stateless-uptime-kuma/nixos/module.nix

{
  config,
  lib,
  pkgs,
  ...
}:
let
  probesFormat = pkgs.formats.json { };
  cfg = config.statelessUptimeKuma;
in
{
  options.statelessUptimeKuma = {
    build = {
      json = lib.mkOption { type = lib.types.package; };
      script = lib.mkOption { type = lib.types.package; };
    };
    enableService = lib.mkEnableOption "the auto-deployment systemd unit";
    host = lib.mkOption {
      default = null;
      type = with lib.types; nullOr str;
    };
    username = lib.mkOption {
      default = null;
      type = with lib.types; nullOr str;
    };
    passwordFile = lib.mkOption {
      type = with lib.types; nullOr path;
    };
    extraFlags = lib.mkOption {
      default = [ ];
      example = [ "--scrape-http-keywords" ];
      type = with lib.types; listOf str;
      description = lib.mdDoc ''
        Extra arguments to use for executing `stateless-uptime-kuma`.
      '';
    };
    lib = lib.mkOption { type = lib.types.raw; };
    probesConfig = {
      monitors = lib.mkOption {
        type = with lib.types; attrsOf probesFormat.type;
        default = { };
      };
      tags = lib.mkOption {
        type = with lib.types; attrsOf probesFormat.type;
        default = { };
      };
      notifications = lib.mkOption {
        type = with lib.types; attrsOf probesFormat.type;
        default = { };
      };
      status_pages = lib.mkOption {
        type = with lib.types; attrsOf probesFormat.type;
        default = { };
      };
    };
  };
  config = {
    statelessUptimeKuma = {
      lib = import ../lib { inherit lib; };
      extraFlags =
        lib.optional (cfg.host != null) "--host ${cfg.host}"
        ++ lib.optional (cfg.username != null) "--username ${cfg.username}";
      build = {
        json = probesFormat.generate "probes.json" cfg.probesConfig;
        script = pkgs.writeShellApplication {
          name = "deploy-uptime-kuma-probes";
          runtimeInputs = [ pkgs.statelessUptimeKuma ];
          text = ''
            args=("$@")
            stateless-uptime-kuma apply-json -f ${cfg.build.json} ${builtins.concatStringsSep " " cfg.extraFlags} "''${args[@]}"
          '';
        };
      };
    };
    systemd.services.stateless-uptime-kuma = lib.mkIf cfg.enableService {
      description = "Uptime-kuma probes deployment";

      wants = [ "uptime-kuma.service" ];
      after = [ "uptime-kuma.service" ];

      wantedBy = [ "multi-user.target" ];

      script = ''
        UPTIME_KUMA_PASSWORD=$(cat $CREDENTIALS_DIRECTORY/password) ${lib.getExe config.statelessUptimeKuma.build.script}
      '';

      serviceConfig = {
        LoadCredential = "password:${cfg.passwordFile}";
        Type = "oneshot";
      };
    };
  };
}