nixpkgs/nixos/modules/system/boot/systemd-unit-options.nix
aszlig 9d8a8126e9
systemd: Add support for path units.
This allows to define systemd.path(5) units, for example like this:

{
  systemd = let
    description = "Set Key Permissions for xyz.key";
  in {
    paths.set-key-perms = {
      inherit description;
      before = [ "network.target" ];
      wantedBy = [ "multi-user.target" ];
      pathConfig.PathChanged = "/run/keys/xyz.key";
    };

    services.set-key-perms = {
      inherit description;
      serviceConfig.Type = "oneshot";
      script = "chown myspecialkeyuser /run/keys/xyz.key";
    };
  };
}

The example here is actually useful in order to set permissions for the
NixOps keys target to ensure those permisisons aren't reset whenever the
key file is reuploaded.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
2014-03-31 12:33:25 +02:00

410 lines
11 KiB
Nix
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

{ config, pkgs }:
with pkgs.lib;
let
checkService = v:
let assertValueOneOf = name: values: attr:
let val = getAttr name attr;
in optional ( hasAttr name attr && !elem val values) "Systemd service field `${name}' cannot have value `${val}'.";
checkType = assertValueOneOf "Type" ["simple" "forking" "oneshot" "dbus" "notify" "idle"];
checkRestart = assertValueOneOf "Restart" ["no" "on-success" "on-failure" "on-abort" "always"];
errors = concatMap (c: c v) [checkType checkRestart];
in if errors == [] then true
else builtins.trace (concatStringsSep "\n" errors) false;
unitOption = mkOptionType {
name = "systemd option";
merge = loc: defs:
let
defs' = filterOverrides defs;
defs'' = getValues defs';
in
if isList (head defs'')
then concatLists defs''
else mergeOneOption loc defs';
};
in rec {
unitOptions = {
enable = mkOption {
default = true;
type = types.bool;
description = ''
If set to false, this unit will be a symlink to
/dev/null. This is primarily useful to prevent specific
template instances (e.g. <literal>serial-getty@ttyS0</literal>)
from being started.
'';
};
baseUnit = mkOption {
type = types.nullOr types.path;
default = null;
description = "Path to an upstream unit file on which the NixOS unit configuration will be based.";
};
description = mkOption {
default = "";
type = types.str;
description = "Description of this unit used in systemd messages and progress indicators.";
};
requires = mkOption {
default = [];
type = types.listOf types.str;
description = ''
Start the specified units when this unit is started, and stop
this unit when the specified units are stopped or fail.
'';
};
wants = mkOption {
default = [];
type = types.listOf types.str;
description = ''
Start the specified units when this unit is started.
'';
};
after = mkOption {
default = [];
type = types.listOf types.str;
description = ''
If the specified units are started at the same time as
this unit, delay this unit until they have started.
'';
};
before = mkOption {
default = [];
type = types.listOf types.str;
description = ''
If the specified units are started at the same time as
this unit, delay them until this unit has started.
'';
};
bindsTo = mkOption {
default = [];
type = types.listOf types.str;
description = ''
Like requires, but in addition, if the specified units
unexpectedly disappear, this unit will be stopped as well.
'';
};
partOf = mkOption {
default = [];
type = types.listOf types.str;
description = ''
If the specified units are stopped or restarted, then this
unit is stopped or restarted as well.
'';
};
conflicts = mkOption {
default = [];
type = types.listOf types.str;
description = ''
If the specified units are started, then this unit is stopped
and vice versa.
'';
};
requiredBy = mkOption {
default = [];
type = types.listOf types.str;
description = "Units that require (i.e. depend on and need to go down with) this unit.";
};
wantedBy = mkOption {
default = [];
type = types.listOf types.str;
description = "Units that want (i.e. depend on) this unit.";
};
unitConfig = mkOption {
default = {};
example = { RequiresMountsFor = "/data"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Unit]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.unit</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
restartTriggers = mkOption {
default = [];
type = types.listOf types.unspecified;
description = ''
An arbitrary list of items such as derivations. If any item
in the list changes between reconfigurations, the service will
be restarted.
'';
};
};
serviceOptions = unitOptions // {
environment = mkOption {
default = {};
type = types.attrs; # FIXME
example = { PATH = "/foo/bar/bin"; LANG = "nl_NL.UTF-8"; };
description = "Environment variables passed to the service's processes.";
};
path = mkOption {
default = [];
apply = ps: "${makeSearchPath "bin" ps}:${makeSearchPath "sbin" ps}";
description = ''
Packages added to the service's <envar>PATH</envar>
