通过 Rails 的关系集合按 has_many 中的用户对帖子进行分组 5

Question

我正在尝试在集合中显示用户（设计）（has_many 通过）。

    <%= @collection.posts.count %> designs by
    <% @collection.posts.each do |post| %>
      <%= link_to image_tag(post.designer.avatar.url.to_s, class: "avatar-small"), post.designer %>
    <% end %>

但它显示重复

我需要按 designer.id 分组。所以我添加了 @collection_designers 行，但我无法按设计师 ID 分组。‍♂️

class CollectionsController < ApplicationController

  def show
    @collection = Collection.find(params[:id])

    #I need to group for designer.id I guess but I could not manage it
    @collection_designers = Collection.find(params[:id]).groups(designers.id) 
  end

  ...

---

关系：

models/collection.rb

class Collection < ApplicationRecord
  belongs_to :designer
  has_many :collectivizations
  has_many :posts, through: :collectivizations
end

models/collectivization.rb

class Collectivization < ApplicationRecord
    belongs_to :post
    belongs_to :collection
end

models/post.rb

class Post < ApplicationRecord
  belongs_to :category
  belongs_to :designer
  has_many :collectivizations
  has_many :collections, through: :collectivizations

Answer 1

首先需要找到uniq设计师id

designer_ids = @collection.posts.distinct.pluck(:designer_id)

然后通过这些id找到设计师

@designers = Designer.where(id: designer_ids)