使用 python c-api 的 Python3 重载项目

Question

我有一个项目，我为它构建了一个 C 类（python c-api），我在 python 项目中扩展了更多。该项目的目的是为 C 库提供一个测试框架。测试主要针对C库的每个pull request执行。

项目需要从Nexus服务器下载C库的相关构建，编译依赖于C库的python类，然后进行测试。

问题：在编译 C 代码后导入/重新加载项目模块。

问题：在我看来，在依赖于 C 库的每个函数中进行导入并不是那么优雅，所以我试图调用 reload，但它似乎不起作用，或者至少不像我期望的那样。

代码为了说明问题，代码超级简化，您可以查看此线程历史记录以查看之前的代码。

main.py

from utils.my_custom_py import MyCustomExtended
from importlib.util import find_spec
from importlib import reload
from os import system, stat
import weakref
import sys


def setup():
    if system('./setup.py clean build install') > 0:
        raise SystemError("Failed to setup python c-api extention class")


def main():
    if find_spec('custom2') is None:
        setup()
        for module_name in list(sys.modules.keys()):
            m = sys.modules.get(module_name)
            if not hasattr(m, '__file__'):
                continue
            if getattr(m, '__name__', None) in [None, '__mp_main__', '__main__']:
                continue

            try:
                # superreload(m)  # from ==> IPython.extensions
                # sys.modules[module_name] = reload(m)
                reload(m)
            except Exception as e:
                ...

    MyCustomExtended(1, 2, 3)
    print("COOL")


if __name__ == "__main__":
    main()

utils.my_custom_py.py

from importlib.util import find_spec

if find_spec('custom2'):
    import custom2
else:
    class custom2:
        class Custom:
            ...

class MyCustomExtended(custom2.Custom):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

setup.py

from distutils.core import Extension, setup

custom_ext = Extension("custom2", ["src/custom.c"])
setup(name="custom2", version="1.0", ext_modules=[custom_ext])

src.custom.c取自：docs.python.org

错误输出：

running clean
running build
running build_ext
building 'custom2' extension
creating build
creating build/temp.linux-x86_64-3.6
creating build/temp.linux-x86_64-3.6/src
x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -I/tmp/PlayAround/.venv/include -I/usr/include/python3.6m -c src/custom.c -o build/temp.linux-x86_64-3.6/src/custom.o
creating build/lib.linux-x86_64-3.6
x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-Bsymbolic-functions -Wl,-z,relro -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 build/temp.linux-x86_64-3.6/src/custom.o -o build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so
running install
running install_lib
copying build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so -> /tmp/PlayAround/.venv/lib/python3.6/site-packages
running install_egg_info
Removing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
Writing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
Traceback (most recent call last):
  File "./main.py", line 38, in <module>
    main()
  File "./main.py", line 33, in main
    MyCustomExtended(1, 2, 3)
  File "/tmp/PlayAround/utils/my_custom_py.py", line 12, in __init__
    super().__init__(*args, **kwargs)
TypeError: object.__init__() takes no parameters

---

主要工作：

running clean
running build
running build_ext
building 'custom2' extension
creating build
creating build/temp.linux-x86_64-3.6
creating build/temp.linux-x86_64-3.6/src
x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -I/tmp/PlayAround/.venv/include -I/usr/include/python3.6m -c src/custom.c -o build/temp.linux-x86_64-3.6/src/custom.o
creating build/lib.linux-x86_64-3.6
x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-Bsymbolic-functions -Wl,-z,relro -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 build/temp.linux-x86_64-3.6/src/custom.o -o build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so
running install
running install_lib
copying build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so -> /tmp/PlayAround/.venv/lib/python3.6/site-packages
running install_egg_info
Removing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
Writing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
Traceback (most recent call last):
  File "./main.py", line 38, in <module>
    main()
  File "./main.py", line 33, in main
    MyCustomExtended(1, 2, 3)
  File "/tmp/PlayAround/utils/my_custom_py.py", line 12, in __init__
    super().__init__(*args, **kwargs)
TypeError: object.__init__() takes no parameters

Answer 1

最后，我通过反复试验找到了解决方案。对于此示例，代码 id 执行了以下操作：

from utils.my_custom_py import MyCustomExtended
from importlib.util import find_spec
from importlib import reload
from sys import modules
from os import system


def setup():
    if system('./setup.py clean build install') > 0:
        raise SystemError("Failed to setup python c-api extention class")

def reload_my_libs():
    global MyCustomExtended
    reload(modules['utils'])
    reload(modules['utils.my_custom_py'])
    from utils.my_custom_py import MyCustomExtended


def main():
    if find_spec('custom2') is None:
        setup()
        reload_my_libs()

    MyCustomExtended(1, 2, 3)
    print("COOL")


if __name__ == "__main__":
    main()

结果，我得到：

running clean
running build
running build_ext
building 'custom2' extension
creating build
creating build/temp.linux-x86_64-3.6
creating build/temp.linux-x86_64-3.6/src
x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -I/tmp/PlayAround/.venv/include -I/usr/include/python3.6m -c src/custom.c -o build/temp.linux-x86_64-3.6/src/custom.o
creating build/lib.linux-x86_64-3.6
x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-Bsymbolic-functions -Wl,-z,relro -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 build/temp.linux-x86_64-3.6/src/custom.o -o build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so
running install
running install_lib
copying build/lib.linux-x86_64-3.6/custom2.cpython-36m-x86_64-linux-gnu.so -> /tmp/PlayAround/.venv/lib/python3.6/site-packages
running install_egg_info
Removing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
Writing /tmp/PlayAround/.venv/lib/python3.6/site-packages/custom2-1.0.egg-info
COOL

它也适用于我之前的问题版本，该版本要复杂得多。

无论如何，感谢您的努力帮助:)