nixpkgs/nixos/modules/misc/documentation.nix
2021-03-14 02:18:40 +01:00

272 lines
9.2 KiB
Nix

{ config, lib, pkgs, baseModules, extraModules, modules, modulesPath, ... }:
with lib;
let
cfg = config.documentation;
manualModules = baseModules ++ optionals cfg.nixos.includeAllModules (extraModules ++ modules);
/* For the purpose of generating docs, evaluate options with each derivation
in `pkgs` (recursively) replaced by a fake with path "\${pkgs.attribute.path}".
It isn't perfect, but it seems to cover a vast majority of use cases.
Caveat: even if the package is reached by a different means,
the path above will be shown and not e.g. `${config.services.foo.package}`. */
manual = import ../../doc/manual rec {
inherit pkgs config;
version = config.system.nixos.release;
revision = "release-${version}";
extraSources = cfg.nixos.extraModuleSources;
options =
let
scrubbedEval = evalModules {
modules = [ { nixpkgs.localSystem = config.nixpkgs.localSystem; } ] ++ manualModules;
args = (config._module.args) // { modules = [ ]; };
specialArgs = {
pkgs = scrubDerivations "pkgs" pkgs;
inherit modulesPath;
};
};
scrubDerivations = namePrefix: pkgSet: mapAttrs
(name: value:
let wholeName = "${namePrefix}.${name}"; in
if isAttrs value then
scrubDerivations wholeName value
// (optionalAttrs (isDerivation value) { outPath = "\${${wholeName}}"; })
else value
)
pkgSet;
in scrubbedEval.options;
};
nixos-help = let
helpScript = pkgs.writeShellScriptBin "nixos-help" ''
# Finds first executable browser in a colon-separated list.
# (see how xdg-open defines BROWSER)
browser="$(
IFS=: ; for b in $BROWSER; do
[ -n "$(type -P "$b" || true)" ] && echo "$b" && break
done
)"
if [ -z "$browser" ]; then
browser="$(type -P xdg-open || true)"
if [ -z "$browser" ]; then
browser="${pkgs.w3m-nographics}/bin/w3m"
fi
fi
exec "$browser" ${manual.manualHTMLIndex}
'';
desktopItem = pkgs.makeDesktopItem {
name = "nixos-manual";
desktopName = "NixOS Manual";
genericName = "View NixOS documentation in a web browser";
icon = "nix-snowflake";
exec = "nixos-help";
categories = "System";
};
in pkgs.symlinkJoin {
name = "nixos-help";
paths = [
helpScript
desktopItem
];
};
in
{
imports = [
(mkRenamedOptionModule [ "programs" "info" "enable" ] [ "documentation" "info" "enable" ])
(mkRenamedOptionModule [ "programs" "man" "enable" ] [ "documentation" "man" "enable" ])
(mkRenamedOptionModule [ "services" "nixosManual" "enable" ] [ "documentation" "nixos" "enable" ])
];
options = {
documentation = {
enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to install documentation of packages from
<option>environment.systemPackages</option> into the generated system path.
See "Multiple-output packages" chapter in the nixpkgs manual for more info.
'';
# which is at ../../../doc/multiple-output.chapter.md
};
man.enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to install manual pages and the <command>man</command> command.
This also includes "man" outputs.
'';
};
man.generateCaches = mkOption {
type = types.bool;
default = false;
description = ''
Whether to generate the manual page index caches using
<literal>mandb(8)</literal>. This allows searching for a page or
keyword using utilities like <literal>apropos(1)</literal>.
'';
};
info.enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to install info pages and the <command>info</command> command.
This also includes "info" outputs.
'';
};
doc.enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to install documentation distributed in packages' <literal>/share/doc</literal>.
Usually plain text and/or HTML.
This also includes "doc" outputs.
'';
};
dev.enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to install documentation targeted at developers.
<itemizedlist>
<listitem><para>This includes man pages targeted at developers if <option>man.enable</option> is
set (this also includes "devman" outputs).</para></listitem>
<listitem><para>This includes info pages targeted at developers if <option>info.enable</option>
is set (this also includes "devinfo" outputs).</para></listitem>
<listitem><para>This includes other pages targeted at developers if <option>doc.enable</option>
is set (this also includes "devdoc" outputs).</para></listitem>
</itemizedlist>
'';
};
nixos.enable = mkOption {
type = types.bool;
default = true;
description = ''
Whether to install NixOS's own documentation.
<itemizedlist>
<listitem><para>This includes man pages like
<citerefentry><refentrytitle>configuration.nix</refentrytitle>
<manvolnum>5</manvolnum></citerefentry> if <option>man.enable</option> is
set.</para></listitem>
<listitem><para>This includes the HTML manual and the <command>nixos-help</command> command if
<option>doc.enable</option> is set.</para></listitem>
</itemizedlist>
'';
};
nixos.includeAllModules = mkOption {
type = types.bool;
default = false;
description = ''
Whether the generated NixOS's documentation should include documentation for all
the options from all the NixOS modules included in the current
<literal>configuration.nix</literal>. Disabling this will make the manual
generator to ignore options defined outside of <literal>baseModules</literal>.
'';
};
nixos.extraModuleSources = mkOption {
type = types.listOf (types.either types.path types.str);
default = [ ];
description = ''
Which extra NixOS module paths the generated NixOS's documentation should strip
from options.
'';
example = literalExample ''
# e.g. with options from modules in ''${pkgs.customModules}/nix:
[ pkgs.customModules ]
'';
};
};
};
config = mkIf cfg.enable (mkMerge [
(mkIf cfg.man.enable {
environment.systemPackages = [ pkgs.man-db ];
environment.pathsToLink = [ "/share/man" ];
environment.extraOutputsToInstall = [ "man" ] ++ optional cfg.dev.enable "devman";
environment.etc."man_db.conf".text =
let
manualPages = pkgs.buildEnv {
name = "man-paths";
paths = config.environment.systemPackages;
pathsToLink = [ "/share/man" ];
extraOutputsToInstall = ["man"];
ignoreCollisions = true;
};
manualCache = pkgs.runCommandLocal "man-cache" { }
''
echo "MANDB_MAP ${manualPages}/share/man $out" > man.conf
${pkgs.man-db}/bin/mandb -C man.conf -psc >/dev/null 2>&1
'';
in
''
# Manual pages paths for NixOS
MANPATH_MAP /run/current-system/sw/bin /run/current-system/sw/share/man
MANPATH_MAP /run/wrappers/bin /run/current-system/sw/share/man
${optionalString cfg.man.generateCaches ''
# Generated manual pages cache for NixOS (immutable)
MANDB_MAP /run/current-system/sw/share/man ${manualCache}
''}
# Manual pages caches for NixOS
MANDB_MAP /run/current-system/sw/share/man /var/cache/man/nixos
'';
})
(mkIf cfg.info.enable {
environment.systemPackages = [ pkgs.texinfoInteractive ];
environment.pathsToLink = [ "/share/info" ];
environment.extraOutputsToInstall = [ "info" ] ++ optional cfg.dev.enable "devinfo";
environment.extraSetup = ''
if [ -w $out/share/info ]; then
shopt -s nullglob
for i in $out/share/info/*.info $out/share/info/*.info.gz; do
${pkgs.buildPackages.texinfo}/bin/install-info $i $out/share/info/dir
done
fi
'';
})
(mkIf cfg.doc.enable {
environment.pathsToLink = [ "/share/doc" ];
environment.extraOutputsToInstall = [ "doc" ] ++ optional cfg.dev.enable "devdoc";
})
(mkIf cfg.nixos.enable {
system.build.manual = manual;
environment.systemPackages = []
++ optional cfg.man.enable manual.manpages
++ optionals cfg.doc.enable ([ manual.manualHTML nixos-help ]
++ optionals config.services.xserver.enable [ pkgs.nixos-icons ]);
services.getty.helpLine = mkIf cfg.doc.enable (
"\nRun 'nixos-help' for the NixOS manual."
);
})
]);
}