curl --request POST \
  --url https://your-sift-api-url.com/api/v1/user-defined-functions:validate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "expression": "<string>",
  "functionInputs": [
    {
      "identifier": "<string>",
      "dataType": "FUNCTION_DATA_TYPE_UNSPECIFIED",
      "constant": true
    }
  ]
}'

{
  "error": {
    "errorMessage": "<string>"
  },
  "success": {
    "userDefinedFunction": {
      "userDefinedFunctionId": "<string>",
      "name": "<string>",
      "archivedDate": "2023-11-07T05:31:56Z",
      "userDefinedFunctionVersionId": "<string>",
      "version": 123,
      "description": "<string>",
      "changeMessage": "<string>",
      "userNotes": "<string>",
      "expression": "<string>",
      "functionInputs": [
        {
          "identifier": "<string>",
          "dataType": "FUNCTION_DATA_TYPE_UNSPECIFIED",
          "constant": true
        }
      ],
      "functionOutputType": "FUNCTION_DATA_TYPE_UNSPECIFIED",
      "functionDependencies": [
        {
          "userDefinedFunctionVersionId": "<string>"
        }
      ],
      "createdDate": "2023-11-07T05:31:56Z",
      "modifiedDate": "2023-11-07T05:31:56Z",
      "createdByUserId": "<string>",
      "modifiedByUserId": "<string>",
      "metadata": [
        {
          "key": {
            "name": "<string>",
            "type": "METADATA_KEY_TYPE_UNSPECIFIED",
            "archivedDate": "2023-11-07T05:31:56Z"
          },
          "stringValue": "<string>",
          "numberValue": 123,
          "booleanValue": true,
          "archivedDate": "2023-11-07T05:31:56Z"
        }
      ]
    }
  }
}