refraction/nix/module.nix
2024-04-10 01:04:07 -04:00

149 lines
3.6 KiB
Nix

self: {
config,
lib,
pkgs,
...
}: let
cfg = config.services.refraction;
defaultUser = "refraction";
inherit
(lib)
getExe
literalExpression
mdDoc
mkEnableOption
mkIf
mkOption
mkPackageOption
optionals
types
;
in {
options.services.refraction = {
enable = mkEnableOption "refraction";
package = mkPackageOption self.packages.${pkgs.stdenv.hostPlatform.system} "refraction" {};
user = mkOption {
description = mdDoc ''
User under which the service should run. If this is the default value,
the user will be created, with the specified group as the primary
group.
'';
type = types.str;
default = defaultUser;
example = literalExpression ''
"bob"
'';
};
group = mkOption {
description = mdDoc ''
Group under which the service should run. If this is the default value,
the group will be created.
'';
type = types.str;
default = defaultUser;
example = literalExpression ''
"discordbots"
'';
};
redisUrl = mkOption {
description = mdDoc ''
Connection to a redis server. If this needs to include credentials
that shouldn't be world-readable in the Nix store, set environmentFile
and override the `REDIS_URL` entry.
Pass the string `local` to setup a local Redis database.
'';
type = types.str;
default = "local";
example = literalExpression ''
"redis://localhost/"
'';
};
environmentFile = mkOption {
description = mdDoc ''
Environment file as defined in {manpage}`systemd.exec(5)`
'';
type = types.nullOr types.path;
default = null;
example = literalExpression ''
"/run/agenix.d/1/refraction"
'';
};
};
config = mkIf cfg.enable {
services.redis.servers.refraction = mkIf (cfg.redisUrl == "local") {
enable = true;
inherit (cfg) user;
port = 0; # disable tcp listener
};
systemd.services."refraction" = {
enable = true;
wantedBy = ["multi-user.target"];
after =
["network.target"]
++ optionals (cfg.redisUrl == "local") ["redis-refraction.service"];
script = ''
${getExe cfg.package}
'';
environment = {
BOT_REDIS_URL =
if cfg.redisUrl == "local"
then "unix:${config.services.redis.servers.refraction.unixSocket}"
else cfg.redisUrl;
};
serviceConfig = {
Type = "simple";
Restart = "on-failure";
EnvironmentFile = mkIf (cfg.environmentFile != null) cfg.environmentFile;
User = cfg.user;
Group = cfg.group;
# hardening
NoNewPrivileges = true;
PrivateDevices = true;
PrivateTmp = true;
PrivateUsers = true;
ProtectClock = true;
ProtectControlGroups = true;
ProtectHome = true;
ProtectHostname = true;
ProtectKernelLogs = true;
ProtectKernelModules = true;
ProtectKernelTunables = true;
ProtectSystem = "strict";
RestrictNamespaces = true;
RestrictSUIDSGID = true;
SystemCallArchitectures = "native";
SystemCallFilter = [
"@system-service"
"~@resources"
"~@privileged"
];
};
};
users = {
users = mkIf (cfg.user == defaultUser) {
${defaultUser} = {
isSystemUser = true;
inherit (cfg) group;
};
};
groups = mkIf (cfg.group == defaultUser) {
${defaultUser} = {};
};
};
};
}