subservers: add new package to manage the lit subservers

Author: ellemouton

config.go

@@ -20,6 +20,7 @@ import (
 	"github.com/lightninglabs/lightning-terminal/autopilotserver"
 	"github.com/lightninglabs/lightning-terminal/firewall"
 	mid "github.com/lightninglabs/lightning-terminal/rpcmiddleware"
+	"github.com/lightninglabs/lightning-terminal/subservers"
 	"github.com/lightninglabs/lndclient"
 	"github.com/lightninglabs/loop/loopd"
 	"github.com/lightninglabs/pool"
@@ -169,7 +170,7 @@ type Config struct {
 	// That way only one global network flag is needed.
 	Network string `long:"network" description:"The network the UI and all its components run on" choice:"regtest" choice:"testnet" choice:"mainnet" choice:"simnet"`
 
-	Remote *RemoteConfig `group:"Remote mode options (use when lnd-mode=remote)" namespace:"remote"`
+	Remote *subservers.RemoteConfig `group:"Remote mode options (use when lnd-mode=remote)" namespace:"remote"`
 
 	// LndMode is the selected mode to run lnd in. The supported modes are
 	// 'integrated' and 'remote'. We only use a string instead of a bool
@@ -212,40 +213,6 @@ type Config struct {
 	lndAdminMacaroon []byte
 }
 
-// RemoteConfig holds the configuration parameters that are needed when running
-// LiT in the "remote" lnd mode.
-type RemoteConfig struct {
-	LitLogDir         string `long:"lit-logdir" description:"For lnd remote mode only: Directory to log output."`
-	LitMaxLogFiles    int    `long:"lit-maxlogfiles" description:"For lnd remote mode only: Maximum logfiles to keep (0 for no rotation)"`
-	LitMaxLogFileSize int    `long:"lit-maxlogfilesize" description:"For lnd remote mode only: Maximum logfile size in MB"`
-
-	LitDebugLevel string `long:"lit-debuglevel" description:"For lnd remote mode only: 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."`
-
-	Lnd     *RemoteDaemonConfig `group:"Remote lnd (use when lnd-mode=remote)" namespace:"lnd"`
-	Faraday *RemoteDaemonConfig `group:"Remote faraday (use when faraday-mode=remote)" namespace:"faraday"`
-	Loop    *RemoteDaemonConfig `group:"Remote loop (use when loop-mode=remote)" namespace:"loop"`
-	Pool    *RemoteDaemonConfig `group:"Remote pool (use when pool-mode=remote)" namespace:"pool"`
-}
-
-// RemoteDaemonConfig holds the configuration parameters that are needed to
-// connect to a remote daemon like lnd for example.
-type RemoteDaemonConfig struct {
-	// RPCServer is host:port that the remote daemon's RPC server is
-	// listening on.
-	RPCServer string `long:"rpcserver" description:"The host:port that the remote daemon is listening for RPC connections on."`
-
-	// MacaroonPath is the path to the single macaroon that should be used
-	// instead of needing to specify the macaroon directory that contains
-	// all of the daemon's macaroons. The specified macaroon MUST have all
-	// permissions that all the subservers use, otherwise permission errors
-	// will occur.
-	MacaroonPath string `long:"macaroonpath" description:"The full path to the single macaroon to use, either the main (admin.macaroon in lnd's case) or a custom baked one. A custom macaroon must contain ALL permissions required for all subservers to work, otherwise permission errors will occur."`
-
-	// TLSCertPath is the path to the tls cert of the remote daemon that
-	// should be used to verify the TLS identity of the remote RPC server.
-	TLSCertPath string `long:"tlscertpath" description:"The full path to the remote daemon's TLS cert to use for RPC connection verification."`
-}
-
 // lndConnectParams returns the connection parameters to connect to the local
 // lnd instance.
 func (c *Config) lndConnectParams() (string, lndclient.Network, string,
@@ -289,27 +256,27 @@ func defaultConfig() *Config {
 		HTTPSListen: defaultHTTPSListen,
 		TLSCertPath: DefaultTLSCertPath,
 		TLSKeyPath:  defaultTLSKeyPath,
-		Remote: &RemoteConfig{
+		Remote: &subservers.RemoteConfig{
 			LitDebugLevel:     defaultLogLevel,
 			LitLogDir:         defaultLogDir,
 			LitMaxLogFiles:    defaultMaxLogFiles,
 			LitMaxLogFileSize: defaultMaxLogFileSize,
-			Lnd: &RemoteDaemonConfig{
+			Lnd: &subservers.RemoteDaemonConfig{
 				RPCServer:    defaultRemoteLndRpcServer,
 				MacaroonPath: DefaultRemoteLndMacaroonPath,
 				TLSCertPath:  lndDefaultConfig.TLSCertPath,
 			},
-			Faraday: &RemoteDaemonConfig{
+			Faraday: &subservers.RemoteDaemonConfig{
 				RPCServer:    defaultRemoteFaradayRpcServer,
 				MacaroonPath: faradayDefaultConfig.MacaroonPath,
 				TLSCertPath:  faradayDefaultConfig.TLSCertPath,
 			},
-			Loop: &RemoteDaemonConfig{
+			Loop: &subservers.RemoteDaemonConfig{
 				RPCServer:    defaultRemoteLoopRpcServer,
 				MacaroonPath: loopDefaultConfig.MacaroonPath,
 				TLSCertPath:  loopDefaultConfig.TLSCertPath,
 			},
-			Pool: &RemoteDaemonConfig{
+			Pool: &subservers.RemoteDaemonConfig{
 				RPCServer:    defaultRemotePoolRpcServer,
 				MacaroonPath: poolDefaultConfig.MacaroonPath,
 				TLSCertPath:  poolDefaultConfig.TLSCertPath,

