OnRails.org

Here we go, RailsConf 2007, has started. It’s bigger than ever, more tracks, more sessions. This is the first day where they provide full or half-day tutorials sessions. I will try to cover the different sessions I will attend so stay tuned.

Today I will attend: “Scaling a Rails Application from the Bottom Up.” and “Harnessing Capistrano.”

Scaling a Rails Application from the Bottom Up. by Jason Hoffman

Jason Hoffman, CTO of Joyent. Did also form Textdrive.

Six part presentation:

I. Introduction and foundation II. Where do I put stuff III. What stuff? IV. What do I run on this tuf? V. What are the patterns of deployment? VI. Lessons learned

His presentation will answer the following questions:

• What is a “scalalble” application?
• What are some hardware layout?
• Where do you get the hardware?
• How do you pay for it?
• Where do you put?
• Who runs it?
• How do you watch it?
• What do you need relative to an application?
• What are the commonalities of scalable web architectures?
• What are the unique bottlenecks for Ruby on Rails applications?
• What’s the best way to start so you make sure everything scales?
• what are to common mistakes?

Maybe it’s a little early, or I am not awake, but the talk seems a little slow. But Jason seems to do a good job at describing how the different people (developer, sysadmin, ...) see scalability.

Ease of management is on log scale. It’s not just a Rails issue. A $5000 Dell 1850 costs $1850 to power over 3 year.

This is a really good presentation from a point of view of what is involved to build data center. I should have read better the description of the presentation.

So I am going to move over to Thomas Fuchs presentation:

Is JavaScript Overrated? Or: How I Stopped Worrying and Put Prototype and script.aculo.us to Full Use by Thomas Fuchs

I am just tuning in to his presentation and he is showing of how to use selectors with Prototype.

$('blech').previous('ul').down('.somesuch',2)
$('homo-sapiens').descendantOf('australopothecus')

$('a_div').update('blah').show().setStyle({opacity:0.5});
$('myform').focusFirstElement();
$('person-example').serialize();
Element.addMethods('form') {
  valid: function(element) {
       // code to valid form
  }
}

• speedier $$
• CSS 3 Selectors
• $(‘form’).request()
• String .includes .times .toPaddedString(8,2)
• JSON support i.e. new Date().toJSON();
• $(‘blah’).firstDescendent()
• throw $continue deprecated use “return” instead
• Safari issues fixed
• YAML compatible

DOM, Events, Forms, Position:

• new Element(tagName, attributes);
• $(‘blech’).insert(html|object, position)
• $(‘blech’).wrap(‘span’);
• $(‘country’).setValue(‘AT’);

Function.prototype: curry(), wrap(), defer(), delay() Q: When is the next release of Prototype? A: When it’s ready.

A 10 minute break now, the Thomas is going to present Scriptaculous Effects.

script.aculo.us adds advanced User Interface interaction to the DOM. Extracted from Real-World applications. Started with Fluxiom. The two main parts are Visual effects and Drag&Drop. Today we will only look at the Visual Effects. They are other parts such as Autocompleter, In-Place Editor, Slider control, DOM Builder, and Unit testing. They won’t be more advanced components.

Effects engine: the ideas behind the engine is timeline based animations.

• Effect.Move
• Effect.Opacity
• Effect.Highlight
• Effect.ScrollTo
• Effect.Morph // 1.7+
• Effect.Parallel

Based on the Effect.Base.prototype class. Effect life cycle: intialize(), setup(), update(), finish(). Each frame calls update().

Effect.DefaultOptions = {
    transition: Effect.Transitions.sinoidal,
    duration: 1.0,
    fps: 100,
    sync: false,
    from: 0.0,
    to: 1.0,
    delay: 0.0,
    queue: 'parallel'
}

Morphing: came out with Scriptaculous 1.7.

$('mydiv').morph('font-size:20px; color:"#abcdef");
$('mydiv').morph('warning'); //limited to top level classname

new Effect.Blah('element_2')
new Effect.Blah('element_2', {duration:0.6, delay:0.3});

new Effect.Blah('element_1', {queue:'end'});
new Effect.Blah('element_2', {queue:'front'});

new Effect.Blah('element_1', {queue:{scope:'blech'}});
new Effect.Blah('element_2', {queue:{scope:'blech', position:'end'}});
new Effect.Blah('element_3', {queue:'front'});

Element.toggle('element', 'blind');
Element.tagifyText(element);
Element.multiple('element', Effect.Fade, {speed:0.05});

Do it yourself: Thomas now shows how to create an Effect programatically.

