设计强大的参数

Question

我正在尝试在我的 rails 4 项目之一中实施设计，但遇到了一个奇怪的错误。当我跑步时：

rake db:migrate

我得到以下信息：

rake aborted!
NameError: undefined local variable or method `params' for User (call 'User.connection' to establish a connection):Class
/home/zach/.rvm/gems/ruby-2.1.2/gems/activerecord-4.1.4/lib/active_record/dynamic_matchers.rb:26:in `method_missing'
/home/zach/HandCoOp/project/HandCo-op/app/models/user.rb:8:in `<class:User>'
/home/zach/HandCoOp/project/HandCo-op/app/models/user.rb:1:in `<top (required)>'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:443:in `load'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:443:in `block in load_file'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:633:in `new_constants_in'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:442:in `load_file'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:342:in `require_or_load'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:480:in `load_missing_constant'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:180:in `const_missing'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/inflector/methods.rb:238:in `const_get'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/inflector/methods.rb:238:in `block in constantize'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/inflector/methods.rb:236:in `each'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/inflector/methods.rb:236:in `inject'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/inflector/methods.rb:236:in `constantize'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:552:in `get'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:583:in `constantize'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:297:in `get'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:77:in `to'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:72:in `modules'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:89:in `routes'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:156:in `default_used_route'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/mapping.rb:66:in `initialize'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:331:in `new'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise.rb:331:in `add_mapping'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:221:in `block in devise_for'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:220:in `each'
/home/zach/.rvm/gems/ruby-2.1.2/gems/devise-3.2.4/lib/devise/rails/routes.rb:220:in `devise_for'
/home/zach/HandCoOp/project/HandCo-op/config/routes.rb:2:in `block in <top (required)>'
/home/zach/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.4/lib/action_dispatch/routing/route_set.rb:337:in `instance_exec'
/home/zach/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.4/lib/action_dispatch/routing/route_set.rb:337:in `eval_block'
/home/zach/.rvm/gems/ruby-2.1.2/gems/actionpack-4.1.4/lib/action_dispatch/routing/route_set.rb:315:in `draw'
/home/zach/HandCoOp/project/HandCo-op/config/routes.rb:1:in `<top (required)>'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:241:in `load'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:241:in `block in load'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:232:in `load_dependency'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:241:in `load'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:40:in `each'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:40:in `load_paths'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:16:in `reload!'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:26:in `block in updater'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/file_update_checker.rb:75:in `call'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/file_update_checker.rb:75:in `execute'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:27:in `updater'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application/finisher.rb:71:in `block in <module:Finisher>'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/initializable.rb:30:in `instance_exec'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/initializable.rb:30:in `run'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/initializable.rb:55:in `block in run_initializers'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/initializable.rb:54:in `run_initializers'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application.rb:300:in `initialize!'
/home/zach/HandCoOp/project/HandCo-op/config/environment.rb:5:in `<top (required)>'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:247:in `require'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:247:in `block in require'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:232:in `load_dependency'
/home/zach/.rvm/gems/ruby-2.1.2/gems/activesupport-4.1.4/lib/active_support/dependencies.rb:247:in `require'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application.rb:276:in `require_environment!'
/home/zach/.rvm/gems/ruby-2.1.2/gems/railties-4.1.4/lib/rails/application.rb:379:in `block in run_tasks_blocks'
/home/zach/.rvm/gems/ruby-2.1.2/bin/ruby_executable_hooks:15:in `eval'
/home/zach/.rvm/gems/ruby-2.1.2/bin/ruby_executable_hooks:15:in `<main>'
Tasks: TOP => db:migrate => environment
(See full trace by running task with --trace)

这是我的模型，错误指向“params.require”，根据强参数，它应该是实心的。

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

  # Setup accessible (or protected) attributes for your model
  params.require(:email, :password, :password_confirmation)
end

有人知道发生了什么吗？也许我错过了强参数所需的宝石？我只是不知道。我会继续调查这个问题，并感谢任何知道我错误的人。

Answer 1

您是否了解如何使用强参数？从模型中删除此 params.require(:email, :password, :password_confirmation) 行。

在你的控制器中（假设users_controller.rb）：

def create 
  @user = User.new(user_params)
end

然后在文件的底部：

 private
    def user_params
      params.require(:user).permit(:email, :password, :password_confirmation)
    end

在你的控制器中定义了这个，你的 create 方法就可以工作了。