Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Real-Time HTML5 and Ruby
Search
Luigi Ray-Montanez
March 24, 2012
Programming
3
640
Real-Time HTML5 and Ruby
Presented at RubyNation on March 24, 2012.
Luigi Ray-Montanez
March 24, 2012
Tweet
Share
More Decks by Luigi Ray-Montanez
See All by Luigi Ray-Montanez
A Decade under the Influence
luigi
0
33
Building Upworthy on Rails
luigi
1
90
You'll Never Believe Which Web Framework Powers Upworthy
luigi
0
9.9k
Server-Sent Events at Realtime Conf 2012
luigi
4
440
Developer Happiness & MongoDB
luigi
2
470
Other Decks in Programming
See All in Programming
Tailwind CSSを本気でカスタマイズする方法
fsubal
14
5.5k
Azure OpenAI Serviceのプロンプトエンジニアリング入門
tomokusaba
3
870
if constexpr文はテンプレート世界のラムダ式である
faithandbrave
3
670
Fragment Composition of GraphQL
quramy
13
1.4k
FigmaとPHPで作る1ミリたりとも表示崩れしない最強の帳票印刷ソリューション
ttskch
43
19k
AWS CDKコントリビュートTIPS / aws-cdk-contribution-tips
gotok365
4
370
Java 22 Overview
kishida
1
190
SwiftUIで使いやすいToastの作り方 / How to build a Toast system which is easy to use in SwiftUI
lovee
3
170
雑に思考を整理する技術と効能
konifar
63
30k
敵対的ポイフル
futabato
0
130
OpenAPIを中心に考えるAPI開発入門 / Introduction to API Development with a Focus on OpenAPI
seike460
PRO
2
170
#phpcon_odawara オープン・クローズドなテストフィクスチャを求めて / open closed test fixtures
77web
3
240
Featured
See All Featured
Automating Front-end Workflow
addyosmani
1357
200k
GitHub's CSS Performance
jonrohan
1025
450k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
126
32k
Large-scale JavaScript Application Architecture
addyosmani
504
110k
Web Components: a chance to create the future
zenorocha
306
41k
Happy Clients
brianwarren
92
6.4k
Visualization
eitanlees
137
14k
Thoughts on Productivity
jonyablonski
60
3.9k
The Straight Up "How To Draw Better" Workshop
denniskardys
228
130k
Ruby is Unlike a Banana
tanoku
96
10k
The Pragmatic Product Professional
lauravandoore
26
5.8k
Done Done
chrislema
178
15k
Transcript
Real-Time HTML5 and Ruby Luigi Montanez RubyNation 2012
Overview Part 1 - Real-time HTML5 Technologies Part 2 -
EventMachine Part 3 - Ruby frameworks
tl;dw You can do this stu! in Ruby, you don’t
need Node.js.
Part 1: Real-Time HTML5 Technologies
The Enemy: Page Refreshing
“Classic” Solutions AJAX AJAX Polling COMET (Long Polling)
“Classic” Solutions AJAX AJAX Polling COMET (Long Polling)
WebSockets TCP Socket between browser and server Bi-directional Remains open
until explicitly closed
In the Browser var connection = new WebSocket('ws://example.com/echo'); connection.onopen =
function () { connection.send('Ping'); }; connection.onerror = function (error) { // handle error }; connection.onmessage = function (e) { console.log('Server said: ' + e.data); }; connection.onclose = function () { // ensure you expected a close };
Just TCP A lower level than HTTP Developer de"nes protocol
Support XMPP, IRC, AMQP, VNC Some proxy servers not compatible
No JS Poly!ll Flash-based fallback Socket.IO falls back using di!erent
methods
Bi-directional communication usually overkill.
Server-Sent Events Forgotten little brother of WebSockets Downstream, server to
browser push Just HTTP Browser handles reconnections Pure JS Poly"ll by Remy Sharp
In the Browser var source = new EventSource('/stream'); source.addEventListener('message', function(e)
{ console.log(e.data); }); source.addEventListener('open', function(e) { ... }); source.addEventListener('error', function(e) { ... });
Data data: first line\n data: second line\n\n --- data: {\n
data: "msg": "hello world",\n data: "id": 12345\n data: }\n\n source.addEventListener('message', function(e) { var data = JSON.parse(e.data); console.log(data.id, data.msg); });
Data IDs and Events id: 12345\n data: AAPL\n data: 572.44\n\n
--- data: {"msg": "First message"}\n\n event: userlogon\n data: {"username": "John123"}\n\n event: update\n data: {"username": "John123", "emotion": "happy"}\n\n source.addEventListener('userlogon', function(e) { ... source.addEventListener('update', function(e) { ...
Part 2: EventMachine
Why EM? Many concurrent, long-held connections Addresses the C10K Problem
Can’t use Rails or Rack to support WebSockets and Server-Sent Events
Reactor Pattern Single-threaded event loop listens to many sources Dispatches
synchronous work to handlers Handlers report when done
Timebomb require 'eventmachine' EM.run do EM.add_timer(5) do puts "BOOM" EM.stop_event_loop
end EM.add_periodic_timer(1) do puts "Tick" end end $ ruby timer.rb Tick Tick Tick Tick BOOM
Other Constructs EM#next_tick EM#defer EM::Deferrable EM::Queue EM::Channel
Problem: Pyramid Code or Callback Spaghetti
Tip of the Pyramid EventMachine.run { page = EventMachine::HttpRequest.new('http://example.com/').get page.errback
{ p "Google is down! terminate?" } page.callback { about = EventMachine::HttpRequest.new('http://example2.com').get about.callback { # callback nesting, ad infinitum } about.errback { # error-handling code } } }
EM::Synchrony Ruby 1.9 Fibers Abstracts away callbacks and errbacks Code
looks synchronous but is actually asynchronous
EM + Fiber def http_get(url) f = Fiber.current http =
EM::HttpRequest.new(url).get # resume fiber once http call is done http.callback { f.resume(http) } http.errback { f.resume(http) } return Fiber.yield end EM.run do Fiber.new{ page = http_get('http://www.google.com/') puts "Fetched page: #{page.response_header.status}" if page page = http_get('http://www.google.com/search?q=eventmachine') puts "Fetched page 2: #{page.response_header.status}" end }.resume end
EM::Synchrony::Multi EventMachine.synchrony do multi = EventMachine::Synchrony::Multi.new multi.add :a, EventMachine::HttpRequest.new(uri1).aget multi.add
:b, EventMachine::HttpRequest.new(uri2).apost multi.add :c, EventMachine::HttpRequest.new(uri3).aget res = multi.perform p "Look ma, no callbacks, and parallel HTTP requests!" p res EventMachine.stop end
Part 3: Ruby Frameworks
All built on top of EventMachine
Servers Thin Rainbows!
Cramp Built by Pratik Naik, “lifo” http://cramp.in Supports Fibers $
cramp new myapp
Server-Sent Events class TimeAction < Cramp::Action self.transport = :sse on_start
:send_latest_time periodic_timer :send_latest_time, :every => 2 def send_latest_time data = {'time' => Time.now.to_i}.to_json render data end end
Goliath Built by Ilya Grigorik http://goliath.io Supports EM::Synchrony Both a
server and a framework
Goliath App class Websocket < Goliath::API use Goliath::Rack::Favicon, ‘favicon.ico') map
'/ws', WebsocketEndPoint end
WebSocket Endpoint class WebsocketEndPoint < Goliath::WebSocket def on_open(env) env.logger.info("WS OPEN")
env['subscription'] = env.channel.subscribe { |m| env.stream_send(m) } end def on_message(env, msg) env.logger.info("WS MESSAGE: #{msg}") env.channel << msg end def on_close(env) env.logger.info("WS CLOSED") env.channel.unsubscribe(env['subscription']) end def on_error(env, error) env.logger.error error end end
Frameworks AsyncRack Cramp Faye::WebSocket Goliath
Caveats Separate app Ports vs. Paths Automated Testing
Credits HTML5 Rocks Ilya Grigorik Dan Sinclair Peepcode
Questions?