gitlab-org--gitlab-foss/lib/gitlab/daemon.rb
Kamil Trzciński cb193cd6b5 Improve resillency of monitor
- Retry connection when it fails
- Properly shutdown daemon
- Stop monitor if the Exception is raised
- Properly guard exception handling
2019-08-21 12:06:10 +02:00

68 lines
1.1 KiB
Ruby

# frozen_string_literal: true
module Gitlab
class Daemon
def self.initialize_instance(*args)
raise "#{name} singleton instance already initialized" if @instance
@instance = new(*args)
Kernel.at_exit(&@instance.method(:stop))
@instance
end
def self.instance
@instance ||= initialize_instance
end
attr_reader :thread
def thread?
!thread.nil?
end
def initialize
@mutex = Mutex.new
end
def enabled?
true
end
def start
return unless enabled?
@mutex.synchronize do
break thread if thread?
@thread = Thread.new { start_working }
end
end
def stop
@mutex.synchronize do
break unless thread?
stop_working
if thread
thread.wakeup if thread.alive?
begin
thread.join unless Thread.current == thread
rescue Exception # rubocop:disable Lint/RescueException
end
@thread = nil
end
end
end
private
def start_working
raise NotImplementedError
end
def stop_working
# no-ops
end
end
end