Applying Nix best practices and useful paradigms

.envrc

@@ -0,0 +1,10 @@
+# SPDX-FileCopyrightText: 2023 Technology Innovation Institute (TII)
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# try to use flake initially, fallback to non-flake use otherwise
+if nix flake show &> /dev/null; then
+  use flake
+else
+  use nix
+fi

.gitignore

@@ -20,3 +20,5 @@ result
 /*.pdf
 /*.dot
 /*.svg
+.idea
+.direnv

LICENSES/MIT.txt

@@ -0,0 +1,9 @@
+MIT License
+
+Copyright (c) <year> <copyright holders>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

default.nix

@@ -1,31 +1,23 @@
 # SPDX-FileCopyrightText: 2023 Technology Innovation Institute (TII)
+# SPDX-FileCopyrightText: 2020-2023 Eelco Dolstra and the flake-compat contributors
 #
-# SPDX-License-Identifier: Apache-2.0
-{
-  pkgs ? import <nixpkgs> {},
-  pythonPackages ? pkgs.python3Packages,
-}:
+# SPDX-License-Identifier: MIT
+# This file originates from:
+# https://github.com/nix-community/flake-compat
+# This file provides backward compatibility to nix < 2.4 clients
+{system ? builtins.currentSystem}: let
+  lock = builtins.fromJSON (builtins.readFile ./flake.lock);
 
-pythonPackages.buildPythonPackage rec {
-  pname = "sbomnix";
-  version = pkgs.lib.removeSuffix "\n" (builtins.readFile ./VERSION);
-  format = "setuptools";
+  inherit (lock.nodes.flake-compat.locked) owner repo rev narHash;
 
-  src = ./.;
-  makeWrapperArgs = [
-    "--prefix PATH : ${pkgs.lib.makeBinPath [ pkgs.nix pkgs.graphviz ]}"
-  ];
+  flake-compat = fetchTarball {
+    url = "https://github.com/${owner}/${repo}/archive/${rev}.tar.gz";
+    sha256 = narHash;
+  };
 
-  propagatedBuildInputs = [ 
-    pkgs.reuse
-    pythonPackages.colorlog
-    pythonPackages.graphviz
-    pythonPackages.numpy
-    pythonPackages.packageurl-python
-    pythonPackages.packaging
-    pythonPackages.pandas
-    pythonPackages.requests
-    pythonPackages.tabulate
-  ];
-  pythonImportsCheck = [ "sbomnix" ];
-}
+  flake = import flake-compat {
+    inherit system;
+    src = ./.;
+  };
+in
+  flake.defaultNix

flake.nix

@@ -4,69 +4,51 @@
 {
   description = "Flakes file for sbomnix";
 
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-
-  outputs = { self, nixpkgs }:
-    let
-      systems = [ "x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" ];
-      # forEachSystem [ "x86_64-linux" ] { example = true; } -> { x86_64-linux.example = true }
-      forEachSystem = nixpkgs.lib.genAttrs systems;
-      # Imports a module expecting a system to be passed in
-      importExpectingSystem = module: system: import module {
-        pkgs = import nixpkgs { inherit system; };
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-parts.url = "github:hercules-ci/flake-parts";
+    flake-root.url = "github:srid/flake-root";
+    treefmt-nix = {
+      url = "github:numtide/treefmt-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    # For preserving compatibility with non-Flake users
+    flake-compat = {
+      url = "github:nix-community/flake-compat";
+      flake = false;
+    };
+    nix-fast-build = {
+      url = "github:Mic92/nix-fast-build";
+      # re-use some existing inputs
+      inputs = {
+        flake-parts.follows = "flake-parts";
+        treefmt-nix.follows = "treefmt-nix";
       };
-      vulnxscan = importExpectingSystem ./scripts/vulnxscan/vulnxscan.nix;
-      repology_cli = importExpectingSystem ./scripts/repology/repology_cli.nix;
-      nixupdate = importExpectingSystem ./scripts/nixupdate/nixupdate.nix;
-      sbomnix = importExpectingSystem ./default.nix;
-      sbomnix-shell = importExpectingSystem ./shell.nix;
-    in
-    {
-      # nix package
-      packages = forEachSystem (system: {
-        repology_cli = repology_cli system;
-        nixupdate = nixupdate system;
-        vulnxscan = vulnxscan system;
-        sbomnix = sbomnix system;
-        default = sbomnix system;
-      });
-
-      apps = forEachSystem (system: {
-        # nix run .#sbomnix
-        sbomnix = {
-          type = "app";
-          program = "${self.packages.${system}.sbomnix}/bin/sbomnix";
-        };
-
-        # nix run .#nixgraph
-        nixgraph = {
-          type = "app";
-          program = "${self.packages.${system}.sbomnix}/bin/nixgraph";
-        };
-
-        # nix run .#vulnxscan
-        vulnxscan = {
-          type = "app";
-          program = "${self.packages.${system}.vulnxscan}/bin/vulnxscan.py";
-        };
-
-        # nix run .#repology_cli
-        repology_cli = {
-          type = "app";
-          program = "${self.packages.${system}.repology_cli}/bin/repology_cli.py";
-        };
-
-        # nix run .#nix_outdated
-        nix_outdated = {
-          type = "app";
-          program = "${self.packages.${system}.nixupdate}/bin/nix_outdated.py";
-        };
-
-      });
+    };
+    nix-visualize = {
+      url = "github:craigmbooth/nix-visualize";
+      flake = false;
+    };
+    vulnix = {
+      url = "github:henrirosten/vulnix";
+      flake = false;
+    };
+  };
 
-      # nix develop
-      devShells = forEachSystem (system: {
-        default = sbomnix-shell system;
-      });
+  outputs = inputs @ {flake-parts, ...}:
+    flake-parts.lib.mkFlake
+    {
+      inherit inputs;
+    } {
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+
+      imports = [
+        ./nix
+      ];
     };
 }

githooks/check-commits.sh

@@ -8,6 +8,7 @@ SDIR="$(realpath "$SDIR")"
 
 TMPF="/tmp/TEMP.MSG"
 
+# shellcheck disable=SC2317
 function On_exit {
     rm -f "$TMPF"
 }