在我的Rails 4应用程序中，有四种模式：
class User < ActiveRecord::Base
has_many :administrations
has_many :calendars, through: :administrations
end
class Calendar < ActiveRecord::Base
has_many :administrations
has_many :users, through: :administrations
has_many: :posts
end
class Administration < ActiveRecord::Base
belongs_to :user
belongs_to :calendar
end
class Post < ActiveRecord::Base
belongs_to :calendar
end
使用此路由：
Rails.application.routes.draw do
root to: 'pages#home'
devise_for :users, :path => 'account'
resources :calendars do
resources :posts, shallow: true
end
end
这给出了这些路线：
Prefix Verb URI Pattern Controller#Action
posts GET /posts(.:format) posts#index
POST /posts(.:format) posts#create
new_post GET /posts/new(.:format) posts#new
edit_post GET /posts/:id/edit(.:format) posts#edit
post GET /posts/:id(.:format) posts#show
PATCH /posts/:id(.:format) posts#update
PUT /posts/:id(.:format) posts#update
DELETE /posts/:id(.:format) posts#destroy
root GET / pages#home
new_user_session GET /account/sign_in(.:format) devise/sessions#new
user_session POST /account/sign_in(.:format) devise/sessions#create
destroy_user_session DELETE /account/sign_out(.:format) devise/sessions#destroy
user_password POST /account/password(.:format) devise/passwords#create
new_user_password GET /account/password/new(.:format) devise/passwords#new
edit_user_password GET /account/password/edit(.:format) devise/passwords#edit
PATCH /account/password(.:format) devise/passwords#update
PUT /account/password(.:format) devise/passwords#update
cancel_user_registration GET /account/cancel(.:format) devise/registrations#cancel
user_registration POST /account(.:format) devise/registrations#create
new_user_registration GET /account/sign_up(.:format) devise/registrations#new
edit_user_registration GET /account/edit(.:format) devise/registrations#edit
PATCH /account(.:format) devise/registrations#update
PUT /account(.:format) devise/registrations#update
DELETE /account(.:format) devise/registrations#destroy
user_confirmation POST /account/confirmation(.:format) devise/confirmations#create
new_user_confirmation GET /account/confirmation/new(.:format) devise/confirmations#new
GET /account/confirmation(.:format) devise/confirmations#show
user_unlock POST /account/unlock(.:format) devise/unlocks#create
new_user_unlock GET /account/unlock/new(.:format) devise/unlocks#new
GET /account/unlock(.:format) devise/unlocks#show
calendar_posts GET /calendars/:calendar_id/posts(.:format) posts#index
POST /calendars/:calendar_id/posts(.:format) posts#create
new_calendar_post GET /calendars/:calendar_id/posts/new(.:format) posts#new
GET /posts/:id/edit(.:format) posts#edit
GET /posts/:id(.:format) posts#show
PATCH /posts/:id(.:format) posts#update
PUT /posts/:id(.:format) posts#update
DELETE /posts/:id(.:format) posts#destroy
calendars GET /calendars(.:format) calendars#index
POST /calendars(.:format) calendars#create
new_calendar GET /calendars/new(.:format) calendars#new
edit_calendar GET /calendars/:id/edit(.:format) calendars#edit
calendar GET /calendars/:id(.:format) calendars#show
PATCH /calendars/:id(.:format) calendars#update
PUT /calendars/:id(.:format) calendars#update
DELETE /calendars/:id(.:format) calendars#destroy
最后，这是posts_controller.rb：
class PostsController < ApplicationController
before_action :set_post, only: [:show, :edit, :update, :destroy]
# GET /posts
# GET /posts.json
def index
@posts = Post.all
end
# GET /posts/1
# GET /posts/1.json
def show
end
# GET /posts/new
def new
