- From: Amos Jeffries <squid3@treenet.co.nz>
- Date: Tue, 19 Aug 2014 17:37:33 +1200
- To: ietf-http-wg@w3.org
On 18/08/2014 8:39 p.m., Martijn Faassen wrote: > Hi there, > > No answer to my question at all so far? Perhaps it's the wrong list? > Any feedback would be appreciated! There is no longer an implicit list of hop-by-hop headers. If you are sending any header your proxy needs to comply with the sender criteria for that header. The headers pointed out by RFC2616 are all defined with a MUST on being added to Connection: header explicitly, or were actually having hopX-to-hopY behaviour where X and Y may have any number of intermediary hops between them. You are free to code a default list from the header definitions in your application. But its just a convenience to fix incorrect input (missing Connection: entries). Amos > > Thank you! > > Martijn > > > On Mon, Aug 11, 2014 at 4:42 PM, Martijn Faassen <faassen@startifact.com> wrote: >> Hi there, >> >> [I hope this question reaches the right mailing list] >> >> I'm trying to find the equivalent of RFC 2616, section 13.5.1 in the >> new specs. This section defines those header fields considered >> hop-by-hop, i.e.: >> >> - Connection >> - Keep-Alive >> - Proxy-Authenticate >> - Proxy-Authorization >> - TE >> - Trailers >> - Transfer-Encoding >> - Upgrade >> >> I need such a list in order to implement a Python WSGI-based proxy. >> See PEP 3333: >> >> http://legacy.python.org/dev/peps/pep-3333/#other-http-features >> >> However, because WSGI servers and applications do not communicate >> via HTTP, what >> RFC 2616 calls "hop-by-hop" headers do not apply to WSGI internal >> communications. >> WSGI applications must not generate any "hop-by-hop" headers [4], >> attempt to use >> HTTP features that would require them to generate such headers, or >> rely on the content >> of any incoming "hop-by-hop" headers in the environ dictionary. WSGI >> servers must >> handle any supported inbound "hop-by-hop" headers on their own, such >> as by decoding >> any inbound Transfer-Encoding, including chunked encoding if applicable. >> >> So, a WSGI proxy has to remove any hop-by-hop headers from the >> response of the host it is proxying, and not pass them along. WSGI has >> its own iterator based mechanism to support chunking, and a WSGI >> server can then add the appropriate headers. >> >> In section 13.5.1 of RFC 2616 these hop-by-hop headers are specified, >> but I can't find the equivalent in the newer RFCs. >> >> I do find section 6.1 in rfc7230, so I think this means that a >> conforming server would list related headers in the Connection. But >> what about Transfer-Encoding, for instance? A server that sends >> "Connection: close" may not send Transfer-Encoding? >> >> It's certainly possible that I'm missing something. I haven't read the >> complete specs yet. But any guidance would be appreciated. >> >> Regards, >> >> Martijn >
Received on Tuesday, 19 August 2014 05:38:16 UTC