From 3f0a0e6f9cf9e5963d89c6d1be515d8f43ee08bb Mon Sep 17 00:00:00 2001
From: Sebastien Douheret <sebastien.douheret@iot.bzh>
Date: Thu, 24 Aug 2017 21:45:32 +0200
Subject: [PATCH] Take care of ST connection lost in ST event monitor.

---
 lib/syncthing/st.go      | 16 ++++++++++------
 lib/syncthing/stEvent.go | 23 +++++++++++++++++++++++
 2 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/lib/syncthing/st.go b/lib/syncthing/st.go
index b622970..5086994 100644
--- a/lib/syncthing/st.go
+++ b/lib/syncthing/st.go
@@ -27,12 +27,13 @@ import (
 
 // SyncThing .
 type SyncThing struct {
-	BaseURL string
-	APIKey  string
-	Home    string
-	STCmd   *exec.Cmd
-	STICmd  *exec.Cmd
-	MyID    string
+	BaseURL   string
+	APIKey    string
+	Home      string
+	STCmd     *exec.Cmd
+	STICmd    *exec.Cmd
+	MyID      string
+	Connected bool
 
 	// Private fields
 	binDir      string
@@ -301,6 +302,7 @@ func (s *SyncThing) StopInotify() {
 // Connect Establish HTTP connection with Syncthing
 func (s *SyncThing) Connect() error {
 	var err error
+	s.Connected = false
 	s.client, err = common.HTTPNewClient(s.BaseURL,
 		common.HTTPClientConfig{
 			URLPrefix:           "/rest",
@@ -327,6 +329,8 @@ func (s *SyncThing) Connect() error {
 		return fmt.Errorf("ERROR: cannot retrieve ID")
 	}
 
+	s.Connected = true
+
 	// Start events monitoring
 	err = s.Events.Start()
 
diff --git a/lib/syncthing/stEvent.go b/lib/syncthing/stEvent.go
index bf2a809..9ca8b78 100644
--- a/lib/syncthing/stEvent.go
+++ b/lib/syncthing/stEvent.go
@@ -148,6 +148,8 @@ func (e *Events) getEvents(since int) ([]STEvent, error) {
 func (e *Events) monitorLoop() {
 	e.log.Infof("Event monitoring running...")
 	since := 0
+	cntErrConn := 0
+	cntErrRetry := 1
 	for {
 		select {
 		case <-e.stop:
@@ -155,11 +157,32 @@ func (e *Events) monitorLoop() {
 			return
 
 		case <-time.After(e.MonitorTime * time.Millisecond):
+
+			if !e.st.Connected {
+				cntErrConn++
+				time.Sleep(time.Second)
+				if cntErrConn > cntErrRetry {
+					e.log.Error("ST Event monitor: ST connection down")
+					cntErrConn = 0
+					cntErrRetry *= 2
+					if _, err := e.getEvents(since); err == nil {
+						e.st.Connected = true
+						cntErrRetry = 1
+						// XXX - should we reset since value ?
+						goto readEvent
+					}
+				}
+				continue
+			}
+
+		readEvent:
 			stEvArr, err := e.getEvents(since)
 			if err != nil {
 				e.log.Errorf("Syncthing Get Events: %v", err)
+				e.st.Connected = false
 				continue
 			}
+
 			// Process events
 			for _, stEv := range stEvArr {
 				since = stEv.SubscriptionID
-- 
2.16.6