我正在使用rails(5.1.4)并尝试显示标记为特定类别的所有帖子。我目前只能返回一个帖子,而不是每个帖子都有这个类别。
Post.rb
has_many :post_categories
has_many :categories, through: :post_categories
extend FriendlyId
friendly_id :title, use: :slugged
def category_list
categories.map(&:name)
end
Category.rb:
class Category < ApplicationRecord
has_many :post_categories
has_many :posts, through: :post_categories
extend FriendlyId
friendly_id :name, use: :slugged
end
类别控制器:
def show
@category = Category.find_by_name(params[:category])
@posts = @category.posts
end
类别#show ERB :(我试图列出这个类别的每个帖子,但只获得一个结果,当我可以看到很多相同类别的帖子时)
<% @posts.each do |post| %>
<h1 class="title"><%= link_to post.title, post_path(post) %></h1>
<% end %>
从终端:
Started GET "/category/Philadelphia%20maki" for 127.0.0.1 at 2017-12-17 21:03:39 -0800
Processing by CategoriesController#show as HTML
Parameters: {"category"=>"Philadelphia maki"}
Category Load (5.6ms) SELECT "categories".* FROM "categories" WHERE "categories"."name" = $1 LIMIT $2 [["name", "Philadelphia maki"], ["LIMIT", 1]]
Rendering categories/show.html.erb within layouts/dashboards
Post Load (2.0ms) SELECT "posts".* FROM "posts" INNER JOIN "post_categories" ON "posts"."id" = "post_categories"."post_id" WHERE "post_categories"."category_id" = $1 [["category_id", 15]]
路线:
category GET|POST /category/:category(.:format) categories#show
帖子#show ERB:
<ul class="category-list">
<% @post.category_list.map.each do |category| %></p>
<li itemprop="genre" class="category-list-item"> <%= link_to "#{category}", category_path(category) %></li>
<% end %>
</ul>
对于访问此页面的用户,
问题
用户在不同的页面上看到多个具有相同类别名称的帖子,但在获取该类别的帖子时,它只返回1个帖子。
原因
数据库中有多个Category
记录具有相同的名称。
解
为模型Category
添加验证:
validates :name, uniqueness: true, allow_blank: true