Re: File search progress: database review and question on triggers

["Ludovic Courtès" <ludo@gnu.org>]

Hi Pierre,

Pierre Neidhardt <mail@ambrevar.xyz> skribis:

> Ludovic Courtès <ludo@gnu.org> writes:

[...]

>> It would be nice to see whether/how this could be integrated with
>> third-party channels.  Of course it’s not a priority, but while
>> designing this feature, we should keep in mind that we might want
>> third-party channel authors to be able to offer such a database for
>> their packages.
>
> Wouldn't it work automatically for any substitute server?

“Something” needs to build the file-to-package database (which is what
you’re working on), and then there needs to be a way for users to fetch
that database.  This is all orthogonal to substitutes, as I see it,
which is why I think we need to think about integrating it maybe with
‘guix publish’ on the server side and (guix channels) on the client
side.

>>> - Find a way to garbage-collect the database(s).  My intuition is that
>>>   we should have 1 database per Guix checkout and when we `guix gc` a
>>>   Guix checkout we collect the corresponding database.
>>
>> If we download a fresh database every time, we might as well simply
>> overwrite the one we have?
>
> But then we would miss the database when switching Guix generation.

Ah got it; having a database known to correspond to a specific commit is
even better.

However, note that it could take time for the server to provide the
complete database for a commit (the time for as many packages as
possible to be built), so clients may want to refresh it anyway, or even
perhaps to use an older database.

Thanks,
Ludo’.