From 46857a747891fe5360b1f0805d0dc58705dff6ee Mon Sep 17 00:00:00 2001
From: atauov <atauov@gmail.com>
Date: Thu, 13 Nov 2025 17:54:41 +0500
Subject: [PATCH 1/2] add retries for NATS connect

---
 statefun/runtime.go | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/statefun/runtime.go b/statefun/runtime.go
index b544a56..f014269 100644
--- a/statefun/runtime.go
+++ b/statefun/runtime.go
@@ -52,17 +52,30 @@ func NewRuntime(config RuntimeConfig) (*Runtime, error) {
 		shutdown:                   make(chan struct{}),
 	}
 
-	var err error
+	natsOpts := nats.GetDefaultOptions()
+	natsOpts.Url = r.config.natsURL
+	natsOpts.MaxReconnect = -1 // -1 - infinity attempts
+	natsOpts.ReconnectedCB = func(nc *nats.Conn) {
+		lg.GetLogger().Warnf(context.TODO(), "NATS reconnected %d times", nc.Statistics.Reconnects)
+	}
 
 	if r.config.enableTLS {
-		opts := []nats.Option{
-			nats.Secure(&tls.Config{InsecureSkipVerify: true}), // for self-assigned certificates
-		}
-		r.nc, err = nats.Connect(config.natsURL, opts...)
-	} else {
-		r.nc, err = nats.Connect(config.natsURL)
+		natsOpts.Secure = true
+		natsOpts.TLSConfig = &tls.Config{InsecureSkipVerify: true}
 	}
 
+	var err error
+	maxAttempts := system.GetEnvMustProceed("RETRIES_NATS_CONNECT", 10)
+	for attempt := 1; attempt <= maxAttempts; attempt++ {
+		r.nc, err = natsOpts.Connect()
+		if err != nil && attempt < maxAttempts {
+			lg.GetLogger().Errorf(context.TODO(), "Can't connect to NATS at attempt %d/%d: %v", attempt, maxAttempts, err)
+			// Linear backoff: increase delay by 1 second on each attempt
+			time.Sleep(time.Duration(1+attempt) * time.Second)
+		} else {
+			break
+		}
+	}
 	if err != nil {
 		return nil, err
 	}

From c42fbe5e8811fbc06c67bf6f75f6b98cea5cf8cd Mon Sep 17 00:00:00 2001
From: atauov <atauov@gmail.com>
Date: Thu, 13 Nov 2025 17:56:13 +0500
Subject: [PATCH 2/2] comment

---
 statefun/runtime.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/statefun/runtime.go b/statefun/runtime.go
index f014269..abb45dd 100644
--- a/statefun/runtime.go
+++ b/statefun/runtime.go
@@ -61,7 +61,7 @@ func NewRuntime(config RuntimeConfig) (*Runtime, error) {
 
 	if r.config.enableTLS {
 		natsOpts.Secure = true
-		natsOpts.TLSConfig = &tls.Config{InsecureSkipVerify: true}
+		natsOpts.TLSConfig = &tls.Config{InsecureSkipVerify: true} // for self-assigned certificates
 	}
 
 	var err error