disko/lib/default.nix
2024-06-19 18:46:17 +00:00

606 lines
21 KiB
Nix

{ lib ? import <nixpkgs/lib>
, rootMountPoint ? "/mnt"
, makeTest ? import <nixpkgs/nixos/tests/make-test-python.nix>
, eval-config ? import <nixpkgs/nixos/lib/eval-config.nix>
}:
with lib;
with builtins;
let
outputs = import ../default.nix { inherit lib diskoLib; };
diskoLib = {
# like make-disk-image.nix from nixpkgs, but with disko config
makeDiskImages = args: (import ./make-disk-image.nix ({ inherit diskoLib; } // args)).pure;
# a version of makeDiskImage which runs outside of the store
makeDiskImagesScript = args: (import ./make-disk-image.nix ({ inherit diskoLib; } // args)).impure;
testLib = import ./tests.nix { inherit lib makeTest eval-config; };
# like lib.types.oneOf but instead of a list takes an attrset
# uses the field "type" to find the correct type in the attrset
subType = { types, extraArgs ? { parent = { type = "rootNode"; name = "root"; }; } }: lib.mkOptionType {
name = "subType";
description = "one of ${concatStringsSep "," (attrNames types)}";
check = x: if x ? type then types.${x.type}.check x else throw "No type option set in:\n${generators.toPretty {} x}";
merge = loc: foldl'
(_res: def: types.${def.value.type}.merge loc [
# we add a dummy root parent node to render documentation
(lib.recursiveUpdate { value._module.args = extraArgs; } def)
])
{ };
nestedTypes = types;
};
# option for valid contents of partitions (basically like devices, but without tables)
partitionType = extraArgs: lib.mkOption {
type = lib.types.nullOr (diskoLib.subType {
types = { inherit (diskoLib.types) btrfs filesystem zfs mdraid luks lvm_pv swap; };
inherit extraArgs;
});
default = null;
description = "The type of partition";
};
# option for valid contents of devices
deviceType = extraArgs: lib.mkOption {
type = lib.types.nullOr (diskoLib.subType {
types = { inherit (diskoLib.types) table gpt btrfs filesystem zfs mdraid luks lvm_pv swap; };
inherit extraArgs;
});
default = null;
description = "The type of device";
};
/* deepMergeMap takes a function and a list of attrsets and deep merges them
deepMergeMap :: (AttrSet -> AttrSet ) -> [ AttrSet ] -> Attrset
Example:
deepMergeMap (x: x.t = "test") [ { x = { y = 1; z = 3; }; } { x = { bla = 234; }; } ]
=> { x = { y = 1; z = 3; bla = 234; t = "test"; }; }
*/
deepMergeMap = f: foldr (attr: acc: (recursiveUpdate acc (f attr))) { };
/* get a device and an index to get the matching device name
deviceNumbering :: str -> int -> str
Example:
deviceNumbering "/dev/sda" 3
=> "/dev/sda3"
deviceNumbering "/dev/disk/by-id/xxx" 2
=> "/dev/disk/by-id/xxx-part2"
*/
deviceNumbering = dev: index:
if match "/dev/([vs]|(xv)d).+" dev != null then
dev + toString index # /dev/{s,v,xv}da style
else if match "/dev/(disk|zvol)/.+" dev != null then
"${dev}-part${toString index}" # /dev/disk/by-id/xxx style, also used by zfs's zvolumes
else if match "/dev/((nvme|mmcblk).+|md/.*[[:digit:]])" dev != null then
"${dev}p${toString index}" # /dev/nvme0n1p1 style
else if match "/dev/md/.+" dev != null then
"${dev}${toString index}" # /dev/md/raid1 style
else if match "/dev/mapper/.+" dev != null then
"${dev}${toString index}" # /dev/mapper/vg-lv1 style
else if match "/dev/loop[[:digit:]]+" dev != null
then "${dev}p${toString index}" # /dev/mapper/vg-lv1 style
else
abort ''
${dev} seems not to be a supported disk format. Please add this to disko in https://github.com/nix-community/disko/blob/master/lib/default.nix
'';
/* get the index an item in a list
indexOf :: (a -> bool) -> [a] -> int -> int
Example:
indexOf (x: x == 2) [ 1 2 3 ] 0
=> 2
indexOf (x: x == "x") [ 1 2 3 ] 0
=> 0
*/
indexOf = f: list: fallback:
let
iter = index: list:
if list == [ ] then
fallback
else if f (head list) then
index
else
iter (index + 1) (tail list);
in
iter 1 list;
/* indent takes a multiline string and indents it by 2 spaces starting on the second line
indent :: str -> str
Example:
indent "test\nbla"
=> "test\n bla"
*/
indent = replaceStrings [ "\n" ] [ "\n " ];
/* A nix option type representing a json datastructure, vendored from nixpkgs to avoid dependency on pkgs */
