システム開発を支えるメタプログラミングの技術 / kaigionrails-2022

Kaigi on Rails 2022で発表した「システム開発を支えるメタプログラミングの技術」のスライドです

https://kaigionrails.org/2022/talks/hogucc/

Transcript

1. OGUCHI Haruka @hogucc Oct 21 2022 Kaigi on Rails 2022
2. Haruka Oguchi @hogucc Fintech × SaaS enpay Rails Go
3. 🧙
4. gem
6. 🔮 🔮 🔮 🔮
7. Ruby 2 send, public_send eval, instance_eval, module_eval, class_eval de fi ne_method, de fi ne_singleton_method, method_missing
8. Ruby Ruby include, exclude, prepend Ruby
9. 🔍
10. devise current_xxx devise Rails gem https://github.com/heartcombo/devise current_( ) User ⾒ current_user User Account ⾒ current_account
11. current_user
12. current_user user current_
13. README gem README ⾒ devise current_xxx devise_for current_user routes devise_for
14. include, exclude, prepend de fi ne_method
15. current_user 🔍 module ActionDispatch::Routing class RouteSet prepend Devise::RouteSet end class Mapper def devise_for(*resources) … options = resources.extract_options! … resources.map!(&:to_sym) resources.each do |resource| mapping = Devise.add_mapping(resource, options) … /lib/devise/rails/routes.rb devise_for :users, skip: :all
16. module ActionDispatch::Routing class RouteSet prepend Devise::RouteSet end class Mapper def devise_for(*resources) … resources.each do |resource| mapping = Devise.add_mapping(resource, options) … /lib/devise/rails/routes.rb devise_for :users, skip: :all resources current_user 🔍
17. module ActionDispatch::Routing def self.add_mapping(resource, options) mapping = Devise::Mapping.new(resource, options) … @@helpers.each { |h| h.de fi ne_helpers(mapping) } mapping end … current_user 🔍
18. def self.de fi ne_helpers(mapping) mapping = mapping.name class_eval <<-METHODS, __FILE__, __LINE__ + 1 … def current_#{mapping} @current_#{mapping} ||= warden.authenticate(scope: :#{mapping}) end … METHODS … end lib/devise/controllers/helpers.rb current_user current_user 🔍
19. gem
20. Rails
21. Rails app/ https://zenn.dev/takahashim/articles/ ac 725 fb 16 ec 7 a 11 8 09 c 5
22. GitHub send, public_send eval, instance_eval, module_eval, class_eval de fi ne_method de fi ne_singleton_method method_missing
23. ⾒ clone
26. con fi g settings.yml
27. lib/site_settings/deprecated_settings.rb module SiteSettings::DeprecatedSettings … def setup_deprecated_methods SETTINGS.each do |old_setting, new_setting, override, version| … de fi ne_singleton_method old_setting do |warn: true| If warn Discourse.deprecate( `SiteSetting.#{old_setting}` has been deprecated. Please use `SiteSetting.#{new_setting}` instead. , drop_from: version ) end self.public_send(override ? new_setting : "_#{old_setting}") end … de fi ne_singleton_method
28. module SiteSettings::DeprecatedSettings SETTINGS = [ # [<old setting>, <new_setting>, <override>, <version to drop>] [ search_tokenize_chinese_japanese_korean', 'search_tokenize_chinese', true, 2 . 9 '], ['default_categories_regular', 'default_categories_normal', true, 3 . 0 '], ] def setup_deprecated_methods SETTINGS.each do |old_setting, new_setting, override, version| de fi ne_singleton_method old_setting do |warn: true| … end end … old_setting new_setting lib/site_settings/deprecated_settings.rb
29. module SiteSettings::DeprecatedSettings fi ne_singleton_method old_setting do |warn: true| If warn Discourse.deprecate( `SiteSetting.#{old_setting}` has been deprecated. Please use `SiteSetting.#{new_setting}` instead. , drop_from: version ) end self.public_send(override ? new_setting : "_#{old_setting}") end … Discourse.deprecate Rails.logger.warn lib/site_settings/deprecated_settings.rb
30. module SiteSettings::DeprecatedSettings fi ne_singleton_method old_setting do |warn: true| If warn # end self.public_send(override ? new_setting : "_#{old_setting}") end … public_send String Symbol lib/site_settings/deprecated_settings.rb
31. Redmine HTML macro_xxx xxx HTML macro_issue_link ⾒ public_send xxxPolicy
32. ⾒ de fi ne_singleton_method public_send xxx_counter_increment! xxx
33. Ruby Rails ⾒ Rails