server-configs/shared/applications/state/postgresql.nix

{ config, ... }:

let
  stateDir= config.mine.zfsMounts."rpool/safe/svcs/postgresql";
  backupDir = config.mine.zfsMounts."rpool/backup/postgresql";

  postgresql_user = config.systemd.services.postgresql.serviceConfig.User;
  postgresql_group = config.systemd.services.postgresql.serviceConfig.Group;
in {
  services.postgresql.dataDir = stateDir;

  # backup postgresql databases (everything in ensuredatabases)
  services.postgresqlBackup.location = backupDir;

  # ensure correct permissions for postgresql and postgresql backup
  systemd.tmpfiles.rules = [
    "Z ${stateDir} 0700 ${postgresql_user} ${postgresql_group} -"
    "Z ${backupDir} 0700 ${postgresql_user} ${postgresql_group} -"
  ];
}