BCR : Ruby on Rails

an introduction

more at http://www.rubyonrails.org/

Background / Agenda

Upcoming web projectFearsWelcome RubyGetting Onto RailsFramework, MVC, Databases, Application Servers and moreDeploying RORWhere to look Next

Considerations

.NETExperienceJ2EEEnterprise AcceptancePHPProven, knowledgebaseRuby on RailsDevelopment Speed, native MVC *and a little fun*

Fears

PHP vs RORStabilityLack of Public Knowledge BaseShark AttackMissing Intelisense

Ruby

Based on SmallTalk, Perl, LispObject OrientedNot strongly typedBasics http://www.fincher.org/tips/Languages/Ruby/FUN? :)

Rails Framework

Power Through Rules and Best PracticeMVCAssumes a DatabaseObject Relational MappingForms Handling Been there done thatParametersLink BuildingScaffolding

MVC

Nothing New, 1973ModelYour Data and Data RulesViewInterfaceControllerTraffic Director

MVC in ROR

View

ShowUser.rhtml

User Name

Controller

Users_controller.rb

def ShowUser

@user = User.find(params[:id])

end

def other

end

def another

end

Model

user.rb

class User < ActiveRecord::Base

#relations

has_many:posts

#start validation here

validates_presence_of :email,

:username, :password

validates_uniqueness_of :email,

:username

End

Model

Object Relational MappingActiveRecordLess Database glue Code *sigh of relief!*Worst Case Scenario Optimizations Possible with manual SQLLogging for Performance Checking

Model : Rules

Table NamesPluralsAttribute Namesid for primary key in tabletable_id for foreign key in other tableAbility to run joins via objects!Article.User.UsernameLegacy Options Available

Model : Sample from Text

Model : Sample from Text

Model : Sample from Text

Model : Code Sample

class User < ActiveRecord::Base

#relations

has_many:posts

#related to rankings

has_many:ranks

has_many:critiques

#start validation here

validates_format_of(:email,

:with => /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i,

:message=>"has an invalid format")

validates_presence_of :email, :username, :password

validates_uniqueness_of :email, :username

#authentication for user

def self.authenticate(username, password)

user = User.find(:first, :conditions => ["username = ?", username])

if user

if user.password != password

user = nil

end

end

user

end

end

Model : DB Logging

Processing SearchController#list (for 127.0.0.1 at 2006-11-18 22:51:36) [POST]

Session ID: 667befe9190e1c686f537e8dcdcd731d

Parameters: {"commit"=>"search", "action"=>"list", "controller"=>"search", "query"=>{"query"=>"test"}}

[4;36;1mArticle Load (0.000000)[0m [0;1mselect a.* from articles a where (lower(a.title) like '%querytest%' or lower(a.articlebody) like '%querytest%' or lower(a.description) like '%querytest%') order by a.created_on desc[0m

Rendering within layouts/search

Rendering search/list

Completed in 0.03100 (32 reqs/sec) | Rendering: 0.01500 (48%) | DB: 0.00000 (0%) | 200 OK [http://localhost/search/list]

Controller

Method name matches view folderusers_controller.rb works for /views/users/***.rhtmlcalled actionsall views methods will sit thereAbility toCRUDFlashRedirect

Controller : ActiveRecord Create

def create

@user = User.new(params[:user])

if @user.save

flash[:notice] = 'User was successfully created.'

redirect_to :action => 'list'

else

render :action => 'new'

end

end

Controller : Flash

def create

@user = User.new(params[:user])

if @user.save

flash[:notice] = 'User was successfully created.'

redirect_to :action => 'list'

else

render :action => 'new'

end

end

Controller : Redirect

def create

@user = User.new(params[:user])

if @user.save

flash[:notice] = 'User was successfully created.'

redirect_to :action => 'list'

else

render :action => 'new'

end

end

Controller : Getting Data

Request Data (POST / GET)Params hashModelsSession dataetc

Views

Show the dataTemplates (layouts)Use objects from controllerNavigate guide into controller / actionForms

Views : Showing Data

Inline Ruby (similar to JSP)

:

'edit', :id => @user %> |

'list' %>

Views : Layouts

Inherit by default for controllerException in controller

#set the layout

layout "articles", :except => [:signin, :richtest]

View : Layout Sample

Admin:

View : Object from Controller

:

'edit', :id => @user %> |

'list' %>

View : Navigation

:

'edit', :id => @user %> |

'list' %>

View : Forms

Native validation based on modelPartials to separate code from main view view _formname.rhtml

Quick Account Signup

'create' %>

'formname' %>

View : Forms

Firstname

Lastname

Email

Username

Password

Scaffolding

FastFamous video (blog in 15 min) http://media.rubyonrails.org/video/rails_take2_with_sound.movDynamic view from DBGreat starting placeNeeds more work

Deploying

Time consuming but straightforwardUnix / Linux hostsTextDriveLightHTTPD serverMySQL

Miscellaneous / Thoughts

Logging Framework Ready to UseInterpreted (no waiting for compile)Once you get the hang of Ruby a lot of fun to quickly developIn the weeds is still in the weeds

Where to Look Next

OReilly Onlamp - Great Starting Placehttp://www.onlamp.com/pub/a/onlamp/2005/01/20/rails.htmlhttp://www.onlamp.com/pub/a/onlamp/2005/03/03/rails.htmlBooks from 37 SignalsAgile Web Development With RailsRails Recipieshttp://www.rubyonrails.org/docs

On the CD

IDE RadRailsBuilt on EclipseDatabase MySQL 5.0 with GUI ToolsEver wonder why the SQL Server 2005 GUI looks like it does? :)OReilly Onlamp ArticlesRuby on Rails Cheat SheetFamous Blog VideoThis Powerpoint Deck