unified gateway interface

api/gateway/chain/internal/server/internal/serverimp.go

@@ -36,6 +36,7 @@ type Imp struct {
 	app    *grpcapp.App[storage.Repository]
 
 	rpcClients *rpcclient.Clients
+	service    *gatewayservice.Service
 }
 
 type config struct {
@@ -100,6 +101,10 @@ func (i *Imp) Shutdown() {
 		timeout = i.config.Runtime.ShutdownTimeout()
 	}
 
+	if i.service != nil {
+		i.service.Shutdown()
+	}
+
 	ctx, cancel := context.WithTimeout(context.Background(), timeout)
 	defer cancel()
 
@@ -151,7 +156,9 @@ func (i *Imp) Start() error {
 			gatewayservice.WithDriverRegistry(driverRegistry),
 			gatewayservice.WithSettings(cfg.Settings),
 		}
-		return gatewayservice.NewService(logger, repo, producer, opts...), nil
+		svc := gatewayservice.NewService(logger, repo, producer, opts...)
+		i.service = svc
+		return svc, nil
 	}
 
 	app, err := grpcapp.NewApp(i.logger, "chain", cfg.Config, i.debug, repoFactory, serviceFactory)

api/gateway/chain/internal/service/gateway/service.go

@@ -3,6 +3,7 @@ package gateway
 import (
 	"context"
 
+	"github.com/tech/sendico/gateway/chain/internal/appversion"
 	"github.com/tech/sendico/gateway/chain/internal/keymanager"
 	"github.com/tech/sendico/gateway/chain/internal/service/gateway/commands"
 	"github.com/tech/sendico/gateway/chain/internal/service/gateway/commands/transfer"
@@ -14,6 +15,7 @@ import (
 	"github.com/tech/sendico/pkg/api/routers"
 	"github.com/tech/sendico/pkg/api/routers/gsresponse"
 	clockpkg "github.com/tech/sendico/pkg/clock"
+	"github.com/tech/sendico/pkg/discovery"
 	msg "github.com/tech/sendico/pkg/messaging"
 	"github.com/tech/sendico/pkg/mlogger"
 	"github.com/tech/sendico/pkg/mservice"
@@ -47,6 +49,7 @@ type Service struct {
 	networkRegistry *rpcclient.Registry
 	drivers         *drivers.Registry
 	commands        commands.Registry
+	announcers      []*discovery.Announcer
 
 	chainv1.UnimplementedChainGatewayServiceServer
 }
@@ -83,6 +86,7 @@ func NewService(logger mlogger.Logger, repo storage.Repository, producer msg.Pro
 		Wallet:   commandsWalletDeps(svc),
 		Transfer: commandsTransferDeps(svc),
 	})
+	svc.startDiscoveryAnnouncers()
 
 	return svc
 }
@@ -94,6 +98,17 @@ func (s *Service) Register(router routers.GRPC) error {
 	})
 }
 
+func (s *Service) Shutdown() {
+	if s == nil {
+		return
+	}
+	for _, announcer := range s.announcers {
+		if announcer != nil {
+			announcer.Stop()
+		}
+	}
+}
+
 func (s *Service) CreateManagedWallet(ctx context.Context, req *chainv1.CreateManagedWalletRequest) (*chainv1.CreateManagedWalletResponse, error) {
 	return executeUnary(ctx, s, "CreateManagedWallet", s.commands.CreateManagedWallet.Execute, req)
 }
@@ -174,3 +189,29 @@ func executeUnary[TReq any, TResp any](ctx context.Context, svc *Service, method
 	observeRPC(method, err, svc.clock.Now().Sub(start))
 	return resp, err
 }
+
+func (s *Service) startDiscoveryAnnouncers() {
+	if s == nil || s.producer == nil || len(s.networks) == 0 {
+		return
+	}
+	version := appversion.Create().Short()
+	for _, network := range s.networks {
+		currencies := []string{shared.NativeCurrency(network)}
+		for _, token := range network.TokenConfigs {
+			if token.Symbol != "" {
+				currencies = append(currencies, token.Symbol)
+			}
+		}
+		announce := discovery.Announcement{
+			Service:    "CRYPTO_RAIL_GATEWAY",
+			Rail:       "CRYPTO",
+			Network:    network.Name,
+			Operations: []string{"balance.read", "payin.crypto", "payout.crypto", "fee.send"},
+			Currencies: currencies,
+			Version:    version,
+		}
+		announcer := discovery.NewAnnouncer(s.logger, s.producer, string(mservice.ChainGateway), announce)
+		announcer.Start()
+		s.announcers = append(s.announcers, announcer)
+	}
+}