gistfile1.rb

class Job < CouchRestBase
  include Delayed::Backend::Base
  use_database :delayed_job
  
  property :priority
  property :attempts
  property :handler
  property :run_at
  property :locked_at
  property :locked_by
  property :failed_at
  property :last_error
  timestamps!

  view_by :locked_by
  view_by(:locked_at, :run_at,
          :map => "function(doc){" +
          "          if(doc['couchrest-type'] == 'Job' && doc.run_at) {" +
          "            var locked_at = doc.locked_at || '';" +
          "            emit([locked_at, doc.run_at], null);}" +
          "        }")

  set_callback :save, :before, :set_default_run_at

  def self.db_time_now; Time.now; end
  def self.find id; get id; end    
  def self.find_available(worker_name, limit = 5, max_run_time = Worker.max_run_time)
    by_locked_at_and_run_at :start_key => [''], :end_key => ['', db_time_now], :limit => limit
  end
  def self.clear_locks!(worker_name)
    docs = by_locked_by :startkey => [worker_name], :endkey => [worker_name, {}]
    docs.each { |doc| doc.locked_by, doc.locked_at = nil, nil; }
    database.bulk_save docs
  end
  def self.delete_all
    database.recreate!
  end
  
  def lock_exclusively!(max_run_time, worker = worker_name)
    locked_at, locked_by = self.class.db_time_now, worker
    save
  end
end