Json Jolt to Remove All Nulls from Json

[#1]

Hi,

I have the following Json. I would like to create a Jolt Spec to remove all nulls from all levels. How can I do that? Any help would be appreciated. Thanks

{
"ID": "c22b657e-227b-4c65-e6f8-08d88a3e1118",
"Name": "SomeName",
"TaggedItemName": "SomeValue",
"ITRName": "SomeValue",
"TestReference": null,
"JobCardName": null,
"Comments": "test",
"PrimaryHandoverName": null,
"SecondaryHandoverNumber": null,
"CertificationGroupingName": null,
"DocumentCode": "SomeValue",
"AssignedToName": "SomeName",
"DocumentReference": null,
"TagITRCompletionStatusName": "Rejected",
"ScheduleRevision": null,
"Completed": {
"SignOff_AuthP": "John",
"SignOff_Date": null
},
"Accepted": {
"SignOff_AuthP": "Smith",
"SignOff_Date": null
},
"Approved": {
"SignOff_AuthP": "Ali",
"SignOff_Date": null
},
"ScheduleGroup": null,
"DownloadUri": "SomeUrl",
"UpdatedDate": "2022-01-18T11:36:33.9057626Z",
"CreatedDate": "2020-11-30T10:57:20.8534287Z"
}

[#2]

I don't know if it's possible to do this generically and recursively using Jolt.

Nevertheless, if your schema is well know you can achieve want you want with something like this:

{
  "Completed": {
    "*": {
      "*": {
        "@1": "&3.&2"
      }
    }
  },
  "Accepted": {
    "*": {
      "*": {
        "@1": "&3.&2"
      }
    }
  },
  "Approved": {
    "*": {
      "*": {
        "@1": "&3.&2"
      }
    }
  },
  "*": {
    "*": {
      "@1": "&2"
    }
  }
}

Cheers,

Andre

[#3]

Thank you so much,

That did the trick. You seem to be a json jolt guru. Im trying to understand it myself but its not that straight forward. Can you just elaborate this syntax for me which remove null values on the base level:

"*": {
    "*": {
      "@1": "&2"
    }
 }

Why there is two asterisks in front of it?