如何将新字段添加到现有 json答案

【问题标题】：How to add new fields to existing json如何将新字段添加到现有 json
【发布时间】：2020-01-14 02:53:11
【问题描述】：

我有这样的输出 json

[

"city": [
    {
      "street": "street"
      "zip": "223344"
    }
  ]
    "document": [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "12345678",
      "file_name": "test.xml"
    }
  ]
]

我想在“文档”中添加新字段，这样新的输出就会像这样

[

"city": [
    {
      "street": "street"
      "zip": "223344"
    }
  ]
    "document": [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "12345678",
      "file_name": "test.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "123456789",
      "file_name": "test2.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "1234567800",
      "file_name": "test3.xml"
    }
  ]
]

如何添加新字段？我尝试在后面的代码的帮助下做到这一点，但不幸的是我没有得到正确的结果

payload map(value) -> value ++
document: vars.documentsInfo map {
    date: $.createdAt,
    id: $.id,
    file_name: $.name
  }

【问题讨论】：

您使用的是哪个版本的 dataweave？
您的 JSON 无效。另外，我们不知道 vars.documentsInfo 是什么。
vars.documentsInfo 它是数组，我有我之前指出的字段的值，json 这是我描述的结构的唯一示例，我想在其中添加此信息

标签： dataweave mulesoft

【解决方案1】：

如果您使用的是 dw 2.0 和 mule runtime 4.2.2（或更高版本），您可以使用 update 功能。

输入

[
  {
    "city": [
      {
        "street": "street",
        "zip": "223344"
      }
    ]
  },
  {
    "document": [
      {
        "date": "2020-01-10T04:04:01-08:00",
        "id": "12345678",
        "file_name": "test.xml"
      }
    ]
  }
]

数据编织脚本

%dw 2.0
import * from dw::util::Values
output application/json
var data = [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "123456789",
      "file_name": "test2.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "1234567800",
      "file_name": "test3.xml"
    }
]
---
payload update "document" with flatten(payload.document + data)

输出

[
  {
    "city": [
      {
        "street": "street",
        "zip": "223344"
      }
    ]
  },
  {
    "document": [
      {
        "date": "2020-01-10T04:04:01-08:00",
        "id": "12345678",
        "file_name": "test.xml"
      },
      {
        "date": "2020-01-10T04:04:01-08:00",
        "id": "123456789",
        "file_name": "test2.xml"
      },
      {
        "date": "2020-01-10T04:04:01-08:00",
        "id": "1234567800",
        "file_name": "test3.xml"
      }
    ]
  }
]

【讨论】：

【解决方案2】：

输入负载：

{
  "city": [
    {
      "street": "street",
      "zip": "223344"
    }
  ],
  "document": [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "12345678",
      "file_name": "test.xml"
    }
  ]
}

一个名为“documentsInfo”的流变量：

[
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "123456789",
      "file_name": "test2.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "1234567800",
      "file_name": "test3.xml"
    }
]

数据编织：

%dw 2.0
output application/json
---
{
    city: payload.city,
    documents: payload.document ++ vars.documentsInfo
}

产生输出：

{
  "city": [
    {
      "street": "street",
      "zip": "223344"
    }
  ],
  "documents": [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "12345678",
      "file_name": "test.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "123456789",
      "file_name": "test2.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "1234567800",
      "file_name": "test3.xml"
    }
  ]
}

【讨论】：

【解决方案3】：

不幸的是，对于 dataweave，目前没有“更新”数组、字段或对象的好方法。因此解决方法是保存初始值，将其与要添加到文档数组的新对象组合，删除初始信息并重新添加组合值。我在这里使用 dw2.0 中的do 这样做了，希望对您有所帮助：

%dw 2.0
output application/json
var obj = {
  "city": [
    {
      "street": "street",
      "zip": "223344"
    }
  ],
  "document": [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "12345678",
      "file_name": "test.xml"
    }
  ]
}

var documents = [
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "123456789",
      "file_name": "test2.xml"
    },
    {
      "date": "2020-01-10T04:04:01-08:00",
      "id": "1234567800",
      "file_name": "test3.xml"
    }
]


---
do {
    var originalDoc = obj.document
    var newDocumentsArray = documents ++ originalDoc
    ---
    (obj - "document") ++ {documents: newDocumentsArray}
}

【讨论】：