Merge pull request #268997 from nbraud/nixos/systemd/refactor

nixos/systemd: Refactor & link manpages in option descriptions

nixos/modules/system/boot/systemd.nix

···
 {
   ###### interface
 
-  options = {
+  options.systemd = {
 
-    systemd.package = mkOption {
-      default = pkgs.systemd;
-      defaultText = literalExpression "pkgs.systemd";
-      type = types.package;
-      description = lib.mdDoc "The systemd package.";
-    };
+    package = mkPackageOption pkgs "systemd" {};
 
-    systemd.units = mkOption {
-      description = lib.mdDoc "Definition of systemd units.";
+    units = mkOption {
+      description = "Definition of systemd units; see {manpage}`systemd.unit(5)`.";
       default = {};
       type = systemdUtils.types.units;
     };
 
-    systemd.packages = mkOption {
+    packages = mkOption {
       default = [];
       type = types.listOf types.package;
       example = literalExpression "[ pkgs.systemd-cryptsetup-generator ]";
-      description = lib.mdDoc "Packages providing systemd units and hooks.";
+      description = "Packages providing systemd units and hooks.";
     };
 
-    systemd.targets = mkOption {
+    targets = mkOption {
       default = {};
       type = systemdUtils.types.targets;
-      description = lib.mdDoc "Definition of systemd target units.";
+      description = "Definition of systemd target units; see {manpage}`systemd.target(5)`";
     };
 
-    systemd.services = mkOption {
+    services = mkOption {
       default = {};
       type = systemdUtils.types.services;
-      description = lib.mdDoc "Definition of systemd service units.";
+      description = "Definition of systemd service units; see {manpage}`systemd.service(5)`.";
     };
 
-    systemd.sockets = mkOption {
+    sockets = mkOption {
       default = {};
       type = systemdUtils.types.sockets;
-      description = lib.mdDoc "Definition of systemd socket units.";
+      description = "Definition of systemd socket units; see {manpage}`systemd.socket(5)`.";
     };
 
-    systemd.timers = mkOption {
+    timers = mkOption {
       default = {};
       type = systemdUtils.types.timers;
-      description = lib.mdDoc "Definition of systemd timer units.";
+      description = "Definition of systemd timer units; see {manpage}`systemd.timer(5)`.";
     };
 
-    systemd.paths = mkOption {
+    paths = mkOption {
       default = {};
       type = systemdUtils.types.paths;
-      description = lib.mdDoc "Definition of systemd path units.";
+      description = "Definition of systemd path units; see {manpage}`systemd.path(5)`.";
     };
 
-    systemd.mounts = mkOption {
+    mounts = mkOption {
       default = [];
       type = systemdUtils.types.mounts;
-      description = lib.mdDoc ''
-        Definition of systemd mount units.
-        This is a list instead of an attrSet, because systemd mandates the names to be derived from
-        the 'where' attribute.
+      description = ''
+        Definition of systemd mount units; see {manpage}`systemd.mount(5)`.
+
+        This is a list instead of an attrSet, because systemd mandates
+        the names to be derived from the `where` attribute.
       '';
     };
 
-    systemd.automounts = mkOption {
+    automounts = mkOption {
       default = [];
       type = systemdUtils.types.automounts;
-      description = lib.mdDoc ''
-        Definition of systemd automount units.
-        This is a list instead of an attrSet, because systemd mandates the names to be derived from
-        the 'where' attribute.
+      description = ''
+        Definition of systemd automount units; see {manpage}`systemd.automount(5)`.
+
+        This is a list instead of an attrSet, because systemd mandates
+        the names to be derived from the `where` attribute.
       '';
     };
 
-    systemd.slices = mkOption {
+    slices = mkOption {
       default = {};
       type = systemdUtils.types.slices;
-      description = lib.mdDoc "Definition of slice configurations.";
+      description = "Definition of slice configurations; see {manpage}`systemd.slice(5)`.";
     };
 
-    systemd.generators = mkOption {
+    generators = mkOption {
       type = types.attrsOf types.path;
       default = {};
       example = { systemd-gpt-auto-generator = "/dev/null"; };
-      description = lib.mdDoc ''
-        Definition of systemd generators.
+      description = ''
+        Definition of systemd generators; see {manpage}`systemd.generator(5)`.
+
         For each `NAME = VALUE` pair of the attrSet, a link is generated from
         `/etc/systemd/system-generators/NAME` to `VALUE`.
       '';
     };
 
