invoicesrpc: create sub server

Sub server implementation is still empty. This is a preparatory
step for adding invoice functionality.

lnd.go

@@ -337,7 +337,7 @@ func lndMain() error {
 	// exported by the rpcServer.
 	rpcServer, err := newRPCServer(
 		server, macaroonService, cfg.SubRPCServers, serverOpts,
-		proxyOpts, atplManager, tlsConf,
+		proxyOpts, atplManager, server.invoices, tlsConf,
 	)
 	if err != nil {
 		srvrLog.Errorf("unable to start RPC server: %v", err)

lnrpc/invoicesrpc/config_active.go

@@ -0,0 +1,16 @@
+// +build invoicesrpc
+
+package invoicesrpc
+
+import (
+	"github.com/lightningnetwork/lnd/invoices"
+)
+
+// Config is the primary configuration struct for the invoices RPC server. It
+// contains all the items required for the rpc server to carry out its
+// duties. The fields with struct tags are meant to be parsed as normal
+// configuration options, while if able to be populated, the latter fields MUST
+// also be specified.
+type Config struct {
+	InvoiceRegistry *invoices.InvoiceRegistry
+}

lnrpc/invoicesrpc/config_default.go

@@ -0,0 +1,6 @@
+// +build !invoicesrpc
+
+package invoicesrpc
+
+// Config is empty for non-invoicesrpc builds.
+type Config struct{}

lnrpc/invoicesrpc/driver.go

@@ -0,0 +1,55 @@
+// +build invoicesrpc
+
+package invoicesrpc
+
+import (
+	"fmt"
+
+	"github.com/lightningnetwork/lnd/lnrpc"
+)
+
+// createNewSubServer is a helper method that will create the new sub server
+// given the main config dispatcher method. If we're unable to find the config
+// that is meant for us in the config dispatcher, then we'll exit with an
+// error.
+func createNewSubServer(configRegistry lnrpc.SubServerConfigDispatcher) (
+	lnrpc.SubServer, lnrpc.MacaroonPerms, error) {
+
+	// We'll attempt to look up the config that we expect, according to our
+	// subServerName name. If we can't find this, then we'll exit with an
+	// error, as we're unable to properly initialize ourselves without this
+	// config.
+	subServerConf, ok := configRegistry.FetchConfig(subServerName)
+	if !ok {
+		return nil, nil, fmt.Errorf("unable to find config for "+
+			"subserver type %s", subServerName)
+	}
+
+	// Now that we've found an object mapping to our service name, we'll
+	// ensure that it's the type we need.
+	config, ok := subServerConf.(*Config)
+	if !ok {
+		return nil, nil, fmt.Errorf("wrong type of config for "+
+			"subserver %s, expected %T got %T", subServerName,
+			&Config{}, subServerConf)
+	}
+
+	return New(config)
+}
+
+func init() {
+	subServer := &lnrpc.SubServerDriver{
+		SubServerName: subServerName,
+		New: func(c lnrpc.SubServerConfigDispatcher) (lnrpc.SubServer,
+			lnrpc.MacaroonPerms, error) {
+			return createNewSubServer(c)
+		},
+	}
+
+	// If the build tag is active, then we'll register ourselves as a
+	// sub-RPC server within the global lnrpc package namespace.
+	if err := lnrpc.RegisterSubServer(subServer); err != nil {
+		panic(fmt.Sprintf("failed to register sub server driver "+
+			"'%s': %v", subServerName, err))
+	}
+}

lnrpc/invoicesrpc/invoices.pb.go

@@ -0,0 +1,77 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: invoicesrpc/invoices.proto
+
+package invoicesrpc // import "github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+import (
+	context "golang.org/x/net/context"
+	grpc "google.golang.org/grpc"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ context.Context
+var _ grpc.ClientConn
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+const _ = grpc.SupportPackageIsVersion4
+
+// InvoicesClient is the client API for Invoices service.
+//
+// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
+type InvoicesClient interface {
+}
+
+type invoicesClient struct {
+	cc *grpc.ClientConn
+}
+
+func NewInvoicesClient(cc *grpc.ClientConn) InvoicesClient {
+	return &invoicesClient{cc}
+}
+
+// InvoicesServer is the server API for Invoices service.
+type InvoicesServer interface {
+}
+
+func RegisterInvoicesServer(s *grpc.Server, srv InvoicesServer) {
+	s.RegisterService(&_Invoices_serviceDesc, srv)
+}
+
+var _Invoices_serviceDesc = grpc.ServiceDesc{
+	ServiceName: "invoicesrpc.Invoices",
+	HandlerType: (*InvoicesServer)(nil),
+	Methods:     []grpc.MethodDesc{},
+	Streams:     []grpc.StreamDesc{},
+	Metadata:    "invoicesrpc/invoices.proto",
+}
+
+func init() {
+	proto.RegisterFile("invoicesrpc/invoices.proto", fileDescriptor_invoices_560fa62749d29606)
+}
+
+var fileDescriptor_invoices_560fa62749d29606 = []byte{
+	// 105 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0xca, 0xcc, 0x2b, 0xcb,
+	0xcf, 0x4c, 0x4e, 0x2d, 0x2e, 0x2a, 0x48, 0xd6, 0x87, 0xb1, 0xf5, 0x0a, 0x8a, 0xf2, 0x4b, 0xf2,
+	0x85, 0xb8, 0x91, 0xe4, 0x8c, 0xb8, 0xb8, 0x38, 0x3c, 0xa1, 0x5c, 0x27, 0xe3, 0x28, 0xc3, 0xf4,
+	0xcc, 0x92, 0x8c, 0xd2, 0x24, 0xbd, 0xe4, 0xfc, 0x5c, 0xfd, 0x9c, 0xcc, 0xf4, 0x8c, 0x92, 0xbc,
+	0xcc, 0xbc, 0xf4, 0xbc, 0xd4, 0x92, 0xf2, 0xfc, 0xa2, 0x6c, 0xfd, 0x9c, 0xbc, 0x14, 0xfd, 0x9c,
+	0x3c, 0x64, 0x03, 0x8b, 0x0a, 0x92, 0x93, 0xd8, 0xc0, 0x86, 0x1a, 0x03, 0x02, 0x00, 0x00, 0xff,
+	0xff, 0xaa, 0xe0, 0xa9, 0x52, 0x72, 0x00, 0x00, 0x00,
+}