environment variable. Both the <filename>bin</filename>
and <filename>sbin</filename> subdirectories of each
package are added.
'';
};
serviceConfig = mkOption {
default = {};
example =
{ StartLimitInterval = 10;
RestartSec = 5;
};
type = types.addCheck (types.attrsOf unitOption) checkService;
description = ''
Each attribute in this set specifies an option in the
<literal>[Service]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.service</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
script = mkOption {
type = types.lines;
default = "";
description = "Shell commands executed as the service's main process.";
};
scriptArgs = mkOption {
type = types.str;
default = "";
description = "Arguments passed to the main process script.";
};
preStart = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed before the service's main process
is started.
'';
};
postStart = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed after the service's main process
is started.
'';
};
preStop = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed to stop the service.
'';
};
postStop = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed after the service's main process
has exited.
'';
};
restartIfChanged = mkOption {
type = types.bool;
default = true;
description = ''
Whether the service should be restarted during a NixOS
configuration switch if its definition has changed.
'';
};
stopIfChanged = mkOption {
type = types.bool;
default = true;
description = ''
If set, a changed unit is restarted by calling
<command>systemctl stop</command> in the old configuration,
then <command>systemctl start</command> in the new one.
Otherwise, it is restarted in a single step using
<command>systemctl restart</command> in the new configuration.
The latter is less correct because it runs the
<literal>ExecStop</literal> commands from the new
configuration.
'';
};
startAt = mkOption {
type = types.str;
default = "";
example = "Sun 14:00:00";
description = ''
Automatically start this unit at the given date/time, which
must be in the format described in
<citerefentry><refentrytitle>systemd.time</refentrytitle>
<manvolnum>5</manvolnum></citerefentry>. This is equivalent
to adding a corresponding timer unit with
<option>OnCalendar</option> set to the value given here.
'';
};
};
socketOptions = unitOptions // {
listenStreams = mkOption {
default = [];
type = types.listOf types.str;
example = [ "0.0.0.0:993" "/run/my-socket" ];
description = ''
For each item in this list, a <literal>ListenStream</literal>
option in the <literal>[Socket]</literal> section will be created.
'';
};
socketConfig = mkOption {
default = {};
example = { ListenStream = "/run/my-socket"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Socket]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.socket</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
timerOptions = unitOptions // {
timerConfig = mkOption {
default = {};
example = { OnCalendar = "Sun 14:00:00"; Unit = "foo.service"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Timer]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.timer</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> and
<citerefentry><refentrytitle>systemd.time</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
pathOptions = unitOptions // {
pathConfig = mkOption {
default = {};
example = { PathChanged = "/some/path"; Unit = "changedpath.service"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Path]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.path</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
mountOptions = unitOptions // {
what = mkOption {
example = "/dev/sda1";
type = types.str;
description = "Absolute path of device node, file or other resource. (Mandatory)";
};
where = mkOption {
example = "/mnt";
type = types.str;
description = ''
Absolute path of a directory of the mount point.
Will be created if it doesn't exist. (Mandatory)
'';
};
type = mkOption {
default = "";
example = "ext4";
type = types.str;
description = "File system type.";
};
options = mkOption {
default = "";
example = "noatime";
type = types.commas;
description = "Options used to mount the file system.";
};
mountConfig = mkOption {
default = {};
example = { DirectoryMode = "0775"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Mount]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.mount</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
automountOptions = unitOptions // {
where = mkOption {
example = "/mnt";
type = types.str;
description = ''
Absolute path of a directory of the mount point.
Will be created if it doesn't exist. (Mandatory)
'';
};
automountConfig = mkOption {
default = {};
example = { DirectoryMode = "0775"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Automount]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.automount</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
}