使用 jq/bash 的可变键迭代 JSON 数组的最佳方法

Question

我有一个 JSON 文件，如下所示：

{
    "Results": [
        {
            "Severity": "LOW",
            "InstalledVersion": "1.21.1ubuntu2",
            "FixedVersion": "1.21.1ubuntu2.1"
        },
        {
            "Severity": "LOW",
            "InstalledVersion": "1.21.1ubuntu2"
        },
        {
            "Severity": "HIGH",
            "VulnerabilityID": "CVE-2016-2781"
        }
    ]
}

我想创建以下 JSON-file:

[
    {
        "Severity": "LOW",
        "InstalledVersion": "1.21.1ubuntu2",
        "FixedVersion": "1.21.1ubuntu2.1",
        "VulnerabilityID": ""
    },
    {
        "Severity": "LOW",
        "InstalledVersion": "1.21.1ubuntu2",
        "FixedVersion": "",
        "VulnerabilityID": ""
    },
    {
        "Severity": "HIGH",
        "InstalledVersion": "",
        "FixedVersion": "",
        "VulnerabilityID": "CVE-2016-2781"
    }
]

我尝试遍历第一个 JSON-文件，但是当我按照以下方式这样做时，我遇到随机解析错误（使用我正在处理的真实 JSON-文件).所以我认为我正在做的管道有问题。

jq -c '.Results[]' my.json | while read i; do
    echo $i;
done

在 JSON 文件中，我正在使用 jq -c '.Results[]' 完美运行，但是当我使用 jq 对结果 $i 的操作在迭代时，我突然遇到几个解析错误。

是否有更好的方法来遍历 JSON 文件中的键值对？ Ofcause 我可以只安装 Python/R 并进行典型的练习，但我真的希望它能在 shell 脚本中工作。

Answer 1

您可以使用 + 通过组合字段将两个对象相加；如果两个对象具有相同的对象，则使用右手对象的值。因此，如果您将现有对象设为 RHS:

 jq '[ .Results[] | {Severity:"", InstalledVersion:"", FixedVersion:"", VulnerabilityID:""} + . ]' input.json   
[
  {
    "Severity": "LOW",
    "InstalledVersion": "1.21.1ubuntu2",
    "FixedVersion": "1.21.1ubuntu2.1",
    "VulnerabilityID": ""
  },
  {
    "Severity": "LOW",
    "InstalledVersion": "1.21.1ubuntu2",
    "FixedVersion": "",
    "VulnerabilityID": ""
  },
  {
    "Severity": "HIGH",
    "InstalledVersion": "",
    "FixedVersion": "",
    "VulnerabilityID": "CVE-2016-2781"
  }
]

Answer 2

另一种将回退添加到空字符串的方法：

[ .Results[] | . + { VulnerabilityID: (.VulnerabilityID // ""), FixedVersion: (.FixedVersion // ""), InstalledVersion: (.InstalledVersion // "") } ]

[
  {
    "Severity": "LOW",
    "InstalledVersion": "1.21.1ubuntu2",
    "FixedVersion": "1.21.1ubuntu2.1",
    "VulnerabilityID": ""
  },
  {
    "Severity": "LOW",
    "InstalledVersion": "1.21.1ubuntu2",
    "VulnerabilityID": "",
    "FixedVersion": ""
  },
  {
    "Severity": "HIGH",
    "VulnerabilityID": "CVE-2016-2781",
    "FixedVersion": "",
    "InstalledVersion": ""
  }
]

Online demo

Answer 3

还有一个变化

jq '[
    .Results[]
    | .FixedVersion //= ""
    | .VulnerabilityID //= ""
    | .InstalledVersion //= ""
]' file.json

Answer 4

更通用的方法：

jq '.Results |
    (map(keys)|add|unique|map({key:.,value:""})|from_entries) as $default |
    map($default + .)
   ' input.json

解释：

1) map(keys)|add|unique
   gets all the keys. If it's a subset you are interested, you can substitute it with :
   ["FixedVersion", "VulnerabilityID", "InstalledVersion"]
2) map({key:.,value:""})|from_entries) as $default
   constructs a default object with all (or selected) keys.
3) $default + .
   adds a key from default object if the key does not exist.

使用 jq/bash 的可变键迭代 JSON 数组的最佳方法

Best way to iterate over JSON array with variable keys with jq/bash

arrays

bash

json

jq

Online demo