lnrpc/invoicesrpc/invoices.proto

@@ -0,0 +1,11 @@
+syntax = "proto3";
+
+package invoicesrpc;
+
+option go_package = "github.com/lightningnetwork/lnd/lnrpc/invoicesrpc";
+
+// Invoices is a service that can be used to create, accept, settle and cancel
+// invoices.
+service Invoices {
+}
+

lnrpc/invoicesrpc/invoices_server.go

@@ -0,0 +1,89 @@
+// +build invoicesrpc
+
+package invoicesrpc
+
+import (
+	"github.com/lightningnetwork/lnd/lnrpc"
+	"google.golang.org/grpc"
+	"gopkg.in/macaroon-bakery.v2/bakery"
+)
+
+const (
+	// subServerName is the name of the sub rpc server. We'll use this name
+	// to register ourselves, and we also require that the main
+	// SubServerConfigDispatcher instance recognize it as the name of our
+	// RPC service.
+	subServerName = "InvoicesRPC"
+)
+
+var (
+	// macPermissions maps RPC calls to the permissions they require.
+	macPermissions = map[string][]bakery.Op{}
+)
+
+// Server is a sub-server of the main RPC server: the invoices RPC. This sub
+// RPC server allows external callers to access the status of the invoices
+// currently active within lnd, as well as configuring it at runtime.
+type Server struct {
+	started  int32 // To be used atomically.
+	shutdown int32 // To be used atomically.
+
+	cfg *Config
+}
+
+// A compile time check to ensure that Server fully implements the
+// InvoicesServer gRPC service.
+var _ InvoicesServer = (*Server)(nil)
+
+// New returns a new instance of the invoicesrpc Invoices sub-server. We also
+// return the set of permissions for the macaroons that we may create within
+// this method. If the macaroons we need aren't found in the filepath, then
+// we'll create them on start up. If we're unable to locate, or create the
+// macaroons we need, then we'll return with an error.
+func New(cfg *Config) (*Server, lnrpc.MacaroonPerms, error) {
+	// We don't create any new macaroons for this subserver, instead reuse
+	// existing onchain/offchain permissions.
+	server := &Server{
+		cfg: cfg,
+	}
+
+	return server, macPermissions, nil
+}
+
+// Start launches any helper goroutines required for the Server to function.
+//
+// NOTE: This is part of the lnrpc.SubServer interface.
+func (s *Server) Start() error {
+	return nil
+}
+
+// Stop signals any active goroutines for a graceful closure.
+//
+// NOTE: This is part of the lnrpc.SubServer interface.
+func (s *Server) Stop() error {
+	return nil
+}
+
+// Name returns a unique string representation of the sub-server. This can be
+// used to identify the sub-server and also de-duplicate them.
+//
+// NOTE: This is part of the lnrpc.SubServer interface.
+func (s *Server) Name() string {
+	return subServerName
+}
+
+// RegisterWithRootServer will be called by the root gRPC server to direct a sub
+// RPC server to register itself with the main gRPC root server. Until this is
+// called, each sub-server won't be able to have requests routed towards it.
+//
+// NOTE: This is part of the lnrpc.SubServer interface.
+func (s *Server) RegisterWithRootServer(grpcServer *grpc.Server) error {
+	// We make sure that we register it with the main gRPC server to ensure
+	// all our methods are routed properly.
+	RegisterInvoicesServer(grpcServer, s)
+
+	log.Debugf("Invoices RPC server successfully register with root " +
+		"gRPC server")
+
+	return nil
+}

