[PATCH] Set up Alembic for database migrations

[Lukas Fleischer]

On Wed, 26 Feb 2020 at 22:10:09, Frédéric Mangano-Tarumi wrote:
> Lukas Fleischer [2020-02-26 14:00:51 +0100]
> > We should also think about phasing out the text files in the upgrading/
> > subdirectory. Maybe we should simply keep them for one or two releases
> > and remove the directory entirely later? If anybody ever still needs
> > them after they have been removed, they can still be recovered from the
> > Git history...
> 
> I don\u2019t know who reads the upgrading instructions, but how about having
> a 4.x.0-and-later.txt saying that SQL migrations are now handled by
> Alembic, and referring to migrations/README?
> 
> Let\u2019s also keep in mind that some upgrades might require manual
> intervention anyway. In my opinion these breaking changes should be
> documented in commit messages and synthesized in release notes, but
> whatever the AUR team is used to should be fine too.

I like that suggestion.

In the past, we did not have any release notes, except for announcement
emails sent to the mailing lists. I am not sure how easy it would be to
collect those emails, compile a CHANGES.md file and add it to the source
tree, alongside with upgrade instructions extracted from the upgrading/
subdirectory. This would allow us to get rid of the directory entirely.