- From: James M Snell <jasnell@gmail.com>
- Date: Tue, 18 Jun 2013 16:49:32 -0700
- To: Jeff Pinner <jpinner@twitter.com>
- Cc: Amos Jeffries <squid3@treenet.co.nz>, HTTP Working Group <ietf-http-wg@w3.org>
+1 to END_STREAM and END_HEADERS, +1 to reserving 0x2 for END_MESSAGE later on but -1 to including it in this implementation draft. On Tue, Jun 18, 2013 at 11:39 AM, Jeff Pinner <jpinner@twitter.com> wrote: > A suggestion for the HEADERS frame flags that incorporates "FINAL", > "MSG_DONE", and changes the polarity of "CONTINUES:" > > 0x1: END_STREAM - indicates that this frame is the last the endpoint will > send on the identified stream. > 0x2: END_MESSAGE - indicates that this frame comprises a message boundary. > 0x4: END_HEADERS - indicates that this frame marks the end of the encoded > header block. > > For compression, the text can then read something like "a header block is > compressed and encoded according to <link header compression spec> and > serialized in a sequence of HEADERS frames... frames that comprise an > encoded header block must be written sequentially and cannot be interleaved > with other frames... the final frame in the sequence must be identified by > setting the END_HEADERS flag" (re-written by our editors to make it easier > to understand) > > > > On Sat, Jun 15, 2013 at 9:45 PM, Amos Jeffries <squid3@treenet.co.nz> wrote: >> >> From an implementation point of view a default value of 0 for both flags >> is easiest of all to implement, with polarity of 1 being set for the >> exceptional cases. >> >> The bulk of frames in a stream will *not* be the FINAL frame. Likewise the >> bulk of headers delivered will likely be small enough to *not* have a >> CONTINUES necessary. >> >> So to me the existing polarity seems to be correct. I propose renaming the >> CONTINUES flag to "EXTEND" (extended headers present) or "LARGE" (large >> header set) or "MULTI" (multiple header blocks) or something else avoiding >> the unfortunate wording overlap with the FINAL semantics description. >> >> Amos >> >> >> On 16/06/2013 12:49 p.m., Roberto Peon wrote: >>> >>> no objections here with the proposal. >>> >>> >>> On Sat, Jun 15, 2013 at 5:15 PM, James M Snell <jasnell@gmail.com >>> <mailto:jasnell@gmail.com>> wrote: >>> >>> And fwiw, I already had a note for this in my list of todos >>> following the interim. >>> >>> On Jun 15, 2013 5:13 PM, "James M Snell" <jasnell@gmail.com >>> <mailto:jasnell@gmail.com>> wrote: >>> >>> +1... consistency makes the most sense. >>> >>> On Jun 15, 2013 5:06 PM, "William Chan (ιζΊζ)" >>> <willchan@chromium.org <mailto:willchan@chromium.org>> wrote: >>> >>> I don't particularly care. I just want to point out that >>> the reason it "natural" to do it the way it's already >>> done, is FINAL and CONTINUES are the exceptional cases. So >>> to the degree that it's nicer to by default have no flags >>> set, the current approach is better. I don't have any >>> paint to waste on this bike shed though. >>> >>> On Sat, Jun 15, 2013 at 4:57 PM, Mike Belshe >>> <mike@belshe.com <mailto:mike@belshe.com>> wrote: >>> >>> I agree on the consistency issue Dave presents. I >>> also like Dave's suggestion to use 1 to mean final >>> everywhere. >>> >>> Mike >>> >>> process question: is it valuable to reply in github? >>> or is the list preferred? >>> >>> >>> Always the list. If you see much discussion on github, >>> yell at them to bring it to the list. And any >>> commits/issues/updates on github should reference the >>> rough consensus from the mailing list. >>> >>> >>> >>> >>> On Sat, Jun 15, 2013 at 4:14 PM, David Morris >>> <dwm@xpasc.com <mailto:dwm@xpasc.com>> wrote: >>> >>> >>> >>> This issue: >>> >>> https://github.com/http2/http2-spec/issues/129 >>> >>> describes my concern that the polarity is reversed >>> between STREAM FINAL >>> and HEADER CONTINUES which are both flag bits used >>> to manage continuation. >>> >>> I think this will introduce confusion to folks >>> analyzing wire level bits >>> as well as reading code. >>> >>> I do acknowledge the the current flag names match >>> the sense of the >>> polarity so the names probably should change. >>> >>> Dave Morris >>> >>> >>> >>> >> >> >
Received on Tuesday, 18 June 2013 23:50:20 UTC