From 74485d3b13b4dd4aeca652e6a042846891253dfd Mon Sep 17 00:00:00 2001
From: Mikhail Bragin <bangvalo@gmail.com>
Date: Mon, 18 Oct 2021 13:29:26 +0200
Subject: [PATCH] fix: service hanging when error on startup has been
 encountered (#135)

---
 client/cmd/service_controller.go | 28 ++++++++++++++++++++++++++--
 management/client/client.go      |  2 +-
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/client/cmd/service_controller.go b/client/cmd/service_controller.go
index 816325907..ca20b4842 100644
--- a/client/cmd/service_controller.go
+++ b/client/cmd/service_controller.go
@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"github.com/cenkalti/backoff/v4"
 	"github.com/kardianos/service"
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -9,11 +10,32 @@ import (
 )
 
 func (p *program) Start(s service.Service) error {
+
+	var backOff = &backoff.ExponentialBackOff{
+		InitialInterval:     time.Second,
+		RandomizationFactor: backoff.DefaultRandomizationFactor,
+		Multiplier:          backoff.DefaultMultiplier,
+		MaxInterval:         30 * time.Second,
+		MaxElapsedTime:      24 * 3 * time.Hour, //stop after 3 days trying
+		Stop:                backoff.Stop,
+		Clock:               backoff.SystemClock,
+	}
+
 	// Start should not block. Do the actual work async.
 	log.Info("starting service") //nolint
 	go func() {
-		err := runClient()
+		operation := func() error {
+			err := runClient()
+			if err != nil {
+				log.Warnf("retrying Wiretrustee client app due to error: %v", err)
+				return err
+			}
+			return nil
+		}
+
+		err := backoff.Retry(operation, backOff)
 		if err != nil {
+			log.Errorf("exiting client retry loop due to unrecoverable error: %s", err)
 			return
 		}
 	}()
@@ -21,7 +43,9 @@ func (p *program) Start(s service.Service) error {
 }
 
 func (p *program) Stop(s service.Service) error {
-	stopCh <- 1
+	go func() {
+		stopCh <- 1
+	}()
 
 	select {
 	case <-cleanupCh:
diff --git a/management/client/client.go b/management/client/client.go
index 6d1c96f9e..902278bb4 100644
--- a/management/client/client.go
+++ b/management/client/client.go
@@ -45,7 +45,7 @@ func NewClient(ctx context.Context, addr string, ourPrivateKey wgtypes.Key, tlsE
 		}))
 
 	if err != nil {
-		log.Errorf("failed creating connection to Management Srvice %v", err)
+		log.Errorf("failed creating connection to Management Service %v", err)
 		return nil, err
 	}