 	if _, err := rand.Read(swapPreimage[:]); err != nil {
-		logger.Error("Cannot generate preimage")
+		log.Error("Cannot generate preimage")
 	}
 	swapHash := lntypes.Hash(sha256.Sum256(swapPreimage[:]))
 
@@ -111,7 +111,7 @@ func newLoopInSwap(globalCtx context.Context, cfg *swapConfig,
 	// Post the swap parameters to the swap server. The response contains
 	// the server success key and the expiry height of the on-chain swap
 	// htlc.
-	logger.Infof("Initiating swap request at height %v", currentHeight)
+	log.Infof("Initiating swap request at height %v", currentHeight)
 	swapResp, err := cfg.server.NewLoopInSwap(globalCtx, swapHash,
 		request.Amount, senderKey, swapInvoice,
 	)
@@ -179,7 +179,7 @@ func resumeLoopInSwap(reqContext context.Context, cfg *swapConfig,
 
 	hash := lntypes.Hash(sha256.Sum256(pend.Contract.Preimage[:]))
 
-	logger.Infof("Resuming loop in swap %v", hash)
+	log.Infof("Resuming loop in swap %v", hash)
 
 	swapKit, err := newSwapKit(
 		hash, swap.TypeIn, cfg, &pend.Contract.SwapContract,

loopin_test.go

@@ -52,7 +52,7 @@ func TestLoopInSuccess(t *testing.T) {
 	go func() {
 		err := swap.execute(context.Background(), ctx.cfg, height)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 		errChan <- err
 	}()
@@ -142,7 +142,7 @@ func TestLoopInTimeout(t *testing.T) {
 	go func() {
 		err := swap.execute(context.Background(), ctx.cfg, height)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 		errChan <- err
 	}()
@@ -289,7 +289,7 @@ func testLoopInResume(t *testing.T, state loopdb.SwapState, expired bool) {
 	go func() {
 		err := swap.execute(context.Background(), ctx.cfg, height)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 		errChan <- err
 	}()

loopout.go

@@ -61,7 +61,7 @@ func newLoopOutSwap(globalCtx context.Context, cfg *swapConfig,
 	// Generate random preimage.
 	var swapPreimage [32]byte
 	if _, err := rand.Read(swapPreimage[:]); err != nil {
-		logger.Error("Cannot generate preimage")
+		log.Error("Cannot generate preimage")
 	}
 	swapHash := lntypes.Hash(sha256.Sum256(swapPreimage[:]))
 
@@ -77,7 +77,7 @@ func newLoopOutSwap(globalCtx context.Context, cfg *swapConfig,
 
 	// Post the swap parameters to the swap server. The response contains
 	// the server revocation key and the swap and prepay invoices.
-	logger.Infof("Initiating swap request at height %v", currentHeight)
+	log.Infof("Initiating swap request at height %v", currentHeight)
 
 	swapResp, err := cfg.server.NewLoopOutSwap(globalCtx, swapHash,
 		request.Amount, receiverKey,
@@ -147,7 +147,7 @@ func resumeLoopOutSwap(reqContext context.Context, cfg *swapConfig,
 
 	hash := lntypes.Hash(sha256.Sum256(pend.Contract.Preimage[:]))
 
-	logger.Infof("Resuming loop out swap %v", hash)
+	log.Infof("Resuming loop out swap %v", hash)
 
 	swapKit, err := newSwapKit(
 		hash, swap.TypeOut, cfg, &pend.Contract.SwapContract,
@@ -309,7 +309,7 @@ func (s *loopOutSwap) executeSwap(globalCtx context.Context) error {
 
 	// Verify amount if preimage hasn't been revealed yet.
 	if s.state != loopdb.StatePreimageRevealed && htlcValue < s.AmountRequested {
-		logger.Warnf("Swap amount too low, expected %v but received %v",
+		log.Warnf("Swap amount too low, expected %v but received %v",
 			s.AmountRequested, htlcValue)
 
 		s.state = loopdb.StateFailInsufficientValue
@@ -494,7 +494,7 @@ func (s *loopOutSwap) waitForConfirmedHtlc(globalCtx context.Context) (
 			case notification := <-s.blockEpochChan:
 				s.height = notification.(int32)
 
-				logger.Infof("Received block %v", s.height)
+				log.Infof("Received block %v", s.height)
 
 				if checkMaxRevealHeightExceeded() {
 					return nil, nil
@@ -690,21 +690,21 @@ func validateLoopOutContract(lnd *lndclient.LndServices,
 
 	swapFee := swapInvoiceAmt + prepayInvoiceAmt - request.Amount
 	if swapFee > request.MaxSwapFee {
-		logger.Warnf("Swap fee %v exceeding maximum of %v",
+		log.Warnf("Swap fee %v exceeding maximum of %v",
 			swapFee, request.MaxSwapFee)
 
 		return ErrSwapFeeTooHigh
 	}
 
 	if prepayInvoiceAmt > request.MaxPrepayAmount {
-		logger.Warnf("Prepay amount %v exceeding maximum of %v",
+		log.Warnf("Prepay amount %v exceeding maximum of %v",
 			prepayInvoiceAmt, request.MaxPrepayAmount)
 
 		return ErrPrepayAmountTooHigh
 	}
 
 	if response.expiry-height < MinLoopOutPreimageRevealDelta {
-		logger.Warnf("Proposed expiry %v (delta %v) too soon",
+		log.Warnf("Proposed expiry %v (delta %v) too soon",
 			response.expiry, response.expiry-height)
 
 		return ErrExpiryTooSoon

loopout_test.go

@@ -62,7 +62,7 @@ func TestLateHtlcPublish(t *testing.T) {
 			timerFactory:   timerFactory,
 		}, height)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 		errChan <- err
 	}()
@@ -153,7 +153,7 @@ func TestCustomSweepConfTarget(t *testing.T) {
 			sweeper:        sweeper,
 		}, ctx.Lnd.Height)
 		if err != nil {
-			logger.Error(err)
+			log.Error(err)
 		}
 		errChan <- err
 	}()

swap.go

@@ -44,7 +44,7 @@ func newSwapKit(hash lntypes.Hash, swapType swap.Type, cfg *swapConfig,
 
 	log := &swap.PrefixLog{
 		Hash:   hash,
-		Logger: logger,
+		Logger: log,
 	}
 
 	// Log htlc address for debugging.

testcontext_test.go

@@ -114,7 +114,7 @@ func createClientTestContext(t *testing.T,
 			runCtx,
 			statusChan,
 		)
-		logger.Errorf("client run: %v", err)
+		log.Errorf("client run: %v", err)
 		ctx.runErr <- err
 	}()