mileszs

I am a lot quieter on the Internet

PPL30 Day 28: DRb

Today… err, yesterday, I began looking at Distributed Ruby, or DRb. DRb is a system for allowing Ruby processes to communicate with each other. Really, it’s a client/server thing.

This is part of the Peer Pressure Learning 30 series. To learn more about what in the hell that means, see the intro to the series, A Good Time To Learn.

Installation

NOTHING! DRb is included in Ruby 1.8+.

todo list nothing

Resources

The DRb Site

I started with what I believe to be the DRb site. In particular, the Introduction to DRb was a pretty straightforward way to get started. If your eyes are up to the task of actually reading the content on this site, the content can be quite informative.

bloodshot eye

What I Think I Now Know

DRb is a lot of fun to play with, for some reason. I don’t really think the DRb site quite does it justice, actually. There are many possibilities. For instance, distributed FizzBuzz!

Server:

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#!/usr/bin/env ruby
#
# Server

require 'drb'

class FizzBuzz
  def initialize(range = 1..100)
    @range = range
  end

  def range=(home)
    @range = home
  end

  def fizzbuzz
    @range.to_a.map do |num|
      result = ''
      result = 'Fizz' if num % 3 == 0
      result += 'Buzz' if num % 5 == 0
      result.empty? ? num : result
    end
  end
end

DRb.start_service 'druby://:9000', FizzBuzz.new
puts DRb.uri

trap("INT") { DRb.stop_service }
DRb.thread.join

Client:

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#!/usr/bin/env ruby
#
# Client

require 'drb'

DRb.start_service
fb = DRbObject.new nil, 'druby://:9000'
fb.range = 1..200
fb.fizzbuzz.each {|r| puts r }

Of course we need to access FizzBuzz answers from a remote client, right? Place each of those in an executable file (e.g. the server script in server.rb, the client script in client.rb). Then, in one terminal window, run ./server.rb, and in the other run ./client.rb. MAGIC!

magic johnson

I really recommend giving the Introduction to DRb a quick skim, at least. It’s really not too complicated, as long as you’re awake enough to read it clearly.


I’m so close. I will be doubling up tomorrow, as tomorrow marks the final day of the PPL30. I swear, I’m going to finish. Success is within my grasp, and I shall not allow accolades of such great import slip feebly from my fingers! … Yup, so, Schema and MacRuby.