Hi! Marius Bakke <mar...@gnu.org> skribis:
> There is a patch to update MariaDB here: > > https://issues.guix.gnu.org/43355 > > Users of mysql-service-type will need to run 'mysql_upgrade' afterwards. > > I have been considering adding an AUTO-UPGRADE? parameter of > mysql-service-type that runs 'mysql_upgrade' as part of the activation > script. > > Another approach is adding a 'herd upgrade' Shepherd action along with a > news entry describing what to do. Of course it is possible to do both, > having 'auto-upgrade?' _and_ a Shepherd action for manual upgrades. Running upgrades in the activation snippet sounds reasonable. If ‘mysql_upgrade’ detects what version it is upgrading from, that’s perfect. However, the activation snippet runs upon reconfigure even if the service is not restarted; so you could find yourself running version N but you’ve just upgraded the database to N+1. The safest way would be to do that in the ‘start’ method. But you can also add an ‘upgrade’ action to the service, just like ‘mcron’ has a ‘schedule’ action. > While that works for MariaDB, I'm not sure what to do about Postgres. > For those unfamiliar, the procedure for upgrading from PostgreSQL 10 > (current default) to 11 (available in Guix) is roughly: > > sudo cp -a /var/lib/postgresql/data /var/lib/postgresql/data10 > sudo -u postgres $(guix build postgresql)/bin/pg_upgrade \ > --old-bindir=$(guix build postgresql@10)/bin \ > --new-bindir=$(guix build postgresql)/bin \ > --old-datadir=/var/lib/postgresql/data10 \ > --new-datadir=/var/lib/postgresql/data > > In order to automate it, we need to somehow preserve the "previous" > version of PostgreSQL so that we can reach it when the major version > changes. Or add an 'upgrade-from' parameter to > postgresql-service-type. One way would be to determine the previous generation number of /run/current-system and use, say, /var/guix/profiles/system-42-link/bin as the bindir. Not pretty. A nicer way would be to add a ‘bindir’ and a ‘datadir’ action to the postgresql service; the activation snippet could use it to find the right values. Thoughts? Thanks, Ludo’.
