Refactoring Rails Applications

Jonathan Weiss, 26.05.2009

Peritor GmbH

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Who am I ?

Jonathan Weiss

•  Consultant for Peritor GmbH in Berlin

•  Specialized in Rails, Scaling, Deployment, and Code Review

•  Webistrano - Rails deployment tool

•  FreeBSD Rubygems and Ruby on Rails maintainer

http://www.peritor.com

http://blog.innerewut.de

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Refactoring

A Definition:

Refactoring is the process of changing internal structure without modifying its external functional behavior or existing functionality with the goals of readability, maintainability, performance, extensibility, and simplicity.

Wikipedia

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From

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To

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(To)

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How?

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Live Coding Experiment

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Principles

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MVC

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Model

Core business model

Domain logic

Reusable

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View

Dumb representation to the outside

Targeted at specific use case

Displays desired information

Different views of one model

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Controller

Conductor & connector

Brokers client requests to backend

Decide & delegate rather then labor

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Principles D R Y

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You Ain’t Gonna Need It

Ron Jeffries:

Always implement things when you actually need them, never when you just foresee that you need them.

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Live Coding Experiment

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Redmine

•  A load-balancer distributes the incoming requests

•  Some load-balancers will deliver static requests themselves

•  Several Rails instances handle all requests

•  Number of concurrent requests equals number of Rails instances

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Redmine

•  Multiple projects support

•  Flexible role based access control

•  Flexible issue tracking system

•  Gantt chart and calendar

•  News, documents & files management

•  Feeds & email notifications

•  Per project wiki

•  Per project forums

•  Time tracking

•  SCM integration (SVN, CVS, Git, Mercurial, Bazaar and Darcs)

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Q & A

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Peritor GmbH

Teutonenstraße 16 14129 Berlin

Telefon: +49 (0)30 69 20 09 84 0 Telefax: +49 (0)30 69 20 09 84 9

Internet: www.peritor.com E-Mail: kontakt@peritor.com

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