仅允许一次更新用户模型的属性

Question

管理员帐户会创建一个用户帐户，该帐户会自动生成一个由用户的名字和姓氏决定的用户名。 一旦创建了用户名，我希望用户只能更新一次-注意：这可以随时或多次登录后进行，但是一旦用户名更改，则需要将其设置为固定。

使用Rails和simple_form。 编辑表单如下。

= simple_form_for(current_user) do |f|
  = f.error_notification
  .form-inputs
    = f.input :name, required: true, label: 'Name'
    = f.input :username, required: true
    = f.input :email, required: true
    = f.input :password, required: true, placeholder: ("#{@minimum_password_length} characters minimum" if @minimum_password_length)
    = f.input :password_confirmation, required: true


  .form-actions
    = f.button :submit, "Update Profile", class: 'btn btn-primary btn-block btn-lg'

管理员/用户控制器。

  def create
    @user = User.new(user_params)
    @user.password = SecureRandom.base64()
    nameArray = @user.name.split(' ')
    @user.username = nameArray[0][0].downcase + nameArray[-1][0..6].downcase
    respond_to do |format|
      if @user.save
        @user.send_reset_password_instructions
        format.html do
          redirect_to [:admin, @user],
          notice: "#{@user} was successfully created. A confirmation email was sent to: #{@user.email}"
        end
      else
        format.html do
          flash[:alert] = "User #{@user} already exists, or you have not filled in all of the required fields."  
          render :new
        end
      end
    end
  end

提前致谢。

Answer 1

向用户添加新列，如：edited

def change
  add_column :users, :eited, :boolean, default: false
end

在模型用户中，在after_update之后添加calback

class User < ApplicationRecord
  after_update :set_edited!
  before_update :check_if_edited!

  def is_edited?
    edited?
  end

  private

  def check_if_edited!
    # there you can set the error message or what you want
    errors.add(:base, :invalid, message: "Your message")) if edited?
  end

  def set_edited!
    transaction do
      self.edited = true
      self.save!
    end
  end
end

在用户控制器中，添加限制以更新is_edited吗？

def update
  if current_user.is_edited?
    // preform action
  end
end

PS迁移逻辑以为模型用户分配属性

class User < ApplicationRecord
  after_create :assign_attributes

  private

  def assign_attributes
    transaction do
      self.password = SecureRandom.base64()
      name_array = name.split(' ')
      self.username = nameArray[0][0].downcase + nameArray[-1][0..6].downcase
     self.save!
    end
  end
end

Answer 2

我认为最好的方法是在用户模型中使用call_back：

before_update{|user|
  user.write_user_name_changed unless user.created_at == user.updated_at
}



 def write_user_name_changed
    self.user_name_changed = params[:username]
    true
  end