chore: the nix stuff

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1783389287,
+        "narHash": "sha256-0xIy4dVLqq47rA+mRy0hXDfjhQd4E5PoIns/RmB7nR4=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0ad6f47ea4fe188f4bc8f0380f93ae8523337c6c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-26.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,42 @@
+{
+  description = "AZess - internal Active Directory user setup web application";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-26.05";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+  }: let
+    systems = [
+      "x86_64-linux"
+      "aarch64-linux"
+    ];
+    forAllSystems = nixpkgs.lib.genAttrs systems;
+  in {
+    packages = forAllSystems (system: let
+      pkgs = nixpkgs.legacyPackages.${system};
+      azess = pkgs.callPackage ./nix/package.nix {};
+    in {
+      inherit azess;
+      default = azess;
+    });
+
+    apps = forAllSystems (system: {
+      default = {
+        type = "app";
+        program = "${nixpkgs.lib.getExe self.packages.${system}.default}";
+      };
+      azess = self.apps.${system}.default;
+    });
+
+    checks = forAllSystems (system: {
+      default = self.packages.${system}.default;
+    });
+
+    formatter = forAllSystems (system: nixpkgs.legacyPackages.${system}.alejandra);
+
+    nixosModules.default = import ./nix/module.nix {inherit self;};
+  };
+}

nix/module.nix

@@ -0,0 +1,98 @@
+{self}: {
+  config,
+  lib,
+  pkgs,
+  ...
+}: let
+  cfg = config.services.azess;
+  inherit (lib) mkEnableOption mkIf mkOption types;
+
+  defaultPackage = self.packages.${pkgs.stdenv.hostPlatform.system}.default;
+  gunicornArgs =
+    [
+      "--workers"
+      (toString cfg.workers)
+      "--bind"
+      "${cfg.host}:${toString cfg.port}"
+    ]
+    ++ cfg.extraArgs;
+in {
+  options.services.azess = {
+    enable = mkEnableOption "AZess Flask/Gunicorn web application";
+
+    package = mkOption {
+      type = types.package;
+      default = defaultPackage;
+      defaultText = "self.packages.\${pkgs.stdenv.hostPlatform.system}.default";
+      description = "AZess package to run.";
+    };
+
+    host = mkOption {
+      type = types.str;
+      default = "127.0.0.1";
+      description = "Host/IP address Gunicorn binds to.";
+    };
+
+    port = mkOption {
+      type = types.port;
+      default = 8000;
+      description = "TCP port Gunicorn binds to.";
+    };
+
+    workers = mkOption {
+      type = types.ints.positive;
+      default = 4;
+      description = "Number of Gunicorn worker processes.";
+    };
+
+    openFirewall = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Open the configured TCP port in the local firewall.";
+    };
+
+    extraArgs = mkOption {
+      type = types.listOf types.str;
+      default = [];
+      description = "Additional arguments passed to Gunicorn before app:app.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    users.groups.azess = {};
+    users.users.azess = {
+      isSystemUser = true;
+      group = "azess";
+      description = "AZess service user";
+    };
+
+    systemd.services.azess = {
+      description = "AZess Active Directory user setup application";
+      wantedBy = ["multi-user.target"];
+      after = ["network.target"];
+
+      environment = {
+        XDG_CACHE_HOME = "/var/cache/azess";
+      };
+
+      serviceConfig = {
+        ExecStart = "${lib.getExe cfg.package} ${lib.escapeShellArgs gunicornArgs}";
+        Restart = "on-failure";
+        RestartSec = "5s";
+
+        User = "azess";
+        Group = "azess";
+        CacheDirectory = "azess";
+        RuntimeDirectory = "azess";
+
+        NoNewPrivileges = true;
+        PrivateTmp = true;
+        ProtectHome = true;
+        ProtectSystem = "strict";
+        RestrictAddressFamilies = ["AF_UNIX" "AF_INET" "AF_INET6"];
+      };
+    };
+
+    networking.firewall.allowedTCPPorts = mkIf cfg.openFirewall [cfg.port];
+  };
+}

nix/package.nix

@@ -0,0 +1,52 @@
+{
+  lib,
+  python3,
+  stdenvNoCC,
+}: let
+  pythonEnv = python3.withPackages (ps: [
+    ps.flask
+    ps.gunicorn
+    ps.weasyprint
+  ]);
+in
+  stdenvNoCC.mkDerivation {
+    pname = "azess";
+    version = "0.1.0";
+
+    src = lib.fileset.toSource {
+      root = ../.;
+      fileset = lib.fileset.unions [
+        ../app.py
+        ../templates
+        ../README.md
+        ../requirements.txt
+      ];
+    };
+
+    dontBuild = true;
+
+    installPhase = ''
+      runHook preInstall
+
+      mkdir -p $out/bin $out/share/azess
+      cp app.py $out/share/azess/
+      cp -r templates $out/share/azess/
+      cp README.md requirements.txt $out/share/azess/
+
+      cat > $out/bin/azess <<EOF
+      #!${stdenvNoCC.shell}
+      cd "$out/share/azess"
+      exec ${pythonEnv}/bin/gunicorn "\$@" app:app
+      EOF
+      chmod +x $out/bin/azess
+
+      runHook postInstall
+    '';
+
+    meta = {
+      description = "Internal Flask application for generating Active Directory user account PDFs";
+      homepage = "https://git.az-gruppe.com/AZ-Intec-GmbH/AZess";
+      mainProgram = "azess";
+      platforms = lib.platforms.linux;
+    };
+  }