added nix support

flake.nix

@@ -0,0 +1,94 @@
+{
+  description = "A flake to install sTodo";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+  }: {
+    packages.x86_64-linux.sTodo = with nixpkgs.legacyPackages.x86_64-linux;
+      stdenv.mkDerivation {
+        pname = "sTodo";
+        version = "1.0.0";
+
+        src = fetchTarball {
+          url = "https://git.stuce.ch/stuce/sTodo/releases/download/Release1/release1.tar.gz";
+          sha256 = "10jyldwmcs5zyz1k8lp3jscn7nhlvn56g0709l5jp91qimw7xiqz";
+        };
+        buildInputs = [zlib gmp libffi openssl];
+        installPhase = ''
+          mkdir -p $out/bin
+          cp $src/sTodo $out/bin
+        '';
+        mainProgram = "sTodo";
+      };
+    nixosModules.sTodo = {
+      config,
+      lib,
+      ...
+    }: let
+      cfg = config.services.sTodo;
+    in {
+      options.services.sTodo = {
+        # options.programs.sTodo = {
+        enable = lib.mkEnableOption "sTodo";
+        package = lib.mkOption {
+          type = lib.types.package;
+          default = self.packages.x86_64-linux.sTodo;
+        };
+        appRoot = lib.mkOption {
+          type = lib.types.str;
+          default = "http://localhost:6901";
+          description = "Link used to access the webapp";
+        };
+
+        staticRoot = lib.mkOption {
+          type = lib.types.str;
+          default = "/etc/sTodo/static";
+          description = "Location of the static folder";
+        };
+
+        databaseFolder = lib.mkOption {
+          type = lib.types.str;
+          default = "/etc/sTodo/sTodo.sqlite3";
+          description = "Location of the database folder";
+        };
+
+        clientSessionKey = lib.mkOption {
+          type = lib.types.str;
+          default = "/etc/sTodo/client_session_key.aes";
+          description = "Location of the client session key";
+        };
+
+        port = lib.mkOption {
+          type = lib.types.int;
+          default = 6901;
+          description = "Default port of the app";
+        };
+      };
+
+      # Systemd Service
+      config = lib.mkIf cfg.enable {
+        systemd.services.sTodo = {
+          description = "Launch a sTodo app to have a online todolist";
+          after = ["network.target"];
+          wantedBy = ["multi-user.target"];
+          serviceConfig = {
+            ExecStart = "${cfg.package}/bin/sTodo";
+            Restart = "always";
+          };
+          environment = {
+            YESOD_PORT = "${toString cfg.port}";
+            YESOD_APPROOT = "${cfg.appRoot}";
+            YESOD_SQLITE_DATABASE = "${cfg.databaseFolder}";
+            YESOD_STATIC_DIR = "${cfg.staticRoot}";
+            YESOD_SESSION_KEY = "${cfg.clientSessionKey}";
+          };
+        };
+      };
+    };
+  };
+}