在 ActiveModelSerializer 中序列化与自定义字段的关系

Question

我在使用 ActiveModelSerializers 正确序列化我的模型时遇到了一些问题。设置如下：

# controllers/posts_controller.rb
class PostsController < ApplicationController

  def index
   render json: @posts, each_serializer: PostSerializer, include: %w(comments), fields: post_fields
  end

  private

  def post_fields
    { posts: [:name, :content, :author] }
  end
end

# serializers/post_serializer.rb
class PostSerializer < ActiveModelSerializer
  attributes :name, :content, :author
  has_many :comments, serializer: CommentSerializer
end

当我向 posts#index 端点发出请求时，我期待 JSON 格式为 JSON-API 规范的响应，例如以下：

{
  "data": {
    "type": "post",
    "id": 1,
    "attributes": {
      "name": "My first post",
      "author": "Mr. Glass",
      "content": "This is my first post ..."
    },
    "relationships": {
      "comments": {
        "data": {
          "id": 1,
          "type": "comments"
        }
      }
    }
  },
  "included": {
    "type": "comments",
    "id": 1,
    "attributes": {
      "content": "First!"
    }
  }
}

然而，实际的响应是这样的：

{
  "data": {
    "type": "post",
    "id": 1,
    "attributes": {
      "name": "My first post",
      "author": "Mr. Glass",
      "content": "This is my first post ..."
    }
  },
  "included": {
    "type": "comments",
    "id": 1,
    "attributes": {
      "content": "First!"
    }
  }
}

而且整个关系块都不见了。有没有办法让实际响应中的关系块再次出现？

Answer 1

我想通了！

对于任何未来的读者 - 如果您想在 ActiveModelSerializers 中使用 relationships 块并使用 fields 选项，您需要执行以下操作：

# in your controller
render json: @posts, include: %(comments), fields: post_fields

def post_fields
  # note the inclusion of "comments" in the array of fields to be 
  # serialized. That is the change you will need to make.
  { posts: [:name, :author, :content, :comments] }
end

希望对您有所帮助！

在 ActiveModelSerializer 中序列化与自定义字段的关系

Serialize relationships with custom fields in ActiveModelSerializer

ruby-on-rails

active-model-serializers

json-api