1. Ruby on Rails 探索
kewang

2. Agenda
● What is Ruby?
● What is Rails?
● Live DEMO
● FAQ
● Q&A
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3. What is Ruby?
鑽石恆久遠，一顆就破產
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4. What is Ruby?
●
開放原碼、物件導向的動態直譯式程式語言
●
簡單哲學、高生產力
●
精巧、自然的語法
●
靈感來自 Lisp, Perl, Smalltalk
●
設計的目的是要讓程式設計師 Happy
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5. Matz 說
●
一般程式語言的開發目的
●
可寫出能夠高速運作的程式
●
可在短期間學會寫程式
●
寫一次到處都能跑
●
小朋友也能輕易寫出程式
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6. 但主張「讓寫程式更快樂」的語言卻不太常見
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7. Matz
Ruby is simple in appearance, but is very
complex inside, just like our human body.
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8. Programming Language Type
● Dynamic Strong Language
● Ruby
● Perl
● Python
● PHP is Dynamic, but is not Strong.
● Java is Strong, but is not Dynamic.
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9. EVERYTHING IS OBJECT
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10. irb – Interactive Ruby
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11. TIOBE Ranking
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12. Features
● Iterator
● Code block (closure)
● ! and ?
● Meta-programming
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13. Iterator
●
重複做多次類似的事情
● upto, downto, step, times, collect, map, each_*,
*_each, sort...many methods
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14. Code block (closure)
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15. Code block (closure)
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16. Code block (closure)
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17. Code block (closure)
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18. ! and ?
● ! means side-effect
● ? means return Boolean
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19. ! and ?
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20. Meta-programming
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21. RubyGems
●
Ruby 的套件管理工具
●
所有的 Ruby 套件都可以用 gem 安裝
● Rails
● RMagick
● Heroku
● ...etc.
● http://rubygems.org
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22. Sinatra
● It's a VERY lightweight web development package
● gem install sinatra
● http://www.sinatrarb.com
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23. Hello Sinatra
● ruby myapp.rb, and open http://localhost:4567
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24. Hello Parameter
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25. Sinatra - XDite 如是說
使用 Sinatra 的目的並不是用來開發那些巨型
的 Web application ，而是搭造那些小型的應
用程式或者 API 介面。這樣做有些什麼好處
呢？
如果你只是想寫一支小型程式，或者開發
API ，並不需要使用 Rails 這麼複雜 ( 或肥 )
的 Framework 做這些簡單的事。使用 Sinatra
既簡單， Respond 也迅速。
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26. What is Rails?
火車環島正夯
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27. What is Rails?
● It's a Web Framework
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28. What is Rails?
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29. What is Rails?
● DHH
●
從 37signals 公司的專案
管理工具 Basecamp 裡面
分離出 Ruby on Rails
●
2005 年獲得年度最佳
Hacker
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30. What is Rails?
●
正式名稱 Ruby on Rails
●
使用 MVC(Model-View-Control)
●
內建 unit / integration test
●
支援 Ajax, RESTfFul, ORM
●
支援最新技術 HTML5, jQuery, SASS, HAML, Coffee
Script
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31. Design Principles
DRY
Don't Repeat Yourself
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32. Design Principles
CoC
Convention over Configuration
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33. Rails is so FAST!!!
JSP Rails
4 個月，每週約 20 4 個晚上，每晚 5 小
交貨時間
小時 時
程式碼行數 3293 1164
設定檔行數 1161 113
類別數 / 方法數 62/549 55/126
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34. What is MVC
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35. What is MVC
●
Model 包裝了資料與商業邏輯，例如操作資料庫
●
View 表示使用者介面，顯示及編輯表單
●
Controller 將資料送進送出 Model ，處理從外界
來的 HTTP Request ，與 Model 互動後輸出至
View
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36. DB schema
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37. ActiveRecord (M)
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38. Rails console
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39. Rails console
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40. ActionController (C)
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41. ActionView (V)
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42. What is URL routing?
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43. a bloated controller
class EventController < ApplicationController
index /events/index
show /events/show/1
new /events/new
create /events/create
show_comment /events/3/show_comment/6
mark_spamcomment /events/7/mark_spamcomment/5
add_favorite /events/2/add_favorite
invite /events/1/invite
deny_user /events/1/deny_user/13
allow_user /events/2/allow_user/27
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44. What is RESTful?
before after ActionController
/events/create POST /events events#create
/events/show/1 GET /events/1 events#show
/events/update/1 PUT /events/1 events#update
/events/destroy/1 DELETE /events/1 events#destroy
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45. Let's modify bloated controller
class EventController < ApplicationController
index GET /events events#index
show GET /events/1 events#show
new GET /events/new events#new
create POST /events events#create
show_comment GET /events/3/comments/6 event_comments#show
mark_spamcomment PUT /events/7/comments/5/spam event_comments#spam
add_favorite POST /events/2/favorite events#favorite
invite POST /events/1/invite events#invite
deny_user PUT /events/1/users/13/deny event_users#deny
allow_user PUT /events/2/users/27/allow event_users#allow
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46. RESTful routing
HTTP Verb Path action
GET /photos index
GET /photos/new new
POST /photos create
GET /photos/:id show
GET /photos/:id/edit edit
PUT /photos/:id update
DELETE /photos/:id destroy
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47. One action, multiple formats
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48. One action, multiple formats
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49. Live DEMO
...Never Live DEMO
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50. FAQ
Fxxk you!?
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51. Why Ruby?
● Domain-specific language
● Full object-oriented programming
● High usability
● High readability, maintenance
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52. Why Rails?
● The most successful Web Framework
● Imitation is the greatest compliment
● CakePHP
● Grails
● TurboGears
● catalyst
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53. Websites
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54. Performance Comparison
PHP 5.2.3
Python 2.5.1
Lines of Code
Time per iteration
Language
Ruby 1.9.0 (microseconds)
C++ 4.2.3
Java 1.6
0 100 200 300 400 500 600 700
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愈小愈好

55. Performance is slow?
●
如果一個框架可以讓你僅變快 20% ，或許你應該
繼續使用比較保險的語言，像是 Java 。但是如果
你可以變快 300% 甚至更高，那麼其他的差異都
變的不重要了 from Beyond Java
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56. Q&A
Quick Asleep
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