Lecture 10 Rails Projects

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Lecture 10Rails Projects
CSCE 740 Software Engineering

• Topics
• SaaS
• Readings SaaS book Ch 2, 4

February 24, 2014
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SaaS round 2 -

• Finish-up Last Lecture Slides
• Slides ???
• New
• Summary of Rails
• HAML
• Cucumber
• Capybara
• Next Time

• Last Time
• RAILS
• Fig 2.1 100,000 view
• Client-server
• HTTP URIs
• HTML CSS
• HAML

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Rails Summary from Last time

1. The MVC Architecture
2. Components of Rails
3. REST
4. a New Rails Project
5. Rails Application Dir
6. Rails Appl Directory II
7. Directory app
8. HAML - lightweight
9. YAML-human-readable data serialization format

• Configuring a DB
• Creating a DB
• Starting Webrick
• rails generate
• Setting the Application Home Page
• Rails Scaffolding
• Whats Next?
• Rails Summary
• Active Record

CS 169 Saasbook Fox and Patterson
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Chapter 2 SaaS Architecture Review
Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Review Fig 2.3 URI HTTPmethod
Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.4 50,000 ft view
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Fig 2.6 Refining Steps 2 and 3
Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Lamp

• Early SaaS sites were created using the Perl and
  PHP scripting languages, whose
• availability coincided with the early success of
  Linux, an open-source operating system, and
  MySQL, an open-source database.
• Thousands of sites are still powered by the LAMP
  StackLinux, Apache, MySQL, and PHP or Perl.

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Scalability
Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.8 5,000 ft view Refining Middleware
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Architectures for Web Apps

• Left - page controller Sinatra
• Center top front controller J2EE servlets
• Center bottom PHP
• Right MVC used by rails

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.10 5,000 ft view
Saasbook Fox, Armando Patterson, David
(2014-01-31).
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2.6 500 Feet Active Record for Models

• Active Record architectural pattern
• a single instance of a model class (in our case,
  the entry for a single movie) corresponds to a
  single row in a specific table

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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CRUD

• Create a new row in the table (representing a new
  object),
• Read an existing row into a single object
  instance,
• Update an existing row with new attribute values
  from a modified object instance,
• Delete a row (destroying the objects data
  forever).

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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2.7 500 Feet Routes, Controllers, and REST

• REST - In 2000, Roy Fielding proposed, in his
  Ph.D. dissertation, a consistent way to map
  requests to actions that is particularly well
  suited to a service-oriented architecture.
• identify the various entities manipulated by a
  Web app as resources, and
• design the routes so that any HTTP request would
  contain all the information necessary to identify
  both a particular resource and the action to be
  performed on it.
•  In Rails, the route mappings are generated by
  code in the file config/routes.rb,

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.12 Rake Routes Summary

• Operation Method URI action
• Index (list) movies GET /movies index
• Read (show) movie GET /movies/id show
• Display fill-in form GET /movies/new new
• Create from filled-in form POST /movies create
• Display form to edit GET /movies/id/edit edit
• Update movie PUT /movies/id update
• Destroy movie DELETE /movies/id destroy

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.13 Restful vs nonRestful

• Login to site
• Non-RESTful site - POST /login/dave
• URI RESTful site - POST /login/dave
• Welcome page
• Non-RESTful - GET  /welcome
• URI RESTful - GET  /user/301/welcome
• Add item ID 427 to cart
• Non-RESTful - POST /add/427
• URI RESTful - POST /user/301/add/427

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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• View cart
• Non-RESTful - GET / cart
• URI RESTful - GET  /user/301/cart
• Checkout
• Non-RESTful - POST /checkout
• URI RESTful - POST /user/301/checkout

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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ELABORATION REST vs. SOAP vs. WS-

• SOA standards bodies created committees to
  develop standards for SOA interoperation.
• One approach resulted in a collection of
  elaborate protocols for Web Services including
  WS-Discovery, WS-Description, and others,
  sometimes collectively called WS- and jokingly
  called WS-Deathstar by David Heinemeier
  Hansson, the creator of Rails.
• The competing SOAP standard (Simple Object Access
  Protocol) was a bit simpler but still far more
  complex than REST. By and large, practicing
  developers perceived SOAP and WS- as
  overdesigned committee-driven standards burdened
  by the archaic design stance

Saasbook Fox, Armando Patterson, David
(2014-01-31).
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Fig 2.14 500 ft Template views HAML

• Haml HTML
• brclear gt left ltbr clearleft/gt
• p.foo Hello ltp classfoogtHellolt/pgt
• pfoo Hello ltp idfoogtHellolt/pgt
• .foo ltdiv classfoogt. . . lt/divgt
• foo.bar ltdiv idfoo classbargt. . . lt/divgt

Saasbook Fox, Armando Patterson, David
(2014-01-31).