Current File : //opt/alt/ruby19/lib64/ruby/gems/1.9.1/gems/rack-1.6.4/lib/rack/session/abstract/id.rb
# AUTHOR: blink <blinketje@gmail.com>; blink#ruby-lang@irc.freenode.net
# bugrep: Andreas Zehnder
require 'time'
require 'rack/request'
require 'rack/response'
begin
require 'securerandom'
rescue LoadError
# We just won't get securerandom
end
module Rack
module Session
module Abstract
ENV_SESSION_KEY = 'rack.session'.freeze
ENV_SESSION_OPTIONS_KEY = 'rack.session.options'.freeze
# SessionHash is responsible to lazily load the session from store.
class SessionHash
include Enumerable
attr_writer :id
def self.find(env)
env[ENV_SESSION_KEY]
end
def self.set(env, session)
env[ENV_SESSION_KEY] = session
end
def self.set_options(env, options)
env[ENV_SESSION_OPTIONS_KEY] = options.dup
end
def initialize(store, env)
@store = store
@env = env
@loaded = false
end
def id
return @id if @loaded or instance_variable_defined?(:@id)
@id = @store.send(:extract_session_id, @env)
end
def options
@env[ENV_SESSION_OPTIONS_KEY]
end
def each(&block)
load_for_read!
@data.each(&block)
end
def [](key)
load_for_read!
@data[key.to_s]
end
alias :fetch :[]
def has_key?(key)
load_for_read!
@data.has_key?(key.to_s)
end
alias :key? :has_key?
alias :include? :has_key?
def []=(key, value)
load_for_write!
@data[key.to_s] = value
end
alias :store :[]=
def clear
load_for_write!
@data.clear
end
def destroy
clear
@id = @store.send(:destroy_session, @env, id, options)
end
def to_hash
load_for_read!
@data.dup
end
def update(hash)
load_for_write!
@data.update(stringify_keys(hash))
end
alias :merge! :update
def replace(hash)
load_for_write!
@data.replace(stringify_keys(hash))
end
def delete(key)
load_for_write!
@data.delete(key.to_s)
end
def inspect
if loaded?
@data.inspect
else
"#<#{self.class}:0x#{self.object_id.to_s(16)} not yet loaded>"
end
end
def exists?
return @exists if instance_variable_defined?(:@exists)
@data = {}
@exists = @store.send(:session_exists?, @env)
end
def loaded?
@loaded
end
def empty?
load_for_read!
@data.empty?
end
def keys
@data.keys
end
def values
@data.values
end
private
def load_for_read!
load! if !loaded? && exists?
end
def load_for_write!
load! unless loaded?
end
def load!
@id, session = @store.send(:load_session, @env)
@data = stringify_keys(session)
@loaded = true
end
def stringify_keys(other)
hash = {}
other.each do |key, value|
hash[key.to_s] = value
end
hash
end
end
# ID sets up a basic framework for implementing an id based sessioning
# service. Cookies sent to the client for maintaining sessions will only
# contain an id reference. Only #get_session and #set_session are
# required to be overwritten.
#
# All parameters are optional.
# * :key determines the name of the cookie, by default it is
# 'rack.session'
# * :path, :domain, :expire_after, :secure, and :httponly set the related
# cookie options as by Rack::Response#add_cookie
# * :skip will not a set a cookie in the response nor update the session state
# * :defer will not set a cookie in the response but still update the session
# state if it is used with a backend
# * :renew (implementation dependent) will prompt the generation of a new
# session id, and migration of data to be referenced at the new id. If
# :defer is set, it will be overridden and the cookie will be set.
# * :sidbits sets the number of bits in length that a generated session
# id will be.
#
# These options can be set on a per request basis, at the location of
# env['rack.session.options']. Additionally the id of the session can be
# found within the options hash at the key :id. It is highly not
# recommended to change its value.
#
# Is Rack::Utils::Context compatible.
#
# Not included by default; you must require 'rack/session/abstract/id'
# to use.
class ID
DEFAULT_OPTIONS = {
:key => 'rack.session',
:path => '/',
:domain => nil,
:expire_after => nil,
:secure => false,
:httponly => true,
:defer => false,
:renew => false,
:sidbits => 128,
:cookie_only => true,
:secure_random => (::SecureRandom rescue false)
}
attr_reader :key, :default_options
def initialize(app, options={})
@app = app
@default_options = self.class::DEFAULT_OPTIONS.merge(options)
@key = @default_options.delete(:key)
@cookie_only = @default_options.delete(:cookie_only)
initialize_sid
end
def call(env)
context(env)
end
def context(env, app=@app)
prepare_session(env)
status, headers, body = app.call(env)
commit_session(env, status, headers, body)
end
private
def initialize_sid
@sidbits = @default_options[:sidbits]
@sid_secure = @default_options[:secure_random]
