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@dergutemoritz according to, Transfer-Encoding isn't required for HEAD requests, and I suspect undertow will strip it out if you set it manually, since there is no body


@bostonaholic If you need access to the request map, you'll need to use immutant.web.async/as-channel from a ring handler instead of wrap-websocket (that's what wrap-websocket is doing for you under the hood


and I would think that wss would just work if you have ssl set up


@tcrawley Indeed - however, Immutant adds a Content-Length: 0 header otherwise which contradicts this paragraph in > A server MAY send a Content-Length header field in a response to a HEAD request (Section 4.3.2 of [RFC7231]); a server MUST NOT send Content-Length in such a response unless its field-value equals the decimal number of octets that would have been sent in the payload body of a response if the same request had used the GET method.


(my actual payload is > 0 bytes long, of course)


I can see if that's Immutant or undertow doing that underneath


In my case, I can't predict the payload size so I'd like to leave it off entirely


That'd be nice!


thanks @tcrawley I’ll take a look at using as-channel