ROR：向用户表添加列：未经允许的参数

Question

我是 Rails 新手，所以请原谅我不太好的解释。我正在使用宝石设计。我已正确设置电子邮件和密码。我现在想添加一个用户名。所以我所做的是：

rails g migration AddUserNameToUsers Username:string

  invoke  active_record
  create    db/migrate/20170203113948_add_user_name_to_users.rb

然后：

rails db:migrate
== 20170203113948 AddUserNameToUsers: migrating   
-- add_column(:users, :Username, :string)
-> 0.0017s
== 20170203113948 AddUserNameToUsers: migrated (0.0024s) 

然后我检查它是否已添加到用户表中：

sqlite> select * from users;
13|Username|varchar|0||0

然后我设置设计注册视图以包含用户名：

<div class="form-group">
                <%= f.label :email %><br />
                <%= f.email_field :email, autofocus: true, class: "form-control" %>
              </div>

               <div class="form-group">
                <%= f.label :Username %><br />
                <%= f.text_field :Username, autofocus: true, class: "form-control" %>
              </div>

              <div class="form-group">
                <%= f.label :password %> <% if @validatable %><i>(<%= @minimum_password_length %> characters minimum)</i><% end %><br />
                <%= f.password_field :password, autocomplete: "off", class: "form-control" %>
              </div>

              <div class="form-group">
                <%= f.label :password_confirmation %><br />
                <%= f.password_field :password_confirmation, autocomplete: "off", class: "form-control" %>
              </div>

              <div class="form-group">
                <%= f.submit "Sign up", class: "btn btn-primary" %>
              </div>
            <% end %>

当我提交表单但未添加用户名时，页面返回时没有错误。日志显示：

Started POST "/users" for ::1 at 2017-02-03 12:43:40 +0000
Processing by Devise::RegistrationsController#create as HTML
Parameters: {"utf8"=>"✓",     "authenticity_token"=>"MfdDSafryl0mnHM3BzEtxkOoImZXUm7rfcq2sYrNaltD2S8i3SvFCRdMqam9ukEZXcY23zF/NpY/LPyj6tJm2A==", "user"=>{"email"=>"joe@test.com", "Username"=>"james", "password"=>"[FILTERED]", "password_confirmation"=>"[FILTERED]"}, "commit"=>"Sign up"}
 Unpermitted parameter: Username

Answer 1

class ApplicationController < ActionController::Base
  before_filter :configure_permitted_parameters, if: :devise_controller?

  protected

  def configure_permitted_parameters
    devise_parameter_sanitizer.permit(:sign_up, keys: [:username])
  end
end