depot/third_party/nixpkgs/nixos/modules/services/misc/snapper.nix

363 lines
9.6 KiB
Nix

{
config,
pkgs,
lib,
...
}:
let
cfg = config.services.snapper;
mkValue =
v:
if lib.isList v then
"\"${
lib.concatMapStringsSep " " (lib.escape [
"\\"
" "
]) v
}\""
else if v == true then
"yes"
else if v == false then
"no"
else if lib.isString v then
"\"${v}\""
else
builtins.toJSON v;
mkKeyValue = k: v: "${k}=${mkValue v}";
# "it's recommended to always specify the filesystem type" -- man snapper-configs
defaultOf = k: if k == "FSTYPE" then null else configOptions.${k}.default or null;
safeStr = lib.types.strMatching "[^\n\"]*" // {
description = "string without line breaks or quotes";
descriptionClass = "conjunction";
};
intOrNumberOrRange = lib.types.either lib.types.ints.unsigned (
lib.types.strMatching "[[:digit:]]+(\-[[:digit:]]+)?"
// {
description = "string containing either a number or a range";
descriptionClass = "conjunction";
}
);
configOptions = {
SUBVOLUME = lib.mkOption {
type = lib.types.path;
description = ''
Path of the subvolume or mount point.
This path is a subvolume and has to contain a subvolume named
.snapshots.
See also man:snapper(8) section PERMISSIONS.
'';
};
FSTYPE = lib.mkOption {
type = lib.types.enum [ "btrfs" ];
default = "btrfs";
description = ''
Filesystem type. Only btrfs is stable and tested.
'';
};
ALLOW_GROUPS = lib.mkOption {
type = lib.types.listOf safeStr;
default = [ ];
description = ''
List of groups allowed to operate with the config.
Also see the PERMISSIONS section in man:snapper(8).
'';
};
ALLOW_USERS = lib.mkOption {
type = lib.types.listOf safeStr;
default = [ ];
example = [ "alice" ];
description = ''
List of users allowed to operate with the config. "root" is always
implicitly included.
Also see the PERMISSIONS section in man:snapper(8).
'';
};
TIMELINE_CLEANUP = lib.mkOption {
type = lib.types.bool;
default = false;
description = ''
Defines whether the timeline cleanup algorithm should be run for the config.
'';
};
TIMELINE_CREATE = lib.mkOption {
type = lib.types.bool;
default = false;
description = ''
Defines whether hourly snapshots should be created.
'';
};
TIMELINE_LIMIT_HOURLY = lib.mkOption {
type = intOrNumberOrRange;
default = 10;
description = ''
Limits for timeline cleanup.
'';
};
TIMELINE_LIMIT_DAILY = lib.mkOption {
type = intOrNumberOrRange;
default = 10;
description = ''
Limits for timeline cleanup.
'';
};
TIMELINE_LIMIT_WEEKLY = lib.mkOption {
type = intOrNumberOrRange;
default = 0;
description = ''
Limits for timeline cleanup.
'';
};
TIMELINE_LIMIT_MONTHLY = lib.mkOption {
type = intOrNumberOrRange;
default = 10;
description = ''
Limits for timeline cleanup.
'';
};
TIMELINE_LIMIT_QUARTERLY = lib.mkOption {
type = intOrNumberOrRange;
default = 0;
description = ''
Limits for timeline cleanup.
'';
};
TIMELINE_LIMIT_YEARLY = lib.mkOption {
type = intOrNumberOrRange;
default = 10;
description = ''
Limits for timeline cleanup.
'';
};
};
in
{
options.services.snapper = {
snapshotRootOnBoot = lib.mkOption {
type = lib.types.bool;
default = false;
description = ''
Whether to snapshot root on boot
'';
};
snapshotInterval = lib.mkOption {
type = lib.types.str;
default = "hourly";
description = ''
Snapshot interval.
The format is described in
{manpage}`systemd.time(7)`.
'';
};
persistentTimer = lib.mkOption {
default = false;
type = lib.types.bool;
example = true;
description = ''
Set the `Persistent` option for the
{manpage}`systemd.timer(5)`
which triggers the snapshot immediately if the last trigger
was missed (e.g. if the system was powered down).
'';
};
cleanupInterval = lib.mkOption {
type = lib.types.str;
default = "1d";
description = ''
Cleanup interval.
The format is described in
{manpage}`systemd.time(7)`.
'';
};
filters = lib.mkOption {
type = lib.types.nullOr lib.types.lines;
default = null;
description = ''
Global display difference filter. See man:snapper(8) for more details.
