Question

延迟::工作序列化你的班级，方法＆amp;参数进入处理程序字段。我们目前正在将这种序列化方法硬编码到我们的代码中。这很糟糕。

我们应该如何构建处理程序，以便查找现有的排队作业？

Answer 1

我这样做：

1）向delayed_jobs表格

添加两个新列

分贝/迁移/ 20110906004963_add_owner_to_delayed_jobs.rb

class AddOwnerToDelayedJobs < ActiveRecord::Migration
  def self.up
    add_column :delayed_jobs, :owner_type, :string
    add_column :delayed_jobs, :owner_id, :integer

    add_index :delayed_jobs, [:owner_type, :owner_id]
  end

  def self.down
    remove_column :delayed_jobs, :owner_type
    remove_column :delayed_jobs, :owner_id
  end
end

2）向Delayed::Job模型

添加多态关联

配置/初始化/ delayed_job.rb

class Delayed::Job < ActiveRecord::Base
  belongs_to :owner, :polymorphic => true
  attr_accessible :owner, :owner_type, :owner_id
end

3）猴子补丁ActiveRecord::Base包含职位关联

配置/初始化/ active_record.rb

class ActiveRecord::Base
  has_many :jobs, :class_name => "Delayed::Job", :as => :owner
  def send_at(time, method, *args)
    Delayed::Job.transaction do
      job = Delayed::Job.enqueue(Delayed::PerformableMethod.new(self, 
             method.to_sym, args), 10, time)
      job.owner = self
      job.save
    end
  end

  def self.jobs
    # to address the STI scenario we use base_class.name. 
    # downside: you have to write extra code to filter STI class specific instance.
    Delayed::Job.find_all_by_owner_type(self.base_class.name)
  end
end

4）触发工作

class Order < ActiveRecord::Base

  after_create :set_reminders

  def set_reminders
    send_at(2.days.from_now, :send_email_reminder)
  end

  def send_email_reminder
  end

  # setting owner for handle_asynchronously notation.
  def foo
  end
  handle_asynchronously :foo, :owner => Proc.new { |o| o  }

end

5）检查工作

Order.jobs  # lists all the running jobs for Order class
order1.jobs # lists all the running jobs for Order object order1

如何找到特定的延迟作业（不是id）？

1 个答案: