Tuesday, April 29, 2008

Ruby in the browser: a crazy idea whose time has come

This point of this blog post is first, to explain why I think the seemingly nutty idea having ruby execute in the web browser is actually a good one, and second, to show how you can actually do it. Today. It might be a little long, but bear with me.

I've been spending a lot of my free time over the past few months with various different approaches for getting ruby to work inside the web browser. The obvious question would be: Why? Let me start by stating this unequivocally: I do not hate Javascript. I've more than once argued that we as programmers have given not javascript nearly the respect that it deserves. In fact, it was only through treating javascript with respect that I arrived at the conclusions that brought me here.

A few months ago I was working on a project where we needed to move some reasonably complex business logic from the server to the client. The requirements were such that we just couldn't call the logic on the server and have the application behave as desired. I decided to try to use it as an excuse to improve my javascript skills. I used the object oriented features of Prototype, and some visual effects and the unit testing framework of Scriptaculous. To the best of my ability, I tried to approach it my javascript the same way I would any of my "main" development languages. I wrote the code using test driven development and attempted to make it as clearly communicative as possible. And you know what? I actually enjoyed it quite a bit. I was pleased with the code and the users seemed to like the result. I came away with a greatly improved opinion of javascript.

But something I observed bothered me: I ended up creating exactly the same classes in javascript as I had in server side language (in this case Java). This really shouldn't be surprising, since I used test driven design on the server side java code and the client side javascript code it only makes sense it would lead to a similar outcome. But duplicate code has always been (for me) the number one code smell that indicates a need to refactor. As far as I can tell, in order to get rid of this kind of duplicate code I need to develop my core business logic in a language which can execute on both the client (web browser) and the server. I mentioned earlier that I don't think javascript is a bad language, it's not very common for server side development right now and not my first choice. Currently my favorite language for server side code is ruby. If only ruby could execute in the browser. Pure fantasy, right? Believe it or not, there are actually at least 3 possible ways to do it.


First up in my explorations was JRuby. Quite a while back there was an experiment by Dion Almaer to a JRuby applet to execute ruby code in the web page. While this was a nifty experiment when I tried to push this idea further I hit one brick wall after another. The first is that the current JRuby implementation does a lot of things that require additional privileges which means a signed applet. The second which proved more formidable is that javascript code can't call privileged java code at all. This meant that having javascript interact with my ruby code was out. Not good. Though JRuby is near and dear to my heart, this limitation, along with the potential barrier to entry of requiring the Java plugin seemed to make this not a promising solution for what I'm trying to do.


So I gave up on the idea for awhile, until I recently came across HotRuby. HotRuby is a Ruby VM written in javascript. It's a fascinating idea, and it actually works. Under the covers it's really a javascript interpreter for the YARV instruction set. It requires Ruby 1.9 since it depends on YARV. There is a script which dumps out the YARV instructions for a Ruby file in json format. In the browser you include the HotRuby javscript which creates a HotRuby javascript object which executes the jsonified YARV instructions. I installed 1.9 on my machine and checked out the HotRuby code from SVN. In a few hours of playing around, I was able to get it talking with prototype.js and had a simple example where i assigned a ruby block to an onclick event of a button. Although the project seems fairly experimental at this point, it shows great promise. In fact, I was getting ready to blog about it when I came across:


Rubyjs is a ruby compiler that outputs javascript. It requires only Ruby 1.8.6 and installs as a gem which made it easy to get up and running with. Be aware, Ruby 1.8.5 will not work with it, which meant I had to upgrade. Rubyjs leverages another gem, ParseTree, which parses ruby code intos-expressions, which are kind of like a syntax tree. Rubyjs then emits javascript based on these. A bit more complex but seems to work well and can support more of Ruby than HotRuby can so far.

