使用jq

Question

我想使用jq将数组元素添加到现有的json文件中。

element.json

{
  "category": "fiction",
  "author": "Evelyn Waugh",
  "title": "Sword of Honour",
  "price": 12.99
}

original.json

{
    "store": {
        "book": [
            {
                "category": "reference",
                "author": "Nigel Rees",
                "title": "Sayings of the Century",
                "price": 8.95
            }
        ],
        "bicycle": {
            "color": "red",
            "price": 19.95
        }
    },
    "expensive": 10
}

我尝试关注

jq ".store.book += [input] "  original.json  element.json

以上工作正常，它添加了数组并显示如下所示的输出

{
    "store": {
        "book": [
            {
                "category": "reference",
                "author": "Nigel Rees",
                "title": "Sayings of the Century",
                "price": 8.95
            },
            {
                "category": "fiction",
                "author": "Evelyn Waugh",
                "title": "Sword of Honour",
                "price": 12.99
            }
        ],
        "bicycle": {
            "color": "red",
            "price": 19.95
        }
    },
    "expensive": 10
}

现在有两个问题

• 首先，我尝试将更新的输出保存在以下的original.json中，但它清空了我的两个文件

  jq ".store.book += [input] " original.json element.json > original.json

然后我用过，但未安装海绵，因此无法在生产中安装

jq ".store.book += [input] "  original.json  element.json | sponge original.json

以下内容适用于First

jq ".store.book += [input] "  original.json  element.json > original.tmp && mv original.tmp original.json

• 第二，我希望在添加数组之前更改 price 的值，然后添加 original.json

EDIT1： 根据反馈，我尝试了以下操作，但第二次仍然出错

jq ".store.book += [input.price=2] "  original.json  element.json

它引发错误

jq: error (at element.json:6): Invalid path expression near attempt to access element "price" of {"category":"fiction","aut...

Answer 1

  

第一

[ input|.price |= $newprice ]

  

第二

最简单的方法是将输出写入一个临时文件，然后在检查是否成功之后将其移到适当位置。