add nix flake (#64)

* add nix flake

* add CI

Author: skykanin

.github/workflows/nix-check.yaml

@@ -0,0 +1,22 @@
+name: Nix tests
+
+on:
+  pull_request:
+    paths:
+      '**/*.nix'
+
+jobs:
+  nix-tests:
+    name: nix-tests
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out the repository
+        uses: actions/checkout@v4
+
+      - name:
+        uses: DeterminateSystems/nix-installer-action@main
+
+      - name: Test formatting of nix files
+        run: |
+          nix fmt -- -c .

.gitignore

@@ -132,3 +132,7 @@ index.pb
 .idea
 *.iml
 .vscode/
+
+# Direnv
+.envrc
+.direnv/

flake.lock

@@ -0,0 +1,35 @@
+{
+  description = "dapla-statbank-authenticator ";
+
+  inputs = {
+    flake-parts.url = "github:hercules-ci/flake-parts";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs = inputs @ {flake-parts, ...}:
+    flake-parts.lib.mkFlake {inherit inputs;} {
+      systems = ["x86_64-linux" "aarch64-linux" "aarch64-darwin" "x86_64-darwin"];
+      perSystem = {
+        config,
+        self',
+        inputs',
+        pkgs,
+        system,
+        ...
+      }: {
+        devShells.default = pkgs.mkShell {
+          name = "statbank-authenticator env";
+
+          packages = with pkgs; [
+            bump2version
+            poetry
+            python312
+            ruff-lsp
+            yaml-language-server
+          ];
+        };
+
+        formatter = pkgs.alejandra;
+      };
+    };
+}