替换列表中的值

Question

我有以下对象：

{
    "db_credentials": {
        "database": "greengrass",
        "host": "localhost",
        "password": "yZqXJzXHLUsLlPm",
        "port": 7086,
        "username": "greengrass"
    },
    "default_interval": 90000,
    "fields_selected": [
        {
            "measurement": "ABPLCGD-GD_AB1AirFlowCalc",
            "aggregation": "last",
            "step": "10m",
            "timeserie_physical": "null",
            "timeserie_type": "null",
            "timeserie_interpolation": "null",
            "timeserie_unit": "null",
            "timeserie_step": "10"
        },
        {
            "measurement": "ABPLCGD-GD_AB1InletAirTempAct",
            "aggregation": "last",
            "step": "10m",
            "timeserie_physical": "null",
            "timeserie_type": "null",
            "timeserie_interpolation": "null",
            "timeserie_unit": "null",
            "timeserie_step": "10"
        }
    ]
}

我想把它变成：

{
  "db_credentials": {
    "database": "greengrass",
    "host": "localhost",
    "password": "yZqXJzXHLUsLlPm",
    "port": 7086,
    "username": "greengrass"
  },
  "default_interval": 90000,
  "fields_selected": [
      {
        "name": "ABPLCGD-GD_AB1AirFlowCalc",
        "aggregation": {
          "step": "10m",
          "function": "last"
        }
      },
      {
        "name": "ABPLCGD-GD_AB1InletAirTempAct",
        "aggregation": {
          "step": "10m",
          "function": "last"
        }
      }
    ]
}

我尝试了多种解决方案，但这是我能得到的最大值：

 jq  ' .fields_selected = .fields_selected | map({name : .measurement , aggregation : {step: .step , function: .aggregation}})' config-it-client.json

但我总是遇到这个错误 无法用字符串“测量”索引数字，我无法弄清楚我做错了什么

Answer 1

我会使用以下内容：

.fields_selected[] |= { name: .measurement, aggregation: { function: .aggregation, step } }

---

要让它工作，你只是缺少括号。

.fields_selected = .fields_selected | ...

意思

( .fields_selected = .fields_selected ) | ...

应该是

.fields_selected = ( .fields_selected | ... )

这给了我们

.fields_selected = (
   .fields_selected |
   map({
      name: .measurement,
      aggregation: {
         function: .aggregation,
         step: .step
      }
   })
)

Demo on jqplay

---

但我们可以改进这一点。 foo = ( foo | ... )一般可以写成foo |= ( ... )。

.fields_selected |= map({
   name: .measurement,
   aggregation: {
      function: .aggregation,
      step: .step
   }
})

我们可以修改 fields 数组中的对象而不是数组本身。

.fields_selected[] |= {
   name: .measurement,
   aggregation: {
      function: .aggregation,
      step: .step
   }
}

最后，{ foo: .foo, ... } 可以缩短为{ foo, ... }。

.fields_selected[] |= {
   name: .measurement,
   aggregation: {
      function: .aggregation,
      step
   }
}

作为一个简单的单行：

jq '.fields_selected[] |= { name: .measurement, aggregation: { function: .aggregation, step } }'

Demo on jqplay

Answer 2

我能够弄清楚我做错了什么：

jq  '.fields_selected = (.fields_selected | map({name : .measurement , aggregation : {step: .step , function: .aggregation}}))' config-it-client.json