Michael Hartl的Rails教程第8章。未創建用戶會話

Question

我正在練習Michael Hartl的Rails教程第8章。

我有以下部分標題。

<header class="navbar navbar-fixed-top navbar-inverse">
  <div class="navbar-inner">
    <div class="container">
      <%= link_to "sample app", root_path, id: "logo" %>
      <nav>
        <ul class="nav pull-right">
          <li><%= link_to "Home", root_path %></li>
          <li><%= link_to "Help", help_path %></li>
          <% if signed_in? %>
              <li><%= link_to "Users", '#' %></li>
              <li id="fat-menu" 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 "Sign out", signout_path, method: "delete" %>
                  </li>
                </ul>
              </li>
          <% else %>
              <li><%= link_to "Sign in", signin_path %></li>
          <% end %>
        </ul>
      </nav>
    </div>
  </div>
</header>

和下面的會話控制器

def new
  end

  def create
    user = User.find_by_email(params[:session][:email].downcase)
    if user && user.authenticate(params[:session][:password])
      sign_in user
      redirect_to user
    else
      flash.now[:error] = 'Invalid email/password combination'
      render 'new'
    end
  end

  def destroy
    sign_out
    redirect_to root_url
  end

會話助手

def sign_in(user)
    cookies.permanent[:remember_token] = user.remember_token
    self.current_user = user
  end

  def signed_in?
    !current_user.nil?
  end

  def current_user=(user)
    @current_user = user
  end

  def current_user
    @current_user ||= User.find_by_remember_token(cookies[:remember_token])
  end

  def sign_out
    self.current_user = nil
    cookies.delete(:remember_token)
  end

用戶模型

class User < ActiveRecord::Base
  attr_accessible :name, :email, :password, :password_confirmation
  has_secure_password
  before_save :create_remember_token
  before_save { |user| user.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,
            format:     { with: VALID_EMAIL_REGEX },
            uniqueness: { case_sensitive: false }
  validates :password, presence: true, length: { minimum: 6 }
  validates :password_confirmation, presence: true

  private
    def create_remember_token
    self.remember_token = SecureRandom.urlsafe_base64
  end
end

現在，當我登錄用戶並嘗試查看下拉菜單時，我將其添加到標題部分。 我看不到。 當我調試代碼時，我看到這是因為，用戶會話未創建，並且如果不是<% if signed_in? %> ，它不會從<% if signed_in? %> <% if signed_in? %>條件在標題部分中。

Answer 1

好的，我解決了問題。 方法

    def signed_in?
    !current_user.nil?
  end

在session_helper中不應包含“！” 符號。