class ActionDispatch::Request::Session::Options

def self.find(req)
  req.get_header ENV_SESSION_OPTIONS_KEY
end

def self.set(req, options)
  req.set_header ENV_SESSION_OPTIONS_KEY, options
end

def [](key)
  @delegate[key]
end

def []=(k, v);        @delegate[k] = v; end

def id(req)
  @delegate.fetch(:id) {
    @by.send(:extract_session_id, req)
  }
end

def initialize(by, default_options)
  @by       = by
  @delegate = default_options.dup
end

def to_hash;          @delegate.dup; end

def values_at(*args); @delegate.values_at(*args); end