On Thu, 25 Mar 2010 08:55:42 -0500 Anthony Liguori <anthony@xxxxxxxxxxxxx> wrote: > On 03/25/2010 08:23 AM, Luiz Capitulino wrote: > > On Wed, 24 Mar 2010 16:40:18 -0500 > > Anthony Liguori<anthony@xxxxxxxxxxxxx> wrote: > > > > > >>>> We need to have a common management interface for third party tools. > >>>> > >>>> > >>> QMP? :-) > >>> > >> Only if QMP is compatible with libvirt. I don't want a user to have to > >> choose between QMP and libvirt. > >> > > Why not? If all they want is a simple qemu session, they can use > > QMP directly, on the other hand if what they want is more complex, > > what's the problem of using a management API like libivrt? > > > > My point is that libvirt should not be a separate management API but > effectively an add-on API that provides higher level features, better > integration with Linux host services, etc. Okay, I fully agree here. > >>> If so, what C clients you expected beyond libvirt? > >>> > >> Users want a C API. I don't agree that libvirt is the only C interface > >> consumer out there. > >> > > Actually, I do agree. Maybe, we don't have other C consumers because they > > weren't crazy enough to parse the crap of the user Monitor (or they do, > > but for simple things). > > > > One possible future client is perf, for example. > > > > Here is my solution (actually it's not mine, you have suggested > > it some time ago): let's provide a convenient way for C clients to > > use QMP. That is, let's have an overly simple library which takes > > QDitcs, sends them to qemu through QMP and returns others QDicts. > > > > Something like the _sketch_ below: > > > > // Open a connection > > int qmp_open(..., QDict **greeting); > > > > // Register a callback for async messages, BUT note that the async message > > // object is passed verbatim > > void qmp_async_mes_handler(..., void (*async_mes_handler)(QDict *mes)); > > > > // Send a QMP command > > int qmp_send(..., const char *command, QDict *params, QDict **res); > > > > Yes, this is the core API. It's missing a mechanism to create a > QMPContext. I'll also argue that we want a set of auto generated > wrappers like: Having the wrappers is one of the points we disagree, but as we have agreed on starting with the core only, I don't see why keep arguing here. If, in the near feature, the need of having wrappers become evident I'll be all for it (this statement is a bit dangerous though, as this need can be subjective). [...] > > but the two main ideas are: > > > > 1. We don't do management > > > > I really believe we need to stop thinking this way. I'm not saying that > qemu-devel is the place where we design virt-manager, but we ought to > consider the whole stack as part of "we". Depends, if you mean that we should be involved with libvirt development, than I completely agree. On the other hand, if you mean than qemu should provide its own management API, than I tend to disagree. And I think this is a very important point of the whole discussion, if you think this way I guess we should start a new thread to collect feedback, listing pros and cons. > >> I really think what we want is for a libvirt user to be able to call > >> libqemu functions directly. There shouldn't have to be libvirt specific > >> functions for every operation we expose. > >> > > Not sure if this is too crazy but, considering this user wants to > > use qemu features not implemented by libvirt yet, what about using both > > libqmp (above) and libvirt at the same time? > > > > Yes, that's *exactly* what I want. Except I want to call it libqemu > because qmp is an implementation detail. libqemu is fine. -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list