async-http-fiber.rb

# frozen_string_literal: true

require 'net/http'
require 'fiber'
require 'uri'
require 'openssl'
require 'socket'
require 'pp'

require 'benchmark/ips'
require 'benchmark/memory'

require 'memory_profiler'

#rubocop:disable Metrics/LineLength
# :nodoc:
class Selector
  def initialize
    @readable = {}
  end

  def wait_readable(io)
    Fiber.new do
      @readable[io] = Fiber.current
      Fiber.yield
      yield
    end.resume
  end

  def resume
    readable, = IO.select(@readable.keys)
    readable.each do |io|
      fiber = @readable.delete(io)
      fiber.resume
    end
  end

  def run
    resume until @readable.empty?
  end
end

# :nodoc:
class AsyncHTTP
  # :nodoc:
  class Connection
    BODY_SPLIT = "\r\n\r\n".freeze

    attr_reader :hostname, :port, :ssl, :ready, :selector

    def initialize(hostname, port, selector)
      @selector = selector
      @hostname = hostname
      @port = port

      @socket = TCPSocket.new hostname, port
      @ssl = OpenSSL::SSL::SSLSocket.new(@socket)

      @ready = false
      @buffer = +''

      @count = 0
      @requests = 0
      @chunked = false
    end

    def connect
      return if ready
      @ready = true
      ssl.sync_close = true
      ssl.connect
    end

    def start(request)
      @requests += 1
      ssl.write "GET #{request.request_uri} HTTP/1.1\r\nHost: #{request.hostname}\r\n\r\n"
    end

    def wait_response(&block)
      loop do
        break if @count == @requests
        @buffer ||= +''
        @buffer << ssl.read_nonblock(4096)
        if @buffer.include?(BODY_SPLIT) && @chunk == false
          header, @buffer = buf.split(BODY_SPLIT)
          @chunked = true if header.include?('chunked')
        end

        if @chunk == true
          if @buffer.include?("0#{BODY_SPLIT}")
            @chunk = false
            @count += 1
            response, @buffer = @buffer.split("0#{BODY_SPLIT}")
            # TODO: Combine Chunk
            yield response
          end
        else
          @count += 1
          yield @buffer
        end
      end
    rescue IO::WaitReadable
      return if @count == @requests
      selector.wait_readable(ssl) do
        wait_response(&block)
      end
    end

    def close
      return unless ready
      ssl.close
    end
  end

  include Enumerable

  attr_reader :selector

  class << self
    def start(&block)
      new.start(&block)
    end
  end

  def initialize
    @selector = Selector.new
    @pool = {}
  end

  def start(&block)
    instance_exec(self, &block)
    @pool.values.each(&:close)
  end

  def request(request)
    conn = @pool[request.hostname] ||= Connection.new(request.hostname, request.port, selector)
    conn.connect
    conn.start(request)
  end

  def each(&block)
    @pool.values.each do |conn|
      conn.wait_response(&block)
    end
    selector.run
  end
end
#rubocop:enable Metrics/LineLength

uris = [
  'https://api.bitfinex.com/v1/pubticker/BTCUSD',
  'https://api.bitfinex.com/v1/pubticker/ETHUSD',
  'https://api.hitbtc.com/api/2/public/ticker/BTCUSD',
  'https://api.hitbtc.com/api/2/public/ticker/ETHUSD',
  'https://bittrex.com/api/v1.1/public/getmarketsummary?market=USD-BTC',
  'https://bittrex.com/api/v1.1/public/getmarketsummary?market=USD-ETH',
  'https://api.binance.com/api/v1/ticker/24hr?symbol=BTCUSDT',
  'https://api.binance.com/api/v1/ticker/24hr?symbol=ETHUSDT'
]

Benchmark.ips do |x|
  x.report('Fiber') do |c|
    c.times do
      AsyncHTTP.start do |http|
        uris.each do |uri|
          http.request(URI(uri))
        end

        http.each do |body|
          # TODO
        end
      end

      sleep 5
    end
  end

  x.report('Net::HTTP') do |c|
    c.times do
      uris.each do |uri|
        Net::HTTP.get(URI(uri))
      end

      sleep 5
    end
  end

  x.report('[P] Net::HTTP') do |c|
    c.times do
      uris.map do |uri|
        Thread.new { Net::HTTP.get(URI(uri)) }
      end.each(&:join)

      sleep 5
    end
  end

  x.compare!
end

Benchmark.memory do |x|
  x.report('Fiber') do
    AsyncHTTP.start do |http|
      uris.each do |uri|
        http.request(URI(uri))
      end

      http.each do |body|
        # TODO
      end
    end
  end

  sleep 5

  x.report('Net::HTTP') do
    uris.each do |uri|
      Net::HTTP.get(URI(uri))
    end
  end

  sleep 5

  x.report('[P] Net::HTTP') do
    uris.map do |uri|
      Thread.new { Net::HTTP.get(URI(uri)) }
    end.each(&:join)
  end

  x.compare!
end

# MemoryProfiler.report do
#   AsyncHTTP.start do |http|
#     uris.each do |uri|
#       http.request(URI(uri))
#     end
# 
#     http.each do |body|
#       # TODO
#     end
#   end
# end.pretty_print

