nameerror未定義的局部變量或方法`log_out'您的意思是？在軌道上

Question

所以我下面的tutorial由邁克爾·哈特爾，當我試圖註銷logout_url紅寶石，我得到這個 "NameError in SessionsController#destroy"undefined local variable or method "log_out" for #<SessionsController:0x0000000275f290> Did you mean? logout_url

我的測試中，該錯誤只彈出後，我在我的測試中添加的最後一位但是，我在網站上的註銷功能也不起作用。

這是我session_helper.rb：

module SessionsHelper 

    # Logs in the given user. 
    def log_in(user) 
    session[:user_id] = user.id 
    end 

    # Returns the current logged-in user (if any). 
    def current_user 
    @current_user ||= User.find_by(id: session[:user_id]) 
    end 

    # Returns true if the user is logged in, false otherwise. 
    def logged_in? 
    !current_user.nil? 
    end 

# Logs out the current user. 
    def destroy 
    session.delete(:user_id) 
    @current_user = nil 
    end 
end 

這是我session_controller：

class SessionsController < ApplicationController 
    def new 
    end 

    def create 
    #Gets user from database in lowercase & determines if user is valid 
    user = User.find_by(email: params[:session][:email].downcase) 
    if user && user.authenticate(params[:session][:password]) 
     # Log the user in and redirect to the user's show page. 
     log_in user 
     redirect_to user 
    else 
     # Create an error message. 
     flash.now[:danger] = 'Invalid email/password combination' 
     render 'new' 
    end 
    end 

    # Logs out the current user. 
    def destroy 
    log_out # undefined variable Name error 
    redirect_to root_url 
    end 
end 

我application_controller：

class ApplicationController < ActionController::Base 
    protect_from_forgery with: :exception 
    include SessionsHelper #temporary session cookie, expires automatically upon browser close 
    end 

我的看法/佈局/ _header.html.erb （用於註銷鏈接的導航欄）：

<header class="navbar navbar-fixed-top navbar-inverse"> 
    <div class="container"> 
    <%= link_to image_tag("logo2.png", alt: "CourseBuddies logo"), root_path, id: "logo" %> 
    <%- # link_to "sample app", '#', id: "logo" %> 
    <nav> 
     <ul class="nav navbar-nav navbar-right"> 
     <li><%= link_to "Home", root_path %></li> 
     <li><%= link_to "Reviews", '#' %></li> 
     <li><%= link_to "About us", about_path %></li> 

     <%- # LOGIN & SCROLL DOWN BAR %> 
     <% if logged_in? %> 
      **<li><%= link_to "Users", users_path %></li> 
      <li class="dropdown">** 
      <a href="#" class="dropdown-toggle" data-toggle="dropdown"> 
       Account <b class="caret"></b> 
      </a> 
      <ul class="dropdown-menu"> 
       **<li><%= link_to "Profile", current_user %></li> 
       <li><%= link_to "Settings", '#' %></li>** 
       <li class="divider"></li> 
       <li> 
       **<%= link_to "Log out", logout_path, method: :delete %>** 
       </li> 
      </ul> 
      </li> 
     **<% else %> 
      <li><%= link_to "Log in", login_path %></li> 
     <% end %>** 
     </ul> 
    </nav> 
    </div> 
</header> 

我的用戶模型：

class User < ApplicationRecord 
    #before saving, make sure the email is in downcase 
    before_save { self.email = email.downcase } 

    validates :name, presence: true, length: { maximum: 50 } 
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i 
    validates :email, presence: true, length: { maximum: 255 }, 
        format: { with: VALID_EMAIL_REGEX }, 
        uniqueness: {case_sensitive: false} 


    # Let's you safely store a hashed password_digest to DB, 
    # gives you password & password_confirmation attributes, 
    # an authenticate method that returns the user when pw is correct, 
    # otherwise false. 
    has_secure_password(validations:false) 
    validates :password, presence:true, length: { minimum: 6 } 

    # Returns the hash digest of the given string. 
    def User.digest(string) 
     cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST : 
                BCrypt::Engine.cost 
     BCrypt::Password.create(string, cost: cost) 
    end 
end 

我在我的用戶控制器創建-方法： DEF創建 @user = User.new（user_params）#params [：用戶]）＃user_params）

if @user.save 
    log_in @user 
    flash[:success] = "Welcome to CourseBuddies!" 
    redirect_to @user 

else 
    render 'new' 
end 

末

我的測試/ test_helper：

ENV['RAILS_ENV'] ||= 'test' 
require File.expand_path('../../config/environment', __FILE__) 
require 'rails/test_help' 
require "minitest/reporters" 
Minitest::Reporters.use! 

class ActiveSupport::TestCase 
    # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order. 
    fixtures :all 

    # Returns true if a test user is logged in. 
    def is_logged_in? 
    !session[:user_id].nil? 
    end 
end 

而且我user_login_test：

require 'test_helper' 

class UsersLoginTest < ActionDispatch::IntegrationTest 

    def setup 
    @user = users(:michael) 
    end 

    # Visit the login path. 
# Verify that the new sessions form renders properly. 
# Post to the sessions path with an invalid params hash. 
# Verify that the new sessions form gets re-rendered and that a flash message appears. 
# Visit another page (such as the Home page). 
# Verify that the flash message doesn’t appear on the new page. 
    test "login with valid information followed by logout" do 
    get login_path 
    post login_path, params: { session: { email: @user.email, 
             password: 'password' } } 
    assert is_logged_in? 
    assert_redirected_to @user 
    follow_redirect! 
    assert_template 'users/show' 
    assert_select "a[href=?]", login_path, count: 0 
    assert_select "a[href=?]", logout_path 
    assert_select "a[href=?]", user_path(@user) 

    #AFTER ADDING THIS MY TEST FAILED 

    #after logging in, we use delete to issue a DELETE request to the logout path 
    #(Table 8.1) and verify that the user is logged out and redirected to the root URL 
    delete logout_path 
    assert_not is_logged_in? 
    assert_redirected_to root_url 
    follow_redirect! 
    assert_select "a[href=?]", login_path 
    assert_select "a[href=?]", logout_path,  count: 0 
    assert_select "a[href=?]", user_path(@user), count: 0 
    end 
end 

最後

我的路線：

Rails.application.routes.draw do 

    get 'sessions/new' 

    #ROOT, first page to show 
    root 'pages#home' 

    # maps requests for the URL/pages/home to the about us action in the Pages controller. 
    # By using GET we arrange for the route to respond to a GET request. 
    # With this we generate a about us action inside the Pages controller, automatically 
    # get a page at the address /pages/about us 
    get '/about', to: 'pages#about' 
    get '/signup', to: 'users#new' 
    post '/signup', to: 'users#create' #signup route that responds to POST requests. 
    get '/login', to: 'sessions#new' 
    post '/login', to: 'sessions#create' 
    delete '/logout', to: 'sessions#destroy' 

    #resources :sessions 
    resources :users 
    # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html    

end 

對不起有很多的代碼！在教程中，它表示在添加新代碼後，測試users_login_test應該變爲綠色，但失敗。此外，註銷不起作用，並給我這個錯誤： image of error

我將不勝感激任何幫助！

Answer 1

NameError in SessionsController#destroy"undefined local variable or method "log_out" for SessionsController:0x0000000275f290 Did you mean? logout_url

在教程（參見8.3），在方法名在sessions_helper爲log_out，而你把它命名爲destroy，但稱它作爲sessions_controllerlog_out。您應該將其更改爲log_out

def log_out 
    session.delete(:user_id) 
    @current_user = nil 
end