Add License-File field to Python package info

To follow the source layout required by PEP 639, we need to move the
licenses directory within the wheel to *.dist-info/licenses/licenses.
We also need to add COPYING.LESSER, since it's included in the sdist.
(This is a bugfix in any case, since that license governs the artifacts
in artifacts/python.)

Signed-off-by: Benjamin Gilbert <[email protected]>

Author: bgilbert

artifacts/python/meson.build

@@ -16,7 +16,7 @@ py_artifacts = [
     build_always_stale : true,
     env : env,
   ),
-  files('py.typed'),
+  files(meson.project_source_root() / 'COPYING.LESSER', 'py.typed'),
   libopenslide_postprocessed,
   licenses,
 ]

artifacts/python/pyproject.in.toml

@@ -7,6 +7,7 @@ maintainers = [
 description = "Binary build of OpenSlide"
 readme = "artifacts/python/README.md"
 license = "@spdx@"
+license-files = "@license-files@"
 keywords = ["OpenSlide", "whole-slide image", "virtual slide", "library"]
 classifiers = [
     "Development Status :: 5 - Production/Stable",

artifacts/write-wheel.py

@@ -70,8 +70,16 @@ class Args(TypedArgs):
                         whl.metadir / 'METADATA', BytesIO(meta.as_bytes())
                     )
                 )
-            elif path.name == 'licenses':
-                whl.add_tree(whl.metadir, path)
+            elif path.name in ('COPYING.LESSER', 'licenses'):
+                # Assume the file or dir is in the root of the sdist.
+                # Write licenses directory to {metadir}/licenses/licenses,
+                # as required by PEP 639.
+                if path.is_dir():
+                    whl.add_tree(whl.metadir / 'licenses', path)
+                else:
+                    whl.add(
+                        FileMember(whl.metadir / 'licenses' / path.name, fh)
+                    )
             else:
                 name = re.sub('(\\.so\\.[0-9]+)\\.[0-9.]+', '\\1', path.name)
                 whl.add(FileMember(whl.datadir / name, fh))

common/python.py

@@ -1,7 +1,7 @@
 #
 # Tools for building OpenSlide and its dependencies
 #
-# Copyright (c) 2023 Benjamin Gilbert
+# Copyright (c) 2023-2025 Benjamin Gilbert
 # All rights reserved.
 #
 # This script is free software: you can redistribute it and/or modify it
@@ -21,6 +21,8 @@
 
 from email.message import Message
 from email.policy import Compat32
+from pathlib import PurePath
+import re
 import tomllib
 
 from .meson import meson_introspect, meson_source_root
@@ -29,8 +31,30 @@
 
 def pyproject_fill_template(tmpl: str) -> str:
     version: str = meson_introspect('projectinfo')['version']
-    return tmpl.replace('@version@', version).replace(
-        '@spdx@', get_spdx(Project.get_enabled())
+    projs = Project.get_enabled()
+    license_relpaths = [PurePath('COPYING.LESSER')] + [
+        PurePath('licenses') / relpath
+        for proj in projs
+        for relpath in proj.license_relpaths
+    ]
+    for relpath in license_relpaths:
+        # we don't do proper toml assembly
+        if '"' in relpath.as_posix():
+            raise ValueError(f'Invalid license file path: {relpath}')
+    return (
+        tmpl.replace('@version@', version)
+        .replace('@spdx@', get_spdx(projs))
+        .replace(
+            '"@license-files@"',
+            '["'
+            + '", "'.join(
+                sorted(
+                    (relpath.as_posix() for relpath in license_relpaths),
+                    key=lambda s: s.lower(),
+                )
+            )
+            + '"]',
+        )
     )
 
 
@@ -71,6 +95,13 @@ def pyproject_to_message(pyproject: str) -> Message:
                 out['Maintainer-Email'] = f'{item["name"]} <{item["email"]}>'
         elif k == 'license':
             out['License-Expression'] = v
+        elif k == 'license-files':
+            for vv in v:
+                if re.search(r'\*|\?|\[|\.\.', vv):
+                    raise ValueError(
+                        f'Glob or path traversal in license file path: {vv}'
+                    )
+                out['License-File'] = vv
         elif k == 'classifiers':
             for vv in v:
                 out['Classifier'] = vv

common/software.py

@@ -28,7 +28,7 @@
 from itertools import count
 import json
 import os
-from pathlib import Path
+from pathlib import Path, PurePath
 import shlex
 import shutil
 import subprocess
@@ -235,6 +235,14 @@ def spdx(self) -> str:
         else:
             raise ValueError(f'SPDX override needed for {self.id}')
 
+    @property
+    def license_relpaths(self) -> list[PurePath]:
+        base = PurePath(self.display)
+        return [
+            base / (f(self)[0] if callable(f) else Path(f).name)
+            for f in self.license_files
+        ]
+
     def write_license_files(self, base: Path) -> None:
         dir = base / self.display
         dir.mkdir(parents=True)