add race delay for existing connections during startup

NTFServer.go

@@ -110,6 +110,7 @@ func NewNTFServer(configFile string, verbose bool) (*NTFServer, error) {
 	}
 
 	// Spawn upstream connections for all pre-existing known users
+	launchedAny := false
 	for telegramUserId, telegramDisplayName := range ret.config.GroupChatMembers {
 		hubNick, ok := ret.config.KnownUsers[telegramUserId]
 		if !ok {
@@ -120,6 +121,14 @@ func NewNTFServer(configFile string, verbose bool) (*NTFServer, error) {
 		if err != nil {
 			return nil, fmt.Errorf("Reconnecting upstream for '%s': %s", hubNick, err.Error()) // fatal
 		}
+
+		launchedAny = true
+	}
+
+	// We have some bad edge cases if a telegram message comes in while the upstream
+	// connection is offline. Wait a bit after startup, to minimise failure cases
+	if launchedAny {
+		time.Sleep(5 * time.Second)
 	}
 
 	return &ret, nil