invoicesrpc: add settlement interceptor to invoices RPC server

This commit integrates the settlement interceptor service into the
invoices RPC server.

lnd.go

@@ -630,7 +630,8 @@ func Main(cfg *Config, lisCfg ListenerCfg, implCfg *ImplementationCfg,
 	// RPC server as well.
 	err = rpcServer.addDeps(
 		server, interceptorChain.MacaroonService(), cfg.SubRPCServers,
-		atplManager, server.invoices, tower, multiAcceptor,
+		atplManager, server.invoices,
+		server.invoiceSettlementInterceptor, tower, multiAcceptor,
 	)
 	if err != nil {
 		return mkErr("unable to add deps to RPC server: %v", err)

lnrpc/invoicesrpc/config_active.go

@@ -30,6 +30,11 @@ type Config struct {
 	// created by the daemon.
 	InvoiceRegistry *invoices.InvoiceRegistry
 
+	// InvoiceSettlementInterceptor is a service which intercepts invoices
+	// during the settlement phase, enabling a subscribed client to
+	// determine the settlement outcome.
+	InvoiceSettlementInterceptor invoices.SettlementInterceptorInterface
+
 	// IsChannelActive is used to generate valid hop hints.
 	IsChannelActive func(chanID lnwire.ChannelID) bool
 

rpcserver.go

@@ -672,7 +672,9 @@ func newRPCServer(cfg *Config, interceptorChain *rpcperms.InterceptorChain,
 // be started, and start accepting RPC calls.
 func (r *rpcServer) addDeps(s *server, macService *macaroons.Service,
 	subServerCgs *subRPCServerConfigs, atpl *autopilot.Manager,
-	invoiceRegistry *invoices.InvoiceRegistry, tower *watchtower.Standalone,
+	invoiceRegistry *invoices.InvoiceRegistry,
+	invoiceSettlementInterceptor *invoices.SettlementInterceptor,
+	tower *watchtower.Standalone,
 	chanPredicate chanacceptor.MultiplexAcceptor) error {
 
 	// Set up router rpc backend.
@@ -771,12 +773,13 @@ func (r *rpcServer) addDeps(s *server, macService *macaroons.Service,
 	// TODO(roasbeef): extend sub-sever config to have both (local vs remote) DB
 	err = subServerCgs.PopulateDependencies(
 		r.cfg, s.cc, r.cfg.networkDir, macService, atpl, invoiceRegistry,
-		s.htlcSwitch, r.cfg.ActiveNetParams.Params, s.chanRouter,
-		routerBackend, s.nodeSigner, s.graphDB, s.chanStateDB,
-		s.sweeper, tower, s.towerClientMgr, r.cfg.net.ResolveTCPAddr,
-		genInvoiceFeatures, genAmpInvoiceFeatures,
-		s.getNodeAnnouncement, s.updateAndBrodcastSelfNode, parseAddr,
-		rpcsLog, s.aliasMgr.GetPeerAlias,
+		invoiceSettlementInterceptor, s.htlcSwitch,
+		r.cfg.ActiveNetParams.Params, s.chanRouter, routerBackend,
+		s.nodeSigner, s.graphDB, s.chanStateDB, s.sweeper, tower,
+		s.towerClientMgr, r.cfg.net.ResolveTCPAddr, genInvoiceFeatures,
+		genAmpInvoiceFeatures, s.getNodeAnnouncement,
+		s.updateAndBrodcastSelfNode, parseAddr, rpcsLog,
+		s.aliasMgr.GetPeerAlias,
 	)
 	if err != nil {
 		return err

subrpcserver_config.go

@@ -104,6 +104,7 @@ func (s *subRPCServerConfigs) PopulateDependencies(cfg *Config,
 	networkDir string, macService *macaroons.Service,
 	atpl *autopilot.Manager,
 	invoiceRegistry *invoices.InvoiceRegistry,
+	invoiceSettlementInterceptor *invoices.SettlementInterceptor,
 	htlcSwitch *htlcswitch.Switch,
 	activeNetParams *chaincfg.Params,
 	chanRouter *routing.ChannelRouter,
@@ -238,6 +239,10 @@ func (s *subRPCServerConfigs) PopulateDependencies(cfg *Config,
 			subCfgValue.FieldByName("InvoiceRegistry").Set(
 				reflect.ValueOf(invoiceRegistry),
 			)
+			//nolint:lll
+			subCfgValue.FieldByName("InvoiceSettlementInterceptor").Set(
+				reflect.ValueOf(invoiceSettlementInterceptor),
+			)
 			subCfgValue.FieldByName("IsChannelActive").Set(
 				reflect.ValueOf(htlcSwitch.HasActiveLink),
 			)