Hi all I realised that I sent this request just the Friday before the HK summit, a really bad timing :( Resending, anyone is available to have a look at this thread? Please note that the code change has a -1 and I am not submitting a new patch as we (the reviewer and myself) are stuck in finding a common solution for the original bug. As soon as we have a consensus I'll be really happy to submit a new patch.
Regards -- Andrea Rosa >-----Original Message----- >From: Rosa, Andrea (HP Cloud Services) >Sent: 01 November 2013 14:35 >To: OpenStack Development Mailing List (openstack-dev@lists.openstack.org) >Subject: [openstack-dev] Nova XML serialization bug 1223358 moving >discussion here to get more people involved > >Hi all > >Long story short: a long time ago I raised a bug [1] and I started to work on >the >fix: GuoHui LIu (the reviewer) and myself had long and useful discussion >about the right solution for that but now we are stuck and we need some >more opinions to find a proper one. > >And now the long story: >When we have an instance booted from a volume and we don't specify the >image details in the boot command the XML serialization of instance details >fails and the API call (like nova show) returns a 500 error. >The problem is that the image properties is mandatory to serialize but the xml >serializer can't manage properly an empty value. >In particular in the xmlutil we a have the class Selector which selects datum >within a specific object, that class is designed to deal with missing data in >the >object but not to deal with an empty object. >At this moment to deal with missing data the logic used in the method is to >catch KeyError or IndexError exceptions: >try: > obj = obj[elem] >except (KeyError, IndexError): > if do_raise: > raise KeyError(elem) > >My simple fix was to following the same logic and add a new exception to get >caught TypeError which is raised when the passed object is empty (it is an >empty string). > >One of the main complain was that this approach tends to add some business >logic in the xmlutil and also adding a new exception could hide some potential >errors. >I can't disagree but at the same time I say that I am following the same logic >that we already have there. > >We are now stuck, because the long-term solution probably is to rethink the >XML serialization process to allow more flexibility but that doesn't seem an >easy task and I really want to get this bug fixed. > >What do you think? >Anyone is available to have a look and give us an opinion? > >Please @Llu feel free to add your comments or any missing points. > >PS: I am not an expert of the nova xmlutil, could be that I am missing some >easy points if so, please let me know. > >Thanks >-- >Andrea Rosa > >[1] https://bugs.launchpad.net/nova/+bug/1223358 > > >_______________________________________________ >OpenStack-dev mailing list >OpenStack-dev@lists.openstack.org >http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
