Inside 30days Album - Fighting against legacy Rails #sprk2012

Sapporo RubyKaigi 2012 (札幌Ruby会議2012)

http://sapporo.rubykaigi.org/2012/en/schedule/details/46.html
http://sapporo.rubykaigi.org/2012/ja/schedule/details/46.html

Transcript

1. Inside 30days Album Fighting against legacy code @kyanny #sprk2012 12೥9݄17೔݄༵೔
2. My bitter story For lonely Railers 12೥9݄17೔݄༵೔
3. •Writing tests against legacy code •Technical debt •Attitude towards legacy code 12೥9݄17೔݄༵೔
4. @kyanny Kensuke Nagae ࢗ਎ˑϒʔϝϥϯ 12೥9݄17೔݄༵೔
5. paperboy&co. 12೥9݄17೔݄༵೔
6. http://sqale.jp 12೥9݄17೔݄༵೔
7. http://30d.jp 12೥9݄17೔݄༵೔
8. turn profitable 12೥9݄17೔݄༵೔
9. $ rails -v 12೥9݄17೔݄༵೔
10. 2.0.2 ~ June 2012 12೥9݄17೔݄༵೔
11. ଔ ۀ ੜ 12೥9݄17೔݄༵೔
12. 2.1.2 Jul 2012 ~ 12೥9݄17೔݄༵೔
13. 2008/04 ~ 2012/06 12೥9݄17೔݄༵೔
14. Why need 4 years? 12೥9݄17೔݄༵೔
15. Lack of tests 12೥9݄17೔݄༵೔
16. Need more tests, but... 12೥9݄17೔݄༵೔
17. Writing tests against legacy code is difficult 12೥9݄17೔݄༵೔
18. TDD is idealistic :( 12೥9݄17೔݄༵೔
19. Stub & Mock is your friend :) 12೥9݄17೔݄༵೔
20. Stub def pay! if credit_card.valid? # validate with complex process Payment.create! end end credit_card.stub(:valid?).and_return(true) expects { pay! }.change { Payment.count }.by(1) 12೥9݄17೔݄༵೔
21. Mock def photo.rotate(angle) rpc.call('rotatePhoto', angle) end rpc.should_receive(:call).with('rotatePhoto', 180) photo.rotate(180) 12೥9݄17೔݄༵೔
22. Great weapon for fighting legacy code 12೥9݄17೔݄༵೔
23. 12೥9݄17೔݄༵೔
24. “I was worried about writing tests against existent code. It seems stupid. Is it worth?” 12೥9݄17೔݄༵೔
25. 12೥9݄17೔݄༵೔
26. ࢓༷Խςετ Characterization test http://en.wikipedia.org/wiki/Characterization_test 12೥9݄17೔݄༵೔
27. describe (characterize) the actual behaviour 12೥9݄17೔݄༵೔
28. protect existing behaviour 12೥9݄17೔݄༵೔
29. def sleep_sort(ary) ary.map{|n|Thread.new{sleep n; $*<<n}}.join # What? end def test_sleep_sort ary = [*1..10] sleep_sort(ary) assert_equal ary, $* # need to wait 10+ seconds :P end 12೥9݄17೔݄༵೔
30. “Don't worry. You're right.” 12೥9݄17೔݄༵೔
31. 12೥9݄17೔݄༵೔
32. Technical debt 12೥9݄17೔݄༵೔
33. •Outdated parts •Bad design 12೥9݄17೔݄༵೔
34. BackgrounDRb 12೥9݄17೔݄༵೔
35. “Friends don’t let friends use backgrounDRb.” http://www.engineyard.com/blog/2009/5-tips-for- deploying-background-jobs/ 12೥9݄17೔݄༵೔
36. DelayedJob 12೥9݄17೔݄༵೔
37. DelayedJob Not
38. Monkey patching :P 12೥9݄17೔݄༵೔
39. if Rails::VERSION::STRING <= '2.1.2' unless Time.singleton_methods.include?(:zone) class Time def self.zone Time # enable to call Time.zone.now end end end end 12೥9݄17೔݄༵೔
40. Bad schema 12೥9݄17೔݄༵೔
41. SELECT * FROM photos WHERE album_id = ? AND (deleted_at IS NULL OR deleted_at >= ?) SQL modification by acts_as_paranoid 12೥9݄17೔݄༵೔
42. create_table :photos do |t| t.string :id end Non Integer id (UUID) 12೥9݄17೔݄༵೔
43. Bad schema causes slow queries, but schema change is hard. 12೥9݄17೔݄༵೔
44. Buy high-performance hardware to make up for bad design :) 12೥9݄17೔݄༵೔
45. Long holiday Buy new server & SSD 12೥9݄17೔݄༵೔
46. 12೥9݄17೔݄༵೔
47. Attitude towards legacy code 12೥9݄17೔݄༵೔
48. Be realistic as a business person 12೥9݄17೔݄༵೔
49. Don’t stick the ideal 12೥9݄17೔݄༵೔
50. Be proud as a Developer 12೥9݄17೔݄༵೔
51. Aim for perfect code 12೥9݄17೔݄༵೔
52. 12೥9݄17೔݄༵೔
53. Don't leave a technical debt to future 12೥9݄17೔݄༵೔
54. Break the negative chain 12೥9݄17೔݄༵೔
55. Conclusion 12೥9݄17೔݄༵೔
56. Writing tests against legacy code is difficult. But it will pay. 12೥9݄17೔݄༵೔
57. Technical debt can make up by money. Save your time. 12೥9݄17೔݄༵೔
58. Break the negative chain 12೥9݄17೔݄༵೔
59. Thank you! 12೥9݄17೔݄༵೔
60. Question? 12೥9݄17೔݄༵೔