module Ramaze::Helper::Cache

Caching of simple objects and whole action responses.

Public Class Methods

included(into) click to toggle source

Setup needed traits, add the singleton methods and add the caches used by this helper.

@param [Class] into Class that this Module is included into @author manveru

# File lib/ramaze/helper/cache.rb, line 16
def self.included(into)
  into.extend(SingletonMethods)
  into.add_action_wrapper(6.0, :cache_wrap)
  into.trait[:cache_action] ||= Set.new
  Ramaze::Cache.add(:action, :cache_helper_value)
end

Public Instance Methods

cache_value(key = nil, options = {}) { || ... } click to toggle source

This method is used to access Ramaze::Cache.cache_helper_value. It provides an easy way to cache long-running computations, gathering external resources like RSS feeds or DB queries that are the same for every user of an application. This method changes behaviour if a block is passed, which can be used to do lazy computation of the cached value conveniently when using a custom TTL or longer expressions that don't fit on one line with ||=.

@example to get the cache object directly

count = cache_value[:count] ||= Article.count

@example with block

count = cache_value(:count){ Article.count }
count = cache_value(:count, :ttl => 60){ Article.count }

@return [Object] The cache wrapper assigned for :cache_helper_value @see Innate::Cache @author manveru

# File lib/ramaze/helper/cache.rb, line 86
def cache_value(key = nil, options = {})
  cache = Ramaze::Cache.cache_helper_value

  if key and block_given?
    if found = cache[key]
      found
    else
      cache.store(key, yield, options)
    end
  else
    cache
  end
end
cache_wrap(action) { || ... } click to toggle source

@param [Action] action The currently wrapped action @yield The next block in wrap_action_call @return [String] the response body @see Innate::Node#wrap_action_call @author manveru

# File lib/ramaze/helper/cache.rb, line 30
def cache_wrap(action)
  cache = Innate::Cache.action

  ancestral_trait[:cache_action].each do |cache_action|
    temp  = cache_action.dup
    block = temp.delete(:key)
    ttl   = temp.delete(:ttl)

    if temp.all?{|key, value| action[key] == value }
      cache_key = action.full_path
      cache_key << "_#{action.instance.instance_eval(&block).to_s}" if block

      if cached = cache[cache_key]
        action.options[:content_type] = cached[:type]
      else
        cached = {
          :body => catch(:respond) { yield },
          :type => response['Content-Type']
        }

        if ttl
          cache.store(cache_key, cached, :ttl => ttl)
        else
          cache.store(cache_key, cached)
        end
      end

      return cached[:body]
    end
  end

  yield
end