Re: [BuildStream] 1.4 release timeline, targets and breaking changes

[Tristan Van Berkom <tristan vanberkom codethink co uk>]

On Wed, 2018-11-14 at 09:01 +0000, Angelos Evripiotis via BuildStream-list wrote:
> Hi!
>
> Just checking we didn’t miss out an exciting breaking change :)
>
> Are we also planning to remove 'bst checkout' in favour of 'bst artifact
> checkout' in 1.4? That would be cool.

That is fine with me, yes it would be better to do all of the breaking
changes we would want in one cycle, hopefully only leaving behind the
plugins separation for 1.6, and then never do it again.

> It sounds like without recursive checkout, it wouldn’t have feature
> parity though (‘--deps run’). Did I understand this correctly?

When running `bst artifact checkout` and providing an element instead
of an artifact name, we would have feature parity.

We would have the additional feature of being able to checkout a single
artifact by its artifact name, also.

As you point out, only `--deps none` can work with artifact names until
 recursive resolution of dependencies via artifact metadata instead of
loaded project state is implemented, so we will need early exits in 1.4
for these cases.

> > * bst artifact subgroup
> >
> > This was discussed at length on the mailing list, and has not come
> > to a conclusion (I am supposed to post a summary to pick this back
> >          up).
> >
> > The thread starts here:
> >
> > https://mail.gnome.org/archives/buildstream-list/2018-July/msg00051.html
> >
> > This is too large of a scope to hope to land in 1.4, however some
> > of the features are easy enough to implement and we expect a
> > minimal implementation of:
> >
> > o bst artifact log (display a build log of an artifact)
> >      o bst artifact checkout
> >
> >      For the checkout command, it cannot be born with a recursive
> >      checkout as this requires reconstruction of the build graph from
> >      artifact metadata, and we agreed this would be out of scope for 1.4.
> >
> >      STATUS: Todo
>
> It was mentioned in the original 'bst artifact *' message:
>
> >   o It would also be interesting to move `checkout`, `push` and `pull`
> >     commands under the new `artifact` group (deprecating the existing
> >     commands).
> https://mail.gnome.org/archives/buildstream-list/2018-July/msg00051.html
>
> We can add it to the breaking changes in 1.4 if so:
> https://gitlab.com/BuildStream/website/issues/24

I agree with this, note that `push` and `pull` also have `--deps`
arguments and will need the same treatment as `checkout` for the same
reasons.

Cheers,
    -Tristan