So far Rubyjs seems to be the most viable solution to me. And if you've made it this far into the post, you deserve to be rewarded with some code. To get running is easy, just gem install rubyjs. This will give you a rubyjs command which will take your ruby code and output javascript for it. Rubyjs comes with a few examples but none which really did what I was interested in doing. I wanted to show a simple block of ruby code listening to a button's onclick event. It took a bit of delving into the rubyjs code to figure out how to do it but I think the resulting code came out to be fairly understandable. Here it is:

class DOM
def self.find(element)
`return document.getElementById(#<element>);`

class Button
def initialize(js_element)
@js_element = js_element

def onclick(&block)
element = @js_element
if (#<element>.addEventListener) {
#<element>.addEventListener("click", #<block>, false);
} else {
#<element>.attachEvent("onclick", #<block>);

class Main
def self.main
button = Button.new(DOM.find("button"))
button.onclick { puts "clicked!"}

I create a simple DOM class to help me find an element by id. This shows how you talk to javascript code in rubyjs: by enclosing your javascript code in backticks. Rubyjs does automatically maps javascript objects to ruby and vice versa. I'm not going to delve into the nitty gritty of this too much, I'll do so in a later post.

The more interesting class here is Button. A Button instance gets pass in a DOM element in initialize and instances of button have a single method onclick which receives a block. As you would expect, this allows you to set the onclick handler of a button using a ruby block. The code in the onclick method of Button is also interesting: it shows how you can pass ruby objects into javascript (the javascript code I ripped of from Prototype to do cross browser event observing). Rubyjs will interpolate the javascript code in backticks and replace # type declarations with local variables converting the ruby objects to javascript as appropriate. What this means here is rubyjs is transforming our block into a javascript function for us. Pretty cool, eh?

To see this action, we'll need to compile this ruby code to javascript. The command to do it:

rubyjs button.rb -m Main -d -o button.js

The options tell rubyjs to compile button.rb to button.js. Rubyjs also needs an entry point, which is what -m Main is about. It expects Main to define a class method called Main. Very javaesque, but this is a minor gripe. You can see this code in action here.

There's a lot more to talk about with rubyjs, and I plan this to be the first in a series of posts about it. As part of the project there is also the beginning of a port of GWT to ruby. Altho the code is a bit to javaesque for my tastes so far (as you might expect for a direct port), the idea is very interesting. Let me also issue a giant thank you to Michael Neumann for writing rubyjs and for being incredibly helpful and responsive while I was experimenting. When I asked a question he posted a new version of the gem to address my concern within a few hours. Impressive.


oy said...

WoW shares many wow gold of its features with previously launched games. Essentially, you battle with wow gold cheap monsters and traverse the countryside, by yourself or as a buy cheap wow gold team, find challenging tasks, and go on to higher aoc gold levels as you gain skill and experience. In the course of your journey, you will be gaining new powers that are increased as your skill rating goes up. All the same, in terms of its features and quality, that is a ture stroy for this.WoW is far ahead of all other games of the genre the wow power leveling game undoubtedly is in a league of its own and cheapest wow gold playing it is another experience altogether.

Even though WoW is a Cheap Wow Gold rather complicated game, the controls and interface are done in warhammer gold such a way that you don't feel the complexity. A good feature of the game is that it buy wow items does not put off people with lengthy manuals. The instructions cannot be simpler and the pop up tips can help you start playing the game World Of Warcraft Gold immediately. If on the other hand, you need a detailed manual, the instructions are there for you to access. Buy wow gold in this site,good for you, BUY WOW GOLD.

wow gold said...

Weekends to peopleig2tmean that they can have a two-day wowgold4europe good rest. For example, people gameusdcan go out to enjoy themselves or get meinwowgoldtogether with relatives and friends to talk with each storeingameother or watch interesting video tapes with the speebiewhole family.
Everyone spends agamegoldweekends in his ownmmoflyway. Within two days,some people can relax themselves by listening to music, reading novels,or watchingogeworld films. Others perhaps are more active by playing basketball,wimming ormmorpgvipdancing. Different people have different gamesavorrelaxations.
I often spend weekends withoggsalemy family or my friends. Sometimes my parents take me on a visit to their old friends. Sometimesgamersell I go to the library to study or borrow some books tommovirtexgain much knowledge. I also go to see various exhibition to broadenrpg tradermy vision. An excursion to seashore or mountain resorts is my favorite way of spending weekends. Weekends are always enjoyable for me.
igxe swagvaultoforu wowgold-usaignmax wowgoldlivebrogame thsaleGoldRockU

beautyli said...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I like it

beautyli said...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . good,very good!

beautyli said...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .

This article is very good,I like it !

beautyli said...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . good!good!

Nguyen Manh said...

池袋 風俗
渋谷 風俗
新宿 風俗
av 写真
SM 通販
Hicht hetta hoop
FX ランキング
クレジットカード 比較
ゴールドカード ランキング
浮気調査 探偵
身辺調査 探偵

Nguyen Manh said...

