nixpkgs/nixos/modules/services/matrix/mjolnir.nix
2021-11-16 19:21:33 +01:00

243 lines
8.1 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.mjolnir;
yamlConfig = {
inherit (cfg) dataPath managementRoom protectedRooms;
accessToken = "@ACCESS_TOKEN@"; # will be replaced in "generateConfig"
homeserverUrl =
if cfg.pantalaimon.enable then
"http://${cfg.pantalaimon.options.listenAddress}:${toString cfg.pantalaimon.options.listenPort}"
else
cfg.homeserverUrl;
rawHomeserverUrl = cfg.homeserverUrl;
pantalaimon = {
inherit (cfg.pantalaimon) username;
use = cfg.pantalaimon.enable;
password = "@PANTALAIMON_PASSWORD@"; # will be replaced in "generateConfig"
};
};
moduleConfigFile = pkgs.writeText "module-config.yaml" (
generators.toYAML { } (filterAttrs (_: v: v != null)
(fold recursiveUpdate { } [ yamlConfig cfg.settings ])));
# these config files will be merged one after the other to build the final config
configFiles = [
"${pkgs.mjolnir}/share/mjolnir/config/default.yaml"
moduleConfigFile
];
# this will generate the default.yaml file with all configFiles as inputs and
# replace all secret strings using replace-secret
generateConfig = pkgs.writeShellScript "mjolnir-generate-config" (
let
yqEvalStr = concatImapStringsSep " * " (pos: _: "select(fileIndex == ${toString (pos - 1)})") configFiles;
yqEvalArgs = concatStringsSep " " configFiles;
in
''
set -euo pipefail
umask 077
# mjolnir will try to load a config from "./config/default.yaml" in the working directory
# -> let's place the generated config there
mkdir -p ${cfg.dataPath}/config
# merge all config files into one, overriding settings of the previous one with the next config
# e.g. "eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' filea.yaml fileb.yaml" will merge filea.yaml with fileb.yaml
${pkgs.yq-go}/bin/yq eval-all -P '${yqEvalStr}' ${yqEvalArgs} > ${cfg.dataPath}/config/default.yaml
${optionalString (cfg.accessTokenFile != null) ''
${pkgs.replace-secret}/bin/replace-secret '@ACCESS_TOKEN@' '${cfg.accessTokenFile}' ${cfg.dataPath}/config/default.yaml
''}
${optionalString (cfg.pantalaimon.passwordFile != null) ''
${pkgs.replace-secret}/bin/replace-secret '@PANTALAIMON_PASSWORD@' '${cfg.pantalaimon.passwordFile}' ${cfg.dataPath}/config/default.yaml
''}
''
);
in
{
options.services.mjolnir = {
enable = mkEnableOption "Mjolnir, a moderation tool for Matrix";
homeserverUrl = mkOption {
type = types.str;
default = "https://matrix.org";
description = ''
Where the homeserver is located (client-server URL).
If <literal>pantalaimon.enable</literal> is <literal>true</literal>, this option will become the homeserver to which <literal>pantalaimon</literal> connects.
The listen address of <literal>pantalaimon</literal> will then become the <literal>homeserverUrl</literal> of <literal>mjolnir</literal>.
'';
};
accessTokenFile = mkOption {
type = with types; nullOr path;
default = null;
description = ''
File containing the matrix access token for the <literal>mjolnir</literal> user.
'';
};
pantalaimon = mkOption {
description = ''
<literal>pantalaimon</literal> options (enables E2E Encryption support).
This will create a <literal>pantalaimon</literal> instance with the name "mjolnir".
'';
default = { };
type = types.submodule {
options = {
enable = mkEnableOption ''
If true, accessToken is ignored and the username/password below will be
used instead. The access token of the bot will be stored in the dataPath.
