require 'uri' require 'rack/cache/metastore' require 'rack/cache/entitystore' module Rack::Cache # Maintains a collection of MetaStore and EntityStore instances keyed by # URI. A single instance of this class can be used across a single process # to ensure that only a single instance of a backing store is created per # unique storage URI. class Storage def initialize @metastores = {} @entitystores = {} end def resolve_metastore_uri(uri) @metastores[uri.to_s] ||= create_store(MetaStore, uri) end def resolve_entitystore_uri(uri) @entitystores[uri.to_s] ||= create_store(EntityStore, uri) end def clear @metastores.clear @entitystores.clear nil end private def create_store(type, uri) if uri.respond_to?(:scheme) || uri.respond_to?(:to_str) uri = URI.parse(uri) unless uri.respond_to?(:scheme) if type.const_defined?(uri.scheme.upcase) klass = type.const_get(uri.scheme.upcase) klass.resolve(uri) else fail "Unknown storage provider: #{uri.to_s}" end else # hack in support for passing a Dalli::Client or Memcached object # as the storage URI. case when defined?(::Dalli) && uri.kind_of?(::Dalli::Client) type.const_get(:Dalli).resolve(uri) when defined?(::Memcached) && uri.respond_to?(:stats) type.const_get(:MemCached).resolve(uri) else fail "Unknown storage provider: #{uri.to_s}" end end end public @@singleton_instance = new def self.instance @@singleton_instance end end end