On Fri, Jul 27, 2012 at 06:20:48PM +0800, Wenchao Xia wrote: > This patch would add option -j in qemu-img info command, which > would generate json output in stdout.
I like this idea in general, because currently apps (oVirt, OpenStack, etc) rely on parsing the human format, which is just as evil as libvirt relying on -help format. It would be helpful if you actually included the JSON output in your commit message. For the benefit of other reviews, it generates the following: #qemu-img info -j /var/lib/libvirt/images/bar.qcow2 { "information": { "actual_size": "139264", "fmt": "qcow2", "virtual_size": "10485760", "filename": "/var/lib/libvirt/images/bar.qcow2", "cluster_size": 65536, "encrypted": 0, "snapshot_list": [ ], "dirty_flag": 0, "backing_filename": "/dev/sda1" }, "return": 0 } IIUC,the 'return' element here is just duplicating the qemu-img exit status. I think this is rather dubious, and would rather just see the stuff in the 'information' sub-block be output directly. It also seems to forget to mention the backing file format. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|