'';
username = mkOption {
type = types.str;
description = "The username to login with.";
};
passwordFile = mkOption {
type = with types; nullOr path;
default = null;
description = ''
File containing the matrix password for the <literal>mjolnir</literal> user.
'';
};
options = mkOption {
type = types.submodule (import ./pantalaimon-options.nix);
default = { };
description = ''
passthrough additional options to the <literal>pantalaimon</literal> service.
'';
};
};
};
};
dataPath = mkOption {
type = types.path;
default = "/var/lib/mjolnir";
description = ''
The directory the bot should store various bits of information in.
'';
};
managementRoom = mkOption {
type = types.str;
default = "#moderators:example.org";
description = ''
The room ID where people can use the bot. The bot has no access controls, so
anyone in this room can use the bot - secure your room!
This should be a room alias or room ID - not a matrix.to URL.
Note: <literal>mjolnir</literal> is fairly verbose - expect a lot of messages from it.
'';
};
protectedRooms = mkOption {
type = types.listOf types.str;
default = [ ];
example = literalExpression ''
[
"https://matrix.to/#/#yourroom:example.org"
"https://matrix.to/#/#anotherroom:example.org"
]
'';
description = ''
A list of rooms to protect (matrix.to URLs).
'';
};
settings = mkOption {
default = { };
type = (pkgs.formats.yaml { }).type;
example = literalExpression ''
{
autojoinOnlyIfManager = true;
automaticallyRedactForReasons = [ "spam" "advertising" ];
}
'';
description = ''
Additional settings (see <link xlink:href="https://github.com/matrix-org/mjolnir/blob/main/config/default.yaml">mjolnir default config</link> for available settings). These settings will override settings made by the module config.
'';
};
};
config = mkIf config.services.mjolnir.enable {
assertions = [
{
assertion = !(cfg.pantalaimon.enable && cfg.pantalaimon.passwordFile == null);
message = "Specify pantalaimon.passwordFile";
}
{
assertion = !(cfg.pantalaimon.enable && cfg.accessTokenFile != null);
message = "Do not specify accessTokenFile when using pantalaimon";
}
{
assertion = !(!cfg.pantalaimon.enable && cfg.accessTokenFile == null);
message = "Specify accessTokenFile when not using pantalaimon";
}
];
services.pantalaimon-headless.instances."mjolnir" = mkIf cfg.pantalaimon.enable
{
homeserver = cfg.homeserverUrl;
} // cfg.pantalaimon.options;
systemd.services.mjolnir = {
description = "mjolnir - a moderation tool for Matrix";
wants = [ "network-online.target" ] ++ optionals (cfg.pantalaimon.enable) [ "pantalaimon-mjolnir.service" ];
after = [ "network-online.target" ] ++ optionals (cfg.pantalaimon.enable) [ "pantalaimon-mjolnir.service" ];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
ExecStart = ''${pkgs.mjolnir}/bin/mjolnir'';
ExecStartPre = [ generateConfig ];
WorkingDirectory = cfg.dataPath;
StateDirectory = "mjolnir";
StateDirectoryMode = "0700";
ProtectSystem = "strict";
ProtectHome = true;
PrivateTmp = true;
NoNewPrivileges = true;
PrivateDevices = true;
User = "mjolnir";
Restart = "on-failure";
/* TODO: wait for #102397 to be resolved. Then load secrets from $CREDENTIALS_DIRECTORY+"/NAME"
DynamicUser = true;
LoadCredential = [] ++
optionals (cfg.accessTokenFile != null) [
"access_token:${cfg.accessTokenFile}"
] ++
optionals (cfg.pantalaimon.passwordFile != null) [
"pantalaimon_password:${cfg.pantalaimon.passwordFile}"
];
*/
};
};
users = {
users.mjolnir = {
group = "mjolnir";
isSystemUser = true;
};
groups.mjolnir = { };
};
};
meta = {
doc = ./mjolnir.xml;
maintainers = with maintainers; [ jojosch ];
};
}