class AWS::Core::ResourceCache

def cached?(key, attribute)
  attributes = @cache[key] and attributes.has_key?(attribute)
end

def get(key, attribute)
  raise "No cached value for attribute :#{attribute} of #{key}" unless
    cached?(key, attribute)
  @cache[key][attribute]
end

def initialize
  @cache = {}
end

def store(key, attributes)
  (@cache[key] ||= {}).merge!(attributes)
end