# module ActiveSupport::Cache

See ActiveSupport::Cache::Store for documentation.

### Constants

UNIVERSAL_OPTIONS

  These options mean something to all cache implementations. Individual cache implementations may support additional options.

### Public Class Methods

expand_cache_key(key, namespace = nil) click to toggle source

    # File lib/active_support/cache.rb, line 77
    def expand_cache_key(key, namespace = nil)
      expanded_cache_key = namespace ? "#{namespace}/" : ""

      if prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
        expanded_cache_key << "#{prefix}/"
      end

      expanded_cache_key << retrieve_cache_key(key)
      expanded_cache_key
    end

lookup_store(*store_option) click to toggle source

Creates a new CacheStore object according to the given options.

If no arguments are passed to this method, then a new ActiveSupport::Cache::MemoryStore object will be returned.

If you pass a Symbol as the first argument, then a corresponding cache store class under the ActiveSupport::Cache namespace will be created. For example:

    ActiveSupport::Cache.lookup_store(:memory_store)
    # => returns a new ActiveSupport::Cache::MemoryStore object

    ActiveSupport::Cache.lookup_store(:mem_cache_store)
    # => returns a new ActiveSupport::Cache::MemCacheStore object

Any additional arguments will be passed to the corresponding cache store class’s constructor:

    ActiveSupport::Cache.lookup_store(:file_store, "/tmp/cache")
    # => same as: ActiveSupport::Cache::FileStore.new("/tmp/cache")

If the first argument is not a Symbol, then it will simply be returned:

    ActiveSupport::Cache.lookup_store(MyOwnCacheStore.new)
    # => returns MyOwnCacheStore.new

    # File lib/active_support/cache.rb, line 55
    def lookup_store(*store_option)
      store, *parameters = *Array.wrap(store_option).flatten

      case store
      when Symbol
        store_class_name = store.to_s.camelize
        store_class =
          begin
            require "active_support/cache/#{store}"
          rescue LoadError => e
            raise "Could not find cache store adapter for #{store} (#{e})"
          else
            ActiveSupport::Cache.const_get(store_class_name)
          end
        store_class.new(*parameters)
      when nil
        ActiveSupport::Cache::MemoryStore.new
      else
        store
      end
    end