简单的投票系统在点击投票后不会将投票添加到数据库(Rails)？

Question

我找到了关于如何构建一个简单投票系统的教程。

我已经有了一个User和Post模型（只包括相关列），我正在使用Devise：

  create_table "posts", :force => true do |t|
    t.string   "content"
    t.integer  "user_id"
    t.string   "title"
    t.integer  "total_value",    :default => 0 // Added by following the tutorial 
  end
  create_table "users", :force => true do |t|
    t.string   "username"
  end

post.rb:

class Post < ActiveRecord::Base
  attr_accessible :title, :content
  belongs_to :user
  has_many :comments, :dependent => :destroy
  has_many :votes, :dependent => :destroy
end

user.rb:

class User < ActiveRecord::Base    
  has_many :posts, :dependent => :destroy
  has_many :comments, :dependent => :destroy   
end

投票.rb:

class Vote < ActiveRecord::Base
  belongs_to :post
end

迁移：

class CreateVotes < ActiveRecord::Migration
  def change
    create_table :votes do |t|
      t.integer :post_id
      t.integer :user_id
      t.boolean :value
      t.timestamps
    end
    add_index :votes, [:post_id, :user_id]
  end
end

votes_controller.rb：

class VotesController < ApplicationController
  def vote_up
    check = Votes.find(:first,
                       :conditions => ["user_id = ? AND post_id = ?", session[:user_id], params[:id]])
    post = Post.find(params[:id])
    if check.nil?
      vote = Votes.new
      vote.post_id = params[:id]
      vote.user_id = session[:user_id]
      vote.value = true
      vote.save
      post.total_value += 1
      post.save
      render :text => post.total_value
    elsif check.value == false
      check.value = true
      check.save
      post.total_value += 2
      post.save
      render :text => post.total_value
    else
      render :text => "You have already voted up for this post."
    end
  end
  def vote_down
    check = Vote.find(:first,
                      :conditions => ["user_id = ? AND post_id = ?", session[:user_id], params[:id]])
    post = Post.find(params[:id])
    if check.nil?
      vote = Vote.new
      vote.post_id = params[:id]
      vote.user_id = session[:user_id]
      vote.value = true
      vote.save
      post.total_value -= 1
      post.save
      render :text => post.total_value
    elsif check.value == true
      check.value = false
      check.save
      post.total_value -= 2
      post.save
      render :text => post.total_value
    else
      render :text => "You have already voted down for this post."
    end
  end
end

views/pages/index.html.erb:

<% for i in @posts %>
  <h2><%= i.title %></h2>
  <p><%= i.content %></p>
  <div id="total_value_<%= i.id %>"><%= i.total_value %></div>
  <%= link_to "Vote up",   :url => {:controller => :votes, :action => :vote_up, :id => i.id},
                           :update => "total_value_#{i.id}",
                           :remote => true %>
  <%= link_to "Vote down", :url => {:controller => :votes, :action => :vote_down, :id => i.id},
                           :update => "total_value_#{i.id}", 
                           :remote => true %>
<% end %>

一切都显示出来了，没有错误，但当我点击向上投票或向下投票时，绝对不会发生任何事情。

有什么建议可以解决这个问题吗？

编辑：

我没有看到任何错误，也没有在终端中保存/创建消息，只是这样的东西：

在开始获取127.0.0.1的"/assets/application.js？body=1"2012-02-01 06:47:50+0800已服务资产/应用程序.js-304未修改（0ms）〔2012-02-01 06:47:50〕WARN无法确定响应主体的内容长度。设置响应的内容长度或set响应#chunked=true

Answer 1

这可能是一个拼写错误，但你不应该有，Vote.new，Vote.find，

相反，您有Votes.fund和Votes.new

class VotesController < ApplicationController
  def vote_up
    check = Votes.find(:first,
                       :conditions => ["user_id = ? AND post_id = ?", session[:user_id], params[:id]])
    post = Post.find(params[:id])
    if check.nil?
      vote = Votes.new
      vote.post_id = params[:id]
      vote.user_id = session[:user_id]
      vote.value = true
      vote.save
      post.total_value += 1
      post.save
      render :text => post.total_value
    elsif check.value == false
      check.value = true
      check.save
      post.total_value += 2
      post.save
      render :text => post.total_value
    else
      render :text => "You have already voted up for this post."
    end
  end
  def vote_down
    check = Vote.find(:first,
                      :conditions => ["user_id = ? AND post_id = ?", session[:user_id], params[:id]])
    post = Post.find(params[:id])
    if check.nil?
      vote = Vote.new
      vote.post_id = params[:id]
      vote.user_id = session[:user_id]
      vote.value = true
      vote.save
      post.total_value -= 1
      post.save
      render :text => post.total_value
    elsif check.value == true
      check.value = false
      check.save
      post.total_value -= 2
      post.save
      render :text => post.total_value
    else
      render :text => "You have already voted down for this post."
    end
  end
end

将其更改为Vote.new和Vote.find并查看。

更新：

我建议您使用调试器gem。另一个建议是使用gem来实现此功能。为此创造了大量的宝石。vote_fu和acts_as_votable是使用最多的两个。