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Why ruby and rails
The document outlines the benefits of using Ruby on Rails for web application development, emphasizing its ability to simplify complex tasks, enhance maintainability, and improve coding speed. It highlights features such as ActiveRecord for database interactions, RESTful resources for standard HTTP operations, and the ease of using reusable libraries (gems). Additionally, it addresses common concerns about Ruby's execution speed, advocating for development and maintainability advantages over raw performance.
Why ruby and rails
- 1. Why Ruby? WhyRails? Reuven M. Lerner reuven@lerner.co.il Hi-Tech College June 27th, 2010
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- 3. Remember Perl? • Strings •Networks • Databases • Very fast coding • (Relatively) fast execution • CPAN!
- 4. Perl had abig problem
- 5. So what? • Unreadablecode = unmaintainable code • Unmaintainable code = eventual disaster
- 7. Web apps arecomplex • HTML • CSS • JavaScript • SQL • Ruby (or another language)
- 8. Web apps arecomplex The really hard part: • HTML Getting these technologies • CSS to work together, smoothly • JavaScript • SQL • Ruby (or another language)
- 9. Rails to therescue! • Smooths the edges between these parts • Reduces the pain in writing apps • Encourages you to write maintainable code • Allows you to focus on your domain
- 10. It’s all aboutthe data • Philip Greenspun • The data model is key • Provided a model (ACS) • Rails says: Create one!
- 11. ActiveRecord • Makes iteasy to work with databases • Zero lines of code, for starters! • Lets you write a DSL (domain-specific language) that describes your data • Validations, callbacks, scopes
- 12. Other data stores •MongoDB • Memcached • Redis • Cassandra • Amazon S3 • You name it...
- 13. RESTful resources • StandardHTTP interface to actions • GET, POST, PUT, DELETE the way they were supposed to be used • Built into Rails, works automatically • Gives you lots automatically
- 14. Separation • MVC +H • Models, views, controllers + helpers • Push code to the model • Conventions — but they work • Read someone else’s code without crying • Read your own code without crying!
- 15. Environments • development, testing,production • Create your own (e.g., “staging”) • Each can load different libraries • Each has its own log levels
- 16. Console >> p =Person.find(1) => #<Person id: 1, email_address: "reuven@lerner.co.il", first_name: "reuven", last_name: "lerner", password: "foo", administrator: true, created_at: "2009-07-08 12:50:42", updated_at: "2010-06-10 10:51:04", avatar_file_name: "Reuven_headshot.jpg", avatar_content_type: "image/ jpeg", avatar_file_size: 1248486, avatar_updated_at: "2010-06-06 19:22:00"> >> p.update_attributes(:administrator => true) => true >> p.nodes.length => 6
- 17. Filters • Execute codebefore or after any controller actions before_filter :require_login, :only => [:edit, :update, :logout, :tags] • Authentication • Common variable settings • Logging
- 18. Rake • Sort oflike “make” — but in Ruby • Tasks have access to objects • Automate all sorts of tasks • Migrating data • Creating sitemaps
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- 20. Software ICs • Reusablecode libraries • Multiple libraries that adhere to a spec • Download and install • First suggested in 1986! • Cox put these ideas into practice • Ever hear of Objective-C?
- 21. Gems • Reusable librariesof Ruby code • As little as a constant • As big as a complete CMS • Download, install, and use! • Open source — free to use and change
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- 24. Some gems • Paperclip(attachments) • Devise (authentication) • MongoMapper (MongoDB access) • will_paginate (pagination)
- 25. Plugins • Want orneed to change Rails itself? • Write a plugin! • Or use one of the many out there • (some of which now come as gems)
- 26. Some plugins • acts_as_tree(hierarchical models) • html_test (check validity of views) • annotate_models (add column lists)
- 27. My brain istoo small! • Yes, there’s a lot to learn • Most of it can wait a little bit • Start with what you know • Improve yourself and your code over time
- 28. Wait, isn’t Rubyslow? • Yes. For now. • JRuby, Gemstone, Ruby 1.9/2.0 • Is execution speed your biggest worry? • Development speed • Reliability • Maintainability
- 29. So, why Rails? •Common Web development tasks are easy • You write less code • The code that you do write is better • You can maintain your code more easily • Less pain dealing with many Web issues
- 30. Finally, because it’sfun “I tried to make people enjoy programming and concentrate on the fun and creative part of programming when they use Ruby.” — Matz
- 31. Join us! • Israel.rb(Google group) • Ruby, Rails courses right here! • Call me: 054-496-8405 • E-mail me: reuven@lerner.co.il • Interrupt me: reuvenlerner (Skype/AIM)