Re: [Qemu-devel] [Nbd] [PATCH] Further tidy-up on block status

[Alex Bligh <alex@alex.org.uk>]

> On 14 Dec 2016, at 18:13, Wouter Verhelst <w@uter.be> wrote:
> 
> Instead, I would suggest that the spec leave it up to the namespace spec
> to define what gets listed when. The namespace should still give some
> indication that a particular *type* of context is available, though;
> e.g., _LIST_ could return 'backup:snapshot-diff{*}' as well as a list of
> 'backup:snapshot{snapshot-X}' contexts, where the latter are all
> available snapshots, and the 'snapshot-diff' bit implies that the whole
> cartesian product of all possible diffs between snapshots is possible in
> a format of 'backup:snapshot-diff{snapshot-X:snapshot-Y}', or some such
> (you get the idea).
> 
> The spec currently says that a server SHOULD allow choosing exports by
> simply naming them, but doesn't make that a MUST; and it also says that
> the query format is defined by the namespace. If we simply clarify that
> the output of _LIST_ doesn't necessarily need to be a full list of all
> that's available (that it may be symbolic in the case of namespaces that
> allow things to be dynamically defined), we should be good.

Let me have a go at a change.

However, note that Vladimir was answering a slightly different question.
I was asking about listing ALL contexts (previously an empty query
string, now a zero length list of queries), not a 'backup:*' type
thing.

-- 
Alex Bligh