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|
{ 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;
in
if isList (head defs').value
then concatMap (def:
if builtins.typeOf def.value == "list"
then def.value
else
throw "The definitions for systemd unit options should be either all lists, representing repeatable options, or all non-lists, but for the option ${showOption loc}, the definitions are a mix of list and non-list ${lib.options.showDefs defs'}"
) defs'
else mergeEqualOption loc defs';
};
sharedOptions = {
enable = mkOption {
default = true;
type = types.bool;
description = lib.mdDoc ''
If set to false, this unit will be a symlink to
/dev/null. This is primarily useful to prevent specific
template instances
(e.g. `serial-getty@ttyS0`) from being
started. Note that `enable=true` does not
make a unit start by default at boot; if you want that, see
`wantedBy`.
'';
};
overrideStrategy = mkOption {
default = "asDropinIfExists";
type = types.enum [ "asDropinIfExists" "asDropin" ];
description = lib.mdDoc ''
Defines how unit configuration is provided for systemd:
`asDropinIfExists` creates a unit file when no unit file is provided by the package
otherwise a drop-in file name `overrides.conf`.
`asDropin` creates a drop-in file named `overrides.conf`.
Mainly needed to define instances for systemd template units (e.g. `systemd-nspawn@mycontainer.service`).
See also systemd.unit(1).
'';
};
requiredBy = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
Units that require (i.e. depend on and need to go down with) this unit.
As discussed in the `wantedBy` option description this also creates
`.requires` symlinks automatically.
'';
};
wantedBy = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
Units that want (i.e. depend on) this unit. The default method for
starting a unit by default at boot time is to set this option to
'["multi-user.target"]' for system services. Likewise for user units
(`systemd.user.<name>.*`) set it to `["default.target"]` to make a unit
start by default when the user `<name>` logs on.
This option creates a `.wants` symlink in the given target that exists
statelessly without the need for running `systemctl enable`.
The in systemd.unit(5) manpage described `[Install]` section however is
not supported because it is a stateful process that does not fit well
into the NixOS design.
'';
};
aliases = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc "Aliases of that unit.";
};
};
concreteUnitOptions = sharedOptions // {
text = mkOption {
type = types.nullOr types.str;
default = null;
description = lib.mdDoc "Text of this systemd unit.";
};
unit = mkOption {
internal = true;
description = lib.mdDoc "The generated unit.";
};
};
commonUnitOptions = {
options = sharedOptions // {
description = mkOption {
default = "";
type = types.singleLineStr;
description = lib.mdDoc "Description of this unit used in systemd messages and progress indicators.";
};
documentation = mkOption {
default = [];
type = types.listOf types.str;
description = lib.mdDoc "A list of URIs referencing documentation for this unit or its configuration.";
};
requires = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
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 = lib.mdDoc ''
Start the specified units when this unit is started.
'';
};
after = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
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 = lib.mdDoc ''
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 = lib.mdDoc ''
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 = lib.mdDoc ''
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 = lib.mdDoc ''
If the specified units are started, then this unit is stopped
and vice versa.
'';
};
requisite = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
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 = lib.mdDoc ''
Each attribute in this set specifies an option in the
`[Unit]` section of the unit. See
{manpage}`systemd.unit(5)` for details.
'';
};
onFailure = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
A list of one or more units that are activated when
this unit enters the "failed" state.
'';
};
onSuccess = mkOption {
default = [];
type = types.listOf unitNameType;
description = lib.mdDoc ''
A list of one or more units that are activated when
this unit enters the "inactive" state.
'';
};
startLimitBurst = mkOption {
type = types.int;
description = lib.mdDoc ''
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 = lib.mdDoc ''
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.
'';
};
};
};
stage2CommonUnitOptions = {
imports = [
commonUnitOptions
];
options = {
restartTriggers = mkOption {
default = [];
type = types.listOf types.unspecified;
description = lib.mdDoc ''
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 = lib.mdDoc ''
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.
'';
};
};
};
stage1CommonUnitOptions = commonUnitOptions;
serviceOptions = { name, config, ... }: {
options = {
environment = mkOption {
default = {};
type = with types; attrsOf (nullOr (oneOf [ str path package ]));
example = { PATH = "/foo/bar/bin"; LANG = "nl_NL.UTF-8"; };
description = lib.mdDoc "Environment variables passed to the service's processes.";
};
path = mkOption {
default = [];
type = with types; listOf (oneOf [ package str ]);
description = lib.mdDoc ''
Packages added to the service's {env}`PATH`
environment variable. Both the {file}`bin`
and {file}`sbin` subdirectories of each
package are added.
'';
};
serviceConfig = mkOption {
default = {};
example =
{ RestartSec = 5;
};
type = types.addCheck (types.attrsOf unitOption) checkService;
description = lib.mdDoc ''
Each attribute in this set specifies an option in the
`[Service]` section of the unit. See
{manpage}`systemd.service(5)` for details.
'';
};
script = mkOption {
type = types.lines;
default = "";
description = lib.mdDoc "Shell commands executed as the service's main process.";
};
scriptArgs = mkOption {
type = types.str;
default = "";
example = "%i";
description = lib.mdDoc
|