loopd: persistent configuration

cmd/loopd/config.go

@@ -0,0 +1,30 @@
+package main
+
+type lndConfig struct {
+	Host         string `long:"host" description:"lnd instance rpc address"`
+	MacaroonPath string `long:"macaroonpath" description:"Path to lnd macaroon"`
+	TLSPath      string `long:"tlspath" description:"Path to lnd tls certificate"`
+}
+
+type viewParameters struct{}
+
+type config struct {
+	Insecure   bool   `long:"insecure" description:"disable tls"`
+	Network    string `long:"network" description:"network to run on" choice:"regtest" choice:"testnet" choice:"mainnet" choice:"simnet"`
+	SwapServer string `long:"swapserver" description:"swap server address host:port"`
+	Listen     string `long:"listen" description:"address to listen on for rpc lcients"`
+
+	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."`
+}
+
+var defaultConfig = config{
+	Network:    "mainnet",
+	SwapServer: "swap.lightning.today:11009",
+	Listen:     "localhost:11010",
+	Insecure:   false,
+	Lnd: &lndConfig{
+		Host: "localhost:10009",
+	},
+}

cmd/loopd/daemon.go

@@ -12,20 +12,21 @@ import (
 
 	"github.com/lightninglabs/loop"
 	"github.com/lightninglabs/loop/looprpc"
-	"github.com/urfave/cli"
 	"google.golang.org/grpc"
 )
 
-// daemon runs swapd in daemon mode. It will listen for grpc connections,
+// daemon runs loopd in daemon mode. It will listen for grpc connections,
 // execute commands and pass back swap status information.
-func daemon(ctx *cli.Context) error {
-	lnd, err := getLnd(ctx)
+func daemon(config *config) error {
+	lnd, err := getLnd(config.Network, config.Lnd)
 	if err != nil {
 		return err
 	}
 	defer lnd.Close()
 
-	swapClient, cleanup, err := getClient(ctx, &lnd.LndServices)
+	swapClient, cleanup, err := getClient(
+		config.Network, config.SwapServer, config.Insecure, &lnd.LndServices,
+	)
 	if err != nil {
 		return err
 	}
@@ -48,7 +49,7 @@ func daemon(ctx *cli.Context) error {
 		}
 	}
 
-	// Instantiate the swapd gRPC server.
+	// Instantiate the loopd gRPC server.
 	server := swapClientServer{
 		impl: swapClient,
 		lnd:  &lnd.LndServices,
@@ -60,10 +61,10 @@ func daemon(ctx *cli.Context) error {
 
 	// Next, Start the gRPC server listening for HTTP/2 connections.
 	logger.Infof("Starting RPC listener")
-	lis, err := net.Listen("tcp", defaultListenAddr)
+	lis, err := net.Listen("tcp", config.Listen)
 	if err != nil {
 		return fmt.Errorf("RPC server unable to listen on %s",
-			defaultListenAddr)
+			config.Listen)
 
 	}
 	defer lis.Close()
@@ -134,7 +135,7 @@ func daemon(ctx *cli.Context) error {
 	interruptChannel := make(chan os.Signal, 1)
 	signal.Notify(interruptChannel, os.Interrupt)
 
-	// Run until the users terminates swapd or an error occurred.
+	// Run until the users terminates loopd or an error occurred.
 	select {
 	case <-interruptChannel:
 		logger.Infof("Received SIGINT (Ctrl+C).")

cmd/loopd/log.go

@@ -11,7 +11,7 @@ import (
 // it.
 var (
 	backendLog = btclog.NewBackend(logWriter{})
-	logger     = backendLog.Logger("SWAPD")
+	logger     = backendLog.Logger("LOOPD")
 )
 
 // logWriter implements an io.Writer that outputs to both standard output and

cmd/loopd/main.go

@@ -3,22 +3,23 @@ package main
 import (
 	"fmt"
 	"os"
+	"path/filepath"
 	"sync"
 
+	flags "github.com/jessevdk/go-flags"
+
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/loop"
 	"github.com/lightningnetwork/lnd/lntypes"
-	"github.com/urfave/cli"
 )
 
 const (
-	defaultListenPort = 11010
 	defaultConfTarget = int32(2)
 )
 
 var (
-	defaultListenAddr = fmt.Sprintf("localhost:%d", defaultListenPort)
-	defaultSwapletDir = btcutil.AppDataDir("swaplet", false)
+	loopDirBase           = btcutil.AppDataDir("loop", false)
+	defaultConfigFilename = "loopd.conf"
 
 	swaps            = make(map[lntypes.Hash]loop.SwapInfo)
 	subscribers      = make(map[int]chan<- interface{})
@@ -27,47 +28,58 @@ var (
 )
 
 func main() {
-	app := cli.NewApp()
-
-	app.Flags = []cli.Flag{
-		cli.StringFlag{
-			Name:  "network",
-			Value: "mainnet",
-			Usage: "network to run on (regtest, testnet, mainnet)",
-		},
-		cli.StringFlag{
-			Name:  "lnd",
-			Value: "localhost:10009",
-			Usage: "lnd instance rpc address host:port",
-		},
-		cli.StringFlag{
-			Name:  "swapserver",
-			Value: "swap.lightning.today:11009",
-			Usage: "swap server address host:port",
-		},
-		cli.StringFlag{
-			Name:  "macaroonpath",
-			Usage: "path to lnd macaroon",
-		},
-		cli.StringFlag{
-			Name:  "tlspath",
-			Usage: "path to lnd tls certificate",
-		},
-		cli.BoolFlag{
-			Name:  "insecure",
-			Usage: "disable tls",
-		},
+	err := start()
+	if err != nil {
+		fmt.Println(err)
+	}
+}
+
+func start() error {
+	config := defaultConfig
+
+	// Parse command line flags.
+	parser := flags.NewParser(&config, flags.Default)
+	parser.SubcommandsOptional = true
+
+	_, err := parser.Parse()
+	if e, ok := err.(*flags.Error); ok && e.Type == flags.ErrHelp {
+		return nil
 	}
-	app.Name = "loopd"
-	app.Version = "0.0.1"
-	app.Usage = "Lightning Loop Client Daemon"
-	app.Commands = []cli.Command{
-		viewCommand,
+	if err != nil {
+		return err
 	}
-	app.Action = daemon
 