Warming up --------------------------------------
               Fiber     1.000  i/100ms
           Net::HTTP     1.000  i/100ms
       [P] Net::HTTP     1.000  i/100ms
Calculating -------------------------------------
               Fiber      0.154  (± 0.0%) i/s -      1.000  in   6.505653s
           Net::HTTP      0.119  (± 0.0%) i/s -      1.000  in   8.376975s
       [P] Net::HTTP      0.161  (± 0.0%) i/s -      1.000  in   6.217517s

Comparison:
       [P] Net::HTTP:        0.2 i/s
               Fiber:        0.2 i/s - 1.05x  slower
           Net::HTTP:        0.1 i/s - 1.35x  slower

Calculating -------------------------------------
               Fiber    79.822k memsize (     1.162k retained)
                       279.000  objects (     9.000  retained)
                        45.000  strings (     9.000  retained)
           Net::HTTP     9.085M memsize (    12.521k retained)
                         5.829k objects (   119.000  retained)
                        50.000  strings (    50.000  retained)
       [P] Net::HTTP    17.515M memsize (    10.744k retained)
                         5.851k objects (   105.000  retained)
                        50.000  strings (    50.000  retained)

Comparison:
               Fiber:      79822 allocated
           Net::HTTP:    9084771 allocated - 113.81x more
       [P] Net::HTTP:   17515208 allocated - 219.43x more

Warming up --------------------------------------
               Fiber     1.000  i/100ms
           Net::HTTP     1.000  i/100ms
       [P] Net::HTTP     1.000  i/100ms
Calculating -------------------------------------
               Fiber      0.152  (± 0.0%) i/s -      1.000  in   6.578475s
           Net::HTTP      0.116  (± 0.0%) i/s -      1.000  in   8.648963s
       [P] Net::HTTP      0.162  (± 0.0%) i/s -      1.000  in   6.175362s

Comparison:
       [P] Net::HTTP:        0.2 i/s
               Fiber:        0.2 i/s - 1.07x  slower
           Net::HTTP:        0.1 i/s - 1.40x  slower

Calculating -------------------------------------
               Fiber    83.919k memsize (     1.162k retained)
                       279.000  objects (     9.000  retained)
                        44.000  strings (     9.000  retained)
           Net::HTTP     9.085M memsize (    12.385k retained)
                         5.827k objects (   117.000  retained)
                        50.000  strings (    50.000  retained)
       [P] Net::HTTP    17.466M memsize (    11.139k retained)
                         5.849k objects (   110.000  retained)
                        50.000  strings (    50.000  retained)

Comparison:
               Fiber:      83919 allocated
           Net::HTTP:    9084994 allocated - 108.26x more
       [P] Net::HTTP:   17466200 allocated - 208.13x more

Warming up --------------------------------------
               Fiber     1.000  i/100ms
           Net::HTTP     1.000  i/100ms
       [P] Net::HTTP     1.000  i/100ms
Calculating -------------------------------------
               Fiber      0.153  (± 0.0%) i/s -      1.000  in   6.524378s
           Net::HTTP      0.116  (± 0.0%) i/s -      1.000  in   8.619916s
       [P] Net::HTTP      0.161  (± 0.0%) i/s -      1.000  in   6.193903s

Comparison:
       [P] Net::HTTP:        0.2 i/s
               Fiber:        0.2 i/s - 1.05x  slower
           Net::HTTP:        0.1 i/s - 1.39x  slower

Calculating -------------------------------------
               Fiber    83.919k memsize (     1.162k retained)
                       279.000  objects (     9.000  retained)
                        44.000  strings (     9.000  retained)
           Net::HTTP     9.083M memsize (    11.887k retained)
                         5.803k objects (   116.000  retained)
                        50.000  strings (    50.000  retained)
       [P] Net::HTTP    17.451M memsize (    11.765k retained)
                         5.851k objects (   114.000  retained)
                        50.000  strings (    50.000  retained)

Comparison:
               Fiber:      83919 allocated
           Net::HTTP:    9083352 allocated - 108.24x more
       [P] Net::HTTP:   17450878 allocated - 207.95x more