Reconsider REST: 一种构建大型Rails应用的方式

1. Reconsider REST ⼀一种简洁的组织⼤大型Rails应⽤用的⽅方式 陈⾦金金洲 Founder of Jinshuju, AdMaster michael@jinshuju.net
2. REST
4. Rails Programming Model GET POST PATCH DELETE show create update destroy SELECT INSERT UPDATE DELETE
5. 某知名Ruby论坛 resources :topics do resources :replies end
6. resources :topics do member do post :reply post :favorite delete :unfavorite post :follow delete :unfollow end resources :replies end
7. 某知名Ruby论坛 resources :topics do member do post :reply post :favorite delete :unfavorite post :follow delete :unfollow post :action end collection do get :no_reply get :popular get :excellent get :favorites get :feed, defaults: { format: 'xml' } post :preview end resources :replies end
8. 某知名Ruby论坛 class TopicsController < ApplicationController before_action :authenticate_user!, only: [:new, :edit, :create, :update, :destroy, :favorite, :unfavorite, :follow, :unfollow, :action, :favorites] load_and_authorize_resource only: [:new, :edit, :create, :update, :destroy, :favorite, :unfavorite, :follow, :unfollow, :action] before_action :set_topic, only: [:ban, :edit, :update, :destroy, :follow, :unfollow, :action] def index @suggest_topics = [] if params[:page].to_i <= 1 @suggest_topics = Topic.without_hide_nodes.suggest.fields_for_list.limit(3) end @topics = Topic.last_actived.without_suggest @topics = if current_user @topics.without_nodes(current_user.blocked_node_ids) .without_users(current_user.blocked_user_ids) else @topics.without_hide_nodes end
9. 问题 难于理理解，难于上⼿手 难于测试 复杂产⽣生复杂，产⽣生更更多随意的routing 容易易产⽣生Hacky的代码 容易易产⽣生技术债务
12. class InboxesController < ApplicationControlle def index end def pendings end end
13. class Inboxes def index end def pendings end end class InboxesController < ApplicationControlle def index end end class Inboxes::PendingsController < Applicatio def index end end
14. 这么简单？ 2007 - 2016 It took DHH 10 years.
17. Resource. CRUD. Let’s make ruby-china code better.
18. 某知名Ruby论坛 resources :topics do member do post :reply post :favorite delete :unfavorite post :follow delete :unfollow post :action end collection do get :no_reply get :popular get :excellent get :favorites get :feed, defaults: { format: 'xml' } post :preview end resources :replies
19. r resources :topics do member do post :reply post :favorite delete :unfavorite post :follow delete :unfollow post :action end collection do get :no_reply get :popular get :excellent get :favorites get :feed, defaults: { format: 'xml' } post :preview end resources :replies end resources :favorites resources :followers
20. r resources :topics do member do post :reply post :favorite delete :unfavorite post :follow delete :unfollow post :action end collection do get :no_reply get :popular get :excellent get :favorites get :feed, defaults: { format: 'xml' } post :preview end resources :replies end resources :popular_topics resources :excellent_topics resources :favorite_topics
21. 某知名Ruby论坛 resources :topics do resources :replies resources :favorites, only: [:create, :destroy] resources :followers, only: [:create, :destroy] end resources :no_reply_topics, only: :index resources :popular_topics, only: :index resources :favorite_topics, only: :index
22. 好处 更更容易易理理解 更更容易易测试 ⿎鼓励以资源的⽅方式进⾏行行思考 不不太可能⿎鼓励hack代码 前端开发更更容易易
23. 2012年年
24. 2012年年 「在保持功能正常增长的前提下，项目 功能代码不超过2000⾏。」 ——陈⾦洲，2012
26. resources :forms do member do get :data_collection_status, :print, :reports, :field_attribut get 'qrcode/:size', to: 'forms#qrcode', as: 'qrcode' post :clear_data, :copy end collection do get :participated, :all_names, :associable_data post :preview end resource :theme, controller: 'themes', only: [:update] resources :rules, controller: 'field_rules', only: [:index] do collection do patch :save_field_rules, :save_redirect_rules end end patch :toggle, to: 'form_settings#toggle' resource :setting, controller: 'form_settings', only: [:show, :u
27. 规模之痛 参考《架构腐化之谜》
28. 重构约束 • routes中没有动词 • 最多只使⽤用7个⽅方法：
 new, create, edit, update, destroy, index, show • 让 HTTP Verb + Resource 表达业务 语意
