user_access_log.rb

require 'tokyotyrant'

class UserAccessLog
  @@connection = {:master => nil, :slave => nil}
  @@tt_server = {
    :master => {
      :host => "localhost",
      :port => "1978",
    },
    :slave => {
      :host => "localhost",
      :port => "1979",
    }
  }

  attr_accessor :time

  def initialize(user_id, time)
    @user_id = user_id
    @time = time
  end

  def save
    @@connection[:master].put(Digest::SHA1.hexdigest(@user_id.to_s), time.to_s)
  end

  def save!
    raise "Can't save." unless self.save
  end

  class << self
    # setup connection
    def connect
      unless @@connection[:master]
        @@connection[:master] = TokyoTyrant::RDB.new
        unless @@connection[:master].open(@@tt_server[:master][:host], @@tt_server[:master][:port])
          raise "Can't connect ttserver. (#{@@connection[:master].ecode})"
        end
      end

      unless @@connection[:slave]
        @@connection[:slave] = TokyoTyrant::RDB.new
        unless @@connection[:slave].open(@@tt_server[:slave][:host], @@tt_server[:slave][:port])
          raise "Can't connect ttserver. (#{@@connection[:slave].ecode})"
        end
      end
    end

    # find object from TokyoTyrant
    def find(user_id)
      raise "id does not specified." unless user_id

      # connect to ttserver
      connect

      access_time = @@connection[:slave].get(Digest::SHA1.hexdigest(user_id.to_s))
      access_time = nil if access_time.blank?
      self.new(user_id, (access_time ? Time.parse(access_time) : nil))
    end
  end
end