How to filter not null in graphql?

[kokizzu]

I have query something like this:

{
  device_list(status: "Active", role: "Server") {
    name
    interface {
      mac_address // can be null
      ip_addresses {
        id
        address // can be empty array
        custom_fields // can be blank
      }
    }
  }
}

the graphql query itself very slow and returning html error after 5 minutes unless i remove ip_addresses part, how can I filter out/remove unnecessary nested field? eg. remove those without mac_address, remove those without address/custom_fields, etc

currently it returns something like this:

      {
        "id": "79",
        "name": "nls-xxx-xxx-1",
        "interfaces": [
          {
            "mac_address": null,
            "ip_addresses": []
          }, // a lot of these