Refactoring towards Component-based Rails Architectures @ RailsConf 2014

You have a big Rails app and are feeling the pains? Stories are hard to deliver, code is hard to refactor, and your tests take a looong time? Getting you and your codebase out of this situation requires you to stop developing a "Rails application” and start refactoring towards your domain. I will discuss how and where you refactor towards a more structured and manageable application, a component-based Rails architecture.

Transcript

1. Big Rails
2. https://github.com/josh-jacobson/Wedloom
3. Refactoring towards Component- based Rails Architectures Stephan Hagemann ! Pivotal Labs Boulder, CO
4. Component-based Rails architectures
5. #cbra
8. github.com/shageman/the_next_big_thing
9. Teaser Email Signup Annoyance Event Counter Rails Container
10. Proxy Partner API Rails Container Registration Internal API
11. Availability and Booking Rails Travel Site Payment Gateway Conversion Tracking
12. Rails TV Shows with Social Network Global Admin Show Admin SMS Interface Social Network Publisher Admin UI Users and Channels
14. WAT?
15. Because it helps
16. How to write #cbra? github.com/shageman/the_next_big_thing ! http://pivotallabs.com/tag/rails-application-suites/ ! confreaks.com/presenters/790-stephan-hagemann confreaks.com/presenters/784-ben-smith ! https://leanpub.com/cbra
17. Big Rails
19. How Big? find . -iname "*.rb" -type f -exec cat {} \; | wc -l
20. How Big? gist.github.com/shageman/11185993
23. Growing size
26. Exploding complexity Size Possible Interactions
27. Versions of Large VS
30. Size Possible Interactions Reduced (Exploding) complexity
32. the rich get richer and the poor get
33. - “Ain't We Got Fun?” - Gus Kahn, Raymond B. Egan the rich get richer and the poor get—children!
34. Preferential Attachment
35. Entities (sorted by size) Size
36. Big Open-Source Rails Apps browsercms! calagator! canvas-lms! citizenry! diaspora opencongress! opengovernment! portlandcrime! railscollab! rubygems.org locomotivecms! fat_free_crm! fulcrum! loc_counts! onebody skyline! snorby! spot-us! spree! teambox tracks
37. What About Code? find . -iname "*.rb" -type f -exec wc -l {} \; | sort -rn
38. What About Code? https://gist.github.com/shageman/11190909
41. user.rb
43. ActiveRecord Associations
44. has_many
45. users model
46. id name home 1 Kate Chicago 2 Pete Boulder 3 Ian Boulder 4 Sam Chicago users table users model
47. id name code 1 red #FF0000 2 green #00FF00 3 blue #0000FF 4 yellow #FFFF00 colors table colors model
48. How many has many? ack " has_many " -c | awk -F ":" '{print $2,$1}' | grep -v "0" | sort -rn
49. How many has many? https://gist.github.com/shageman/11191030
52. user.rb
56. we can do better
61. SOLID
62. Single Responsibility Principle
63. Things that don’t belong
64. SRP - where? Method Class Module Yes! Yes!
65. SRP - where? Method Class Namespace Yes! Yes!
66. Mixins
67. SRP - where? Method Class Namespace Component Application Now you can! Yes! Yes! You should! … Anyone? You should!
68. Components over SOAs 1 repo 1 test suite (and splittable!) 1 deployment no additional versioning constraints easier refactorings between parts
69. Within a SOA componentize your apps
70. Refactoring towards #cbra
72. Teasing out App Component Extracting Functional Component
73. https://leanpub.com/cbra
74. Teasing out App Component
75. Teasing out App Component 0. Got tests?
76. Teasing out App Component 1. Find a vertical that makes sense on its own V C M
77. Teasing out App Component 2. Namespace controllers, views, and models V C M
78. Teasing out App Component 2. Namespace controllers, views, and models V C M
79. Teasing out App Component 3. Hunt down other dependencies V C M
80. Teasing out App Component 4. Move all namespaced code into an engine V C M
81. Teasing out App Component 4b. rails plugin new MY_NEW_COMPONENT --full --mountable V C M
82. Teasing out App Component Step 3. PROFIT! V C M
83. Teasing out App Component PROTIP: Special Case V C M M
84. Extracting Functional Component
85. Extracting Functional Component 0. Got tests?
86. Extracting Functional Component 1. Find functional component
87. Extracting Functional Component 2. bundle gem MY_NEW_COMPONENT
88. Extracting Functional Component 3. move all files into gem (and namespace)
89. Extracting Functional Component 4. move the other stuff the gem needs
90. Extracting Functional Component 5. Require the gem from your app
91. Extracting Functional Component 6. Add shims/ports/adapters to make the app happy
92. Extracting Functional Component Step 3. PROFIT!
94. I will help @shageman
97. Thanks! @shageman