-	err := app.Run(os.Args)
+	// Parse ini file.
+	loopDir := filepath.Join(loopDirBase, config.Network)
+	if err := os.MkdirAll(loopDir, os.ModePerm); err != nil {
+		return err
+	}
+
+	configFile := filepath.Join(loopDir, defaultConfigFilename)
+	if err := flags.IniParse(configFile, &config); err != nil {
+		// If it's a parsing related error, then we'll return
+		// immediately, otherwise we can proceed as possibly the config
+		// file doesn't exist which is OK.
+		if _, ok := err.(*flags.IniError); ok {
+			return err
+		}
+	}
+
+	// Parse command line flags again to restore flags overwritten by ini
+	// parse.
+	_, err = parser.Parse()
 	if err != nil {
-		fmt.Println(err)
+		return err
 	}
+
+	// Execute command.
+	if parser.Active == nil {
+		return daemon(&config)
+	}
+
+	if parser.Active.Name == "view" {
+		return view(&config)
+	}
+
+	return fmt.Errorf("unimplemented command %v", parser.Active.Name)
 }

cmd/loopd/utils.go

@@ -6,33 +6,26 @@ import (
 
 	"github.com/lightninglabs/loop"
 	"github.com/lightninglabs/loop/lndclient"
-	"github.com/urfave/cli"
 )
 
 // getLnd returns an instance of the lnd services proxy.
-func getLnd(ctx *cli.Context) (*lndclient.GrpcLndServices, error) {
-	network := ctx.GlobalString("network")
-
-	return lndclient.NewLndServices(ctx.GlobalString("lnd"),
-		"client", network, ctx.GlobalString("macaroonpath"),
-		ctx.GlobalString("tlspath"),
+func getLnd(network string, cfg *lndConfig) (*lndclient.GrpcLndServices, error) {
+	return lndclient.NewLndServices(
+		cfg.Host, "client", network, cfg.MacaroonPath, cfg.TLSPath,
 	)
 }
 
 // getClient returns an instance of the swap client.
-func getClient(ctx *cli.Context,
+func getClient(network, swapServer string, insecure bool,
 	lnd *lndclient.LndServices) (*loop.Client, func(), error) {
 
-	network := ctx.GlobalString("network")
-
 	storeDir, err := getStoreDir(network)
 	if err != nil {
 		return nil, nil, err
 	}
 
 	swapClient, cleanUp, err := loop.NewClient(
-		storeDir, ctx.GlobalString("swapserver"),
-		ctx.GlobalBool("insecure"), lnd,
+		storeDir, swapServer, insecure, lnd,
 	)
 	if err != nil {
 		return nil, nil, err
@@ -42,7 +35,7 @@ func getClient(ctx *cli.Context,
 }
 
 func getStoreDir(network string) (string, error) {
-	dir := filepath.Join(defaultSwapletDir, network)
+	dir := filepath.Join(loopDirBase, network)
 	if err := os.MkdirAll(dir, os.ModePerm); err != nil {
 		return "", err
 	}

cmd/loopd/view.go

@@ -5,34 +5,24 @@ import (
 	"strconv"
 
 	"github.com/lightninglabs/loop/swap"
-	"github.com/urfave/cli"
 )
 
-var viewCommand = cli.Command{
-	Name: "view",
-	Usage: `view all swaps in the database. This command can only be 
-	executed when swapd is not running.`,
-	Description: `
-		Show all pending and completed swaps.`,
-	Action: view,
-}
-
 // view prints all swaps currently in the database.
-func view(ctx *cli.Context) error {
-	network := ctx.GlobalString("network")
-
-	chainParams, err := swap.ChainParamsFromNetwork(network)
+func view(config *config) error {
+	chainParams, err := swap.ChainParamsFromNetwork(config.Network)
 	if err != nil {
 		return err
 	}
 
-	lnd, err := getLnd(ctx)
+	lnd, err := getLnd(config.Network, config.Lnd)
 	if err != nil {
 		return err
 	}
 	defer lnd.Close()
 
-	swapClient, cleanup, err := getClient(ctx, &lnd.LndServices)
+	swapClient, cleanup, err := getClient(
+		config.Network, config.SwapServer, config.Insecure, &lnd.LndServices,
+	)
 	if err != nil {
 		return err
 	}
@@ -43,6 +33,10 @@ func view(ctx *cli.Context) error {
 		return err
 	}
 
+	if len(swaps) == 0 {
+		fmt.Printf("No swaps\n")
+	}
+
 	for _, s := range swaps {
 		htlc, err := swap.NewHtlc(
 			s.Contract.CltvExpiry,

lndclient/lnd_services.go

@@ -45,7 +45,7 @@ func NewLndServices(lndAddress string, application string,
 	*GrpcLndServices, error) {
 
 	// Setup connection with lnd
-	logger.Infof("Creating lnd connection")
+	logger.Infof("Creating lnd connection to %v", lndAddress)
 	conn, err := getClientConn(lndAddress, network, macPath, tlsPath)
 	if err != nil {
 		return nil, err