Module: ActsAsQueue::ClassMethods

Defined in:
lib/acts_as_queue.rb

Overview

acts_as_queue allows you to turn any ActiveRecord model into a queue, providing you with the necessary actions to manipulate your model. The class also allows you to define a queue size so that your queue can then become a bounded queue.

acts_as_queue example

class Post < ActiveRecord::Base
   acts_as_queue
end

# Pushing new posts onto the queue.
Post.push :name => "Hello World"
Post.push :name => "Using Rails"

# Popping the item at the front of the queue.
Post.pop

Instance Method Summary collapse

Instance Method Details

#acts_as_queue(options = {}) ⇒ Object

Configuration options are:

size - specifies the bounded queue size. Example: acts_as_queue :size => 20



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# File 'lib/acts_as_queue.rb', line 28

def acts_as_queue(options = {})
  configuration = { :size => "0" }
  configuration.update(options) if options.is_a?(Hash)
  
  class_eval "    \n    def self.queue_size\n      '\#{configuration[:size]}'.to_i\n    end\n  EOV\nend\n"

#count ⇒ Object

Returns the number of items in the queue.



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# File 'lib/acts_as_queue.rb', line 57

def count
  self.find(:all).count
end

#pop ⇒ Object

Pops the earliest item from the queue.



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# File 'lib/acts_as_queue.rb', line 50

def pop
  attributes = self.first.attributes
  self.first.delete
  attributes.inject({}) { |attribute,(k,v)| attribute[k.to_sym] = v; attribute } 
end

#push(attributes) ⇒ Object

Pushes an item onto the queue.



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# File 'lib/acts_as_queue.rb', line 41

def push(attributes)
  if (self.queue_size > 0) && (self.count == self.queue_size)
    popped = self.pop
  end
  
  self.create(attributes)   
end