Ruby on Your Rails

Slides for RubyKaigi 2013 talk "Ruby on Your Rails" http://rubykaigi.org/2013/talk/S84

Transcript

1. Ruby on Your Rails Akira Matsuda @ RubyKaigi 2013
2. "go west"
3. Japan.map ,ZPUP .BU[F 5PLZP
4. Tokyo.map "LJIBCBSB (JO[B
5. Tokyo.map "TBLVTB
7. The next Asakusa.rb meetup (drinkup) http://asakusarb.doorkeeper.jp/ events/4149
8. whoami Twitter: @a_matsuda GitHub: amatsuda
9. Announcement! GitHub Drinkup this evening!! https://github.com/blog/1515- tokyo-drinkup
10. amatsuda Ruby on Rails Ruby Haml Kaminari ...
11. How to "go west" on Rails
12. How can we write WHERE + NOT, WHERE + LIKE queries?
13. User.where(name: 'Matz') #=> SELECT * FROM users WHERE name = 'Matz' User.where('name != ?', 'Matz') #=> SELECT * FROM users WHERE name != 'Matz' SELECT * FROM users WHERE name != 'Matz'
14. SELECT * FROM users WHERE name != 'Matz' We should be able to do this with Hashes We were apparently missing this feature But it wasn't implemented because a good feature needs Proper use case Good API Good implementation
15. WHERE name != 'Matz' was not in AR3 not because it was not possible to implement In fact, it could be done using Arel Objects
16. where(Arel node) User.where( User.arel_table[:name].not_eq('Matz') ) #=> "SELECT `users`.* FROM `users` WHERE (`users`.`first_name` != 'Matz')"
17. WHERE name != 'Matz' was not in AR3 because We just couldn't nd a good API Syntax matters (ʮ໊લॏཁʯ)
18. Re nements... # where + block User.where { :name != 'Matz' }
19. amatsuda/everywhere A Rails plugin that enables `WHERE + NOT`, `WHERE + LIKE` and `WHERE + NOT LIKE` queries Users can switch syntax via con guration
20. everywhere # :not in Hash value User.where(name: {not: 'Matz'}) # :not in Hash key User.where(not: {name: 'Matz'}) # :not + Hash User.where(:not, name: 'foo') # special method User.where_not(name: 'foo')
21. @tenderlove & @jonleighton I don't like the idea of adding "special" hash keys me neither in fact, since I added hstore support, that technique won't work on PG
22. @bitsweat Perhaps a Model.where with no args should be chainable: Model.where.not eld: nil or Model.where.like name: 'John%'
23. Committed where.not where.like where.not_like
24. @dhh says Akira Matsuda, where.not is a beaut ul DSL solution. Props! Love when a hard problem like that turns out to have a simple DSL solution we just didn't see.
25. @dhh says imo, I think already like/not_like are going too far like/not_like are very rare cases and they just open the door to the monstrocities of gte they're also weird because you need % so it's this bastard version of half sql in the statement, half sql in the parameter Any counter arguments?
26. Then partially reverted where.not where.like where.not_like
27. Lessons learned Publish your idea as a gem so that others can investigate and give a try Jeremy is awesome. He is always right DHH is awesomer (͓͏͞·ʔ) #ବᔬམΫϥϒ AR4 now has where.not feature
28. Why our controller actions don't look like Ruby code?
29. "Merbish" controllers
30. Why aren't our actions like this? class UsersController < ApplicationController def show(id) @user = User.find(id) end end
31. "params" class UsersController < ApplicationController def show @user = User.find(params[:id]) end end
32. How our controllers work $params = {greeting: 'Hello, world!'} def foo puts $params[:greeting] end foo
33. asakusarb/action_args
34. More examples class UsersController < ApplicationController def show(id) @user = User.find(id) end def create(user) @user = User.new(user) if @user.save ... end end def update(id, user) @user = User.find(id) if @user.update_attributes(user) ... end end end end
35. @dhh says I was initially excited about it Problems with the action_args approach is that it doesn't deal with the preload pattern very gracefully You're passing in a parameter that just says "user", but it's not a user object, like the one assigned to @user, it's a set of parameters for the user. params[:user] is much more clear about what this variable actually contains
36. @dhh's conclusion I don't think it's going to work as a good t for core
37. Helpers are ugly, and my models are too fat
38. Use decorators
39. amatsuda/ active_decorator
40. I heard that our browsers can also do some form validations. Why not on my Rails app?
41. let your validations DRY
42. amatsuda/ html5_validators
43. Sexy validations? Seriously? Are they?
44. Good ol' validations class Person # validations start from here validates_presence_of :name, :age validates_length_of :name, maximum: 255 validates_numericality_of :age, greater_than: 0 # validations end ... end
45. "sexy validations" validates :name, presence: true
46. IMO It would be sexier if DRYer grouped no "{something: true} thing
47. validates + block - def validates(*attributes) + def validates(*attributes, &block)
48. validates + block class Person validates do presence_of :name, :age length_of :name, maximum: 255 numericality_of :age, greater_than: 0 end ... end
49. validates + block class Person validates :name do presence length maximum: 255 end validates :age do presence numericality greater_than: 0 end ... end
50. I can bake it into a gem, probably?
51. Conclusion Stay on the Edge Be careful and critical Try to solve YOUR problems Send your PRs!