-    systemd.shutdown = mkOption {
+    shutdown = mkOption {
       type = types.attrsOf types.path;
       default = {};
-      description = lib.mdDoc ''
+      description = ''
         Definition of systemd shutdown executables.
         For each `NAME = VALUE` pair of the attrSet, a link is generated from
         `/etc/systemd/system-shutdown/NAME` to `VALUE`.
       '';
     };
 
-    systemd.defaultUnit = mkOption {
+    defaultUnit = mkOption {
       default = "multi-user.target";
       type = types.str;
-      description = lib.mdDoc "Default unit started when the system boots.";
+      description = ''
+        Default unit started when the system boots; see {manpage}`systemd.special(7)`.
+      '';
     };
 
-    systemd.ctrlAltDelUnit = mkOption {
+    ctrlAltDelUnit = mkOption {
       default = "reboot.target";
       type = types.str;
       example = "poweroff.target";
-      description = lib.mdDoc ''
-        Target that should be started when Ctrl-Alt-Delete is pressed.
+      description = ''
+        Target that should be started when Ctrl-Alt-Delete is pressed;
+        see {manpage}`systemd.special(7)`.
       '';
     };
 
-    systemd.globalEnvironment = mkOption {
+    globalEnvironment = mkOption {
       type = with types; attrsOf (nullOr (oneOf [ str path package ]));
       default = {};
       example = { TZ = "CET"; };
-      description = lib.mdDoc ''
+      description = ''
         Environment variables passed to *all* systemd units.
       '';
     };
 
-    systemd.managerEnvironment = mkOption {
+    managerEnvironment = mkOption {
       type = with types; attrsOf (nullOr (oneOf [ str path package ]));
       default = {};
       example = { SYSTEMD_LOG_LEVEL = "debug"; };
-      description = lib.mdDoc ''
+      description = ''
         Environment variables of PID 1. These variables are
         *not* passed to started units.
       '';
     };
 
-    systemd.enableCgroupAccounting = mkOption {
+    enableCgroupAccounting = mkOption {
       default = true;
       type = types.bool;
-      description = lib.mdDoc ''
-        Whether to enable cgroup accounting.
+      description = ''
+        Whether to enable cgroup accounting; see {manpage}`cgroups(7)`.
       '';
     };
 
-    systemd.enableUnifiedCgroupHierarchy = mkOption {
+    enableUnifiedCgroupHierarchy = mkOption {
       default = true;
       type = types.bool;
-      description = lib.mdDoc ''
-        Whether to enable the unified cgroup hierarchy (cgroupsv2).
+      description = ''
+        Whether to enable the unified cgroup hierarchy (cgroupsv2); see {manpage}`cgroups(7)`.
       '';
     };
 
-    systemd.extraConfig = mkOption {
+    extraConfig = mkOption {
       default = "";
       type = types.lines;
       example = "DefaultLimitCORE=infinity";
-      description = lib.mdDoc ''
-        Extra config options for systemd. See systemd-system.conf(5) man page
+      description = ''
+        Extra config options for systemd. See {manpage}`systemd-system.conf(5)` man page
         for available options.
       '';
     };
 
-    systemd.sleep.extraConfig = mkOption {
+    sleep.extraConfig = mkOption {
       default = "";
       type = types.lines;
       example = "HibernateDelaySec=1h";
-      description = lib.mdDoc ''
+      description = ''
         Extra config options for systemd sleep state logic.
-        See sleep.conf.d(5) man page for available options.
+        See {manpage}`sleep.conf.d(5)` man page for available options.
       '';
     };
 
-    systemd.additionalUpstreamSystemUnits = mkOption {
+    additionalUpstreamSystemUnits = mkOption {
       default = [ ];
       type = types.listOf types.str;
       example = [ "debug-shell.service" "systemd-quotacheck.service" ];
-      description = lib.mdDoc ''
+      description = ''
         Additional units shipped with systemd that shall be enabled.
       '';
     };
 
-    systemd.suppressedSystemUnits = mkOption {
+    suppressedSystemUnits = mkOption {
       default = [ ];
       type = types.listOf types.str;
       example = [ "systemd-backlight@.service" ];
-      description = lib.mdDoc ''
+      description = ''
         A list of units to skip when generating system systemd configuration directory. This has
         priority over upstream units, {option}`systemd.units`, and
         {option}`systemd.additionalUpstreamSystemUnits`. The main purpose of this is to
···
       '';
     };
 
-    systemd.watchdog.device = mkOption {
+    watchdog.device = mkOption {
       type = types.nullOr types.path;
       default = null;
       example = "/dev/watchdog";
-      description = lib.mdDoc ''
+      description = ''
         The path to a hardware watchdog device which will be managed by systemd.
-        If not specified, systemd will default to /dev/watchdog.
+        If not specified, systemd will default to `/dev/watchdog`.
       '';
     };
 
