-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Tres Seaver wrote: > Guido van Rossum wrote: >> On Wed, Oct 8, 2008 at 6:39 PM, Bill Janssen <jans...@parc.com> wrote: >>> Josiah Carlson <josiah.carl...@gmail.com> wrote: >>> >>>> But yes, zope needs to be changed to reflect the updated >>>> asyncore/asynchat semantics. Trust me; it's faster, cleaner, and >>>> easier to use now. >>> Just for completeness, I built a fresh 2.6, installed Medusa (from >>> http://www.amk.ca/python/code/medusa.html), and it runs just fine (well, >>> as well as it does on 2.5, anyway). I think this is a Zope issue. >> Way back in the day, Zope monkeypatched whole parts of asyncore, >> replacing them with some of its own code. If that's still the case, >> this breakage should be no surprise. > > Zope has been hooking the 'asyncore.loop' function (wrapping it in order > to add a "clean shutdown' flog) since 2001 at least (the 2.5 branch is > the earliest checkout I have, and it was branched in early January 2002). > > Zope also began patched asyncore's logging functions in 2.7, and later > updated that patch to make the logger use the stdlib 'logging' module. > > I think the change we need to make (in ZServer/medusa/http_server.py) is > to emulate the new 'writeable' implementation in asynchat, at least when > running under 2.6. > > Zope's 'ZServer.medusa.http_server.http_request.writable()' > implementation is:: > > def writable (self): > # this is just the normal async_chat 'writable', > # here for comparison > return self.ac_out_buffer or len(self.producer_fifo) > > > The Python 2.5 asynchat.asynchat.writable does:: > > def writable (self): > "predicate for inclusion in the writable for select()" > # return len(self.ac_out_buffer) or len(self.producer_fifo) or > # (not self.connected) > # this is about twice as fast, though not as clear. > return not ( > (self.ac_out_buffer == '') and > self.producer_fifo.is_empty() and > self.connected > ) > > The Python 2.6 asynchat.asynchat.writable now does:: > > def writable (self): > "predicate for inclusion in the writable for select()" > return self.producer_fifo or (not self.connected) > > > medusa 0.5.4's medusa.http_server.http_request doesn't override > 'writable', but it does have a broken 'writeable_for_proxy': > > > def writable_for_proxy (self): > # this version of writable supports the idea of a 'stalled' > # producer > # [i.e., it's not ready to produce any output yet] This is > # needed by > # the proxy, which will be waiting for the magic combination of > # 1) hostname resolved > # 2) connection made > # 3) data available. > if self.ac_out_buffer: > return 1 > elif len(self.producer_fifo): > p = self.producer_fifo.first() > if hasattr (p, 'stalled'): > return not p.stalled() > else: > return 1
*crickets*. The 2.6 version of asyncore *also* breaks supervisord, which does *not* use Zope's medusa: it uses medusa 0.5.4. How is anybody supposed to write a package which sits atop a library like asyncore in a fashion portable across Python versions? The changes to the implementation in 2.6 (there is no real API) can't be reconciled, AFAICT. Tres. - -- =================================================================== Tres Seaver +1 540-429-0999 tsea...@palladion.com Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJrZG0+gerLs4ltQ4RAnsmAJ9v/vPkHgE3AdP5ngVuYaKlxDGhJACgsCi2 3awbUffi2BU41qQgd6eJV18= =WBt6 -----END PGP SIGNATURE----- _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
