the version on the tip handles now identity and q-values. The logic sketched below does not handle cases, where e.g. identiy or * is higher than gzip qvalue, or explicit forbidding of gzip. The values are doubles, so one has to be careful with comparisons. I am not sure about the logic for http/1.1, if we really should assume gzip by default.
-gustaf On 27.10.12 15:03, Stephen Deasey wrote: > On Sat, Oct 27, 2012 at 1:13 PM, Gustaf Neumann <neum...@wu.ac.at> wrote: >> On 26.10.12 15:47, Stephen Deasey wrote: >>> I think the spec says that for HTTP/1.1, if the client doesn't >>> explicitly say to NOT send the body gzipped, say by using a q value of >>> 0 (which we don't actually check for, woops...), then the server can >>> choose the encoding, although it should prefer the identity, unless >>> that's unavailable. So we're being very pushy... >> now we do check for the qvalues used in connection with >> gzip. So, a client can now specify explicitly, that gzip is >> NOT wanted via "gzip; q=0". What the code still does not do >> is comparing the identity-qvalue with the gzip-qvalue or >> combination with wildcards "....*;q=..." > Jeff had a go at this as well: > > https://bitbucket.org/jeffr/naviserver-queues/changesets > > Here's the feedback I tacked on to the end of a mercurial question via email: > > > > It bothers me a bit that a fresh Ns_Set has to be allocated, and also > the parsing code is pretty gnarly and hard to verify. It looks about > right, but I'd have to resort to pencil and paper to be more sure, and > the fact I haven't done that reminds me that people tend to not look > too closely at these things and that's where bugs can fester. I wonder > if there's another way of doing this... > > You'll have to double check the details, but IIRC q values go from > 0-999. If 'gzip' is present without a q value then it's as if it had > q=1 -- that's the default. If it's not present, it's as if it were but > with q=0. So, how about a function like Ns_HeaderQ(header, attr) which > returns the integer q value for the specified atttribute. It simply > uses strstr to find gzip. If it doesn't, return 0. If it does, then > check for a q=. If it's the character '0', return 0. If there's no q, > return 1. If it's something else, parse the int and return that. Then > you can use it something like: > > > if (!(connPtr->flags & NS_CONN_SENTHDRS) > && !(connPtr->flags & NS_CONN_SKIPBODY)) { > > contentEncoding = Ns_SetIGet(Ns_ConnHeaders(conn), "Accept-Encoding"); > > if (Ns_HeaderQ(contentEncoding, "gzip") > 0 || > Ns_HeaderQ(contentEncoding, "*") > 0) { > gzip = 1; > > > I'm not sure how eager the server should be sending gzipped content. > An alternative to the above would be to keep the existing eager use of > gzip, but respect the client's negative assertion: > > > if (!(connPtr->flags & NS_CONN_SENTHDRS) > && !(connPtr->flags & NS_CONN_SKIPBODY)) { > > contentEncoding = Ns_SetIGet(Ns_ConnHeaders(conn), "Accept-Encoding"); > > if (connPtr->request->version >= 1.1) { > if ((!Ns_HeaderQ(contentEncoding, "gzip", &q) || q > 0) > && (!Ns_HeaderQ(contentEncoding, "*", &q) || q > 0)) { > gzip = 1; > } > } else if ((Ns_HeaderQ(contentEncoding, "gzip", &q) && q > 0) > || (Ns_HeaderQ(contentEncoding, "*", &q) && q > 0)) { > gzip = 1; > } > > > Here Ns_HeaderQ is modified to return NS_TRUE or NS_FALSE depending on > whether the attribute is present, and the q value is returned into the > given variable. HTTP 1.0 clients have to explicitly ask for gzip, 1.1 > clients get it unless the say they don't want it. > > ------------------------------------------------------------------------------ > WINDOWS 8 is here. > Millions of people. Your app in 30 days. > Visit The Windows 8 Center at Sourceforge for all your go to resources. > http://windows8center.sourceforge.net/ > join-generation-app-and-make-money-coding-fast/ > _______________________________________________ > naviserver-devel mailing list > naviserver-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/naviserver-devel ------------------------------------------------------------------------------ WINDOWS 8 is here. Millions of people. Your app in 30 days. Visit The Windows 8 Center at Sourceforge for all your go to resources. http://windows8center.sourceforge.net/ join-generation-app-and-make-money-coding-fast/ _______________________________________________ naviserver-devel mailing list naviserver-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/naviserver-devel