企業調査 探偵
盗聴発見 探偵
特殊調査 探偵
妻の浮気 夫の浮気
妻の浮気 相談
素行調査 相談
身元調査 相談
離婚 相談
追跡調査 相談
ストーカー対策 相談
結婚詐欺 相談
英語 転職

Adi said...

Oes Tsetnoc one of the ways in which we can learn seo besides Mengembalikan Jati Diri Bangsa. By participating in the Oes Tsetnoc or Mengembalikan Jati Diri Bangsa we can improve our seo skills. To find more information about Oest Tsetnoc please visit my Oes Tsetnoc pages. And to find more information about Mengembalikan Jati Diri Bangsa please visit my Mengembalikan Jati Diri Bangsa pages. Thank you So much.
Oes Tsetnoc | Semangat Mengembalikan Jati Diri Bangsa

Edwin said...

Buy Kamagra
Earn Google
Viagra Cialis
Cheap Kamagra
Cheap Viagra
Cheap Cialis
Make Money on Google
M65 Jacket
M65 Field Jacket
Airline Dog Carrier
Airline Dog Carriers
Viagra Cialis
Earn Google
Airline Dog Carrier
Airline Dog Carriers
Airline Approved Dog Carriers
ED Hardy Wholesale
Copy DVD Software
How to Send Fax
14k Yellow Gold
Redneck Costume
14k Gold Heart
Tandem Baby Stroller

carlos said...
This comment has been removed by the author.
carlos said...

Interesting information on "Ruby in the browser: a crazy idea whose time has come" This theme serves to educate people in their daily life, thanks to people like you we have more knowledge about this important issue, and I want to read an article about Negocio Rentable because I need to start a business

icemi said...

wedding dress wedding dress discount wedding dress , Learn French , Learn English , Learn Chinese ,Learn Arabic ,Learn Italian , Learn Korean , Learn Portuguese , dvd boxset .wedding dress ,cheapest wedding dress ,cheapest wedding dresses ! Dell GD761 battery Dell GK479 battery Dell GW240 battery Dell PC764 battery Dell 75UYF battery Dell 8N544 battery Dell NF343 battery , ghd ghd straighteners Dell D5318 battery Dell Y9943 battery Dell RN873 battery Dell G5260 battery 312-0660

aiya said...

Office 2010is powerful!
Microsoft Office 2010is the best software in the world.
Microsoft wordis so great!
Office 2007makes life great!
Many people likeMicrosoft Office.
Microsoft Office 2007is welcomed by the whole world.
Office 2007 keyis available here.
Office 2007 downloadis on sale now!
Office 2007 Professionalbring me so much convenience.
Outlook 2010 make life wonderful!
Microsoft outlook is my love.
Microsoft outlook 2010 is convenient!
Windows 7 is convenient!

Movies Gallery 2011 said...

Nice post. Great blog. Thanks for the share.
Angry Birds Clone| Money Talks|

teramoney said...




xinag zhong said...

I desiredBuy rs goldto show a fairly easy prohibit of ruby code listening to the button's onclick function. The item had taken a certain amount of delving into the rubyjs computer code to figure out the best way to take action on the other hand assume the particular ensuing rule became availableCheapest Diablo 3 gold to get relatively understandable.

AntoL-Nyo said...

HD kaliteli porno izle ve boşal.
Bayan porno izleme sitesi.
Bedava ve ücretsiz porno izle size gelsin.
Liseli kızların ve Türbanlı ateşli hatunların sikiş filmlerini izle.
Siyah karanlık odada porno yapan evli çift.
harika Duvar Kağıtları bunlar
tamamen ithal duvar kağıdı olanlar var

AntoL-Nyo said...

