Re: [Qemu-devel] [v5 12/12] migration: Add commands to set and query parameter

[Li, Liang Z]

> > >> The command takes a list of key-value pairs.  Looks like this
> > >> (example stolen from your patch to qmp-commands.hx):
> > >>
> > >>     { "execute": "migrate-set-parameters",
> > >>       "arguments": { "parameters":
> > >>                      [ { "parameter": "compress-level", "value": 1
> > >> } ] } }
> > >>
> > >> Awkward.  I'd very much prefer
> > >>
> > >>     { "execute": "migrate-set-parameters",
> > >>       "arguments": { "compress-level", 1 } }
> > >>
> > >> I.e. the command simply takes the parameters as optional arguments.
> > >> Simpler, and a natural use of the schema language.
> > >
> > > Yes, it seems complicated.  Eric suggested to use this type of
> > > interface, because it can support different type of parameters if
> > > some new parameters will be added.
> >
> > I don't understand.
> >
> > Schema for the three parameters we have now:
> >
> > { 'command': 'migrate-set-parameters',
> >   'data': { '*compression-level': 'int',
> >             '*compression-threads': 'int,
> >             '*decompression-threads': 'int' } }
> >
> > Let's add a parameter with some other type:
> >
> > { 'command': 'migrate-set-parameters',
> >   'data': { '*compression-level': 'int',
> >             '*compression-threads': 'int,
> >             '*compression-algorithm': 'CompressionAlgorithm',
> >             '*decompression-threads': 'int', } }
> >
> > CompressionAlgorithm could be an enum.
> >
> > Why wouldn't that work?
> 
> To be honest, I know very little about QMP and JSON. What should I do to
> make the schema as you described?
> 

You have answered me, sorry!