无法使用 Ancestry gem（ruby on rails）为嵌套评论分配父 ID

Question

我正在创建嵌套评论（就像你在 Reddit 上看到的那样）。我能够创建父评论，但是当我尝试创建子评论时，它只是呈现为父评论。

在我的 rails 控制台中，"ancestry" 字段返回 "nil"。

这是我的评论管理员：

class CommentsController < ApplicationController
  before_action :set_comment, only: [:show, :edit, :update, :destroy]
  before_filter :authenticate_user!

  def show
    @comment = Comment.find(params[:id])
  end

  def new
    @link = Link.find(params[:link_id])
    @comment = Comment.new(:parent_id => params[:parent_id])
    @comments = Comment.all
  end

  def create
    @link = Link.find(params[:link_id])

    @parent = Link.find(params[:link_id]) if params[:link_id]
    @parent = Comment.find(params[:comment_id]) if params[:comment_id]

    @comment = @parent.comments.new(comment_params)
    @comment.user = current_user

    respond_to do |format|
      if @comment.save
        format.html { redirect_to @link, notice: 'Comment was successfully created.' }
        format.json { render json: @comment, status: :created, location: @comment }
      else
        format.html { render action: "new" }
        format.json { render json: @comment.errors, status: :unprocessable_entity }
      end
    end
  end

  def destroy
    @comment.destroy
    respond_to do |format|
      format.html { redirect_to :back, notice: 'Comment was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private

    def set_comment
      @comment = Comment.find(params[:id])
    end


    def comment_params
      params.require(:comment).permit(:link_id, :body, :user_id)
    end
end

这是我的_comment_form部分

<%= div_for(comment) do %>
    <div class="comments_wrapper clearfix">
        <div class="pull-left">
            <p class="lead"><%= comment.body %></p>
            <p><small>Submitted <strong><%= time_ago_in_words(comment.created_at) %> ago</strong> by <%= comment.user.email %></small></p>
                    <div id="reply" style="display:none;">
                <%= form_for [@comment = Comment.new(:parent_id => params[:parent_id])] do |f| %>
                <%= f.hidden_field :parent_id %>
                  <%= f.text_area :body %> <br>
                  <%= f.submit %>
                  <% end %>
                </div>
        </div>

        <div class="actions btn-group pull-right">
            <button onClick="$('#reply').show()" class="btn btn-sm btn-default">Reply</button>

            <% if comment.user == current_user -%>
                <%= link_to 'Destroy', comment, method: :delete, data: { confirm: 'Are you sure?' }, class: "btn btn-sm btn-default" %>
            <% end %>
        </div>
    </div>

<% end %>

这些是我的路线

Rails.application.routes.draw do
  resources :comments
  devise_for :users
  devise_for :installs
  resources :links do
    member do 
      put "like", to: "links#upvote"
      put "dislike", to: "links#downvote"
    end
    resources :comments
  end

  root to: "links#index"
end

Answer 1

以前遇到过这个问题；答案在这里：

Ancestry gem in Rails and Mutli Nesting

ancestry (this is why we changed back to acts_as_tree) 的问题是您必须 在 ancestry 列中定义所有祖先 （与 相对）只是 acts_as_tree 的 parent_id 列。

因此，当您调用 object 的 .children 时（您实际上只是用 top-level parent 填充 ancestry）是children 的 that parent 的列表（没有其他）。

您需要的是引用整个祖先系。这非常棘手，但可以使用以下代码实现：

#app/views/links/index.html.erb
<%= render @link.comments if @post.comments.any? %>

#app/views/links/_comment.html.erb
<%= comment.title %>
<%= render "form", locals: {link: @link} %>
<%= render comment.children if comment.has_children? # > adds recursion (multi level nesting) %>

#app/views/links/_form.html.erb
<%= form_for link.comments.new do |c| %>
   <%= c.text_field :body %>
   <%= c.submit %>
<% end %>

控制器如下：

#app/controllers/comments_controller.rb
class CommentsController < ApplicationController
   def create
      @link = Link.find params[:link_id]
      @comment = @link.comments.new ancesrtry: parent(params[:parent_id])
   end

   private

   def parent(param)
       parents = Comment.find(param).pluck(:parent)
       "#{parents}/#{param}" #-> ruby automatically returns last line
   end
end

这应该为您设置正确的路径，部分应该为您提供多层嵌套所需的适当递归。

无法使用 Ancestry gem（ruby on rails）为嵌套评论分配父 ID

Unable to assign a parent id to nested comments, using Ancestry gem (ruby on rails)

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