I have data coming into NiFi in JSON format. Below is the sample

我有JSON格式的数据进入NiFi。以下是样品

{
  "company_name": "mycompany",
  "companytyp": "producer",
  "Welcomemes": "welcome_message1",
  "logo": "//somepath/to/logo URL "
}

I have been trying to apply a JOLT transformation for the following condition:

我一直在尝试对以下情况应用Jolt变换：

• If the length of logo field is more than 10 characters then replace it with blank value


• If the length of logo field is less than or equal to 10 characters then keep the provided value

I have not been able to achieve this. Would really appreciate some help & guidance. I am open to using any other processor too but the preference will be JOLT transformation

我还没能做到这一点。我会非常感谢你的帮助和指导。我也对使用任何其他处理器持开放态度，但首选是Jolt变换

Input 1:

输入1：

{
  "company_name": "mycompany",
  "companytyp": "producer",
  "Welcomemes": "welcome_message1",
  "logo": "This logo value is more than 10 characters "
}

Expected Output 1

预期产出%1

{
  "company_name": "mycompany",
  "companytyp": "producer",
  "Welcomemes": "welcome_message1",
  "logo": ""
}

Input 2:

输入2：

  "company_name": "mycompany",
  "companytyp": "producer",
  "Welcomemes": "welcome_message1",
  "logo": "short logo"
}

Expected Output 2

预期产出2

{
  "company_name": "mycompany",
  "companytyp": "producer",
  "Welcomemes": "welcome_message1",
  "logo": "short logo"
}

I couldn't figure out how to put in an empty string but this spec will replace those logo fields with a single space:

我想不出如何将一个空字符串放入其中，但此规范将用一个空格替换这些徽标字段：

[
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "logo": "=substring(@(1,logo),0,11)",
      "logo_size": "=size(@(1,logo))"
    }
  },
  {
    "operation": "shift",
    "spec": {
      "logo_size": {
        "11": {
          "# ": "logo"
        },
        "*": {
          "@(2,logo)": "logo"
        }
      },
      "logo": null,
      "*": "&"
    }
  }
]

This is the final spec based on solution provided by @mattyb

这是基于@MattyB提供的解决方案的最终规范

 [
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "logo": "=substring(@(1,logo),0,11)",
      "logo_size": "=size(@(1,logo))"
    }
  },
  {
    "operation": "shift",
    "spec": {
      "logo_size": {
        "11": {
          "# ": "logo"
        },
        "*": {
          "@(2,logo)": "logo"
        }
      },
      "logo": null,
      "*": "&"
    }
  },
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "logo": "=trim"
    }
  }]

The trim function trims in an case even if the length of the logo's value is less than 11. For example : "logo":" abc " will be converted eventually to "logo":"abc"

TRIM函数在大小写情况下进行裁剪，即使徽标值的长度小于11。例如：“LOGO”：“ABC”最终将转换为“LOGO”：“ABC”

You can try to convert the related value to null for the cases with the length more than 10, presuming that you have quoted values for the attribute logo for each case.

您可以尝试将长度大于10的案例的相关值转换为NULL，假设您已经为每个案例引用了属性徽标的值。

So, you might consider using the following one :

因此，您可以考虑使用以下方法：

[
  { // prepare the criteria of the string length comparison to be used within the the next spec
    "operation": "modify-overwrite-beta",
    "spec": { 
      "logo_size": "=size(@(1,logo))",
      "x": "=intSum(-10,@(1,logo_size))",
      "xAbs": "=abs(@(1,x))",
      "sz": ["=divide(@(1,x),@(1,xAbs))", -1.0]
    }
  },
  {
    "operation": "shift",
    "spec": {
      "*om*": "&",
      "sz": {
        "*": {
          "@": "logo"
        },
        "-1.0": { // the negative approach is used to determine the cases in which the related length exceeds ten
          "@2,logo": "logo"
        }
      }
    }
  },
  { // convert the values to blanks for the null-valued logo attributes
    "operation": "modify-overwrite-beta",
    "spec": {
      "logo": ["=notNull", ""]
    }
  }
]