当我尝试使用user.save时,为什么我的rails会回滚？

Question

我已经安装了RailsTutorial示例应用程序(类似应用程序的推特),并且我试图理解为什么当我尝试更新用户数据库时,下面的控制台代码不会更新数据库.我期待用户信息在我使用后得到更新user.save.但是,这会回滚到未经编辑的数据.这是由于基于用户的限制吗？

用户控制器:

class UsersController < ApplicationController

#before_filter :signed_in_user, only: [:index, :edit, :update, :destroy, :following, :followers]
# By default before filters apply to all actions
#before_filter :correct_user, only: [:edit, :update]
  def edit
    @user = User.find(params[:id])
  end

  def update

    @user = User.find params[:id]

    respond_to do |format|

    if @user.update_attributes(params[:user])
      flash[:notice] = "Profile updated"
      format.html { redirect_to(@user, :notice => 'User was successfully updated.') }
      format.json { respond_with_bip(@user) }
    else

      format.html { render :action => "edit" }
      format.json { respond_with_bip(@user) }
    end
    end
 end

  private


  def correct_user
    @user = User.find(params[:id])
    redirect_to(root_path) unless current_user?(@user)
  end

  def admin_user
    redirect_to(root_path) unless current_user.admin?
  end


end

Rails控制台:

1.9.3-p392 :001 > user = User.find(109)


User Load (8.2ms)  SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT 1  [["id", 109]]
 => #<User id: 109, name: "laurie", email: "auriepage@gmail.com", created_at: "2013-09-26 18:10:12", updated_at: "2013-09-26 18:10:12", password_digest: "$2a$10$aXEtun8Z2Deqy2wNxvFRNOjPczKQkYc1vDezP5OduJuF...", remember_token: "YhIUhgFm9iMewxdNOHJ45A", admin: false> 

1.9.3-p392 :002 > user.name = "larry"
 => "larry" 

1.9.3-p392 :003 > user.save
   (0.2ms)  begin transaction
  User Exists (0.6ms)  SELECT 1 AS one FROM "users" WHERE (LOWER("users"."email") = LOWER('auriepage@gmail.com') AND "users"."id" != 109) LIMIT 1
   (0.1ms)  rollback transaction
 => false 

用户模型:

class User < ActiveRecord::Base

# Declaration of public variables   
  attr_accessible :email, :name, :password, :password_confirmation
  has_secure_password
  has_many :microposts, dependent: :destroy
  has_many :relationships, foreign_key: "follower_id", dependent: :destroy
  has_many :followed_users, through: :relationships, source: :followed
  has_many :reverse_relationships, foreign_key: "followed_id", class_name: "Relationship", dependent: :destroy
  has_many :followers, through: :reverse_relationships, source: :follower

  before_save {email.downcase!}
  before_save :create_remember_token

  validates :name, presence: true, length: {maximum: 50}
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, format: {with: VALID_EMAIL_REGEX}, uniqueness: {case_sensitive: false}
  validates :password, presence: true, length: {minimum: 6}
  validates :password_confirmation, presence: true
  after_validation {self.errors.messages.delete(:password_digest)}

 private
    def create_remember_token
        self.remember_token = SecureRandom.urlsafe_base64
    end
end

Answer 1

您的用户模型可能具有不满足的验证.由于你没有发布那些我无法真正解决你的问题.为了简化操作,您可以调试用户不愿意保存的原因.

试试跑步

user.errors.full_messages

哪个应该给你一个提示出了什么问题.

Answer 2

我知道这是一篇很老的帖子,但希望这有助于将来有人通过本教程.

如所接受的答案所表达的,这是由于不满足的验证.我也遇到了这个问题,并发现另一种解决方法是update_attribute在user对象上使用该方法.例如,如果要更新对象的name字段user并将其自动保存到数据库,而不必触摸虚拟password和password_confirmation字段,请使用以下命令:

user.update_attribute(:name, "larry")

这将name仅更新字段并将其保存到数据库(无需调用save方法),而无需触及password和password_confirmation字段.

Answer 3

尝试保存或验证活动记录模型实例后,您可以查看有关一些有用命令所发生情况的更多信息.

user = User.find(108)
user.name = "Larry"
user.valid? # returns false
user.errors.messages # returns something like {email: "Cant be blank"}

显然我犯了这个错误,因为我不知道你的模型文件是什么样的,但是如果它的角色通常是由于两个原因之一.首先是您的验证失败.如果它们没有错误消息,可能是因为过滤器链中的某些内容返回false.例如

class User << ActiveRecord::Base
  before_save :accidentally_return_false

  def accidentally_return_false
    self.some_boolean = (condition == value)
  end
end

user = User.new( params )
user.save # where condition does not equal value
user.valid? # false because of the before save method

希望有所帮助

Answer 4

保存回滚时,使用保存!相反,将打印错误日志.

Answer 5

您的验证未通过。你可以做：

user.errors.full_messages

保存失败后在控制台中查看原因。