使用 Circe 将字段添加到 json [英] Adding field to a json using Circe

问题描述

我正在阅读 circe 文档，但不知道如何处理以下问题.

I am going trough the circe documentation and can't figure out how to handle the following.

我只想在主 JSON 对象中添加一个带有对象的字段.

I would simply like to add a field with an object in said the main JSON object.

{
  Fieldalreadythere: {}
  "Newfield" : {}
}

我只想在对象中添加Newfield.为了提供一些上下文，我正在处理 Json-ld.我只想添加一个上下文对象.@语境: {}请参见下面的示例:

I just want to add the Newfield in the object. To give a bit of context I am dealing with Json-ld. I just want to add a context object. @context: {} See example below:

{
  "@context": {
    "@version": 1.1,
    "xsd": "http://www.w3.org/2001/XMLSchema#",
    "foaf": "http://xmlns.com/foaf/0.1/",
    "foaf:homepage": { "@type": "@id" },
    "picture": { "@id": "foaf:depiction", "@type": "@id" }
  },
  "@id": "http://me.markus-lanthaler.com/",
  "@type": "foaf:Person",
  "foaf:name": "Markus Lanthaler",
  "foaf:homepage": "http://www.markus-lanthaler.com/",
  "picture": "http://twitter.com/account/profile_image/markuslanthaler"
}

我想添加上下文对象，仅此而已.

I would like to add the context object, that's all.

我怎么能用circe做到这一点.官方文档中的例子主要是讲修改值，但没有实际添加字段等.

How can I do that with circe. The example in the official documentation mostly talk about modifying the value, but nothing to actually add field and so on.

推荐答案

看一看 JsonObject.有 :+ 方法可以满足您的需求.

Take a look at JsonObject. There is :+ method that does what you want.

这是一个简单的例子:

import io.circe.generic.auto._
import io.circe.parser
import io.circe.syntax._

object CirceAddFieldExample extends App {
    val jsonStr = """{
       Fieldalreadythere: {}
    }"""
    val json = parser.parse(jsonStr)
    val jsonObj = json match {
       case Right(value) => value.asObject
       case Left(error) => throw error
    }
    val jsonWithContextField = jsonObj.map(_.+:("@context", contextObj.asJson))
}

这篇关于使用 Circe 将字段添加到 json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！