lnd: properly switch RPC port with target net change

With this commit, support for changing the target network (testnet,
simnet, etc) has been finalized. Previously a command line option was
present to swap networks, but the RPC port wouldn’t automatically be
updated to reflect the network.

config.go

@@ -9,7 +9,6 @@ import (
 	"strings"
 
 	flags "github.com/btcsuite/go-flags"
-	"github.com/roasbeef/btcd/chaincfg"
 	"github.com/roasbeef/btcutil"
 )
 
@@ -34,10 +33,6 @@ var (
 	defaultDataDir    = filepath.Join(lndHomeDir, defaultDataDirname)
 	defaultLogDir     = filepath.Join(lndHomeDir, defaultLogDirname)
 
-	// activeNetParams is a pointer to the parameters specific to the
-	// currently active bitcoin network.
-	activeNetParams = &chaincfg.SegNet4Params
-
 	btcdHomeDir        = btcutil.AppDataDir("btcd", false)
 	defaultRPCKeyFile  = filepath.Join(btcdHomeDir, "rpc.key")
 	defaultRPCCertFile = filepath.Join(btcdHomeDir, "rpc.cert")
@@ -154,15 +149,11 @@ func loadConfig() (*config, error) {
 	numNets := 0
 	if cfg.TestNet3 {
 		numNets++
-		activeNetParams = &chaincfg.TestNet3Params
-	}
-	if cfg.SegNet {
-		numNets++
-		activeNetParams = &chaincfg.SegNet4Params
+		activeNetParams = testNetParams
 	}
 	if cfg.SimNet {
 		numNets++
-		activeNetParams = &chaincfg.SimNetParams
+		activeNetParams = simNetParams
 	}
 	if numNets > 1 {
 		str := "%s: The testnet, segnet, and simnet params can't be " +

fundingmanager.go

@@ -331,7 +331,7 @@ func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
 
 	// With our portion of the reservation initialied, process the
 	// initiators contribution to the channel.
-	_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript, activeNetParams)
+	_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript, activeNetParams.Params)
 	if err != nil {
 		fndgLog.Errorf("Unable to extract addresses from script: %v", err)
 		return
@@ -390,7 +390,7 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 	// contribution. At this point, we can process their contribution which
 	// allows us to construct and sign both the commitment transaction, and
 	// the funding transaction.
-	_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript, activeNetParams)
+	_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript, activeNetParams.Params)
 	if err != nil {
 		fndgLog.Errorf("Unable to extract addresses from script: %v", err)
 		return

lnd.go

@@ -40,7 +40,7 @@ func lndMain() error {
 	ltndLog.Infof("Version %s", version())
 
 	if loadedConfig.SPVMode == true {
-		shell(loadedConfig.SPVHostAdr, activeNetParams)
+		shell(loadedConfig.SPVHostAdr, activeNetParams.Params)
 		return err
 	}
 
@@ -57,7 +57,7 @@ func lndMain() error {
 
 	// Open the channeldb, which is dedicated to storing channel, and
 	// network related meta-data.
-	chanDB, err := channeldb.Open(loadedConfig.DataDir, activeNetParams)
+	chanDB, err := channeldb.Open(loadedConfig.DataDir, activeNetParams.Params)
 	if err != nil {
 		fmt.Println("unable to open channeldb: ", err)
 		return err
@@ -82,11 +82,11 @@ func lndMain() error {
 	config := &lnwallet.Config{
 		PrivatePass: []byte("hello"),
 		DataDir:     filepath.Join(loadedConfig.DataDir, "lnwallet"),
-		RpcHost:     loadedConfig.RPCHost,
+		RpcHost:     fmt.Sprintf("%v:%v", loadedConfig.RPCHost, activeNetParams.rpcPort),
 		RpcUser:     loadedConfig.RPCUser,
 		RpcPass:     loadedConfig.RPCPass,
 		CACert:      cert,
-		NetParams:   activeNetParams,
+		NetParams:   activeNetParams.Params,
 	}
 	wallet, err := lnwallet.NewLightningWallet(config, chanDB)
 	if err != nil {
@@ -151,6 +151,7 @@ func main() {
 	// Call the "real" main in a nested manner so the defers will properly
 	// be executed in the case of a graceful shutdown.
 	if err := lndMain(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
 }

params.go

@@ -0,0 +1,33 @@
+package main
+
+import "github.com/roasbeef/btcd/chaincfg"
+
+// activeNetParams is a pointer to the parameters specific to the currently
+// active bitcoin network.
+var activeNetParams = segNetParams
+
+// netParams couples the p2p parameters of a network with the corresponding RPC
+// port of a daemon running on the particular network.
+type netParams struct {
+	*chaincfg.Params
+	rpcPort string
+}
+
+// testNetParams contains parameters specific to the 3rd version of the test network.
+var testNetParams = netParams{
+	Params:  &chaincfg.TestNet3Params,
+	rpcPort: "18334",
+}
+
+// segNetParams contains parameters specific to the segregated witness test
+// network.
+var segNetParams = netParams{
+	Params:  &chaincfg.SegNet4Params,
+	rpcPort: "28902",
+}
+
+// simNetParams contains parameters specific to the simulation test network.
+var simNetParams = netParams{
+	Params:  &chaincfg.SimNetParams,
+	rpcPort: "18556",
+}

rpcserver.go

@@ -71,7 +71,7 @@ func (r *rpcServer) Stop() error {
 func addrPairsToOutputs(addrPairs map[string]int64) ([]*wire.TxOut, error) {
 	outputs := make([]*wire.TxOut, 0, len(addrPairs))
 	for addr, amt := range addrPairs {
-		addr, err := btcutil.DecodeAddress(addr, activeNetParams)
+		addr, err := btcutil.DecodeAddress(addr, activeNetParams.Params)
 		if err != nil {
 			return nil, err
 		}
@@ -286,7 +286,7 @@ func (r *rpcServer) GetInfo(ctx context.Context,
 	pendingChannels := r.server.fundingMgr.NumPendingChannels()
 
 	idPub := r.server.identityPriv.PubKey().SerializeCompressed()
-	idAddr, err := btcutil.NewAddressPubKeyHash(btcutil.Hash160(idPub), activeNetParams)
+	idAddr, err := btcutil.NewAddressPubKeyHash(btcutil.Hash160(idPub), activeNetParams.Params)
 	if err != nil {
 		return nil, err
 	}