Pin rosdistro version and package the script to be usable without nix develop

Now the script works without updating rosdep, i.e., fetching the
database from the Internet.

flake.lock

@@ -79,7 +79,24 @@
         "nixpkgs": [
           "nix-ros-overlay",
           "nixpkgs"
-        ]
+        ],
+        "rosdistro": "rosdistro"
+      }
+    },
+    "rosdistro": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1724605071,
+        "narHash": "sha256-Aj43AvXYn8etRXhyDc1RwJXV0g37NilmduevcYrcaZY=",
+        "owner": "ros",
+        "repo": "rosdistro",
+        "rev": "bab0a532400c16d89606a8c7fb450f26e6028745",
+        "type": "github"
+      },
+      "original": {
+        "owner": "ros",
+        "repo": "rosdistro",
+        "type": "github"
       }
     },
     "systems": {

flake.nix

@@ -3,9 +3,10 @@
   inputs.flake-utils.url = "github:numtide/flake-utils";
   inputs.nix-ros-overlay.url = "github:lopsided98/nix-ros-overlay/master";
   inputs.nixpkgs.follows = "nix-ros-overlay/nixpkgs";
+  inputs.rosdistro = { url = "github:ros/rosdistro"; flake = false; };
 
   outputs =
-    { nixpkgs, flake-utils, nix-ros-overlay, ... }:
+    { nixpkgs, flake-utils, nix-ros-overlay, ... } @ inputs:
     flake-utils.lib.eachDefaultSystem (
       system:
       let
@@ -13,6 +14,63 @@
           inherit system;
           overlays = [ nix-ros-overlay.overlays.default ];
         };
+        rosdistro = pkgs.stdenv.mkDerivation {
+          pname = "rosdistro";
+          version = inputs.rosdistro.lastModifiedDate;
+          src = inputs.rosdistro;
+          postPatch = ''
+            substituteInPlace rosdep/sources.list.d/20-default.list \
+              --replace-fail https://raw.githubusercontent.com/ros/rosdistro/master/ file://${placeholder "out"}/
+          '';
+          postInstall = ''
+            mkdir -p $out
+            cp -r * $out
+          '';
+        };
+        rosdep-unwrapped = pkgs.python3Packages.rosdep.overrideAttrs ({ postPatch ? "", ...}: {
+          postPatch = postPatch + ''
+            substituteInPlace src/rosdep2/rep3.py \
+              --replace-fail https://raw.githubusercontent.com/ros/rosdistro/master/ file://${rosdistro}/
+          '';
+        });
+        rosdep-cache = pkgs.stdenv.mkDerivation {
+          pname = "rosdep-cache";
+          version = inputs.rosdistro.lastModifiedDate;
+          nativeBuildInputs = [
+            rosdep-unwrapped
+          ];
+          ROSDEP_SOURCE_PATH = "${rosdistro}/rosdep/sources.list.d";
+          ROSDISTRO_INDEX_URL = "file://${rosdistro}/index-v4.yaml";
+          ROS_HOME = placeholder "out";
+          buildCommand = ''
+            mkdir -p $out
+            rosdep update
+          '';
+        };
+        # rosdep with offline database
+        rosdep = pkgs.python3Packages.rosdep.overrideAttrs ({ postFixup ? "", ...}: {
+          postFixup = postFixup + ''
+            wrapProgram $out/bin/rosdep --set-default ROS_HOME ${rosdep-cache}
+          '';
+        });
+        ros2nix = pkgs.python3Packages.buildPythonApplication {
+          pname = "ros2nix";
+          version = inputs.self.lastModifiedDate;
+          src = pkgs.lib.cleanSource ./.;
+          pyproject = true;
+
+          nativeBuildInputs = with pkgs.python3Packages; [
+            setuptools
+          ];
+          propagatedBuildInputs = [
+            pkgs.superflore
+            pkgs.nixfmt-rfc-style
+          ];
+          makeWrapperArgs = [
+            "--set-default ROS_HOME ${rosdep-cache}"
+            "--set-default ROSDEP_SOURCE_PATH ${rosdistro}/rosdep/sources.list.d"
+          ];
+        };
       in
       {
         devShells.default = pkgs.mkShell {
@@ -23,6 +81,12 @@
             pkgs.superflore
             pkgs.python3Packages.rosdep
           ];
+          ROSDEP_SOURCE_PATH = "${rosdistro}/rosdep/sources.list.d";
+          ROSDISTRO_INDEX_URL = "file://${rosdistro}/index-v4.yaml";
+        };
+        packages = {
+          default = ros2nix;
+          inherit rosdistro rosdep-cache rosdep ros2nix;
         };
       }
     );

pyproject.toml

@@ -0,0 +1,25 @@
+[project]
+name = "ros2nix"
+version = "0.0.1"
+authors = [
+  { name="Michal Sojka", email="wsh@2x.cz" },
+]
+description = "Convert ROS package.xml to Nix expression package.nix"
+readme = "README.md"
+requires-python = ">=3.8"
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: Apache 2",
+    "Operating System :: OS Independent",
+]
+
+[project.urls]
+Homepage = "https://github.com/wentasah/ros2nix"
+Issues = "https://github.com/wentasah/ros2nix/issues"
+
+[project.scripts]
+ros2nix = "ros2nix.ros2nix:main"
+
+[build-system]
+requires = ["setuptools>=61.0"]
+build-backend = "setuptools.build_meta"

ros2nix/ros2nix.py

@@ -12,7 +12,7 @@ from rosinstall_generator.distro import get_distro
 from superflore.PackageMetadata import PackageMetadata
 from superflore.exceptions import UnresolvedDependency
 from superflore.generators.nix.nix_package import NixPackage
-from nix_expression import NixExpression, NixLicense
+from .nix_expression import NixExpression, NixLicense
 from superflore.utils import (download_file, get_distro_condition_context,
                               get_distros, get_pkg_version, info, resolve_dep,
                               retry_on_exception, warn)
@@ -59,7 +59,7 @@ def get_output_file_name(pkg, args):
 
     return os.path.join(args.output_dir, fn)
 
-def main(args):
+def ros2nix(args):
     parser = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter)
     parser.add_argument("source", nargs="+", help="Path to package.xml") # TODO or a directory containing package.xml or an ")
 
@@ -170,7 +170,9 @@ def main(args):
             err("Failed to write derivation to disk!")
             raise e
 
+def main():
+    import sys
+    ros2nix(sys.argv[1:])
 
 if __name__ == '__main__':
-    import sys
+    main()
-    main(sys.argv[1:])