Logstask nested field problem

Logs message :
"message" => "Backoff FixedBackOff{interval=0, currentAttempts=10, maxAttempts=9} exhausted "

I need field like below:
"FixedBackOff" => {
"interval"=0,
"currentAttempts"=10,
"maxAttempts"=9
}

Thanks all

I would do that using dissect and kv filters. Something like this.

Thanks working better.