ActionController::UrlGenerationError in Comments#new

投稿されたコメント（comment）に対して共感（agree）ボタンを押したときエラーが出ました。

（実際の画像　https://gyazo.com/4ed6810b0da66868150129870face223 ）

おそらくcomment_agree_path(comment, @agree) の@agreeに値が入っていないことが問題だと思うのですが、commentsコントローラーのnewアクションで@agree = Agree.find(params[:agree_id])と定義しても変化はありませんでした。何が問題なのでしょうか？

エラーメッセージは以下の通りです。

【エラーメッセージ画面 (Gyazo)】
https://gyazo.com/6a1492037b3cd20561c4c217e30c098a

発生している問題・エラーメッセージ

エラーメッセージ

ActiveRecord::RecordNotFound in CommentsController#new
Couldn't find Agree without an ID

該当のソースコード

Ruby
1【news．html．erb 共感ボタンのあるページ 】
2
3<div class="comment">
4      <div class="comment-box">
5      <%= form_with model: [@comment, @messages],url:message_comments_path(@message),local: true do |f| %>
6        <%= f.text_area :text, placeholder: "質問する", class: "comment-text" %>
7        <%= hidden_field_tag :message_id,@message.id %>
8      <p class="comment-warn">
9        <p>他の生徒の質問で回答できる場合には積極的に回答してください！</p>
10      </p>
11      <br>
12      <%= f.submit "質問する",class: "comment-btn"%>
13     <% end %>
14  </div>
15
16<div class="comment-box2">
17      <h4 class="comment-list">＜質問一覧＞</h4>
18      <% if @comments %>
19        <% @comments.each do |comment| %>
20        <div class="comment-content">
21         <% if current_user.genre == "教員" %> 
22          <p>
23            <strong><%= link_to comment.user.name, "#", class: "comment-nickname" %></strong>
24          </p>
25          <% elsif current_user.genre == "生徒" %>
26          <strong class= "comment-nickname">匿名</strong>
27          <% end %>
28          <p class="comment-texts">
29            <%= comment.text%>
30          </p>
31          <div class="favorite-btn">
32             <% if user_signed_in? && current_user.already_agreed?(comment) %>
33              <%= link_to comment_agree_path(comment, @agree), method: :delete do %>
34              <p class="agree-btn-color">共感</p>
35             <% end %>
36             <% elsif user_signed_in? && current_user.id == comment.user_id%>
37              <p class="agree-btn">共感</p>
38             <% else %>
39            <%= link_to comment_agrees_path(comment), method: :post do %>
40             <p class="agree-btn">共感</p>
41             <% end %>
42             <% end %>
43            <p class="agree-count"><%= @comment.agrees.count%>人</p>
44          </div>
45          <ul class="comment-time">
46            <p class="time"><%= comment.created_at.to_s(:datetime_jp) %></p>
47            <p class="time"><%= comment.created_at.to_s(:datetime_jp2) %></p>
48          </ul>
49           <% if current_user.genre == "教員" %>
50          <p>
51            <%= link_to message_comment_path(@message.id, comment.id), method: :delete, class: "delete-button" do %>
52            <i class="fas fa-trash"></i>
53            <% end %>
54          </p>
55          <% elsif user_signed_in? && current_user.id == comment.user_id %>
56          <p>
57            <%= link_to message_comment_path(@message.id, comment.id), method: :delete, class: "delete-button" do %>
58            <i class="fas fa-trash"></i>
59            <% end %>
60          </p>
61          <% end %>
62          <p>
63          </div>
64        <% end %>
65      <% end %>
66    </div>
67  </div>
68  <p class="back-to-top2"><%=link_to '戻る', root_path %></p>
69

Ruby
1class AgreesController < ApplicationController
2
3    def create
4        @agree = current_user.agrees.create(comment_id: params[:comment_id])
5        redirect_back(fallback_location: root_path)
6      end
7    
8      def destroy
9          @comment = Comment.find(params[:comment_id])
10          @agree = current_user.agrees.find_by(comment_id: @comment.id)
11          @agree.destroy
12          redirect_back(fallback_location: root_path)
13      end
14  
15    private
16  
17      def agree_params
18        params.require(:agree).permit(
19          :comment_id, 
20          :user_id
21        ).merge(user_id: current_user.id, comment_id: params[:comment_id])
22      end
23  
24end
25

Ruby
1class CommentsController < ApplicationController
2    
3  def index    
4    @messages = Message.all
5    @room = Room.all
6    @message = Message.find(params[:id])
7    
8  end
9
10  def new
11    @message = Message.find(params[:message_id])
12    @comments = @message.comments.order("created_at DESC")
13    @comment = Comment.new
14    @messages = Message.all
15    @room = Room.all
16    @agree = Agree.find(params[:id])
17  end
18
19  def create
20     @message = Message.find(params[:message_id])
21     @comment = @message.comments.new(comment_params)
22    if @comment.save
23      redirect_to new_message_comment_path(@message)
24    else
25      redirect_to new_message_comment_path(@message)
26    end
27  end
28
29  def destroy
30    @comment = Comment.find(params[:id])
31    @message = @comment.message
32    if @comment.destroy
33       redirect_to new_message_comment_path(@message)
34    else
35       @comments = @message.comments.order("created_at DESC")
36       render :new
37    end       
38  end
39    
40      private
41      def comment_params
42        params.require(:message).permit(:text).merge(user_id: current_user.id, message_id: params[:message_id])
43      end
44end
45

Ruby
1【routes.rb】
2
3Rails.application.routes.draw do
4  devise_for :users
5  get 'messages/index'
6  get 'comments/index'
7  
8  root to: "rooms#index"
9  resources :users
10  resources :rooms do
11    resources :messages
12  end
13  resources :messages do
14    resources :comments
15end
16
17  resources :comments do
18    resources :agrees, only: [:create, :destroy]
19end
20
21end
22

Ruby
1【agree.rb】
2
3class Agree < ApplicationRecord
4    belongs_to :user
5    belongs_to :comment
6
7    validates_uniqueness_of :comment_id, scope: :user_id
8end

Ruby
1comment_agrees POST     /comments/:comment_id/agrees(.:format)          agrees#create
2comment_agree DELETE    /comments/:comment_id/agrees/:id(.:format)      agrees#destroy

行動規範の内容に同意します

回答1件

自己解決

Ruby
1【new.html.erb（共感ボタンのあるファイル）】
2下記の２行目をbefore→afterに変更したところうまくいきました。
3
4（before）
5<%= link_to comment_agree_path(comment, @agree), method: :delete do %>
6
7(after)
8<%= link_to comment_agree_path(comment, comment.agrees), method: :delete do %>