Convert Text in JSON

Hi All,
this is our stdout {} of Logstash:
{ "_index": "logstash","_type": "_doc","_id": "UPUcBnEBHL50VNrwHY-Q","_version": 1, "_score": null,"_source": {"host": {"name": "xxxxxx"},"@timestamp": "2020-03-23T06:37:16.915Z","data": {"node": "node1","level": "INFO", "timestamp": "2020-03-23T07:37:11,050","thread": "EthScheduler-Workers-3","throwable": "","class": "BlockPropagationManager","message": "Imported #979 / 0 tx / 0 om / 0 (0.0%) gas /(0xcbd404f6cec12eaecb9bed309b953fe5671ee868843807321772369b47756371) in 0.000s."}}

We desire in ELS the "message" text field in "data" object :
"message": "Imported #979 / 0 tx / 0 om / 0 (0.0%) gas / (0xcbd404f6cec12eaecb9bed309b953fe5671ee868843807321772369b47756371) in 0.000s."

in the JSON structured from below:
{Imported: 979,Tx: 0,Gas: 0 Hash:0xcbd404f6cec12eaecb9bed309b953fe5671ee868843807321772369b47756371,duration: 0,000s}

Could you help us solve the problem?
Thanks in advance
BR

If that is your [message] field then either a dissect or a grok filter should be able to extract the fields you want.