Evaluator - A small Sandbox in Ruby - key => Sandbox

evaluator.rb

require "drb/drb"
require "digest"

class Client
  def get_binding
    return binding
  end
end

class Evaluator
  def initialize
    @clients = {}
  end
  def get
    a = Digest::MD5.hexdigest (Time.now.to_f + rand(1000000)).to_s
    while @clients.keys.include? a
      a = Digest::MD5.hexdigest (Time.now.to_f + rand(1000000)).to_s
    end
    @clients[a] = Client.new.get_binding
    return a
  end
  def evaluate(key, str)
    return nil unless @clients.keys.include? key
    return eval("#{ str }", @clients[key])
  end
end

server = DRb.start_service("druby://localhost:0", Evaluator.new)
puts "Evaluator runs on #{ server.uri }"
server.thread.join()