Cythonize函数生成扩展含根目录致Wheel结构异常求助

Looks like the issue comes from misaligned path configurations between setuptools and cythonize—by default, Cython preserves the relative directory structure of your .pyx files, and without telling setuptools where your actual package lives, it ends up packing the entire _src directory into the wheel. Here's how to fix it:

1. Update Your setup.py with Correct Path Mappings #

You need to explicitly tell setuptools that your package lives under the _src directory, and adjust the Cython configuration to generate extensions under the right package namespace. Here's a revised setup script:

from setuptools import setup, find_packages
from Cython.Build import cythonize

setup(
    name="your-package-name",
    version="0.1.0",
    # Map the root package namespace to our _src directory
    package_dir={"": "_src"},
    # Auto-discover all packages inside _src (avoids manual listing)
    packages=find_packages(where="_src"),
    # Cythonize the .pyx files with proper path handling
    ext_modules=cythonize(
        # Target the .pyx files directly in _src/mylib
        "_src/mylib/**/*.pyx",
        # Ensure compatibility with Python 3
        compiler_directives={"language_level": "3"},
        # Optional: Force recompile if you make changes to .pyx files
        force=True
    ),
    # Make sure regular .py files in mylib are included too
    package_data={
        "mylib": ["*.py"],
    },
)

2. Key Configuration Breakdown #

• package_dir={"": "_src"}: This tells setuptools that all your packages are rooted in the _src directory. So when it looks for the mylib package, it knows to check _src/mylib instead of the project root.
• find_packages(where="_src"): Scans _src for all valid Python packages (directories with __init__.py) and includes them in the build—no need to list each package manually.
• cythonize("_src/mylib/**/*.pyx"): By targeting the .pyx files directly in their source location, and pairing this with package_dir, Cython will generate extension modules that belong to the mylib namespace, not the _src.mylib namespace.
• package_data: Ensures that any regular .py files in mylib are included in the wheel, so you don't lose non-Cythonized code.

3. Verify the Fixed Wheel Structure #

Run your build command again:

python setup.py build_ext bdist_wheel clean --all

To check the structure, unpack the generated wheel using:

wheel unpack your-package-name-0.1.0-py3-none-any.whl

You should now see the correct, flat structure:

your-package-name-0.1.0/
└── mylib/
    ├── __init__.py
    ├── module.cpython-xxxx.so  # Compiled Cython module (extension varies by OS)
    └── [other .py files]

4. Extra Tips #

• Double-check that _src/mylib/__init__.py is properly configured (e.g., exporting modules you want users to access).
• If your Cython modules depend on external C libraries, you may need to add include_dirs to the ext_modules setup, but that's unrelated to the directory structure issue.
• Using a recent version of setuptools (>=61.0.0) helps with more reliable package path handling.

内容的提问来源于stack exchange，提问作者SuperGeo