nix-config/modules/nixos/duckdns.nix

78 lines
2.7 KiB
Nix

{
inputs,
config,
pkgs,
lib,
...
}: let
cfg = config.services.duckdns;
urlFile = pkgs.writeText "curlurl" "url=https://www.duckdns.org/update?domains=@domains_placeholder@&token=@token_placeholder@&ip=";
in {
# partially taken from https://github.com/NixOS/nixpkgs/pull/294489
options = {
services.duckdns = {
enable = lib.mkEnableOption "Enable duckdns updating";
tokenFile = lib.mkOption {
default = null;
type = lib.types.path;
description = ''
The path to a file containing the token
used to authenticate with DuckDNS.
'';
};
domains = lib.mkOption {
type = lib.types.nullOr (lib.types.listOf lib.types.str);
example = ["examplehost"];
description = lib.mdDoc ''
The record(s) to update in DuckDNS
(without the .duckdns.org prefix)
'';
};
domainsFile = lib.mkOption {
default = null;
type = lib.types.nullOr lib.types.path;
description = ''
The path to a file containing a
newline-separated list of DuckDNS
domain(s) to be updated
'';
};
};
};
assertions = [
{
assertion = cfg.domains != null || cfg.domainsFile != null;
message = "services.duckdns.domains or services.duckdns.domainsFile has to be defined";
}
];
config = lib.mkIf cfg.enable {
systemd.services.duckdns = {
description = "DuckDNS Dynamic DNS Client";
after = ["network.target"];
wantedBy = ["multi-user.target"];
# every 5 minutes
startAt = "*:00/5:00";
serviceConfig = {
Type = "simple";
DynamicUser = true;
RuntimeDirectory = "duckdns-update";
RuntimeDirectoryMode = "700";
};
script = ''
install --mode 600 ${urlFile} $RUNTIME_DIRECTORY/curlurl
# replace the token
${pkgs.replace-secret}/bin/replace-secret @token_placeholder@ ${cfg.tokenFile} $RUNTIME_DIRECTORY/curlurl
# initalise the replacement file for the domains from the domains file if it exists, otherwise make it empty.
install --mode 600 ${if (cfg.domainsFile != null) then cfg.domainsFile else "/dev/null"} $RUNTIME_DIRECTORY/domains
# these are already in the nix store, so doesnt matter if they leak via cmdline.
echo '${lib.strings.concatStringsSep "\n" cfg.domains}' >> $RUNTIME_DIRECTORY/domains
${pkgs.gnused}/bin/sed -zi 's/\n/,/g' $RUNTIME_DIRECTORY/domains
${pkgs.replace-secret}/bin/replace-secret @domains_placeholder@ $RUNTIME_DIRECTORY/domains $RUNTIME_DIRECTORY/curlurl
${pkgs.curl}/bin/curl --no-progress-meter --insecure --config $RUNTIME_DIRECTORY/curlurl | ${pkgs.gnugrep}/bin/grep -v "KO"
'';
};
};
}