如何使用 JMESPATH 合并 JSON?

How to merge JSON using JMESPATH?

所以问题是我 JSON 看起来有点像这样:

{
"country": "USA",
"states": [
    {
        "stateName": "California",
        "timeZone": "UTC-8",
        "cities": [
            {
                "cityName": "Los Angeles"
            },
            {
                "cityName": "San Diego"
            }
        ]
    },
    {
        "stateName": "Texas",
        "timeZone": "UTC-8",
        "cities": [
            {
                "cityName": "Houston"
            },
            {
                "cityName": "Dallas"
            }
        ]
    }
]

}

(那个json只是一个例子,不要当真)

我需要做的是列出所有城市,同时从父项中获取 "stateName" 字段并以某种方式将其放入城市对象中,结果如下所示:

[
{
    "stateName": "California",
    "cityName": "Los Angeles"
},
{
    "stateName": "Texas",
    "cityName": "Houston"
},
{
    "stateName": "Texas",
    "cityName": "Dallas"
},
{
    "stateName": "California",
    "cityName": "San Diego"
}

]

我尝试以几种不同的方式使用内置的合并功能,但没有得到任何结果,此外关于该功能的文档不是很直观。

我的一次失败尝试:

merge(`states[].cities[]`, `states[].{stateName: stateName}`)

有什么想法吗?

提前致谢。

您不能使用 jmespath 执行此操作。检查一下:https://github.com/jmespath/jmespath.js/issues/22#issuecomment-394157797

不过,您现在可以这样做:

states[].{stateName: stateName, cities: cities[].cityName}[]

得到如下输出:

[
  {
    "stateName": "California",
    "cities": [
      "Los Angeles",
      "San Diego"
    ]
  },
  {
    "stateName": "Texas",
    "cities": [
      "Houston",
      "Dallas"
    ]
  }
]

我找到了解决方案,但您需要在此处输入一些 hard-coded 值作为查询:

states[].{stateName: stateName, cities: cities[]}[] | @[*].{stateName: {stateName: stateName}, cities: cities} | @[*].[merge(stateName,cities[0]),merge(stateName,cities[1])][]

它给出:

[
  {
    "stateName": "California",
    "cityName": "Los Angeles"
  },
  {
    "stateName": "California",
    "cityName": "San Diego"
  },
  {
    "stateName": "Texas",
    "cityName": "Houston"
  },
  {
    "stateName": "Texas",
    "cityName": "Dallas"
  }
]