lnrpc/invoicesrpc/log.go

@@ -0,0 +1,45 @@
+package invoicesrpc
+
+import (
+	"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 log btclog.Logger
+
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger("IRPC", nil))
+}
+
+// DisableLog disables all library log output.  Logging output is disabled by
+// by default until UseLogger is called.
+func DisableLog() {
+	UseLogger(btclog.Disabled)
+}
+
+// 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
+}
+
+// logClosure is used to provide a closure over expensive logging operations so
+// don't have to be performed when the logging level doesn't warrant it.
+type logClosure func() string
+
+// String invokes the underlying function and returns the result.
+func (c logClosure) String() string {
+	return c()
+}
+
+// newLogClosure returns a new closure over a function that returns a string
+// which itself provides a Stringer interface so that it can be used with the
+// logging system.
+func newLogClosure(c func() string) logClosure {
+	return logClosure(c)
+}

log.go

@@ -21,6 +21,7 @@ import (
 	"github.com/lightningnetwork/lnd/invoices"
 	"github.com/lightningnetwork/lnd/lnrpc/autopilotrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/chainrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 	"github.com/lightningnetwork/lnd/lnwallet"
@@ -78,6 +79,7 @@ var (
 	nannLog = build.NewSubLogger("NANN", backendLog.Logger)
 	wtwrLog = build.NewSubLogger("WTWR", backendLog.Logger)
 	ntfrLog = build.NewSubLogger("NTFR", backendLog.Logger)
+	irpcLog = build.NewSubLogger("IRPC", backendLog.Logger)
 )
 
 // Initialize package-global logger variables.
@@ -102,6 +104,7 @@ func init() {
 	netann.UseLogger(nannLog)
 	watchtower.UseLogger(wtwrLog)
 	chainrpc.UseLogger(ntfrLog)
+	invoicesrpc.UseLogger(irpcLog)
 }
 
 // subsystemLoggers maps each subsystem identifier to its associated logger.
@@ -132,6 +135,7 @@ var subsystemLoggers = map[string]btclog.Logger{
 	"NANN": nannLog,
 	"WTWR": wtwrLog,
 	"NTFR": ntfnLog,
+	"IRPC": irpcLog,
 }
 
 // initLogRotator initializes the logging rotator to write logs to logFile and

rpcserver.go

@@ -397,6 +397,7 @@ var _ lnrpc.LightningServer = (*rpcServer)(nil)
 func newRPCServer(s *server, macService *macaroons.Service,
 	subServerCgs *subRPCServerConfigs, serverOpts []grpc.ServerOption,
 	restServerOpts []grpc.DialOption, atpl *autopilot.Manager,
+	invoiceRegistry *invoices.InvoiceRegistry,
 	tlsCfg *tls.Config) (*rpcServer, error) {
 
 	var (
@@ -408,7 +409,7 @@ func newRPCServer(s *server, macService *macaroons.Service,
 	// the dependencies they need are properly populated within each sub
 	// server configuration struct.
 	err := subServerCgs.PopulateDependencies(
-		s.cc, networkDir, macService, atpl,
+		s.cc, networkDir, macService, atpl, invoiceRegistry,
 	)
 	if err != nil {
 		return nil, err

subrpcserver_config.go

@@ -5,8 +5,10 @@ import (
 	"reflect"
 
 	"github.com/lightningnetwork/lnd/autopilot"
+	"github.com/lightningnetwork/lnd/invoices"
 	"github.com/lightningnetwork/lnd/lnrpc/autopilotrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/chainrpc"
+	"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/signrpc"
 	"github.com/lightningnetwork/lnd/lnrpc/walletrpc"
 	"github.com/lightningnetwork/lnd/macaroons"
@@ -37,6 +39,10 @@ type subRPCServerConfigs struct {
 	// client to be notified of certain on-chain events (new blocks,
 	// confirmations, spends).
 	ChainRPC *chainrpc.Config `group:"chainrpc" namespace:"chainrpc"`
+
+	// InvoicesRPC is a sub-RPC server that exposes invoice related methods
+	// as a gRPC service.
+	InvoicesRPC *invoicesrpc.Config `group:"invoicesrpc" namespace:"invoicesrpc"`
 }
 
 // PopulateDependencies attempts to iterate through all the sub-server configs
@@ -47,7 +53,8 @@ type subRPCServerConfigs struct {
 // FetchConfig method.
 func (s *subRPCServerConfigs) PopulateDependencies(cc *chainControl,
 	networkDir string, macService *macaroons.Service,
-	atpl *autopilot.Manager) error {
+	atpl *autopilot.Manager,
+	invoiceRegistry *invoices.InvoiceRegistry) error {
 
 	// First, we'll use reflect to obtain a version of the config struct
 	// that allows us to programmatically inspect its fields.
@@ -125,6 +132,13 @@ func (s *subRPCServerConfigs) PopulateDependencies(cc *chainControl,
 				reflect.ValueOf(cc.chainNotifier),
 			)
 
+		case *invoicesrpc.Config:
+			subCfgValue := extractReflectValue(cfg)
+
+			subCfgValue.FieldByName("InvoiceRegistry").Set(
+				reflect.ValueOf(invoiceRegistry),
+			)
+
 		default:
 			return fmt.Errorf("unknown field: %v, %T", fieldName,
 				cfg)