jsonType =
let
valueType = lib.types.nullOr
(lib.types.oneOf [
lib.types.bool
lib.types.int
lib.types.float
lib.types.str
lib.types.path
(lib.types.attrsOf valueType)
(lib.types.listOf valueType)
]) // {
description = "JSON value";
};
in
valueType;
/* Given a attrset of deviceDependencies and a devices attrset
returns a sorted list by deviceDependencies. aborts if a loop is found
sortDevicesByDependencies :: AttrSet -> AttrSet -> [ [ str str ] ]
*/
sortDevicesByDependencies = deviceDependencies: devices:
let
dependsOn = a: b:
elem a (attrByPath b [ ] deviceDependencies);
maybeSortedDevices = toposort dependsOn (diskoLib.deviceList devices);
in
if (hasAttr "cycle" maybeSortedDevices) then
abort "detected a cycle in your disk setup: ${maybeSortedDevices.cycle}"
else
maybeSortedDevices.result;
/* Takes a devices attrSet and returns it as a list
deviceList :: AttrSet -> [ [ str str ] ]
Example:
deviceList { zfs.pool1 = {}; zfs.pool2 = {}; mdadm.raid1 = {}; }
=> [ [ "zfs" "pool1" ] [ "zfs" "pool2" ] [ "mdadm" "raid1" ] ]
*/
deviceList = devices:
concatLists (mapAttrsToList (n: v: (map (x: [ n x ]) (attrNames v))) devices);
/* Takes either a string or null and returns the string or an empty string
maybeStr :: Either (str null) -> str
Example:
maybeStr null
=> ""
maybeSTr "hello world"
=> "hello world"
*/
maybeStr = x: optionalString (x != null) x;
/* Takes a Submodules config and options argument and returns a serializable
subset of config variables as a shell script snippet.
*/
defineHookVariables = { options }:
let
sanitizeName = lib.replaceStrings [ "-" ] [ "_" ];
isAttrsOfSubmodule = o: o.type.name == "attrsOf" && o.type.nestedTypes.elemType.name == "submodule";
isSerializable = n: o: !(
lib.hasPrefix "_" n
|| lib.hasSuffix "Hook" n
|| isAttrsOfSubmodule o
# TODO don't hardcode diskoLib.subType options.
|| n == "content" || n == "partitions" || n == "datasets" || n == "swap"
);
in
lib.toShellVars
(lib.mapAttrs'
(n: o: lib.nameValuePair (sanitizeName n) o.value)
(lib.filterAttrs isSerializable options));
mkHook = description: lib.mkOption {
inherit description;
type = lib.types.lines;
default = "";
};
mkSubType = module: lib.types.submodule [
module
{
options = {
preCreateHook = diskoLib.mkHook "shell commands to run before create";
postCreateHook = diskoLib.mkHook "shell commands to run after create";
preMountHook = diskoLib.mkHook "shell commands to run before mount";
postMountHook = diskoLib.mkHook "shell commands to run after mount";
};
config._module.args = {
inherit diskoLib rootMountPoint;
};
}
];
mkCreateOption = { config, options, default }@attrs:
lib.mkOption {
internal = true;
readOnly = true;
type = lib.types.str;
default = ''
( # ${config.type} ${concatMapStringsSep " " (n: toString (config.${n} or "")) ["name" "device" "format" "mountpoint"]} #
${diskoLib.indent (diskoLib.defineHookVariables { inherit options; })}
${diskoLib.indent config.preCreateHook}
${diskoLib.indent attrs.default}
${diskoLib.indent config.postCreateHook}
)
'';
description = "Creation script";
};
mkMountOption = { config, options, default }@attrs:
lib.mkOption {
internal = true;
readOnly = true;
type = diskoLib.jsonType;
default = lib.mapAttrsRecursive
(_name: value:
if builtins.isString value then ''
(
${diskoLib.indent (diskoLib.defineHookVariables { inherit options; })}
${diskoLib.indent config.preMountHook}
${diskoLib.indent value}
${diskoLib.indent config.postMountHook}
)
'' else value)
attrs.default;
description = "Mount script";
};
/* Writer for optionally checking bash scripts before writing them to the store
writeCheckedBash :: AttrSet -> str -> str -> derivation
*/
writeCheckedBash = { pkgs, checked ? false, noDeps ? false }: pkgs.writers.makeScriptWriter {
interpreter = if noDeps then "/usr/bin/env bash" else "${pkgs.bash}/bin/bash";
check = lib.optionalString (checked && !pkgs.hostPlatform.isRiscV64 && !pkgs.hostPlatform.isx86_32) (pkgs.writeScript "check" ''
set -efu
${pkgs.shellcheck}/bin/shellcheck -e SC2034 "$1"
'');
};
/* Takes a disko device specification, returns an attrset with metadata
meta :: lib.types.devices -> AttrSet