• Sound without Flash (it’s already in the beta release). Sound.paly(‘sword.mp3’). It uses native sound implementation with Quicktime as fallback.
• Adjust to new Prototype features. $(‘blech’).fade(); $(‘blech’).slowlyReveal();

Part IV: Testing

• assert(true)
• assertEqual(expected, actual)
• assertEnumEqual(expected, actual)
• assertNotEqual(expected, actual)
• assertMatch
• assertIdentical
• assertNotIdentical
• assertType
• assertRaise
• assertRespondTo
• assertVisible(element)
• assertNotVisible(element)
• info(message)

Mostly unit testing, but some functional testing is available. Most assert take a message. I.e. assertXYZ(params, message)

• wait(milliseconds, method) // should be last statement in test, but can be nested.
• rake test:javascripts (browser will popup). Done with the javascript_test plugin. Launches the web server (WEBrick), then controls the browsers (Safari, Firefox, IE), the browser then calls the web server, and list the results (SUCCESS, FAILURE, and ERROR)

• www.prototypejs.org
• wiki.script.aculo.us/scriptaculous/
• Book: Prototype and script.aculo.us by Pragmatic Programmer
• Book: Prototype and Scriptaculous in Action by Manning
• Book: Ajax on Rails by O’Reilly

JRuby talk by Charles Nutter and Thomas Enebo

(note taken by Robert Hall, thanks man!)

• 1.8ish—based on Ruby 1.8.5
• Gems 0.9.1 is pre-installed
• Partially compiled—about 80% of Ruby code compiles…rest is run in JIT mode
• Ruby 1.8 strings supported. Works with ActiveSupport::MultiByte
• Ruby 2.0 String support coming
• Most Ruby apps should work on JRuby —most gems just work —Red Cloth, Blue Cloth —Hpricot
• Typical Rails commands just work
• ports: Mongrel ported, Hpricot ported, RMajick in progress
• Ruby thread API supported —native-threaded 1 JRuby thread=1 system thread —supports thread pooling
• performance comparable to C Ruby impl —Rdoc has issues —CLI performance slow
• JDBC support strong —mySQL support strong —some postgres issues —some Oracle users —many others
• ActiveRecord JDBC
• No native extension support
• Goldspike—JRuby deployment tool —Rails plugin for building WAR files —app server agnostic —Can be deployed to Java app server as WAR file
• Deployment—MOngrel supported..some issues (forking, process management doesn’t work)
• Access to Java EE features (JMS, JPA, JTA)
• Java libraries can be wrapped
• Coming soon —A Grizzly/GlassFish V3 option —Lightweight, gem-installable like Mongrel —Concurrency, pooling mulit-app like WAR
• Mephisto demo
• Main idea—- Ruby as the programming language, Java for the platform and libraries
• Best of all worlds —Ruby or Rails as the appl layer —Java libraries alone or as ported/wrapped gems -Java based services-legacy app integration —The JVM
• Acceptable to today’s enterprise —Java to ‘them’, Ruby to you
• Calling Java from Rails demo —RSS reader demo..calling Java library from Rails code
• Tools— Textmate, Emacs, Vi(m), notepad —missing some features —code competion? —jump to declaration? —rename variables? —popup Rdoc?
• Presenters claim Best Ruby IDE Available is NetBeans (milestone 9) —code completion —smart syntax highlightings (for Ruby code, RHTML files, etc) —Rdoc support
• Demoed a cool Ruby shell like IRB implemented in Swing..built into NetBeans
• Jruby 1.0 almost ready

LUNCH: will be back at 1:30pm

Harnessing Capistrano by Jamis Buck

Jamis will focus Capistrano 2.0 today. Some things will not be backward compatible with Capistrano 1.0.

His slides are online at http://presentations.jamisbuck.org/railsconf2007/.