Hello, I’m trying to make an impermanence setup easier to maintain but keep getting infinite recursion errors. Here’s a brief sketch of what I’m trying to do:
For systemd services, I’m adding a boolean option of whether state should be persisted,
options.systemd.services = lib.mkOption {
type = lib.types.attrsOf (lib.types.submodule {
options.persist = {
enable = lib.mkEnableOption "persist service state";
};
});
};
config.tailscaled.persist.enable = true;
and then for each service I want to persist, I’m bind mounting the systemd StateDirectory to somewhere persistent.
config.fileSystems =
let
persistentServices = lib.filterAttrs (name: service: service.persist.enable) config.systemd.services;
mkBindMountNameValuePair = stateDir: {
name = "/var/lib/${stateDir}";
value = {
device = "/persist/var/lib/${stateDir}";
options = [ "bind" "x-gvfs-hide" ];
};
};
in
lib.listToAttrs (lib.mapAttrsToList (name: service: mkBindMountNameValuePair service.serviceConfig.StateDirectory) persistentServices);
The trouble is this doesn’t work and I get an infinite recursion encounted error. This seems unsuprising because I am reading from config.systemd.services to create the bind mounts, and then presumably NixOS is creating some systemd services/units to actually mount the bind mounts. But I would think that because I am filtering services using my persist.enable option which defaults to false, the configuration should converge to a fixed point and build okay. But this doesn’t happen. Any hints of what I can do to fix this?