gistfile1.rb

class NotificationCluster < ActiveRecord::Base
  CLUSTER_TIMEOUT = 30.seconds
  serialize :associated_files			# an array of file ids

  scope :unsent, :conditions => {:delivered => false}
  scope :within_the_last, lambda {|secs|
    {:conditions => ["created_at >= ?", secs.ago]}
  }

  scope :for, lambda{|arguments|
    # add some more conditions here. 
  }

  def self.find_or_create_for(*args)
    # Find an existing NotificationCluster object for the given args,
    # or create a new one.
    n = unsent.within_the_last(CLUSTER_TIMEOUT).for(*args).first
    n ||= new_for(*args)
  end

  def self.new_for(*args)
    # build a new NotificationCluster object here
  end

  def enqueue!
    # First, remove any existing enqueued jobs for this action so we can have events that
    # are ongoing
    Resque.remove_delayed(NotificationSendingJob, self.id)
    
    # Then set another time for x seconds from now.
    # if there's an event in between now and x seconds, then this job will be replaced 
    # with a new scheduled job
    Resque.enqueue_at(CLUSTER_TIMEOUT.from_now, NotificationSendingJob, self.id)
  end
end