没有路由匹配错误-带有嵌套资源

routes.rb

  resource :issuer do
    resources :certificates
  end

class Issuer < ActiveRecord::Base
  has_many :certificates
end

class Certificate < ActiveRecord::Base
  belongs_to :issuer
end

No route matches {:action=>\"edit\", :controller=>\"certificates\"}

rake routes

    issuer_certificates GET    /issuer/:issuer_id/certificates(.:format)          {:action=>\"index\", :controller=>\"certificates\"}
                        POST   /issuer/:issuer_id/certificates(.:format)          {:action=>\"create\", :controller=>\"certificates\"}
 new_issuer_certificate GET    /issuer/:issuer_id/certificates/new(.:format)      {:action=>\"new\", :controller=>\"certificates\"}
edit_issuer_certificate GET    /issuer/:issuer_id/certificates/:id/edit(.:format) {:action=>\"edit\", :controller=>\"certificates\"}
     issuer_certificate GET    /issuer/:issuer_id/certificates/:id(.:format)      {:action=>\"show\", :controller=>\"certificates\"}
                        PUT    /issuer/:issuer_id/certificates/:id(.:format)      {:action=>\"update\", :controller=>\"certificates\"}
                        DELETE /issuer/:issuer_id/certificates/:id(.:format)      {:action=>\"destroy\", :controller=>\"certificates\"}