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# app/models/queue/base.rb
class Queue::Base

  class << self

    def enqueue(object, method, *args)
      # ...to be continued
    end

    def perform

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Resque.redis = Redis::Namespace.new(:resque, :redis => $redis)

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# app/models/queue/high.rb
class Queue::High
  @queue = :high
  
  def self.enqueue(object, method, *args)
    # ...to be continued
  end

  def self.perform
    # ...to be continued

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COUNT=3 QUEUE=high,normal,low rake resque:workers

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# app/controller/posts_controller.rb
class PostsController < ApplicationController
  
  before_filter :find_post
  
  protected
    
    def find_post
      if id = Slug[params[:id]]
         @post = Post.find(id)

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Post.find_each { |post| Slug[post.id.to_s] = post.id.to_s }

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# app/models/post.rb
class Post < ActiveRecord::Base
  
  validate :ensure_slug_uniqueness
  
  protected
  
    # validate
    def ensure_slug_uniqueness
      

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class PostObserver
  def after_save(post)
    Slug[post.slug] = post.id
    return true
  end
  
  def after_destroy(post)
    Slug.destroy(post.id)
    return true
  end

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class Slug
  class << self
    
    def [](slug)
      redis.hget(hash, slug)
    end
    
    def []=(slug, id)
      if old = self[slug]
        redis.srem(set(old), slug)

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class Slug
  class << self
    
    def [](slug)
      redis.hget(hash, slug)
    end
    
    def []=(slug, id)
      if old = self[slug]
        redis.srem(set(old), slug)