ruby-on-rails - # 的未定义方法 `user_signed_in?'

Question

我想用 Ruby on Rails 进行身份验证，每个用户都有自己的帐户。但是现在我得到了这个错误:

undefined method user_signed_in? for #<ProjectsController:0x007faead1853e0>

有人能帮帮我吗？

代码如下:

完整跟踪:

app/controllers/projects_controller.rb:69:in `require_login'
activesupport (3.2.3) lib/active_support/callbacks.rb:418:in `_run__2505248868868045404__process_action__114470166732456289__callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.3) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.3) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.3) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.3) lib/action_controller/metal/params_wrapper.rb:205:in `process_action'
activerecord (3.2.3) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.3) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.3) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.3) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.3) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.3) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.3) lib/journey/router.rb:68:in `block in call'
journey (1.0.3) lib/journey/router.rb:56:in `each'
journey (1.0.3) lib/journey/router.rb:56:in `call'
actionpack (3.2.3) lib/action_dispatch/routing/route_set.rb:600:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.1) lib/rack/etag.rb:23:in `call'
rack (1.4.1) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.1) lib/rack/session/abstract/id.rb:205:in `context'
rack (1.4.1) lib/rack/session/abstract/id.rb:200:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/cookies.rb:338:in `call'
activerecord (3.2.3) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:467:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `_run__4031929640367205598__call__2058268190974805736__callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.3) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.3) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.3) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.3) lib/rails/rack/logger.rb:26:in `call_app'
railties (3.2.3) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.1) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.1) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.1) lib/rack/lock.rb:15:in `call'
actionpack (3.2.3) lib/action_dispatch/middleware/static.rb:62:in `call'
railties (3.2.3) lib/rails/engine.rb:479:in `call'
railties (3.2.3) lib/rails/application.rb:220:in `call'
rack (1.4.1) lib/rack/content_length.rb:14:in `call'
railties (3.2.3) lib/rails/rack/log_tailer.rb:14:in `call'
rack (1.4.1) lib/rack/handler/webrick.rb:59:in `service'
/Users/sinaoberle/.rbenv/versions/1.9.3-p0/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
/Users/sinaoberle/.rbenv/versions/1.9.3-p0/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
/Users/sinaoberle/.rbenv/versions/1.9.3-p0/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'

projects_controller.rb

class ProjectsController < ApplicationController
  before_filter :require_login
  # GET /projects
  # GET /projects.json
  def index
    @projects = current_user.projects

  end

  # GET /projects/1
  # GET /projects/1.json
  def show
    @projects = current_user.projects.find(params[:id])

  end

  # GET /projects/new
  # GET /projects/new.json
  def new
    @projects = current_user.projects.build

  end

  # GET /projects/1/edit
   def show
    @projects = current_user.projects.find(params[:id])

  end

  # POST /projects
  # POST /projects.json
  def create
    @projects = current_user.projects.build(params[:mytime])
      if @projects.save
         redirect_to projects_path,
            notice: 'Created successfully!'
      else
        render 'new'
      end
     end 

  # PUT /projects/1
  # PUT /projects/1.json
  def update
    @projects = current_user.projects.find(params[:id])
      if @projects.update_attributes(params[:mytime])
        redirect_to projects_path,
            notice: 'Changed successfully!'
      else
        render 'edit'

   end
 end

  # DELETE /projects/1
  # DELETE /projects/1.json
  def destroy
    @projects = current_user.projects.find(params[:id])
    @projects.destroy
    redirect_to projects_url,
        notice: 'Deleted successfully!'

  end
end 

private

def require_login
  unless user_signed_in?
    redirect_to login_path,
    alert: "Please, Sign In first!"
end 
end 

application.html.erb

<!DOCTYPE html>
<html>
<head>
  <title>Test</title>
  <%= stylesheet_link_tag    "application", :media => "all" %>
  <%= javascript_include_tag "application" %>
  <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>


  <%= csrf_meta_tags %>
</head>
<body>
<div id="container">

    <div id="content">
        <% if flash[:notice] %>
        <p id="notice">
            <%= flash[:notice] %>
        </p>
        <% end %>

        <% if flash[:alert] %>
        <p id= "alert">
            <%= flash[:alert] %> 
        </p>
        <% end %>
    </div>
    <div id="footer">
    <%= link_to "Sign In", new_user_path %> |
        <% if user_signed_in? %>
        <%= link_to "Logout", logout_path, method: :delete %> |
        <%= link_to "Test", projects_path %>
        <% else %>
        <%= link_to "Login", login_path %>
        <% end %> 
        <%= yield %>
    </div>
</div>
</body>
</html>

routes.rb

项目::Application.routes.draw 做

  get "pages/home"

  resources :projects
  resources :users, :only => [:new, :create]
  resources :sessions, :only => [:create]

  get "login" => "sessions#new", as: "login"
  post "sessions" => "sessions#create", as: "sessions"
  delete "logout" => "sessions#destroy", as: "logout"

  root to: 'pages#home'

Answer 1

您是否正在使用设备进行身份验证？我自己没有使用过它，但通过查看 devise code和 documentation看起来你应该在 Controller (或某些父 Controller 类)中执行 before_filter :authenticate_user!，你想在其中使用像 user_signed_in? 这样的助手。

请注意，从 Rails 5.1 开始，您必须改用 before_action。