ruby-on-rails - Rails 不使用模型指定的表

Question

我有一个子类化另一个模型的模型，这个特定模型不使用我指定的表，而是默认返回到试图找到该表的父类。

父类在gem中，子类在 namespace 隔离的引擎中。

父级(在 gem 中):

require_relative 'concerns/user_concerns'
require 'bcrypt'

module CoreModels
  module Models
    class User < ActiveRecord::Base
      self.abstract_class = true

      extend FriendlyId
      friendly_id :first_name, use: [:slugged, :finders, :history]

      before_save :encrypt_password

      has_many :group_memberships, :dependent => :delete_all
      has_many :groups, :through => :group_memberships, :dependent => :delete_all
      has_many :roles, :through => :group_memberships, :dependent => :delete_all

      has_many :api_keys

      validates :first_name, presence: true
      validates :user_name, uniqueness: true, presence: true, length: {minimum: 5}
      validates :email, presence: true, confirmation: true, uniqueness: true
      validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i
      validates :password, presence: true, confirmation: true, length: { minimum: 10 }, if: :new_record?

      include CoreModels::Models::Concerns::UserConcerns

      before_create{ generate_token(:auth_token) }

      def self.authenticate_user(user_name, password)
        user = Xaaron::User.find_by_user_name(user_name)
        if(user && (user.password == BCrypt::Engine.hash_secret(password, user.salt)))
          user
        else
          nil
        end
      end

      def encrypt_password
        if password.present?
          self.salt = BCrypt::Engine.generate_salt
          self.password = BCrypt::Engine.hash_secret(password, salt)
        end
      end

      def send_password_reset
        generate_token(:password_reset_token)
        self.password_reset_timestamp = Time.zone.now
        save!
        UserMailer.password_reset(self).deliver
      end

      protected
      def generate_token(column)
        begin
          self[column] = SecureRandom.urlsafe_base64
        end while User.exists?(column => self[column])
      end
    end
  end
end

child (在引擎中):

require 'core_models/models/user'

module Xaaron
  class User < CoreModels::Models::User
    self.table_name = 'xaaron_users'
  end
end

当我运行我的测试时，其中 135 个失败，一遍又一遍地给我同样的错误:

Failure/Error: setup_group_role_permissions_relations_for_administrator
     ActiveRecord::StatementInvalid:
       PG::UndefinedTable: ERROR:  relation "users" does not exist
       LINE 5:                WHERE a.attrelid = '"users"'::regclass
                                                 ^
       :               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                            pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
                       FROM pg_attribute a LEFT JOIN pg_attrdef d
                         ON a.attrelid = d.adrelid AND a.attnum = d.adnum
                      WHERE a.attrelid = '"users"'::regclass
                        AND a.attnum > 0 AND NOT a.attisdropped
                      ORDER BY a.attnum

这个特殊的方法是:

def setup_group_role_permissions_relations_for_administrator
  @user = FactoryGirl.create(:user)
  @role = FactoryGirl.create(:admin_role)
  @group = FactoryGirl.create(:administrator_group)
  @permission = FactoryGirl.create(:can_read)

  @role.add_permission = @permission.permission_name
  @group.add_role = @role.role_name

  @user.add_group_membership(@group, @role)
end

所以你可以看到当我说使用表 x 时它没有听我说。相反，它试图使用一个不存在的表。/我所有的引擎表都是用 xaaron_

命名空间的

更新

经过一些调查，核心问题是 FactoryGirl，如果我们看一下发生在以下位置的第一件事:setup_group_role_permissions_relations_for_administrator 我在做 @user = FactoryGirl.create(:user)，当我用 pry 弄清楚那里发生了什么时 - 这就是问题所在，所以让我们看看这个工厂:

FactoryGirl.define do
  sequence :user_email do |n|
    "user#{n}@example.com"
  end

  # Allows for multiple user names
  sequence :user_name do |n|
    "user#{n}"
  end

  sequence :permission_name do |n|
    "can_read#{n}"
  end

  sequence :role_name do |n|
    "Member#{n}"
  end


  factory :user, :class => Xaaron::User do
    first_name 'Adam'
    last_name 'Something'
    user_name {generate :user_name}
    email {generate :user_email}
    password 'somePasswordThat_Is$ecure10!'
  end

  factory :admin, :class => Xaaron::User do
    first_name "Sample Admin"
    email "a@gmail.com"
    user_name "Admin_User_Name"
    password "admin_Password10985"
  end
end

factory girl 创建用户的方式有问题，因为我可以启动 Rails 控制台并执行 Xaaron::User.all 并且它知道查看 xaaron_users 而不是 users

所以 self.table_name="" 可以工作，但由于某种原因不能与工厂女郎一起工作。

更新2

我已经在以下位置提交了一份可能的错误报告:Their Github Repo

Answer 1

一般来说，Active Record 被设计为使用单表继承(同一张表用于所有子类的记录)而不是多表继承(子类使用不同的表。)

也就是说，您可以尝试覆盖 table_name 方法，而不是使用 self.table_name = 在您的子类中设置表名

def table_name
  'xaaron_users'
end

看看这是否适用于您的场景。这是 mentioned as an alternative in the docs .