Re: [Qemu-devel] [PATCH COLO-Frame v8 19/34] qmp event: Add event notification for COLO error

[zhanghailiang]

On 2015/8/31 23:07, Eric Blake wrote:
> On 08/31/2015 03:27 AM, zhanghailiang wrote:
>
> > > > +Data: None.
> > > > +
> > > > + - "mode": COLO mode, 'primary' or 'secondary'
> > > > + - "error": Error message (json-string, optional)
>
> The "Data: None" designation is inconsistent with the fact that you do
> provide data.

Will fix in next version.

> > > > +
> > > > +Example:
> > > > +
> > > > +{"timestamp": {"seconds": 2032141960, "microseconds": 417172},
> > > > + "event": "COLO_EXIT", "data": {"mode": "primary"}}
> > >
> > > It might also be useful to provide a machine-parseable parameter on
> > > whether the exit was due to an internal error vs. an external request.
> > > Maybe by adding 'flag':'bool', since presence or absence of 'error' is
> > > not as nice.
> >
> > Good idea, but i think the type of 'flag' changes to 'str' maybe better,
> > which can be 'error' or
> > 'request', 'bool' is not so self-explanatory.
> > The original reason for adding 'error' member is to help
> > users to know what exactly happen, but it seems to be difficult to
> > exactly class all errors,
> > so i will remove it.
>
> Keeping an optional 'error' for human consumption is not bad; it's just
> that it is also nice to provide something for machine consumption (and
> we typically document that machines should NOT parse 'error' messages).

OK, then i will keep it, and manage all the error places and error messages 
carefully.

Thanks,
zhanghailiang