WIP

.github/ISSUE_TEMPLATE/python-bump.md

@@ -1,20 +1,11 @@
-# Adding wheels for a new Python release
+# Adding a new Python release
 
 - Update Git main
   - [ ] `git checkout main`
-  - [ ] Add classifier for new Python version to `setup.py`
+  - [ ] Add classifier for new Python version to `pyproject.toml'
   - [ ] Add new Python version to lists in `.github/workflows/python.yml`
   - [ ] Commit and open a PR
   - [ ] Merge the PR when CI passes
   - [ ] Add new Python jobs to [branch protection required checks](https://github.com/openslide/openslide-python/settings/branches)
-- Build new wheels
-  - [ ] Check out a new branch from the most recent release tag
-  - [ ] Add new Python version to lists in `.github/workflows/python.yml`, commit, and open a DNM PR
-  - [ ] Find the [workflow run](https://github.com/openslide/openslide-python/actions) for the PR; download its wheels artifact
-  - [ ] Close the PR
-- [ ] In OpenSlide Python checkout, `git checkout v<version> && git clean -dxf && mkdir dist`
-- [ ] Copy downloaded wheels _from new Python release only_ into `dist` directory
-- [ ] `twine upload dist/*`
-- [ ] Upload new wheels to [GitHub release](https://github.com/openslide/openslide-python/releases)
 - [ ] Update MacPorts package
 - [ ] Update website: Python 3 versions in `download/index.md`

.github/workflows/python.yml

@@ -32,19 +32,47 @@ jobs:
         os: [ubuntu-latest, macos-latest]
         python-version: [3.8, 3.9, "3.10", "3.11", "3.12"]
         include:
+          - os: ubuntu-latest
+            python-version: 3.8
+            # can't use abi3
+            wheel: wheel
+          - os: ubuntu-latest
+            python-version: 3.9
+            # can't use abi3
+            wheel: wheel
+          - os: ubuntu-latest
+            python-version: "3.10"
+            # can't use abi3
+            wheel: wheel
+          - os: ubuntu-latest
+            python-version: "3.11"
+            # oldest supported release that can use abi3
+            wheel: wheel
           - os: ubuntu-latest
             python-version: "3.12"
             sdist: sdist
+          - os: macos-latest
+            python-version: "3.8"
+            # can't use abi3
+            wheel: wheel
           # Python 3.8 is too old to support universal binaries, and
           # setup-python's Python 3.9 and 3.10 won't build them.  Use the
           # last upstream patch releases that ship with installers.
           # https://github.com/actions/setup-python/issues/439#issuecomment-1247646682
           - os: macos-latest
             python-version: "3.9"
             upstream-python: 3.9.13
+            # can't use abi3
+            wheel: wheel
           - os: macos-latest
             python-version: "3.10"
             upstream-python: 3.10.11
+            # can't use abi3
+            wheel: wheel
+          - os: macos-latest
+            python-version: "3.11"
+            # oldest supported release that can use abi3
+            wheel: wheel
     steps:
     - name: Check out repo
       uses: actions/checkout@v4
@@ -113,6 +141,7 @@ jobs:
     - name: Tile slide
       run: python examples/deepzoom/deepzoom_tile.py --viewer -o tiled tests/fixtures/small.svs
     - name: Archive wheel
+      if: matrix.wheel
       uses: actions/upload-artifact@v3
       with:
         name: ${{ env.basename }}
@@ -129,6 +158,19 @@ jobs:
     strategy:
       matrix:
         python-version: [3.8, 3.9, "3.10", "3.11", "3.12"]
+        include:
+          - python-version: 3.8
+            # can't use abi3
+            wheel: wheel
+          - python-version: 3.9
+            # can't use abi3
+            wheel: wheel
+          - python-version: 3.10
+            # can't use abi3
+            wheel: wheel
+          - python-version: 3.11
+            # oldest supported release that can use abi3
+            wheel: wheel
     steps:
     - name: Check out repo
       uses: actions/checkout@v4
@@ -170,6 +212,7 @@ jobs:
       # Reads OPENSLIDE_PATH
       run: python examples/deepzoom/deepzoom_tile.py --viewer -o tiled tests/fixtures/small.svs
     - name: Archive wheel
+      if: matrix.wheel
       uses: actions/upload-artifact@v3
       with:
         name: ${{ env.basename }}

setup.py

@@ -1,7 +1,22 @@
+import sys
+
 from setuptools import Extension, setup
 
+# use the limited API on newer Python; build release-specific wheels on
+# older Python
+_use_limited = sys.version_info >= (3, 11)
+
 setup(
     ext_modules=[
-        Extension('openslide._convert', ['openslide/_convert.c']),
+        Extension(
+            'openslide._convert',
+            ['openslide/_convert.c'],
+            # hide symbols that aren't part of the Limited API
+            define_macros=[('Py_LIMITED_API', '0x030B0000')] if _use_limited else [],
+            # set extension module ABI tag
+            py_limited_api=_use_limited,
+        ),
     ],
+    # set wheel ABI tag
+    options={"bdist_wheel": {"py_limited_api": "cp311"}} if _use_limited else {},
 )