Usando Net::HTTP para consumir httparty.herokuapp.com

client.rb

require 'net/http'
require 'uri'
require 'json'

def get(url, opts)
  opts ||= {}
  uri = URI(url)
  req = Net::HTTP::Get.new(uri.request_uri)
  if opts[:headers]
    opts[:headers].each do |header, value|
      req[header] = value
    end
  end
  Net::HTTP.start(uri.hostname, uri.port){|http|  http.request(req) }
end

def parse_json(res)
  JSON.parse(res.body)
end

host = "http://httparty.herokuapp.com"

#1. Obtener las ids
list_res = get("#{host}/quotes", headers: {'Accept' => "application/json"})

ids = parse_json(list_res).map{|quote| quote["id"] }

#2. Elegir tres al azar

sample = ids.sample(3)
puts "I've chosen: #{sample.inspect}"

cookie = ""

sample.each do |quote_id|
  quote_res = get("#{host}/quotes/#{quote_id}", headers: {'Accept' => "application/json", 'Cookie' => cookie})
  cookie = quote_res['Set-Cookie']
end

#Obtener las leídas
#
puts "Quotes I've read:"

res = get("#{host}/quotes/read", headers: {'Accept' => 'text/plain', 'Cookie' => cookie})

puts res.body