'';
};
configs = lib.mkOption {
default = { };
example = lib.literalExpression ''
{
home = {
SUBVOLUME = "/home";
ALLOW_USERS = [ "alice" ];
TIMELINE_CREATE = true;
TIMELINE_CLEANUP = true;
};
}
'';
description = ''
Subvolume configuration. Any option mentioned in man:snapper-configs(5)
is valid here, even if NixOS doesn't document it.
'';
type = lib.types.attrsOf (
lib.types.submodule {
freeformType = lib.types.attrsOf (
lib.types.oneOf [
(lib.types.listOf safeStr)
lib.types.bool
safeStr
lib.types.number
]
);
options = configOptions;
}
);
};
};
config = lib.mkIf (cfg.configs != { }) (
let
documentation = [
"man:snapper(8)"
"man:snapper-configs(5)"
];
in
{
environment = {
systemPackages = [ pkgs.snapper ];
# Note: snapper/config-templates/default is only needed for create-config
# which is not the NixOS way to configure.
etc =
{
"sysconfig/snapper".text = ''
SNAPPER_CONFIGS="${lib.concatStringsSep " " (builtins.attrNames cfg.configs)}"
'';
}
// (lib.mapAttrs' (
name: subvolume:
lib.nameValuePair "snapper/configs/${name}" ({
text = lib.generators.toKeyValue { inherit mkKeyValue; } (
lib.filterAttrs (k: v: v != defaultOf k) subvolume
);
})
) cfg.configs)
// (lib.optionalAttrs (cfg.filters != null) { "snapper/filters/default.txt".text = cfg.filters; });
};
services.dbus.packages = [ pkgs.snapper ];
systemd.services.snapperd = {
description = "DBus interface for snapper";
inherit documentation;
serviceConfig = {
Type = "dbus";
BusName = "org.opensuse.Snapper";
ExecStart = "${pkgs.snapper}/bin/snapperd";
CapabilityBoundingSet = "CAP_DAC_OVERRIDE CAP_FOWNER CAP_CHOWN CAP_FSETID CAP_SETFCAP CAP_SYS_ADMIN CAP_SYS_MODULE CAP_IPC_LOCK CAP_SYS_NICE";
LockPersonality = true;
NoNewPrivileges = false;
PrivateNetwork = true;
ProtectHostname = true;
RestrictAddressFamilies = "AF_UNIX";
RestrictRealtime = true;
};
};
systemd.services.snapper-timeline = {
description = "Timeline of Snapper Snapshots";
inherit documentation;
requires = [ "local-fs.target" ];
serviceConfig.ExecStart = "${pkgs.snapper}/lib/snapper/systemd-helper --timeline";
};
systemd.timers.snapper-timeline = {
wantedBy = [ "timers.target" ];
timerConfig = {
Persistent = cfg.persistentTimer;
OnCalendar = cfg.snapshotInterval;
};
};
systemd.services.snapper-cleanup = {
description = "Cleanup of Snapper Snapshots";
inherit documentation;
serviceConfig.ExecStart = "${pkgs.snapper}/lib/snapper/systemd-helper --cleanup";
};
systemd.timers.snapper-cleanup = {
description = "Cleanup of Snapper Snapshots";
inherit documentation;
wantedBy = [ "timers.target" ];
requires = [ "local-fs.target" ];
timerConfig.OnBootSec = "10m";
timerConfig.OnUnitActiveSec = cfg.cleanupInterval;
};
systemd.services.snapper-boot = lib.mkIf cfg.snapshotRootOnBoot {
description = "Take snapper snapshot of root on boot";
inherit documentation;
serviceConfig.ExecStart = "${pkgs.snapper}/bin/snapper --config root create --cleanup-algorithm number --description boot";
serviceConfig.Type = "oneshot";
requires = [ "local-fs.target" ];
wantedBy = [ "multi-user.target" ];
unitConfig.ConditionPathExists = "/etc/snapper/configs/root";
};
assertions = lib.concatMap (
name:
let
sub = cfg.configs.${name};
in
[
{
assertion = !(sub ? extraConfig);
message = ''
The option definition `services.snapper.configs.${name}.extraConfig' no longer has any effect; please remove it.
The contents of this option should be migrated to attributes on `services.snapper.configs.${name}'.
'';
}
]
++
map
(attr: {
assertion = !(lib.hasAttr attr sub);
message = ''
The option definition `services.snapper.configs.${name}.${attr}' has been renamed to `services.snapper.configs.${name}.${lib.toUpper attr}'.
'';
})
[
"fstype"
"subvolume"
]
) (lib.attrNames cfg.configs);
}
);
meta.maintainers = with lib.maintainers; [ Djabx ];
}