@post = Post.new
end
# GET /posts/1/edit
def edit
end
# POST /posts
# POST /posts.json
def create
@calendar = Calendar.find(params[:calendar_id])
@post = @calendar.posts.create(post_params)
respond_to do |format|
if @post.save
format.html { redirect_to calendar_path(@calendar), notice: 'Post was successfully created.' }
format.json { render :show, status: :created, location: @post }
else
format.html { render :new }
format.json { render json: @post.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /posts/1
# PATCH/PUT /posts/1.json
def update
respond_to do |format|
if @post.update(post_params)
format.html { redirect_to calendar_path, notice: 'Post was successfully updated.' }
format.json { render :show, status: :ok, location: @post }
else
format.html { render :edit }
format.json { render json: @post.errors, status: :unprocessable_entity }
end
end
end
# DELETE /posts/1
# DELETE /posts/1.json
def destroy
@calendar = Calendar.find(params[:calendar_id])
@post.destroy
respond_to do |format|
format.html { redirect_to calendar_path(@calendar), notice: 'Post was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_post
@post = Post.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def post_params
params.require(:post).permit(:date, :time, :subject, :format, :copy, :media)
end
end
我一直遇到类似的错误。
问题＃1 ：当我尝试从show.html.erb日历视图中删除帖子时：
<h2><%= @calendar.name %> Calendar</h2>
<h3>Posts</h3>
<% if @calendar.posts.any? %>
<table>
<tr>
<th>Date</th>
<th>Time</th>
<th>Subject</th>
<th>Format</th>
<th>Copy</th>
<th>Media</th>
</tr>
<% @calendar.posts.each do |post| %>
<tr>
<td><%= post.date %></td>
<td><%= post.time %></td>
<td><%= post.subject %></td>
<td><%= post.format %></td>
<td><%= post.copy %></td>
<td><%= post.media %></td>
<td><%= link_to 'View', post %></td>
<td><%= link_to 'Update', edit_post_path(post) %></td>
<td><%= link_to 'Delete', post, method: :delete, data: { confirm: 'Are you sure?' } %></td>
</tr>
</table>
<% end %>
...
我得到了：
ActiveRecord::RecordNotFound in PostsController#destroy
Couldn't find Calendar with 'id'=
问题＃2 ：当我尝试从edit.html.erb帖子视图更新帖子时：
<h1>Editing Post</h1>
<%= render 'form' %>
<%= link_to 'Show', @post %> |
<%= link_to 'Back', posts_path %>
我得到了：
ActiveRecord::RecordNotFound in PostsController#update
Couldn't find Calendar with 'id'=
问题＃3 ：当我尝试从show.html.erb帖子视图返回show.html.erb日历视图时：< / em>的
<div>
<p>Date</p>
<%= @post.date %>
</div>
<div>
<p>Time</p>
<%= @post.time %>
</div>
<div>
<p>Subject</p>
<%= @post.subject %>
</div>
<div>
<p>Format</p>
<%= @post.format %>
</div>
<div>
<p>Copy</p>
<%= @post.copy %>
</div>
<div>
<p>Media</p>
<%= @post.media %>
</div>
<%= link_to 'Edit', edit_post_path(@post) %> |
<%= link_to 'Back', posts_path %>
我得到了：
ActiveRecord::RecordNotFound in PostsController#show
Couldn't find Calendar with 'id'=
如果我对错误的解释是正确的，那么问题似乎是我无法检索id calendar所属的post。
换句话说，我无法从子（post）控制器中检索父（日历）id。
我认为这是与我的嵌套浅层资源以及我在视图中构建链接的方式相关的问题。
我无法弄清楚如何使这些链接有效。
如果您可以为我提供解决方案 - 最重要的是推理 - 对于上述三种情况之一，我绝对能够为其他两种情况提出解决方案。
有什么想法吗？
答案 0 :(得分：3)
我找到了解决我的三个问题的每个问题。
问题＃1 ：我换了：
format.html { redirect_to calendar_path(@calendar), notice: 'Post was successfully destroyed.' }
with：
format.html { redirect_to calendar_path(@post.calendar_id), notice: 'Post was successfully destroyed.' }
posts_controller.rb中的。
问题＃2 ：我换了：
<%= link_to 'Back', posts_path %>
使用：
<%= link_to 'Back', calendar_path(@post.calendar_id) %>
在edit.html.erb帖子视图中。
问题＃3 ：我换了：
<%= link_to 'Back', posts_path %>
使用：
calendar_path(@post.calendar_id)
在show.html.erb帖子视图