From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43158) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cUaLB-0001OW-NO for qemu-devel@nongnu.org; Fri, 20 Jan 2017 09:38:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cUaLA-0000Kx-PP for qemu-devel@nongnu.org; Fri, 20 Jan 2017 09:38:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60746) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cUaLA-0000Jf-Gm for qemu-devel@nongnu.org; Fri, 20 Jan 2017 09:38:56 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8BADFC0567B2 for ; Fri, 20 Jan 2017 14:38:56 +0000 (UTC) References: <20170118161653.19296-1-eblake@redhat.com> <20170118161653.19296-7-eblake@redhat.com> <8737gffkhy.fsf@dusky.pond.sub.org> <87h94u42xf.fsf@dusky.pond.sub.org> From: Eric Blake Message-ID: <8b87e0b6-c928-1dd0-037b-9215d741eb93@redhat.com> Date: Fri, 20 Jan 2017 08:38:49 -0600 MIME-Version: 1.0 In-Reply-To: <87h94u42xf.fsf@dusky.pond.sub.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="a4OpE2oFwEhgPhMwRvFUipCDfvfPLXWL2" Subject: Re: [Qemu-devel] [PATCH v2 6/6] qapi: Promote blockdev-change-medium arguments to QAPI type List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: qemu-devel@nongnu.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --a4OpE2oFwEhgPhMwRvFUipCDfvfPLXWL2 From: Eric Blake To: Markus Armbruster Cc: qemu-devel@nongnu.org Message-ID: <8b87e0b6-c928-1dd0-037b-9215d741eb93@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2 6/6] qapi: Promote blockdev-change-medium arguments to QAPI type References: <20170118161653.19296-1-eblake@redhat.com> <20170118161653.19296-7-eblake@redhat.com> <8737gffkhy.fsf@dusky.pond.sub.org> <87h94u42xf.fsf@dusky.pond.sub.org> In-Reply-To: <87h94u42xf.fsf@dusky.pond.sub.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 01/20/2017 01:15 AM, Markus Armbruster wrote: >>> Isn't Since: 2.5 misleading? The anonymous type goes back to 2.5, bu= t >>> the name doesn't. >> >> It matches what we've done elsewhere - when refactoring .json files to= >> create a new type, but where the new type doesn't represent anything >> different over the wire than what was previously sent, we've documente= d >> the new struct name as of the older release where the wire format was >> introduced. But as long as the command says 'since 2.5', I'm okay if = we >> want to mark the struct as 'since 2.9', if that's easier to think abou= t. >=20 > Sticking to established practice is better than inconsistent practice. >=20 > That said, I wonder why we bother to track "since" for types. "Since" > is important information for external interfaces. Why is it useful for= > purely internal ones? >=20 > External visible are commands, events, and members of types used by > commands or events. I guess what we can do is treat a type-wide 'Since: 2.5' as the default for all its members that don't supply any other '(since 2.6)' note. You're right that types themselves (even when used in a command) are NOT the API, and that we can refactor type names without breaking wire compatibility, but having a default for when each member of the type was first made available makes sense since we DO care when members were introduced. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --a4OpE2oFwEhgPhMwRvFUipCDfvfPLXWL2 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJYgiD5AAoJEKeha0olJ0Nq0hkIAIL3zlPcqUQXMeJk4/9BFKFy FJUAasxu7/ZqtNgBWHYyNaKWnbWovDdHZYsyF1lBLnOFVBVR90fzugN+wQvz7D/W UjIh09nrgCIe/vvJ++zRWNkdE7vzkx1qjrZY4cCyizhAbu8jzqD7Kc869LcPTD69 1ArHtZt7X987nUfcJ/9r9cF2IttLOLwuO+TRubcnzIi/dyLSKt0Hj4oJupxArWtt FilGW/QJQ12r5BA20gn6oWOlaY/DzWXB4t086amh1ZGStsN1apVbxTTPpcwH0A8E uGbBOjBD0kMwBxvOYEot/OVEAZNdTxAEs7QZ/p2hq9eq/FcgtEnQYA4KpkIIeiI= =kwVK -----END PGP SIGNATURE----- --a4OpE2oFwEhgPhMwRvFUipCDfvfPLXWL2--