nixpkgs/nixos/lib/systemd-unit-options.nix
2022-02-09 15:14:37 +01:00

553 lines
16 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.

{ lib, systemdUtils }:
with systemdUtils.lib;
with lib;
let
checkService = checkUnitConfig "Service" [
(assertValueOneOf "Type" [
"exec" "simple" "forking" "oneshot" "dbus" "notify" "idle"
])
(assertValueOneOf "Restart" [
"no" "on-success" "on-failure" "on-abnormal" "on-abort" "always"
])
];
in rec {
unitOption = mkOptionType {
name = "systemd option";
merge = loc: defs:
let
defs' = filterOverrides defs;
defs'' = getValues defs';
in
if isList (head defs'')
then concatLists defs''
else mergeEqualOption loc defs';
};
sharedOptions = {
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. Note that <literal>enable=true</literal> does not
make a unit start by default at boot; if you want that, see
<literal>wantedBy</literal>.
'';
};
requiredBy = mkOption {
default = [];
type = types.listOf unitNameType;
description = ''
Units that require (i.e. depend on and need to go down with)
this unit. The discussion under <literal>wantedBy</literal>
applies here as well: inverse <literal>.requires</literal>
symlinks are established.
'';
};
wantedBy = mkOption {
default = [];
type = types.listOf unitNameType;
description = ''
Units that want (i.e. depend on) this unit. The standard way
to make a unit start by default at boot is to set this option
to <literal>[ "multi-user.target" ]</literal>. That's despite
the fact that the systemd.unit(5) manpage says this option
goes in the <literal>[Install]</literal> section that controls
the behaviour of <literal>systemctl enable</literal>. Since
such a process is stateful and thus contrary to the design of
NixOS, setting this option instead causes the equivalent
inverse <literal>.wants</literal> symlink to be present,
establishing the same desired relationship in a stateless way.
'';
};
aliases = mkOption {
default = [];
type = types.listOf unitNameType;
description = "Aliases of that unit.";
};
};
concreteUnitOptions = sharedOptions // {
text = mkOption {
type = types.nullOr types.str;
default = null;
description = "Text of this systemd unit.";
};
unit = mkOption {
internal = true;
description = "The generated unit.";
};
};
commonUnitOptions = sharedOptions // {
description = mkOption {
default = "";
type = types.singleLineStr;
description = "Description of this unit used in systemd messages and progress indicators.";
};
documentation = mkOption {
default = [];
type = types.listOf types.str;
description = "A list of URIs referencing documentation for this unit or its configuration.";
};
requires = mkOption {
default = [];
type = types.listOf unitNameType;
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 unitNameType;
description = ''
Start the specified units when this unit is started.
'';
};
after = mkOption {
default = [];
type = types.listOf unitNameType;
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 unitNameType;
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 unitNameType;
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 unitNameType;
description = ''
If the specified units are stopped or restarted, then this
unit is stopped or restarted as well.
'';
};
conflicts = mkOption {
default = [];
type = types.listOf unitNameType;
description = ''
If the specified units are started, then this unit is stopped
and vice versa.
'';
};
requisite = mkOption {
default = [];
type = types.listOf unitNameType;
description = ''
Similar to requires. However if the units listed are not started,
they will not be started and the transaction will fail.
'';
};
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.
'';
};
reloadTriggers = mkOption {
default = [];
type = types.listOf unitOption;
description = ''
An arbitrary list of items such as derivations. If any item
in the list changes between reconfigurations, the service will
be reloaded. If anything but a reload trigger changes in the
unit file, the unit will be restarted instead.
'';
};
onFailure = mkOption {
default = [];
type = types.listOf unitNameType;
description = ''
A list of one or more units that are activated when
this unit enters the "failed" state.
'';
};
startLimitBurst = mkOption {
type = types.int;
description = ''
Configure unit start rate limiting. Units which are started
more than startLimitBurst times within an interval time
interval are not permitted to start any more.
'';
};
startLimitIntervalSec = mkOption {
type = types.int;
description = ''
Configure unit start rate limiting. Units which are started
more than startLimitBurst times within an interval time
interval are not permitted to start any more.
'';
};
};
serviceOptions = commonUnitOptions // {
environment = mkOption {
default = {};
type = with types; attrsOf (nullOr (oneOf [ str path package ]));
example = { PATH = "/foo/bar/bin"; LANG = "nl_NL.UTF-8"; };
description = "Environment variables passed to the service's processes.";
};
path = mkOption {
default = [];
type = with types; listOf (oneOf [ package str ]);
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 =
{ 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.
'';
};
reload = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed when the service's main process
is reloaded.
'';
};
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.
'';
};
reloadIfChanged = mkOption {
type = types.bool;
default = false;
description = ''
Whether the service should be reloaded during a NixOS
configuration switch if its definition has changed. If
enabled, the value of <option>restartIfChanged</option> is
ignored.
This option should not be used anymore in favor of
<option>reloadTriggers</option> which allows more granular
control of when a service is reloaded and when a service
is restarted.
'';
};
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 = with types; either str (listOf 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>7</manvolnum></citerefentry>. This is equivalent
to adding a corresponding timer unit with
<option>OnCalendar</option> set to the value given here.
'';
apply = v: if isList v then v else [ v ];
};
};
socketOptions = commonUnitOptions // {
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.
'';
};
listenDatagrams = 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>ListenDatagram</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 = commonUnitOptions // {
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>7</manvolnum></citerefentry> for details.
'';
};
};
pathOptions = commonUnitOptions // {
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 = commonUnitOptions // {
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 = commonUnitOptions // {
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.
'';
};
};
targetOptions = commonUnitOptions;
sliceOptions = commonUnitOptions // {
sliceConfig = mkOption {
default = {};
example = { MemoryMax = "2G"; };
type = types.attrsOf unitOption;
description = ''
Each attribute in this set specifies an option in the
<literal>[Slice]</literal> section of the unit. See
<citerefentry><refentrytitle>systemd.slice</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> for details.
'';
};
};
}