nixpkgs/nixos/modules/services/networking/haproxy.nix
2023-08-15 12:24:55 +01:00

108 lines
3.2 KiB
Nix

{ config, lib, pkgs, ... }:
let
cfg = config.services.haproxy;
haproxyCfg = pkgs.writeText "haproxy.conf" ''
global
# needed for hot-reload to work without dropping packets in multi-worker mode
stats socket /run/haproxy/haproxy.sock mode 600 expose-fd listeners level user
${cfg.config}
'';
in
with lib;
{
options = {
services.haproxy = {
enable = mkEnableOption (lib.mdDoc "HAProxy, the reliable, high performance TCP/HTTP load balancer.");
package = mkPackageOptionMD pkgs "haproxy" { };
user = mkOption {
type = types.str;
default = "haproxy";
description = lib.mdDoc "User account under which haproxy runs.";
};
group = mkOption {
type = types.str;
default = "haproxy";
description = lib.mdDoc "Group account under which haproxy runs.";
};
config = mkOption {
type = types.nullOr types.lines;
default = null;
description = lib.mdDoc ''
Contents of the HAProxy configuration file,
{file}`haproxy.conf`.
'';
};
};
};
config = mkIf cfg.enable {
assertions = [{
assertion = cfg.config != null;
message = "You must provide services.haproxy.config.";
}];
# configuration file indirection is needed to support reloading
environment.etc."haproxy.cfg".source = haproxyCfg;
systemd.services.haproxy = {
description = "HAProxy";
after = [ "network.target" ];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
User = cfg.user;
Group = cfg.group;
Type = "notify";
ExecStartPre = [
# when the master process receives USR2, it reloads itself using exec(argv[0]),
# so we create a symlink there and update it before reloading
"${pkgs.coreutils}/bin/ln -sf ${lib.getExe cfg.package} /run/haproxy/haproxy"
# when running the config test, don't be quiet so we can see what goes wrong
"/run/haproxy/haproxy -c -f ${haproxyCfg}"
];
ExecStart = "/run/haproxy/haproxy -Ws -f /etc/haproxy.cfg -p /run/haproxy/haproxy.pid";
# support reloading
ExecReload = [
"${lib.getExe cfg.package} -c -f ${haproxyCfg}"
"${pkgs.coreutils}/bin/ln -sf ${lib.getExe cfg.package} /run/haproxy/haproxy"
"${pkgs.coreutils}/bin/kill -USR2 $MAINPID"
];
KillMode = "mixed";
SuccessExitStatus = "143";
Restart = "always";
RuntimeDirectory = "haproxy";
# upstream hardening options
NoNewPrivileges = true;
ProtectHome = true;
ProtectSystem = "strict";
ProtectKernelTunables = true;
ProtectKernelModules = true;
ProtectControlGroups = true;
SystemCallFilter= "~@cpu-emulation @keyring @module @obsolete @raw-io @reboot @swap @sync";
# needed in case we bind to port < 1024
AmbientCapabilities = "CAP_NET_BIND_SERVICE";
};
};
users.users = optionalAttrs (cfg.user == "haproxy") {
haproxy = {
group = cfg.group;
isSystemUser = true;
};
};
users.groups = optionalAttrs (cfg.group == "haproxy") {
haproxy = {};
};
};
}