30. resources :forms, except: :index do scope module: 'form' do resources :roles, except: :index resources :cooperators resources :recommended_cooperators, only: [:index] resource :wording, only: [:show, :update] resource :after_submission, only: [:show, :update] resources :webhooks, only: [:index, :update] resources :trackings, only: [:index, :update] resource :publish, only: :show resources :field_rules, :redirect_rules, only: [:index, :crea resource :payment_setting, only: [:show, :update] resources :payment_rules, only: :create resources :open_results, only: [:index, :update] resources :open_searches, only: :update resource :notification_setting, only: :show resource :symbol, only: [:create, :update] resource :theme, only: :update resources :reports, only: :index
31. 能够适应所有场景吗？
32. Case #1: 图⽚片/打印/RSS Feed def show respond_to do |format| format.html.none { render_overview } format.html.print { render_print } format.png { render_qrcode } end end 只是呈现(Representation)问题
33. Case #2: 批量量编辑
34. Case #2: 批量量编辑 resources :entries do collection do post :bulk_delete patch :bulk_update end end resources :batch_updates, only: [:new, :create] resources :batch_deletions, only: [:create] 将「批量量」看做资源
35. Case #3: 审批 POST /membership_requests 201 Created Location /membership_requests/123 GET /membership_requests/123 { status: 'pending' } GET /membership_requests/123 Link: </memberships/100>; rel="membership" { status: 'approved' } 在Header中包含Link信息
36. Case #4: lock/unlock/pin/unpin 使⽤用Resource resource :lock, only: [:create, :destroy] class LocksController < ApplicationController def create @form.lock! end def destroy @form.unlock! end end
37. Case #4: lock/unlock/pin/unpin ⽣生成⼤大量量 Controller 在某些情况并⽆无意义 resources :topics do resources :favorites resources :bans resources :excellences resources :closures end
38. Case #4: lock/unlock/pin/unpin 使⽤用PATCH resources :forms resource :setting, only: [:update] end PATCH /forms/abcdef/setting { status: 'lock' } class SettingsController < ApplicationController def update @form.settings.update_attributes form_settings_params end end
39. Case #5: 移动 对「移动」单独建模，但不不必存储 resources :moves class Move include ActiveModel::Validations attr_accessor :card_id, :from, :to validates :from, :to, presence: true end class MovesController < ApplicationController def create move = Move.new move_params if move.valid? card = Card.find(move.card_id) card.update_attribute column: move.to end
40. 「简单多了」 ——冯智超, chaojiwudi.com
41. REST 定义资源，⽽而不不是动作 正确使⽤用标准HTTP Verb 资源多重呈现（Representation）
42. ⼤大多数Rails Developer 的软件架构能⼒力力都很糟糕 我不不是特指某⼀一两个⼈人
43. #1: 微信公众号开放平台 # 标签管理理 POST https://api.weixin.qq.com/cgi-bin/tags/create GET https://api.weixin.qq.com/cgi-bin/tags/get POST https://api.weixin.qq.com/cgi-bin/tags/update POST https://api.weixin.qq.com/cgi-bin/tags/delete # 获取标签下的粉丝列列表 POST https://api.weixin.qq.com/cgi-bin/user/tag/get # 为⽤用户打标签 POST https://api.weixin.qq.com/cgi-bin/tags/members/batchtagging WTF????
44. #1: 微信公众号开放平台 resources :tags do resources :users end resources :taggings 应该的样⼦子 GET /tags POST /tags GET /tags/1234 DELETE /tags/1234 GET /tags/1234/users POST /taggings { users: [1,2,3,4], tag_id: 1234 }
45. #2: 钉钉开放平台 # 部⻔门管理理 GET https://oapi.dingtalk.com/department/list GET https://oapi.dingtalk.com/department/get?id=2 POST https://oapi.dingtalk.com/department/create POST https://oapi.dingtalk.com/department/update GET https://oapi.dingtalk.com/department/delete # WHAAAAAAT???
46. #2: 钉钉开放平台 # 部⻔门管理理 GET https://oapi.dingtalk.com/department/list GET https://oapi.dingtalk.com/department/get?id=2 POST https://oapi.dingtalk.com/department/create POST https://oapi.dingtalk.com/department/update GET https://oapi.dingtalk.com/department/delete # WHAAAAAAT??? WTF????
47. 架构的意义在于约束 ⽽而不不在于灵活
50. Rails Programming Model GET POST PATCH DELETE show create update destroy SELECT INSERT UPDATE DELETE
51. Thinking about REST GET POST PATCH DELETE show create update destroy SELECT INSERT UPDATE DELETE
52. 总结 思考资源的含义，⽽而不不是动作 思考资源的业务意义，⽽而不不是数据表 routes.rb 中不不出现动词 使⽤用标准HTTP Verb + Resource 组装业务逻辑 每个 Controller 不不超过7个标准⽅方法
53. 谢谢 陈⾦金金洲 jinshuju.com 欢迎加⼊入⾦金金数据