+@import "bootstrap-sprockets";
+@import "bootstrap";

@import "font-awesome";

   + belongs_to :user
   + belongs_to :product
```   

``` ruby app/models/product.rb

   + has_many :collects
   + has_many :collected_users, through: :collects, source: :user

   + has_many :collects
   + has_many :collected_products, through: :collects, source: :product

   #加上是否收藏商品的判定
   + def is_collect_of?(product)
   +  collected_products.include?(product)
   + end
```    

#### step2
首先修改路由信息：
``` ruby config/routes.rb

  + resources :product do
   +  member do
   +    post :collect
   +    post :uncollect
   + end
 +  end

+ def	collect
 + @product = Product.find(params[:id])
 + current_user.collected_products << @product
 + flash[:notice] = "成功收藏商品"
 + redirect_to :back
+ end

+ def uncollect
 + @product = Product.find(params[:id])
 + currrent_user.collected_products.delete(@product)
 + flash[:warning] = "您已取消收藏该商品"
 + redirect_to :back
+ end

+ <% if current_user && current_user.is_collect_of?(@product) %>
+  <%= link_to(“取消收藏”, uncollect_product_path(@product), :method => :post, class: "btn btn-danger btn-lg" )%>
+ <% else %>
+  <%= link_to("收藏“, collect_product_path(@product), :method => :post, class: "btn btn-danger btn-lg" )%>
+ <% end %>

  class CreateCollects < ActiveRecord::Migration[5.0]
    def change
      create_table :collects do |t|
+       t.integer :user_id, :index => true
+       t.integer :product_id, :index => true
        t.timestamps
      end
    end
  end

+ belongs_to :user
+ belongs_to :product

  + has_many :collects, :dependent => :destroy
  + had_many :collected_users, through: :collects, source: :user

  + def find_collect(user)
   +  self.collects.where( :user_id => user.id).first
  + end
```  

编辑 `app/model/user.rb`,加上关联
``` ruby app/models/user.rb
  +  has_many :collects, :dependent => :destroy
  +  has_many :collected_products, through: :collects,  source: :product

+ resource :products do
+   member do
+     post :collect
+     post :uncollect
+   end
+ end

+ def collect
  + @product = Product.find(params[:id])    
  + unless @product.find_collect(cuurent_user)
  +   Collect.create( :user => current_user, :product => @product)
  + flash[:notice] = "您已成功收藏该商品"
  + end
  + redirect_to :back
+ end

+ def uncollect
   + @product = Product.find(params[:id])
   + collect = @product.find_collect(current_user)
   + collect.destroy
   + flash[:warning] = "您已取消收藏该商品"
   + redirect_to :back
+ end

……略
 + <% if current_user %>
 +   <% if @product.find_collect(current_user)%>
 +     <% =link_to("取消收藏", uncollect_product_path(@product), :method => :post, class: "btn btn-danger btn-lg")%>
 +   <% else %>
 +     <%= link_to("收藏", collect_product_path(@product), :method => :post, class: "btn btn-primary btn-lg")%>
 +   <% end %>
 + <% end %>
……略

+  gem 'ransack'

  Rails.application.routes.draw do
    devise_for :users
    resources :posts do
   +   collection do    #我们会搜索出所有符合关键字的文章，结果为复数，因此用collection，而不是member
   +     get :search
   +   end
    end
  end  
```  

#### 2、设置controller
主要设置通过哪些关键词进行搜索。
```ruby app/controllers/posts_controller.rb

  class PostsController < ApplicationController
    before_action :validate_search_key, only: [:search]

    def search
      if @query_string.present?
        @posts = search_params    #搜索post的关键词
      end
    end

    protected  # 放在最后

    def validate_search_key
       # gsub 是Ruby中正则表达式的方法，它会切换所有匹配到的部分
       @query_string = params[:q].gsub(/\\|\'|\/|\?/, "")if params[:q].present?  
    end

    def search_params      
      Post.ransack({:title_or_content_cont => @query_string}).result(distinct: true)
      #title与content是post的两个栏位，而我们的关键词出自这里
      end
  end

 <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
 +  <ul class="nav navbar-nav">
 +    <li>
 +        <div class="form-group form-inline search-bar">
 +          <%= render :partial => "posts/search_bar"%>
 +       </div>
 +      </li>
 +  </ul>
 …… 略
</div>

 <div class="row">
  <div class="col-sm-9 col-lg-8 col-lg-offset-2">
    <%= form_tag search_posts_path, :class => "posts-search-form", :method => :get do %>
      <div class="input-group">
        <input type="text" class="form-control search-bar-input" name="q" value="<%= params[:q] %>" placeholder="关键词">
        <span class="input-group-btn">
          <button type="submit" class="btn btn-default search-bar-submit">
            <span class="glyphicon glyphicon-search"></span>
          </button>
        </span>
      </div>
    <% end %>
  </div>
</div>

<div class="minHeight1000 bg-gray">
  <div class="search-page w1200 pt30 bc">
      <% if @posts.present? %>
        <h5 class="collection search-count">已为您找到<%= @posts.count %>篇相关文章</h5>
      <% else %>
        <p class="tc mt100">未搜索到任何文章，要不换个关键词试试？</p>
      <% end %>
  </div>

  <div class="container">
  <% @posts.each do |post| %>

    <div class="panel panel-default">
      <div class="panel-body">
        <%= post.title %>
        <br/>
        <br/>
        <span id="psot-thumbsup-<%= post.id%>" class=" label label-success"><%= post.likes.count%>👍</span>
        <div class="text-right">

          <% if !current_user.is_collect_of?(post) %>
            <%= link_to("收藏", collect_post_path(post), method: :post, class: "btn btn-sm") %>
          <% else %>
            <%= link_to("取消收藏", uncollect_post_path(post), method: :post, class: "btn btn-sm") %>
          <% end %>
        </div>
      </div>

    </div>

  <% end %>
  </div>
</div>