Question

我曾经设法处理用户注册/登录。我现在正尝试使用CanCan来实现管理员，主持人和普通用户。我希望默认注册为＆＃39;注册＆＃39;或普通用户。我按照指南做了这个。在seeds.rb中：

['admin', 'moderator', 'registered'].each do |role|
    Role.find_or_create_by({name: role})
end

在role.rb中：

class Role < ApplicationRecord
    has_many :users
end

在user.rb中：

class User < ApplicationRecord
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  has_many :todos
  belongs_to :role
  before_create :set_default_role

  private
  def set_default_role
    self.role ||= Role.find_by_name('registered')
  end
end

然而，每当我点击注册时。我在页面上收到错误消息，说“角色必须存在”＆＃39;这就是我在控制台中得到的结果：

Started POST "/users" for 127.0.0.1 at 2018-01-25 10:38:27 +0500
Processing by Devise::RegistrationsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"yBNCK6YInQTx3YsYFSDTToPMpS4NCUz0bTLxGxyeFq2zHWTJWwkkHqcblbsN+7CJEQEsfjtC2VlbuPvVyomv5Q==", "user"=>{"email"=>"umar@gmail.com", "password"=>"[FILTERED]", "password_confirmation"=>"[FILTERED]"}, "commit"=>"Sign up"}
   (0.1ms)  begin transaction
  User Exists (0.1ms)  SELECT  1 AS one FROM "users" WHERE "users"."email" = ? LIMIT ?  [["email", "umar@gmail.com"], ["LIMIT", 1]]
   (0.1ms)  rollback transaction
  Rendering devise/registrations/new.html.erb within layouts/application
  Rendered devise/shared/_links.html.erb (0.6ms)
  Rendered devise/registrations/new.html.erb within layouts/application (2.7ms)
Completed 200 OK in 149ms (Views: 13.6ms | ActiveRecord: 0.3ms)

另外，我还没有触及ability.rb。什么似乎是错的？

Answer 1

而不是在creation阶段设置角色，您应该在验证之前设置它，如下所示：

before_validation :set_default_role, on: [:create, :update]

如果您查看以相同顺序显示所有回调列表的文档，您会注意到在validation回调之前调用create回调。

现在，Activerecord发现用户在role阶段没有附加validation，它会抛出您看到的相同错误。

有关回调的详细信息，请参阅此文档：http://guides.rubyonrails.org/active_record_callbacks.html#creating-an-object

CanCanCan角色必须存在+用户已存在错误

1 个答案: