rufus-scheduler 수정

app/services/modbus/polling_service.rb

@@ -5,10 +5,10 @@ module Modbus
   class PollingService
     class << self
       def start
-        return if defined?(@scheduler) && @scheduler.jobs.any?
+        return if @scheduler && @scheduler.jobs.any?
 
         puts "[#{Time.current}] Modbus polling service 시작됨 (Rufus)"
-        @scheduler = Rufus::Scheduler.new
+        @scheduler ||= Rufus::Scheduler.new
 
         @scheduler.cron "0 * * * * *" do
           now = Time.now
@@ -22,6 +22,7 @@ module Modbus
       def stop
         if defined?(@scheduler)
           @scheduler.shutdown(:kill)
+          @scheduler = nil
           puts "[#{Time.current}] Modbus polling service 중지됨"
         else
           puts "[#{Time.current}] Scheduler 인스턴스 없음"
@@ -29,7 +30,7 @@ module Modbus
       end
 
       def running?
-        defined?(@scheduler) && @scheduler.jobs.any?
+        @scheduler && @scheduler.jobs.any?
       end
 
       private