多态嵌套关联上的 Rails active_model_serializers [英] Rails active_model_serializers on polymorphic nested association

问题描述

在设置 gem 之后，我试图获得一个深层嵌套的多态关联数据.

after setup the gem i've tried to get a deep nested polymorphic associated data.

但 gem 只渲染 1 级关联数据.

but the gem just render the 1 level associated data.

序列化器

class CommentsSerializer < ActiveModel::Serializer
  attributes :id, :title, :body, :user_id, :parent_id, :commentable_id, :commentable_type

  belongs_to :user
  belongs_to :commentable, :polymorphic => true
end

经过一番研究

在 active_model_serializers github 文档页面上

on the active_model_serializers github doc page

我已经尝试过这个解决方案，但也没有奏效

i've tried this solution, and did not worked either

has_many :commentable

def commentable
  commentable = []
  object.commentable.each do |comment|
    commentable << { body: comment.body }
  end
end

请问有人可以就这个问题提供一些提示吗?

please someone can spare a tip on this issue?

对于一些我应该使用的

ActiveModel::Serializer.config.default_includes = '**'

我也试过这个配置

下面的截图说明了这种情况

The screeshot below illustrate this case

这个评论有很多评论的回复，但只渲染一个.我想呈现此评论的其余评论.

this comment has many reply's by commentable, but just render one. i would like to render the rest of comments of this comment.

推荐答案

您需要正确定义序列化程序并注意不要递归渲染所有内容.我已经设置了这两个模型:

You need to properly define your serializers and be careful not to render everything recursively. I have setup these 2 models:

class Post < ApplicationRecord
  has_many :comments, as: :commentable
end

class Comment < ApplicationRecord
  belongs_to :commentable, polymorphic: true
end

还有这些序列化器:

class CommentSerializer < ActiveModel::Serializer
  attributes :id, :body

  belongs_to :commentable, serializer: CommentableSerializer
end

class CommentableSerializer < ActiveModel::Serializer
  attributes :id, :body

  has_many :comments, serializer: ShallowCommentSerializer
end

class ShallowCommentSerializer < ActiveModel::Serializer
  attributes :id, :body
end

您需要另一个序列化程序来处理帖子的所有评论，以便评论不会尝试呈现帖子，而这会尝试呈现评论等...

You need another serializer for all comments of a post, so that the comments don't try to render the post, which would try to render the comments, etc...

保持你的

ActiveModel::Serializer.config.default_includes = '**'

配置选项已打开.

调用 http://localhost:3000/comments/1 产生:

{
  "id": 1,
  "body": "comment",
  "commentable": {
    "id": 1,
    "body": "post",
    "comments": [
      {
        "id": 1,
        "body": "comment"
      },
      {
        "id": 2,
        "body": "Reply comment"
      }
    ]
  }
}

我相信，这就是您想要实现的目标.

which, I believe, is what you were trying to achieve.

这篇关于多态嵌套关联上的 Rails active_model_serializers的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！