From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49018) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YnYIM-0004Z3-ER for qemu-devel@nongnu.org; Wed, 29 Apr 2015 16:09:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YnYIJ-0006KR-7v for qemu-devel@nongnu.org; Wed, 29 Apr 2015 16:09:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49186) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YnYII-0006K9-W1 for qemu-devel@nongnu.org; Wed, 29 Apr 2015 16:09:19 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t3TK9Gne028433 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Wed, 29 Apr 2015 16:09:17 -0400 Message-ID: <55413A6B.4050005@redhat.com> Date: Wed, 29 Apr 2015 16:09:15 -0400 From: John Snow MIME-Version: 1.0 References: <1430334844-7015-1-git-send-email-jsnow@redhat.com> <1430334844-7015-3-git-send-email-jsnow@redhat.com> <55413026.7010604@redhat.com> In-Reply-To: <55413026.7010604@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v4 2/4] scripts: qmp-shell: Expand support for QMP expressions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake , qemu-devel@nongnu.org Cc: kchamart@redhat.com On 04/29/2015 03:25 PM, Eric Blake wrote: > On 04/29/2015 01:14 PM, John Snow wrote: >> This includes support for [] expressions, single-quotes in >> QMP expressions (which is not strictly a part of JSON), and >> the ability to use "True", "False" and "None" literals instead >> of JSON's equivalent true, false, and null literals. >> >> qmp-shell currently allows you to describe values as >> JSON expressions: >> key={"key":{"key2":"val"}} >> >> But it does not currently support arrays, which are needed >> for serializing and deserializing transactions: >> key=[{"type":"drive-backup","data":{...}}] >> >> qmp-shell also only currently accepts doubly quoted strings >> as-per JSON spec, but QMP allows single quotes. >> >> Lastly, python allows you to utilize "True" or "False" as >> boolean literals, but JSON expects "true" or "false". Expand >> qmp-shell to allow the user to type either, converting to the >> correct type. >> >> As a consequence of the above, the key=val parsing is also improved >> to give better error messages if a key=val token is not provided. >> >> CAVEAT: The parser is still extremely rudimentary and does not >> expect to find spaces in {} nor [] expressions. This patch does >> not improve this functionality. >> >> Signed-off-by: John Snow >> --- >> scripts/qmp/qmp-shell | 63 ++++++++++++++++++++++++++++++++++++++------------- >> 1 file changed, 47 insertions(+), 16 deletions(-) >> > >> >> +class FuzzyJSON(ast.NodeTransformer): >> + '''This extension of ast.NodeTransformer filters literal "true/false/null" >> + values in an AST and replaces them by proper "True/False/None" values that >> + Python can properly evaluate.''' >> + def visit_Name(self, node): >> + if node.id == 'true': >> + node.id = 'True' >> + if node.id == 'false': >> + node.id = 'False' >> + if node.id == 'null': >> + node.id = 'None' >> + return node > > Cute! > ;) > Reviewed-by: Eric Blake > So the only remaining crime I am aware of is that when specifying key=val pairs without hoping for a favorable QMP deserialization is that we still accept e.g. "TrUe" and "FaLSe" and so on. Patch 4 tries to make amends by explicitly converting objects back to strict JSON and printing that out for the user (if they supplied -v) so we can observe what conversions qmp-shell made for us to make things nice. And I think I'm done playing with this for now. If I go any further, there's bound to be flex and bison files in the tree! --js