Rails routing ; concern

concern を使って

resources :user do
  get :search, on: :collection
end

resources :article do
  get :search, on: :collection
end

を

concern :searching do
  get :search, on: :collection
end

resources :user, concerns: :searching
resources :article, concerns: :searching

にできる

         Prefix Verb   URI Pattern                  Controller#Action
   search_users GET    /users/search(.:format)      users#search
          users GET    /users(.:format)             users#index
                POST   /users(.:format)             users#create
       new_user GET    /users/new(.:format)         users#new
      edit_user GET    /users/:id/edit(.:format)    users#edit
           user GET    /users/:id(.:format)         users#show
                PATCH  /users/:id(.:format)         users#update
                PUT    /users/:id(.:format)         users#update
                DELETE /users/:id(.:format)         users#destroy
search_articles GET    /articles/search(.:format)   articles#search
       articles GET    /articles(.:format)          articles#index
                POST   /articles(.:format)          articles#create
    new_article GET    /articles/new(.:format)      articles#new
   edit_article GET    /articles/:id/edit(.:format) articles#edit
        article GET    /articles/:id(.:format)      articles#show
                PATCH  /articles/:id(.:format)      articles#update
                PUT    /articles/:id(.:format)      articles#update
                DELETE /articles/:id(.:format)      articles#destroy