This document summarizes the key points in migrating a legacy Rails 2.0 application to a newer version of Rails. It discusses upgrading to Rails 2.3 first to address compatibility issues. Then it recommends upgrading to Ruby 2.1 and Rails 4.1 to get performance improvements from the language and framework updates. Various techniques are presented for the migration process such as running the newer versions in production gradually.

1. !
From ‘Legacy' to ‘Edge'
2014 edition
!
Hiroshi SHIBATA
@hsbt
OedoRubyKaigi04

2. SHIBATA Hiroshi(@hsbt)

3. asakusa.rb

4. ruby-lang.org

5. Rails Girls in Japan

6. Ruby Committer

8. ミドルウェアのアップグレード
アクセス解析基盤の構築
セキュリティ監査
Ruby/Rails
技術リ基ーンス盤タートチアップ
ーム
社内開発基盤の構築
JSOXの運用整備
統計基盤の構築
github
テスト基盤の構築コードレビュー
新人教育
開発プロセス
原稿執筆
カンファレンス発表
Jenkins
RDBMS
OSS開発サーバー構成管理の刷新

9. http://30d.jp

10. from 2007/5

11. 380,000 users
230,000,000 photos

12. Our Rails app
46 models
5000 lines in controllers
400 lines in routes.rb
1:1.3 code to test ratio

13. system architecture

14. application server

15. storage server

16. job server

17. transaction server

18. storage is over
450 TB

19. database size
is over
250 GB

20. Development
Culture

21. 文字github workflow

22. IRC
github issue
costomer’s
contact
nagios

23. DevOps

24. 4 deploy/day

26. How to migrate
edge rails
from
legacy rails?

27. Ruby 1.8.6
Rails 2.0.2

28. Ruby 1.8.6
Rails 2.0.2
Ruby 2.1.1
Rails 4.1.0 new!

29. Why?

31. Ruby on Rails

32. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

33. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
Slow
4.0 Fast

34. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

35. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

36. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

37. Rails 2.0
Rails 2.3

38. Rails 2.0
hotfix A
Rails 2.3
migration A

39. Rails 2.0
hotfix A
Rails 2.3
migration A

40. Rails 2.0
hotfix A
Rails 2.3
migration A

41. 文字

42. Zero
Downtime
Deploy

43. cookpad/kage

44. Kage (kah-geh) is an HTTP shadow
proxy server that sits between
clients and your server(s) to
enable "shadow requests".

45. the basic of kage
real request

47. _人人 人人__人人 人人_!
> 突然のサーバー再起動 <!
‾Y^Y^Y^YY^Y^Y^YY^Y

48. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

49. rails 2.3 with bundler

50. source 'https://rubygems.org'!
!
gem 'rails', '~> 2.3.18'!
gem 'rake', '~> 0.9.2'!
gem 'rdoc'!
gem 'rake-confirm'!
!
gem 'mysql'!
gem "mysql_retry_lost_connection"!
gem 'acts_as_paranoid', :github => 'paperboy-30days/acts_as_paranoid'!
gem 'passenger', '~> 3.0'!
gem 'memcache-client', :require => 'memcache'!
gem 'system_timer'!
gem 'yajl-ruby', :require => 'yajl'!
gem 'will_paginate', '~> 2.3'!
gem 'mail'!
!
gem 'sass'!
gem 'compass-rails'!
!
gem 'osaipo_client', :git => 'git@github.com:paperboy-all/
osaipo_client.git', :branch => 'legacy'!
gem 'jugem_client', :git => 'git@github.com:paperboy-all/
jugem_client.git'!
gem 'ppb_footer', :github => 'paperboy-all/ppb_footer'!

51. require "./config/environment"!
!
use Rails::Rack::LogTailer!
use Rails::Rack::Static!
run ActionController::Dispatcher.new
rack with rails 2.3

52. can’t use
hyphen
30days-front
can’t use
number
can’t convert
! application.rb...

53. Reduce
customer frustration.

54. app1
app2
backgroundrb to dj

55. 文字

56. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

57. Use trunk everyday.

58. 文字

59. 文字

60. Use modern architecture

61. app1
app2

62. kyoto tycoon is slower
than mysql…

64. 1.8 to 2.0

65. 文字

66. 2.0 to 2.1

67. CPU Usage(%)
100
75
50
25
0
49
2.0 2.1
69

68. Resp. time(ms)
250
200
150
100
50
0
189
2.0 2.1
221

69. 4
3
memory usage(giga byte) 0
2
1
3.8
2.0 2.1
3.2

70. 文字https://www.ruby-lang.org/en/news/2014/03/10/regression-of-hash-reject-in-ruby-2-1-1/

71. Ruby
1.8.6 1.8.7 1.9.3 2.0.0 2.1
Rails
2.0/2.1
2.3
3.0
3.2
4.0

72. 文字

73. Resp. time(ms)
300
240
180
120
60
0
287
3.2 4.0
189

74. Ruby
1.9.3 2.0.0 2.1 2.2
Rails
3.0
3.2 ?
4.0 ?
4.1 ?

75. Ruby
1.9.3 2.0.0 2.1 2.2
Rails
3.0
3.2 ?
4.0 ?
New!!
4.1 ?

76. 文字

77. 1. Flash structure changes
2. Mutator methods called on Relation

78. 文字

79. Resp. time(ms)
300
240
180
120
60
0
266
4.0 4.1
287

80. Ruby
1.9.3 2.0.0 2.1 2.2
Rails
3.0
3.2 ?
4.0 ?
4.1 ?

81. class Bar!
def bar(foo = foo())!
foo!
end!
!
def buzz(foo = foo)!
foo!
end!
!
def foo!
:buzz!
end!
end!
!
p Bar.new.bar!
p Bar.new.buzz

82. % ruby -v r45272.rb!
ruby 2.2.0dev (2014-04-13 trunk 45580) [x86_64-darwin13]!
:buzz!
nil!
!
% ruby -v r45272.rb!
ruby 2.1.2p80 (2014-03-01 revision 45231) [x86_64-darwin13.0]!
:buzz!
:buzz

83. 文字

84. conclusion

85. 1. fix your code
2. fix gem
3. fix Rails
4. fix Ruby