From 55013c3d0d8ef9166641d75adc6259181ab7878c Mon Sep 17 00:00:00 2001
From: jkoberg <jkoberg@owncloud.com>
Date: Tue, 17 Oct 2023 15:32:14 +0200
Subject: [PATCH] start nats before other services

Signed-off-by: jkoberg <jkoberg@owncloud.com>
---
 ocis/pkg/runtime/service/service.go | 34 ++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/ocis/pkg/runtime/service/service.go b/ocis/pkg/runtime/service/service.go
index ed5918584..3b421497c 100644
--- a/ocis/pkg/runtime/service/service.go
+++ b/ocis/pkg/runtime/service/service.go
@@ -71,6 +71,7 @@ type serviceFuncMap map[string]func(*ociscfg.Config) suture.Service
 // Service represents a RPC service.
 type Service struct {
 	Supervisor       *suture.Supervisor
+	Preliminary      serviceFuncMap
 	ServicesRegistry serviceFuncMap
 	Delayed          serviceFuncMap
 	Additional       serviceFuncMap
@@ -103,6 +104,7 @@ func NewService(options ...Option) (*Service, error) {
 	globalCtx, cancelGlobal := context.WithCancel(context.Background())
 
 	s := &Service{
+		Preliminary:      make(serviceFuncMap),
 		ServicesRegistry: make(serviceFuncMap),
 		Delayed:          make(serviceFuncMap),
 		Additional:       make(serviceFuncMap),
@@ -114,6 +116,13 @@ func NewService(options ...Option) (*Service, error) {
 		cfg:          opts.Config,
 	}
 
+	// start nats first - it is used as service registry
+	s.Preliminary[opts.Config.Nats.Service.Name] = NewSutureServiceBuilder(func(ctx context.Context, cfg *ociscfg.Config) error {
+		cfg.Nats.Context = ctx
+		cfg.Nats.Commons = cfg.Commons
+		return nats.Execute(cfg.Nats)
+	})
+
 	// populate services
 	reg := func(name string, exec func(context.Context, *ociscfg.Config) error) {
 		s.ServicesRegistry[name] = NewSutureServiceBuilder(exec)
@@ -183,11 +192,6 @@ func NewService(options ...Option) (*Service, error) {
 		cfg.Invitations.Commons = cfg.Commons
 		return invitations.Execute(cfg.Invitations)
 	})
-	reg(opts.Config.Nats.Service.Name, func(ctx context.Context, cfg *ociscfg.Config) error {
-		cfg.Nats.Context = ctx
-		cfg.Nats.Commons = cfg.Commons
-		return nats.Execute(cfg.Nats)
-	})
 	reg(opts.Config.Notifications.Service.Name, func(ctx context.Context, cfg *ociscfg.Config) error {
 		cfg.Notifications.Context = ctx
 		cfg.Notifications.Commons = cfg.Commons
@@ -394,11 +398,8 @@ func Start(o ...Option) error {
 	// prepare the set of services to run
 	s.generateRunSet(s.cfg)
 
-	// schedule services that we are sure don't have interdependencies.
-	scheduleServiceTokens(s, s.ServicesRegistry)
-
-	// schedule services that are optional
-	scheduleServiceTokens(s, s.Additional)
+	// schedule preliminary services first
+	scheduleServiceTokens(s, s.Preliminary)
 
 	// there are reasons not to do this, but we have race conditions ourselves. Until we resolve them, mind the following disclaimer:
 	// Calling ServeBackground will CORRECTLY start the supervisor running in a new goroutine. It is risky to directly run
@@ -410,6 +411,15 @@ func Start(o ...Option) error {
 	// trap will block on halt channel for interruptions.
 	go trap(s, halt)
 
+	// grace period for supervisor to get up
+	time.Sleep(time.Second)
+
+	// schedule services that we are sure don't have interdependencies.
+	scheduleServiceTokens(s, s.ServicesRegistry)
+
+	// schedule services that are optional
+	scheduleServiceTokens(s, s.Additional)
+
 	// add services with delayed execution.
 	time.Sleep(1 * time.Second)
 	scheduleServiceTokens(s, s.Delayed)
@@ -440,6 +450,10 @@ func (s *Service) generateRunSet(cfg *ociscfg.Config) {
 		return
 	}
 
+	for name := range s.Preliminary {
+		runset[name] = struct{}{}
+	}
+
 	for name := range s.ServicesRegistry {
 		runset[name] = struct{}{}
 	}