log.go

@@ -10,6 +10,7 @@ import (
 	mid "github.com/lightninglabs/lightning-terminal/rpcmiddleware"
 	"github.com/lightninglabs/lightning-terminal/rules"
 	"github.com/lightninglabs/lightning-terminal/session"
+	"github.com/lightninglabs/lightning-terminal/subservers"
 	"github.com/lightninglabs/loop/loopd"
 	"github.com/lightninglabs/pool"
 	"github.com/lightningnetwork/lnd"
@@ -77,6 +78,10 @@ func SetupLoggers(root *build.RotatingLogWriter, intercept signal.Interceptor) {
 		autopilotserver.UseLogger,
 	)
 
+	lnd.AddSubLogger(
+		root, subservers.Subsystem, intercept, subservers.UseLogger,
+	)
+
 	// Add daemon loggers to lnd's root logger.
 	faraday.SetupLoggers(root, intercept)
 	loopd.SetupLoggers(root, intercept)

subservers/config.go

@@ -0,0 +1,35 @@
+package subservers
+
+// RemoteConfig holds the configuration parameters that are needed when running
+// LiT in the "remote" lnd mode.
+type RemoteConfig struct {
+	LitLogDir         string `long:"lit-logdir" description:"For lnd remote mode only: Directory to log output."`
+	LitMaxLogFiles    int    `long:"lit-maxlogfiles" description:"For lnd remote mode only: Maximum logfiles to keep (0 for no rotation)"`
+	LitMaxLogFileSize int    `long:"lit-maxlogfilesize" description:"For lnd remote mode only: Maximum logfile size in MB"`
+
+	LitDebugLevel string `long:"lit-debuglevel" description:"For lnd remote mode only: 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."`
+
+	Lnd     *RemoteDaemonConfig `group:"Remote lnd (use when lnd-mode=remote)" namespace:"lnd"`
+	Faraday *RemoteDaemonConfig `group:"Remote faraday (use when faraday-mode=remote)" namespace:"faraday"`
+	Loop    *RemoteDaemonConfig `group:"Remote loop (use when loop-mode=remote)" namespace:"loop"`
+	Pool    *RemoteDaemonConfig `group:"Remote pool (use when pool-mode=remote)" namespace:"pool"`
+}
+
+// RemoteDaemonConfig holds the configuration parameters that are needed to
+// connect to a remote daemon like lnd for example.
+type RemoteDaemonConfig struct {
+	// RPCServer is host:port that the remote daemon's RPC server is
+	// listening on.
+	RPCServer string `long:"rpcserver" description:"The host:port that the remote daemon is listening for RPC connections on."`
+
+	// MacaroonPath is the path to the single macaroon that should be used
+	// instead of needing to specify the macaroon directory that contains
+	// all of the daemon's macaroons. The specified macaroon MUST have all
+	// permissions that all the subservers use, otherwise permission errors
+	// will occur.
+	MacaroonPath string `long:"macaroonpath" description:"The full path to the single macaroon to use, either the main (admin.macaroon in lnd's case) or a custom baked one. A custom macaroon must contain ALL permissions required for all subservers to work, otherwise permission errors will occur."`
+
+	// TLSCertPath is the path to the tls cert of the remote daemon that
+	// should be used to verify the TLS identity of the remote RPC server.
+	TLSCertPath string `long:"tlscertpath" description:"The full path to the remote daemon's TLS cert to use for RPC connection verification."`
+}

subservers/interface.go

@@ -0,0 +1,48 @@
+package subservers
+
+import (
+	"github.com/lightninglabs/lndclient"
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/macaroons"
+	"google.golang.org/grpc"
+)
+
+// SubServer defines an interface that should be implemented by any sub-server
+// that the subServer manager should manage. A sub-server can be run in either
+// integrated or remote mode. A sub-server is considered non-fatal to LiT
+// meaning that if a sub-server fails to start, LiT can safely continue with its
+// operations and other sub-servers can too.
+type SubServer interface {
+	macaroons.MacaroonValidator
+
+	// Name returns the name of the sub-server.
+	Name() string
+
+	// Remote returns true if the sub-server is running remotely and so
+	// should be connected to instead of spinning up an integrated server.
+	Remote() bool
+
+	// RemoteConfig returns the config required to connect to the sub-server
+	// if it is running in remote mode.
+	RemoteConfig() *RemoteDaemonConfig
+
+	// Start starts the sub-server in integrated mode.
+	Start(lnrpc.LightningClient, *lndclient.GrpcLndServices, bool) error
+
+	// Stop stops the sub-server in integrated mode.
+	Stop() error
+
+	// RegisterGrpcService must register the sub-server's GRPC server with
+	// the given registrar.
+	RegisterGrpcService(grpc.ServiceRegistrar)
+
+	// ServerErrChan returns an error channel that should be listened on
+	// after starting the sub-server to listen for any runtime errors. It
+	// is optional and may be set to nil. This only applies in integrated
+	// mode.
+	ServerErrChan() chan error
+
+	// MacPath returns the path to the sub-server's macaroon if it is not
+	// running in remote mode.
+	MacPath() string
+}

subservers/log.go

@@ -0,0 +1,25 @@
+package subservers
+
+import (
+	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/build"
+)
+
+const Subsystem = "SSVR"
+
+// 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
+
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger(Subsystem, 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
+}