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

I don't think a good answer to this has been posted, although there's been lots of great comments on existing answers. I'll lift the gist of those comments into a new answer:

This paragraph from RFC7231 has been quoted a few times, which does sum it up.

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.

What I missed from the other answers was the implication. Yes it is allowed to include a body on DELETE requests, but it's semantically meaningless. What this really means is that issuing a DELETE request with a request body is semantically equivalent to not including a request body.

Including a request body should not have any effect on the request, so there is never a point in including it.

tl;dr: Techically a DELETE request with a request body is allowed, but it's never useful to do so.