如何在 ruby​​ on rails 视图中呈现嵌套 json 对象的内容

Question

我正在尝试将数据从 API 响应 (JSON) 呈现到我的视图中。

出于某种原因，我只能访问顶级对象而没有任何问题。 但是在从嵌套对象中检索数据时，我的知识是有限的。

如果有人可以帮助我，将不胜感激。

控制器文件

require 'httparty'

class BlogController < ApplicationController

    include HTTParty

    def show
      id = params[:id]
      get("posts/#{id}")
    end

    def index
      get('posts')
    end

    private

    def get(path)
      @host = 'api.example.com'
      @blog = HTTParty.get('https://' + @host + '/' + path )
      @post = HTTParty.get('https://' + @host + '/' + path )
      
      return false if response.status != 200
      puts response.body
    end
end

视图.html.erb

<p id="notice"><%= notice %></p>

<h2><%= @post["title"] %></h2>
<p><%= @post["description"] %></p>
<p><%= @post["content"] %></p>
<p><%= @post["heroimage.url"] %></p> <# This here is the problem how to render the url object which is part of "heroimage" parent

我正在使用的 JSON 响应：

{
  "id": 1,
  "title": "First Post",
  "description": "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam",
  "content": "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. \n\n![g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg](/uploads/g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg)\n\n\nDuis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi. Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat. ",
  "author": null,
  "created_at": "2021-10-28T21:31:10.445Z",
  "updated_at": "2021-11-10T17:54:36.175Z",
  "heroimage": {
    "id": 1,
    "name": "g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg",
    "alternativeText": "",
    "caption": "",
    "width": 2048,
    "height": 1536,
    "formats": {
      "large": {
        "ext": ".jpg",
        "url": "/uploads/large_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg",
        "hash": "large_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00",
        "mime": "image/jpeg",
        "name": "large_g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg",
        "path": null,
        "size": 184.83,
        "width": 1000,
        "height": 750
      },
      "small": {
        "ext": ".jpg",
        "url": "/uploads/small_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg",
        "hash": "small_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00",
        "mime": "image/jpeg",
        "name": "small_g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg",
        "path": null,
        "size": 50.69,
        "width": 500,
        "height": 375
      },
      "medium": {
        "ext": ".jpg",
        "url": "/uploads/medium_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg",
        "hash": "medium_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00",
        "mime": "image/jpeg",
        "name": "medium_g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg",
        "path": null,
        "size": 110.16,
        "width": 750,
        "height": 563
      },
      "thumbnail": {
        "ext": ".jpg",
        "url": "/uploads/thumbnail_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg",
        "hash": "thumbnail_g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00",
        "mime": "image/jpeg",
        "name": "thumbnail_g-000261-g_W2615899_6-ktm-300-exc-637602315686776824.jpg",
        "path": null,
        "size": 10.56,
        "width": 208,
        "height": 156
      }
    },
    "hash": "g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00",
    "ext": ".jpg",
    "mime": "image/jpeg",
    "size": 711.13,
    "url": "/uploads/g_000261_g_W2615899_6_ktm_300_exc_637602315686776824_a3b44fdf00.jpg",
    "previewUrl": null,
    "provider": "local",
    "provider_metadata": null,
    "created_at": "2021-11-10T16:22:27.152Z",
    "updated_at": "2021-11-10T16:22:27.169Z"
  }
}

如前所述，我正在尝试显示网址（这是“英雄形象”下的一级）。

Answer 1

不应该像

@post[:heroimage][:url]

工作？

使用 ruby​​，您应该能够将键视为符号。 并且 ruby​​ 不会在散列中使用点表示法，因此您需要使用方括号。

Answer 2

您必须将响应从 json 转换为 Hash 并为此使用：

parsed_response = JSON.parse(response.body)

之后它只是一个散列，因此您可以简单地访问如下：

parsed_response['heroimage']['url']

我建议在这里使用dig

parsed_response.dig('heroimage', 'url')

如果你想要一个结构化对象，那么我建议使用RecursiveOpenStruct它将所有字段作为嵌套对象属性

structured = RecursiveOpenStruct.new(parsed_response)
structured.heroimage.url