-    systemd.watchdog.runtimeTime = mkOption {
+    watchdog.runtimeTime = mkOption {
       type = types.nullOr types.str;
       default = null;
       example = "30s";
-      description = lib.mdDoc ''
+      description = ''
         The amount of time which can elapse before a watchdog hardware device
-        will automatically reboot the system. Valid time units include "ms",
-        "s", "min", "h", "d", and "w".
+        will automatically reboot the system.
+
+        Valid time units include "ms", "s", "min", "h", "d", and "w";
+        see {manpage}`systemd.time(7)`.
       '';
     };
 
-    systemd.watchdog.rebootTime = mkOption {
+    watchdog.rebootTime = mkOption {
       type = types.nullOr types.str;
       default = null;
       example = "10m";
-      description = lib.mdDoc ''
+      description = ''
         The amount of time which can elapse after a reboot has been triggered
         before a watchdog hardware device will automatically reboot the system.
-        Valid time units include "ms", "s", "min", "h", "d", and "w". If left
-        `null`, systemd will use its default of `10min`; see also {command}`man
-        5 systemd-system.conf`.
+        If left `null`, systemd will use its default of 10 minutes;
+        see {manpage}`systemd-system.conf(5)`.
+
+        Valid time units include "ms", "s", "min", "h", "d", and "w";
+        see also {manpage}`systemd.time(7)`.
       '';
     };
 
-    systemd.watchdog.kexecTime = mkOption {
+    watchdog.kexecTime = mkOption {
       type = types.nullOr types.str;
       default = null;
       example = "10m";
-      description = lib.mdDoc ''
-        The amount of time which can elapse when kexec is being executed before
+      description = ''
+        The amount of time which can elapse when `kexec` is being executed before
         a watchdog hardware device will automatically reboot the system. This
-        option should only be enabled if reloadTime is also enabled. Valid
-        time units include "ms", "s", "min", "h", "d", and "w".
+        option should only be enabled if `reloadTime` is also enabled;
+        see {manpage}`kexec(8)`.
+
+        Valid time units include "ms", "s", "min", "h", "d", and "w";
+        see also {manpage}`systemd.time(7)`.
       '';
     };
   };
···
       "systemd/system.conf".text = ''
         [Manager]
         ManagerEnvironment=${lib.concatStringsSep " " (lib.mapAttrsToList (n: v: "${n}=${lib.escapeShellArg v}") cfg.managerEnvironment)}
-        ${optionalString config.systemd.enableCgroupAccounting ''
+        ${optionalString cfg.enableCgroupAccounting ''
           DefaultCPUAccounting=yes
           DefaultIOAccounting=yes
           DefaultBlockIOAccounting=yes
           DefaultIPAccounting=yes
         ''}
         DefaultLimitCORE=infinity
-        ${optionalString (config.systemd.watchdog.device != null) ''
-          WatchdogDevice=${config.systemd.watchdog.device}
+        ${optionalString (cfg.watchdog.device != null) ''
+          WatchdogDevice=${cfg.watchdog.device}
         ''}
-        ${optionalString (config.systemd.watchdog.runtimeTime != null) ''
-          RuntimeWatchdogSec=${config.systemd.watchdog.runtimeTime}
+        ${optionalString (cfg.watchdog.runtimeTime != null) ''
+          RuntimeWatchdogSec=${cfg.watchdog.runtimeTime}
         ''}
-        ${optionalString (config.systemd.watchdog.rebootTime != null) ''
-          RebootWatchdogSec=${config.systemd.watchdog.rebootTime}
+        ${optionalString (cfg.watchdog.rebootTime != null) ''
+          RebootWatchdogSec=${cfg.watchdog.rebootTime}
         ''}
-        ${optionalString (config.systemd.watchdog.kexecTime != null) ''
-          KExecWatchdogSec=${config.systemd.watchdog.kexecTime}
+        ${optionalString (cfg.watchdog.kexecTime != null) ''
+          KExecWatchdogSec=${cfg.watchdog.kexecTime}
         ''}
 
-        ${config.systemd.extraConfig}
+        ${cfg.extraConfig}
       '';
 
       "systemd/sleep.conf".text = ''
         [Sleep]
-        ${config.systemd.sleep.extraConfig}
+        ${cfg.sleep.extraConfig}
       '';
 
       "systemd/system-generators" = { source = hooks "generators" cfg.generators; };