[BuildStream] Disruptive Change: Removing docker source from bst-plugins-experimental

[Chandan Singh <chandan chandansingh net>]

Hi,

Docker source plugin (targeting BuildStream 2.0) is currently duplicated in two
repositories - bst-plugins-container [0] and bst-plugins-experimental [1]. I
don't think there is value in keeping them duplicated, so one of them
should be removed.

Since the copy in bst-plugins-container is better tested and more up to date, I
propose to keep that, and remove it from bst-plugins-experimental. This will
also be in line with our decision to have domain-specific plugin repositories.

This will be a breaking change for anyone currently using the Docker source from
bst-plugins-experimental. However, bst-plugins-container should be a drop-in
replacement in almost all cases. It is available on PyPI so can be used as a
`pip` type as well.

For anyone using BuildStream from before the YAML new world order, you can use
the 0.1.2 release. For people using newer BuildStream, use 0.2.0 or later
versions.

If you notice any issues with this version of the plugin, please
report issues on
the GitLab repository.

It is also worth noting that bst-plugins-container is still under development
and hasn't had its 1.0 release yet, so we reserve the right to make breaking
changes until then. Although none are planned at this time. Such a release will
certainly not be feasible before BuildStream 2.0 comes out.

---

The topic of duplication of Docker source was brought up in a recent thread [2].
I am posting this on the list since there was another recent post about
announcing disruptive changes on the list [3].

If people are in agreement with the idea, I will be happy to make this change.

Cheers!
Chandan


[0]: https://gitlab.com/BuildStream/bst-plugins-container
[1]: https://gitlab.com/BuildStream/bst-plugins-experimental
[2]: https://mail.gnome.org/archives/buildstream-list/2019-August/msg00020.html
[3]: https://mail.gnome.org/archives/buildstream-list/2019-August/msg00019.html