*/
meta = toplevel: toplevel._meta;
/* Takes a disko device specification and returns a string which formats the disks
create :: lib.types.devices -> str
*/
create = toplevel: toplevel._create;
/* Takes a disko device specification and returns a string which mounts the disks
mount :: lib.types.devices -> str
*/
mount = toplevel: toplevel._mount;
/* takes a disko device specification and returns a string which unmounts, destroys all disks and then runs create and mount
zapCreateMount :: lib.types.devices -> str
*/
zapCreateMount = toplevel:
''
set -efux
${toplevel._disko}
'';
/* Takes a disko device specification and returns a nixos configuration
config :: lib.types.devices -> nixosConfig
*/
config = toplevel: toplevel._config;
/* Takes a disko device specification and returns a function to get the needed packages to format/mount the disks
packages :: lib.types.devices -> pkgs -> [ derivation ]
*/
packages = toplevel: toplevel._packages;
optionTypes = rec {
filename = lib.mkOptionType {
name = "filename";
check = isString;
merge = mergeOneOption;
description = "A filename";
};
absolute-pathname = lib.mkOptionType {
name = "absolute pathname";
check = x: isString x && substring 0 1 x == "/" && pathname.check x;
merge = mergeOneOption;
description = "An absolute path";
};
pathname = lib.mkOptionType {
name = "pathname";
check = x:
let
# The filter is used to normalize paths, i.e. to remove duplicated and
# trailing slashes. It also removes leading slashes, thus we have to
# check for "/" explicitly below.
xs = filter (s: stringLength s > 0) (splitString "/" x);
in
isString x && (x == "/" || (length xs > 0 && all filename.check xs));
merge = mergeOneOption;
description = "A path name";
};
};
/* topLevel type of the disko config, takes attrsets of disks, mdadms, zpools, nodevs, and lvm vgs.
*/
toplevel = lib.types.submodule (cfg:
let
devices = { inherit (cfg.config) disk mdadm zpool lvm_vg nodev; };
in
{
options = {
disk = lib.mkOption {
type = lib.types.attrsOf diskoLib.types.disk;
default = { };
description = "Block device";
};
mdadm = lib.mkOption {
type = lib.types.attrsOf diskoLib.types.mdadm;
default = { };
description = "mdadm device";
};
zpool = lib.mkOption {
type = lib.types.attrsOf diskoLib.types.zpool;
default = { };
description = "ZFS pool device";
};
lvm_vg = lib.mkOption {
type = lib.types.attrsOf diskoLib.types.lvm_vg;
default = { };
description = "LVM VG device";
};
nodev = lib.mkOption {
type = lib.types.attrsOf diskoLib.types.nodev;
default = { };
description = "A non-block device";
};
_meta = lib.mkOption {
internal = true;
description = ''
meta informationen generated by disko
currently used for building a dependency list so we know in which order to create the devices
'';
default = diskoLib.deepMergeMap (dev: dev._meta) (flatten (map attrValues (attrValues devices)));
};
_packages = lib.mkOption {
internal = true;
description = ''
packages required by the disko configuration
coreutils is always included
'';
default = pkgs: unique ((flatten (map (dev: dev._pkgs pkgs) (flatten (map attrValues (attrValues devices))))) ++ [ pkgs.coreutils-full ]);
};
_scripts = lib.mkOption {
internal = true;
description = ''
The scripts generated by disko
'';
default = { pkgs, checked ? false }: {
destroyScript = (diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-destroy" ''
export PATH=${lib.makeBinPath (with pkgs; [
util-linux
e2fsprogs
mdadm
zfs
lvm2
bash
jq
gnused
gawk
coreutils-full
])}:$PATH
${cfg.config._destroy}
'';
formatScript = (diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-format" ''
export PATH=${lib.makeBinPath (cfg.config._packages pkgs)}:$PATH
${cfg.config._create}
'';
mountScript = (diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-mount" ''
export PATH=${lib.makeBinPath (cfg.config._packages pkgs)}:$PATH
${cfg.config._mount}
'';
diskoScript = (diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko" ''
export PATH=${lib.makeBinPath ((cfg.config._packages pkgs) ++ [ pkgs.bash ])}:$PATH
${cfg.config._disko}
'';