Ben istanbuldan selda 22 yaşında konfeksiyon içşisiyim Amatör Porno sizleri bekletmeden hemen hikayeme geçiyorum.. Biz 5 katlı bir binanın en üst katında yaşıyorduk ve bir öğlen paydosunda sevgilim beni Anal Sikiş aradı evdeydim çünkü evle iş yerim arasında 2 dakika bile yoktu.. Bende Asyalı Porno sevgilime benden telefon beklemesini söyledikten sonra evin durumuna baktım evde kardeşlerim ve annemin Esmer Porno birkaçtane arkadaşı vardı bu iş imkansızdı tekrardan düşündüm ve çatı katı aklıma geldi sevgilime telefon açıp çatıya çıkmasını ve Fantazi Porno beni beklemesini söyledikten sonra telefonu bir süre elime almadım anneme işe gidiyorum dedikten sonra Gay Porno hemen üst kata çatıya çıkıp sevgilimin
dudaklarına yumuldum az bir süremiz Götten Sikiş vardı ve çok istiyordum onu hemen önünde diz çöküp sikini çıkardım kocaman olmuştu bile... Özlemişti beni HD Porno bitanem başladım sikini yalamaya kafasını öpüyor onu çıldırtıyordum sevgilim saçlarımdan tutmuş ağzımı keyifle sikerken çatı katının kapısı açıldı toparlanamadan Lezbiyen Porno komşunun şişman oğlu efecan gelmişti ben dizlerimin üzerinde sevgilimin Liseli Porno siki ağzımda yakalanmıştım hemen bu halimizi gören komşu oğlu Sarışın Sikiş kaçarcasına gitti.. Sevgilim bir süre güldükten Türbanlı Porno sonra bu şişko neden kaçtı korktu herhalde onu sikicem sandı galiba dedikten sonra bir kahkaha daha attı ben sevgilimin Türk Porno sikine deli gibi saldırıyor yalıyor emiyordum boşalmasını istiyor Zenci Porno sütünü içmek istiyordum sevgilim ağzımı sike sike boşaldı hepsini yuttum bir damlasını ziyan Porno etmedim ve sevgilimle vedalaşıp ayrıldık... Ben her defasında sikiş yapmadan önce yazporno diye olan türkçe siteden Porno izle bölümüne girip seyrediyorum azdıktan sonra şahane sikiş ile gözleri kamaştırıyorum.

Alexandra Kate said...

I really liked this part of the article, with a nice and interesting topics have helped a lot of people who do not challenge things people should know, you need more publicize this so many people who know about it are rare for people to know this, Success for you.                                   

Rehane putrie said...

I really liked this part of the article, with a nice and interesting topics have helped a lot of people who do not challenge things people should know... you need more publicize this so many people who know about it are rare for people to know this, Success for you..

Michael Husen said...

AVG 2016 |AVG 2016 | AVG 2016AVG 2016 |AVG 2016 | AVG 2016AVG 2016 |AVG 2016 | AVG 2016AVG 2016 |AVG 2016 | AVG 2016

Google Chrome 2016

Google Chrome 2016

Google Chrome 2016

Google Chrome 2016

Google Chrome 2016

Google Chrome 2016

Google Chrome 2016

Han Choe said...

I love the new site!! I know how much time, thought, and hard work it takes to bring a new site to fruition. You've done it, and beautifully! I'm raising my glass of tea to you in celebration of this enormous achievement!!! Hopefully, one day I'll have the pleasure to clink glasses with you personally!

















Canon PIXMA MX924 Driver Download

Canon MAXIFY MB2000 Driver Download

kmplayer 2016

Canon Pixma mx457 Drivers

Canon ip2770 driver windows 10

El Taufan said...

Thanks for Sharing That... Sucses for You











Kumpul Drivers said...

woow, thanks for sharing friend.
the topic is amazing. i like this!!


cio brokeda said...

thank you for sharing, very useful for the reader , and the site is very prioritizes quality , very nice and best regard


Kumpul Drivers said...

I really liked this part of the article, with a nice and interesting topics have helped a lot of people who do not challenge things people should know.. You need more publicize this so many people who know about it are rare for people to know this... Success for you


Tahir Bahi said...

It’s very straightforward to find out any topic
on web as compared to books, as I found this paragraph at this website.


Candy Sim said...

All the best blogs that is very useful for keeping me share the ideas
of the future as well this is really what I was looking for, and I am
very happy to come here. Thank you very much
earn to die
earn to die 2
earn to die 3
Hi! I’ve been reading your blog for a while now and finally got the
earn to die 4
courage to go ahead and give youu a shout out from
earn to die 6
Austin Texas! Just wanted to tell
earn to die 5
Hi! I’ve been reading your blog for a while now and finally got the
happy wheels
strike force heroes
you keep up the fantastic work!my weblog
age of war
earn to die 5
good game empire
tank trouble
tank trouble 2
strike force heroes