Ruby concurrency using the 'concurrent' package.

concurrent.rb

# gem install concurrent-ruby

require 'rubygems'
require 'concurrent'
require 'thread'
require 'open-uri'

module Galaxy
  class Ticker
    def self.get_year_end_closing(symbol, year)
      uri = "http://ichart.finance.yahoo.com/table.csv?s=#{symbol}&a=11&b=01&c=#{year}&d=11&e=31&f=#{year}&g=m"
      data = open(uri) {|f| f.collect{|line| line.strip } }
      data[1].split(',')[4].to_f
    end
  end

  class Hoth
    attr_accessor :document

    def initialize(args={})
      @document = open_document
    end

    def results
      return {
        start: Time.now,
        count_letters: self.count_letters,
        count_unique_letters: self.count_unique_letters,
        count_words: self.count_words,
        finish: Time.now,
        process: Process.pid
      }
    end

    def count_letters
      sleep 2
      @document.length
    end

    def count_unique_letters
      sleep 2
      @document.scan(/\w/).inject(Hash.new(0)){|h, c| h[c] += 1; h}
    end

    def count_words
      sleep 2
      @document.split(' ').count
    end

    def open_document
      sleep 2
      @document = open(default_text_file).read.gsub(/\r/,"").gsub(/\n/, "").strip.chomp
    end

    def default_text_file
      return 'http://textfiles.com/food/boarchil.txt'
    end
  end
end

process = []
symbols = [
  'aapl',
  'goog',
  'fb',
  'c',
  'a',
  'm',
  'bac',
  'intc',
  'siri',
  'ge',
  'msft'
]

# Future (non blocking), will deliver these results, while execution of other code continues
symbols.each { |s| process << Concurrent::Future.execute { Galaxy::Ticker.get_year_end_closing(s, 2013) } }

puts "Enqueued processes to fetch stock prices, they will run behind Galaxy"
puts "Running Galaxy, it is the epitome of blocking code"

# Synchronous blocking code has multiple sleeps, a web request, this will block everything
# except Concurrent::Futures
puts "Start Galaxy: #{Time.now}"
puts "  processes before -> #{process.collect(&:state)}"
Galaxy::Hoth.new.results
puts "Finish Galaxy: #{Time.now}"
puts "  processes after -> #{process.collect(&:state)}"

# Be sure to wait for any remaining processes, they should all be done...
while process.select { |x| x.state == :pending }.any? do end

process.each_with_index do |e,i|
  puts "PROMISE[#{e.state}][#{symbols[i]}] -> #{e.value}"
end
puts "FINISHED: #{Time.now}"