Ruby on Rails Tutorial

Peter Mosca

April, 2007

Ruby on Rails Tutorial

Ruby History

Invented 12 years ago in Japan by Yukihiro Matsumoto

Spent first 5 years in Japan Experienced tremendous growth in

international community since 2000

Ruby on Rails Tutorial

What is Ruby?

Ruby is a dynamically typed OO scripting language similar to Perl and Python

Simple syntax– Principal of Least Surprise (POL)

Advanced language features Scales better than most languages Well-established and robust

Ruby on Rails Tutorial

Ruby on Rails History

Developed by David Heinemeier Hansson in 2004

Extracted from the Basecamp project

Ruby on Rails Tutorial

Ruby on Rails

“Ruby on Rails is a framework that makes it easier to develop, deploy, and maintain web applications”– Dave Thomas, author of The Pragmatic

Programmer

Ruby on Rails Tutorial

Ruby on Rails

Rails is framework, written in Ruby, for developing database-backed web applications

Open Source “Full-Stack” framework

Ruby on Rails Tutorial

Opinionated Software

Trade flexibility at the infrastructure level to gain flexibility at the application level

Designed for the 98% solution, not the 99.9% Push best practices at no extra cost Quick, but not dirty

Ruby on Rails Tutorial

Rails is Opinionated

Convention over Configuration DRY principal Generate boilerplate code

– Get it working quickly, then evolve it Rails makes “best practices” assumptions

– MVC pattern, Unit tests, 3 databases

Ruby on Rails Tutorial

Rails is Opinionated

MVC: Model View Controller pattern– Decouples the domain, presentation, and

workflow 3 Separate Databases

– Development– Test– Production

Ruby on Rails Tutorial

Active Record

“Database Wrapping” instead of “Database Mapping”

Each active record object represents a row in a table

Each record object has CRUD methods for database access

Ruby on Rails Tutorial

Active Record

Adds attributes automatically, based on the columns in the database

Adds relational management through a custom internal language

Naming convention allow database to discover specific fields

Schema migration “baked in” Rails

Ruby on Rails Tutorial

What’s Driving Rails Use?

Rails is fun Rails is powerful Rails development is fast!

Ruby on Rails Tutorial

Rails vs J2EE