Munna

Simple cache wrapper for rails ActiveRecord, Object, ... to speed up your site

Installation

Add this line to your application's Gemfile:

gem 'munna'

Usage

ActiveRecord

class Profile < ActiveRecord::Base
  after_destroy :clear_cache

  def clear_cache
    User.delete_cached :list_with_profiles
  end
end

class User < ActiveRecord::Base
  has_many :profiles

  def self.list_with_profiles
    cached {
      join(:profiles)
      .group('users.id')
      .select('users.*, count(users.id)')
    }
  end

  # get random 5 rows, cache for 10.hours
  def self.list_by_random
    cached_for 10.hours {
      order('rand(id)').limit(5)
    }
  end
end

User.cached.all # get all users at the first time, after that fetch from cache

Advanced Options

Everything in rails can be cached through cached, cached_for and remove through delete_cached

1. cached vs delete_cached

cached	delete_cached
Anything.cached(opts).function	Anything.delete_cached.function
Anything.cached(:name, opts).function	Anything.delete_cached :name
Anything.cached([:name, :id], opts).function	Anything.delete_cached [:name, :id]
Anything.cached {}	Anything.delete_cached caller_name
Anything.cached(:name, opts) { ... }	Anything.delete_cached :name
Anything.cached([:name, :id], opts) { ... }	Anything.delete_cached [:name, :id]

2. cached_for: is the quite similar to cached, with shortcut for expires_in

Anything.cached_for(10.hours, opts).function
Anything.cached_for(10.hours, opts) {}

• opts is optional, you can ignore it
• caller_name is the function name that line belong to

3. opts: is a Hash, has options

• expires_in: time to expire
• key: cached key for save and use for delete_cached

4. cache support

Munna.cache.values # => list all key in memcached
Munna.cache.clear # => clear all value, key in memcached
Munna.cache.get_matched /xxx/ # => get values with satify regex
Munna.cache.delete_matched /xxx/ # => delete values with satify regex