如何向多个数组添加元素

Question

我对这样的json文件有一个问题：

{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16132421/",
  "id": "16132421",
  "gender": "W"
}
{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16104273/",
  "id": "16104273",
  "gender": "W"
}
{}
{
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}

我有三个数组。我想将最后一个数组复制到每个prevoius数组中，因此它将如下所示：

{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16104259/",
  "id": "16104259",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}
{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16132421/",
  "id": "16132421",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}

我试图添加或乘以数组，但它不起作用。

当我添加特定的键( {name, url, id, gender} + {brand, cats} )时，它会显示键的位置，但是它将值设置为null。

你能帮我找到解决办法吗？

Answer 1

通过使用-n和[inputs]，或者通过使用-s，将流转换为数组，然后将last项添加到除最后一个.[:-1][]之外的所有。若要筛选空对象，请将其与select进行比较或检查其length。

jq -n '[inputs] | (.[:-1][] | select(. != {})) + last'

演示

jq -s '(.[:-1][] | select(length > 0)) + last'

演示

输出：

{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16132421/",
  "id": "16132421",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}
{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16104273/",
  "id": "16104273",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}

Answer 2

如果流不适合您的内存，则必须使用--stream选项将输入分解为可管理的部分。但是，通过流处理，您不能同时轻松地访问不同的部分。因此，您需要一次传递来检索最后一项，另一次则将其添加到其他项。因为在处理过程中，没有指示项是最后一个项，所以您可以过滤掉那些与所添加的项完全匹配的项(这也很方便地过滤掉以前的空项)。

jq --argfile last <(jq 'reduce inputs as $in (.; $in)' big.json) --stream \
  -n 'fromstream(inputs) + $last | select(. != $last)' big.json

{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16132421/",
  "id": "16132421",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}
{
  "name": "The 24H Automatic Eye Pencil",
  "url": "/3ina/the-24h-automatic-pencil-waterproof-brow-pencil/p-16104273/",
  "id": "16104273",
  "gender": "W",
  "brand": "3INA",
  "cats": [
    "Makeup",
    "Eyebrows",
    "Eyebrow Makeup"
  ]
}