How to alter the requested payload to create the entities.

The consumer has the different payload structure which they are posting on endpoint for e.g "api/node/article" but drupal doesn't supports that structure as it only accepts the below structure:

{
"data": {
"type": "node--article",
"attributes": {
"title": "My custom title",
"body": {
"value": "Custom value",
"format": "plain_text"
}
}
}
}

Does anybody know how to normalize the posted request & create the entities based on that? any help would be appreciated.

Thanks, Dinesh