Current File : //opt/alt/ruby22/lib64/ruby/2.2.0/drb/timeridconv.rb
require 'drb/drb'
require 'monitor'
module DRb
# Timer id conversion keeps objects alive for a certain amount of time after
# their last access. The default time period is 600 seconds and can be
# changed upon initialization.
#
# To use TimerIdConv:
#
# DRb.install_id_conv TimerIdConv.new 60 # one minute
class TimerIdConv < DRbIdConv
class TimerHolder2 # :nodoc:
include MonitorMixin
class InvalidIndexError < RuntimeError; end
def initialize(keeping=600)
super()
@sentinel = Object.new
@gc = {}
@renew = {}
@keeping = keeping
@expires = Time.now + @keeping
end
def add(obj)
synchronize do
rotate
key = obj.__id__
@renew[key] = obj
return key
end
end
def fetch(key, dv=@sentinel)
synchronize do
rotate
obj = peek(key)
if obj == @sentinel
return dv unless dv == @sentinel
raise InvalidIndexError
end
@renew[key] = obj # KeepIt
return obj
end
end
private
def peek(key)
synchronize do
return @renew.fetch(key) { @gc.fetch(key, @sentinel) }
end
end
def rotate
synchronize do
return if @expires > Time.now
@gc = @renew # GCed
@renew = {}
@expires = Time.now + @keeping
end
end
def keeper
Thread.new do
loop do
rotate
sleep(@keeping)
end
end
end
end
# Creates a new TimerIdConv which will hold objects for +keeping+ seconds.
def initialize(keeping=600)
@holder = TimerHolder2.new(keeping)
end
def to_obj(ref) # :nodoc:
return super if ref.nil?
@holder.fetch(ref)
rescue TimerHolder2::InvalidIndexError
raise "invalid reference"
end
def to_id(obj) # :nodoc:
return @holder.add(obj)
end
end
end
# DRb.install_id_conv(TimerIdConv.new)