Is an entity body allowed for an HTTP DELETE request?

Question

When issuing an HTTP DELETE request, the request URI should completely identify the resource to delete. However, is it allowable to add extra meta-data as part of the entity

Answer 1

This is not defined.

A payload within a DELETE request message has no defined semantics; sending a payload body on a DELETE request might cause some existing implementations to reject the request.
https://tools.ietf.org/html/rfc7231#page-29