SidekiqSidekiq

# Gemfile
# gem 'sidekiq'

# config/sidekiq.yml
:concurrency: 10
:queues:
  - [critical, 3]  # 가중치 3 (더 자주 처리)
  - [default, 2]
  - [low, 1]

# app/workers/email_worker.rb
class EmailWorker
  include Sidekiq::Worker

  sidekiq_options(
    queue: :default,
    retry: 5,
    dead: false  # 최종 실패 시 DLQ에 넣지 않음
  )

  def perform(user_id, template)
    user = User.find(user_id)
    UserMailer.send_template(user, template).deliver_now
  end
end

# 잡 큐에 추가
EmailWorker.perform_async(user.id, 'welcome')         # 즉시
EmailWorker.perform_in(5.minutes, user.id, 'reminder') # 5분 후
EmailWorker.perform_at(Date.tomorrow.noon, user.id, 'digest') # 특정 시각

# Batch (여러 잡 일괄 처리 + 콜백)
batch = Sidekiq::Batch.new
batch.description = "사용자 일괄 처리"
batch.on(:success, BatchCallbacks, user_ids: [1, 2, 3])
batch.jobs do
  [1, 2, 3].each { |id| ProcessUserWorker.perform_async(id) }
end

# Rate Limiting (처리율 제한)
class ApiCallWorker
  include Sidekiq::Worker
  sidekiq_options limiter: {
    name: 'external_api',
    limit: 100,
    period: 60  # 분당 100회
  }
  def perform(endpoint); end
end

# Periodic Jobs (스케줄)
Sidekiq::Cron::Job.create(
  name: 'Daily Report',
  cron: '0 9 * * *',  # 매일 오전 9시
  class: 'DailyReportWorker'
)