gh-actions: Parallelize wheel-building by explicitly specifying wheel…

…s to build in job matrix. (#51)

.github/workflows/build_wheels.yml

@@ -39,9 +39,9 @@ jobs:
   linters:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
 
@@ -62,32 +62,156 @@ jobs:
 
   build_wheels:
     needs: [linters]
-    name: Build wheels on ${{ matrix.os }}
-    runs-on: ${{ matrix.os }}
+    name: Build ${{ matrix.build.name }}
+    runs-on: ${{ matrix.build.os }}
     strategy:
       matrix:
-        os: [ubuntu-22.04, macos-12]
+        build:
+          # macOS builds
+          - name: cp37-macosx_x86_64
+            os: macos-12
+          - name: cp38-macosx_arm64
+            os: macos-12
+          - name: cp38-macosx_universal2
+            os: macos-12
+          - name: cp38-macosx_x86_64
+            os: macos-12
+          - name: cp39-macosx_arm64
+            os: macos-12
+          - name: cp39-macosx_universal2
+            os: macos-12
+          - name: cp39-macosx_x86_64
+            os: macos-12
+          - name: cp310-macosx_arm64
+            os: macos-12
+          - name: cp310-macosx_universal2
+            os: macos-12
+          - name: cp310-macosx_x86_64
+            os: macos-12
+          - name: cp311-macosx_arm64
+            os: macos-12
+          - name: cp311-macosx_universal2
+            os: macos-12
+          - name: cp311-macosx_x86_64
+            os: macos-12
+          - name: cp312-macosx_arm64
+            os: macos-12
+          - name: cp312-macosx_universal2
+            os: macos-12
+          - name: cp312-macosx_x86_64
+            os: macos-12
 
-    steps:
-      - uses: actions/checkout@v3
+          # Linux builds
+          - name: cp310-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp310-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp310-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp310-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp310-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp310-musllinux_x86_64
+            os: ubuntu-22.04
+          - name: cp311-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp311-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp311-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp311-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp311-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp311-musllinux_x86_64
+            os: ubuntu-22.04
+          - name: cp312-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp312-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp312-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp312-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp312-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp312-musllinux_x86_64
+            os: ubuntu-22.04
+          - name: cp37-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp37-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp37-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp37-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp37-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp37-musllinux_x86_64
+            os: ubuntu-22.04
+          - name: cp38-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp38-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp38-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp38-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp38-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp38-musllinux_x86_64
+            os: ubuntu-22.04
+          - name: cp39-manylinux_aarch64
+            os: ubuntu-22.04
+          - name: cp39-manylinux_i686
+            os: ubuntu-22.04
+          - name: cp39-manylinux_x86_64
+            os: ubuntu-22.04
+          - name: cp39-musllinux_aarch64
+            os: ubuntu-22.04
+          - name: cp39-musllinux_i686
+            os: ubuntu-22.04
+          - name: cp39-musllinux_x86_64
+            os: ubuntu-22.04
 
+    steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           submodules: recursive
 
       - name: Set up QEMU
         if: runner.os == 'Linux'
-        uses: docker/setup-qemu-action@v2
+        uses: docker/setup-qemu-action@v3
         with:
           platforms: all
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v2.16.2
+        uses: pypa/cibuildwheel@v2.17.0
         env:
-          CIBW_ARCHS_LINUX: auto aarch64
+          CIBW_BUILD: ${{ matrix.build.name }}
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
-          name: wheel-${{ matrix.os }}
+          name: wheel-${{ matrix.build.name }}
           path: ./wheelhouse/*.whl
+          retention-days: 1
+
+  combine-wheels:
+    needs: [build_wheels]
+    name: Combine wheels
+    runs-on: ubuntu-latest
+    env:
+      WHEEL_DIR: /tmp/wheels
+
+    steps:
+      - uses: actions/download-artifact@v4
+        with:
+          path: ${{env.WHEEL_DIR}}
+          merge-multiple: true
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: all-wheels
+          path: ${{env.WHEEL_DIR}}

pyproject.toml

@@ -36,6 +36,10 @@ color = true
 preview = true
 
 [tool.cibuildwheel]
+# NOTE: The wheels to be built (and skipped) must be kept in-sync with the GitHub workflow. The GH
+# workflow doesn't use pyproject.toml to determine which wheels to build, but instead uses
+# environment variables so that it can build the wheels in parallel jobs.
+
 # Use `musllinux_1_2` to support C++20 compilation
 musllinux-aarch64-image = "musllinux_1_2"
 musllinux-i686-image = "musllinux_1_2"
@@ -58,6 +62,9 @@ test-skip = [
     "*-*linux_i686",
 ]
 
+[tool.cibuildwheel.linux]
+archs = ["auto", "aarch64"]
+
 [tool.cibuildwheel.macos]
 archs = ["x86_64", "universal2", "arm64"]