@sid_length = @sidbits / 4
end
# Generate a new session id using Ruby #rand. The size of the
# session id is controlled by the :sidbits option.
# Monkey patch this to use custom methods for session id generation.
def generate_sid(secure = @sid_secure)
if secure
secure.hex(@sid_length)
else
"%0#{@sid_length}x" % Kernel.rand(2**@sidbits - 1)
end
rescue NotImplementedError
generate_sid(false)
end
# Sets the lazy session at 'rack.session' and places options and session
# metadata into 'rack.session.options'.
def prepare_session(env)
session_was = env[ENV_SESSION_KEY]
env[ENV_SESSION_KEY] = session_class.new(self, env)
env[ENV_SESSION_OPTIONS_KEY] = @default_options.dup
env[ENV_SESSION_KEY].merge! session_was if session_was
end
# Extracts the session id from provided cookies and passes it and the
# environment to #get_session.
def load_session(env)
sid = current_session_id(env)
sid, session = get_session(env, sid)
[sid, session || {}]
end
# Extract session id from request object.
def extract_session_id(env)
request = Rack::Request.new(env)
sid = request.cookies[@key]
sid ||= request.params[@key] unless @cookie_only
sid
end
# Returns the current session id from the SessionHash.
def current_session_id(env)
env[ENV_SESSION_KEY].id
end
# Check if the session exists or not.
def session_exists?(env)
value = current_session_id(env)
value && !value.empty?
end
# Session should be committed if it was loaded, any of specific options like :renew, :drop
# or :expire_after was given and the security permissions match. Skips if skip is given.
def commit_session?(env, session, options)
if options[:skip]
false
else
has_session = loaded_session?(session) || forced_session_update?(session, options)
has_session && security_matches?(env, options)
end
end
def loaded_session?(session)
!session.is_a?(session_class) || session.loaded?
end
def forced_session_update?(session, options)
force_options?(options) && session && !session.empty?
end
def force_options?(options)
options.values_at(:max_age, :renew, :drop, :defer, :expire_after).any?
end
def security_matches?(env, options)
return true unless options[:secure]
request = Rack::Request.new(env)
request.ssl?
end
# Acquires the session from the environment and the session id from
# the session options and passes them to #set_session. If successful
# and the :defer option is not true, a cookie will be added to the
# response with the session's id.
def commit_session(env, status, headers, body)
session = env[ENV_SESSION_KEY]
options = session.options
if options[:drop] || options[:renew]
session_id = destroy_session(env, session.id || generate_sid, options)
return [status, headers, body] unless session_id
end
return [status, headers, body] unless commit_session?(env, session, options)
session.send(:load!) unless loaded_session?(session)
session_id ||= session.id
session_data = session.to_hash.delete_if { |k,v| v.nil? }
if not data = set_session(env, session_id, session_data, options)
env["rack.errors"].puts("Warning! #{self.class.name} failed to save session. Content dropped.")
elsif options[:defer] and not options[:renew]
env["rack.errors"].puts("Deferring cookie for #{session_id}") if $VERBOSE
else
cookie = Hash.new
cookie[:value] = data
cookie[:expires] = Time.now + options[:expire_after] if options[:expire_after]
cookie[:expires] = Time.now + options[:max_age] if options[:max_age]
set_cookie(env, headers, cookie.merge!(options))
end
[status, headers, body]
end
# Sets the cookie back to the client with session id. We skip the cookie
# setting if the value didn't change (sid is the same) or expires was given.
def set_cookie(env, headers, cookie)
request = Rack::Request.new(env)
if request.cookies[@key] != cookie[:value] || cookie[:expires]
Utils.set_cookie_header!(headers, @key, cookie)
end
end
# Allow subclasses to prepare_session for different Session classes
def session_class
SessionHash
end
# All thread safety and session retrieval procedures should occur here.
# Should return [session_id, session].
# If nil is provided as the session id, generation of a new valid id
# should occur within.
def get_session(env, sid)
raise '#get_session not implemented.'
end
# All thread safety and session storage procedures should occur here.
# Must return the session id if the session was saved successfully, or
# false if the session could not be saved.
def set_session(env, sid, session, options)
raise '#set_session not implemented.'
end
# All thread safety and session destroy procedures should occur here.
# Should return a new session id or nil if options[:drop]
def destroy_session(env, sid, options)
raise '#destroy_session not implemented'
end
end
end
end
end