Re: [BuildStream] CAS server resource names & instance names

[Jürg Billeter <j bitron ch>]

On Mon, 2018-12-10 at 12:38 +0000, Jim MacArthur wrote:
> No, I think that's a fine way to do it. We'll state that 
> bst-artifact-server does not take an instance name. That precludes it 
> being used as a remote execution store, but I don't think that was ever 
> very valuable outside our testing setup.

As the remote execution API doesn't require instance name support on
the server side, I don't see how this renders bst-artifact-server
unusable for remote execution. That said, it's correct that bst-
artifact-server was never planned to play a significant role in remote
execution. BuildGrid's CAS implementation is expected to be a better
fit for this.

> Remote execution storage will take an optional instance name and not 
> provide it or the initial slash if it's not provided, although I will 
> allow specification of "" as a valid instance name, distinct from not 
> specifying one.

I don't understand this. In the protocol there is no difference between
an empty instance name and not specifying an instance name (as in
protobuf it's the same). Why (and how) would we treat these two cases
differently in BuildStream, possibly violating the spec?

Cheers,
Jürg