Re: 204 no content response with Content-Length header.

Hi Adrien,

On Thu, May 28, 2015 at 11:48:03AM +0000, Adrien de Croy wrote:
> Hi everyone.
> I'm seeing some responses coming back from a server with status code 204 
> and a non-zero Content-Length header.
> Since the spec says that 204 responses MUST not contain a body, and 
> therefore are terminated by the first empty line, what should one make 
> of the Content-Length header?
> Should we (in a proxy)
> a) ignore it and pass it to client
> b) strip it from message to client
> c) treat it as some meta data being communicated / updated
> d) something else

In haproxy, we process them exactly like 304 which are defined pretty
similarly, in that we ignore the content-length since the message doesn't
contain one. This is the behaviour defined in 7230#3.3.3 :

   1.  Any response to a HEAD request and any response with a 1xx
       (Informational), 204 (No Content), or 304 (Not Modified) status
       code is always terminated by the first empty line after the
       header fields, regardless of the header fields present in the
       message, and thus cannot contain a message body.

Please note the "regardless of the header fields present in the message",
this is the key here.

Best regards,

Received on Thursday, 28 May 2015 11:58:40 UTC