# These are useful to skip copying executables uploading a script to an in-memory installer
destroyScriptNoDeps = (diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-destroy" ''
${cfg.config._destroy}
'';
formatScriptNoDeps = (diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-format" ''
${cfg.config._create}
'';
mountScriptNoDeps = (diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-mount" ''
${cfg.config._mount}
'';
diskoScriptNoDeps = (diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko" ''
${cfg.config._disko}
'';
};
};
_destroy = lib.mkOption {
internal = true;
type = lib.types.str;
description = ''
The script to unmount (& destroy) all devices defined by disko.devices
'';
default = ''
umount -Rv "${rootMountPoint}" || :
# shellcheck disable=SC2043
for dev in ${toString (lib.catAttrs "device" (lib.attrValues devices.disk))}; do
$BASH ${../disk-deactivate}/disk-deactivate "$dev"
done
'';
};
_create = lib.mkOption {
internal = true;
type = lib.types.str;
description = ''
The script to create all devices defined by disko.devices
'';
default =
let
sortedDeviceList = diskoLib.sortDevicesByDependencies (cfg.config._meta.deviceDependencies or { }) devices;
in
''
set -efux
disko_devices_dir=$(mktemp -d)
trap 'rm -rf "$disko_devices_dir"' EXIT
mkdir -p "$disko_devices_dir"
${concatMapStrings (dev: (attrByPath (dev ++ [ "_create" ]) {} devices)) sortedDeviceList}
'';
};
_mount = lib.mkOption {
internal = true;
type = lib.types.str;
description = ''
The script to mount all devices defined by disko.devices
'';
default =
let
fsMounts = diskoLib.deepMergeMap (dev: dev._mount.fs or { }) (flatten (map attrValues (attrValues devices)));
sortedDeviceList = diskoLib.sortDevicesByDependencies (cfg.config._meta.deviceDependencies or { }) devices;
in
''
set -efux
# first create the necessary devices
${concatMapStrings (dev: (attrByPath (dev ++ [ "_mount" ]) {} devices).dev or "") sortedDeviceList}
# and then mount the filesystems in alphabetical order
${concatStrings (attrValues fsMounts)}
'';
};
_disko = lib.mkOption {
internal = true;
type = lib.types.str;
description = ''
The script to umount, create and mount all devices defined by disko.devices
'';
default = ''
${cfg.config._destroy}
${cfg.config._create}
${cfg.config._mount}
'';
};
_config = lib.mkOption {
internal = true;
description = ''
The NixOS config generated by disko
'';
default =
let
configKeys = flatten (map attrNames (flatten (map (dev: dev._config) (flatten (map attrValues (attrValues devices))))));
collectedConfigs = flatten (map (dev: dev._config) (flatten (map attrValues (attrValues devices))));
in
lib.genAttrs configKeys (key: lib.mkMerge (lib.catAttrs key collectedConfigs));
};
};
});
# import all the types from the types directory
types = lib.listToAttrs (
map
(file: lib.nameValuePair
(lib.removeSuffix ".nix" file)
(diskoLib.mkSubType ./types/${file})
)
(lib.attrNames (builtins.readDir ./types))
);
# render types into an json serializable format
serializeType = type:
let
options = lib.filter (x: !lib.hasPrefix "_" x) (lib.attrNames type.options);
in
lib.listToAttrs (
map
(option: lib.nameValuePair
option
type.options.${option}
)
options
);
typesSerializerLib = {
rootMountPoint = "";
options = null;
config._module.args.name = "self.name";
lib = {
mkOption = option: {
inherit (option) type description;
default = option.default or null;
};
types = {
attrsOf = subType: {
type = "attrsOf";
inherit subType;
};
listOf = subType: {
type = "listOf";
inherit subType;
};
nullOr = subType: {
type = "nullOr";
inherit subType;
};
enum = choices: {
type = "enum";
inherit choices;
};
str = "str";
bool = "bool";
int = "int";
submodule = x: x { inherit (diskoLib.typesSerializerLib) lib config options; };
};
};
diskoLib = {
optionTypes.absolute-pathname = "absolute-pathname";
deviceType = "devicetype";
partitionType = "partitiontype";
subType = types: "onOf ${toString (lib.attrNames types)}";
};
};
jsonTypes = lib.listToAttrs (
map
(file: lib.nameValuePair
(lib.removeSuffix ".nix" file)
(diskoLib.serializeType (import ./types/${file} diskoLib.typesSerializerLib))
)
(lib.attrNames (builtins.readDir ./types))
);
} // outputs;
in
diskoLib