add unitstatus

with some TODOs

hosts/hel1-a/configuration.nix

@@ -101,6 +101,13 @@ in {
           };
         };
       };
+
+      unitstatus = {
+        enable = true;
+        email = "motiejus+alerts@jakstys.lt";
+        # see TODO in base/unitstatus/default.nix
+        #units = ["zfs-scrub"];
+      };
     };
   };
 
@@ -587,36 +594,6 @@ in {
         };
       };
 
-      # https://northernlightlabs.se/2014-07-05/systemd-status-mail-on-unit-failure.html
-      "unit-status-mail@" = let
-        script = pkgs.writeShellScript "unit-status-mail" ''
-          set -e
-          MAILTO="motiejus+alerts@jakstys.lt"
-          UNIT=$1
-          EXTRA=""
-          for e in "''${@:2}"; do
-            EXTRA+="$e"$'\n'
-          done
-          UNITSTATUS=$(${pkgs.systemd}/bin/systemctl status "$UNIT")
-          ${pkgs.postfix}/bin/sendmail $MAILTO <<EOF
-          Subject:Status mail for unit: $UNIT
-
-          Status report for unit: $UNIT
-          $EXTRA
-
-          $UNITSTATUS
-          EOF
-
-          echo -e "Status mail sent to: $MAILTO for unit: $UNIT"
-        '';
-      in {
-        description = "Send an email on unit failure";
-        serviceConfig = {
-          Type = "simple";
-          ExecStart = ''${script} "%I" "Hostname: %H" "Machine ID: %m" "Boot ID: %b" '';
-        };
-      };
-
       zfs-scrub.unitConfig.OnFailure = "unit-status-mail@zfs-scrub.service";
       nixos-upgrade.unitConfig.OnFailure = "unit-status-mail@nixos-upgrade.service";
     }