使用setuptools_scm运行从bdist_wheel包安装的应用程序失败，并出现版本查找错误

Question

TL;DR

我正在尝试为一个使用setuptools-scm的项目创建构建的分发包。我生成了运行python setup.py sdist bdist_wheel的wheel包。我可以使用pip install ...安装.whl包。但当我尝试运行该程序时，它抛出以下错误：

Traceback (most recent call last):
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/bin/mymodule", line 5, in <module>
    from mymodule.cli import main
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/mymodule/cli.py", line 4, in <module>
    from mymodule.contexts import ContextConfig
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/mymodule/contexts/__init__.py", line 2, in <module>
    from mymodule.contexts.context_config import ContextConfig
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/mymodule/contexts/context_config.py", line 8, in <module>
    from mymodule.commons import local_config_file_path, user_config_file_path
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/mymodule/commons/__init__.py", line 19, in <module>
    version = get_version(root="../..", relative_to=__file__)
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/setuptools_scm/__init__.py", line 144, in get_version
    return _get_version(config)
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/setuptools_scm/__init__.py", line 148, in _get_version
    parsed_version = _do_parse(config)
  File "/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages/setuptools_scm/__init__.py", line 110, in _do_parse
    raise LookupError(
LookupError: setuptools-scm was unable to detect version for '/home/zobayer/Projects/opensource/staging/myproject/venv/lib64/python3.8/site-packages'.

下面是目录树的简单视图(不展开.git\)

myproject
├── .git
├── mymodule
│   ├── cli.py
│   ├── commons
│   │   ├── command.py
│   │   ├── helpers.py
│   │   └── __init__.py
│   ├── contexts
│   │   ├── context_config.py
│   │   └── __init__.py
│   ├── __init__.py
│   └── version.py
├── LICENSE
├── MANIFEST.in
├── pyproject.toml
├── README.md
├── requirements.txt
├── setup.cfg
├── setup.py
└── tox.ini

这里没有跟踪mymodule/version.py。回购是干净的和标记的。使用setuptools 49.1.0和setuptools_scm 4.1.2，我配置了以下内容：

setup.py (省略元数据字段)

setup(
    name="myproject",
    use_scm_version=True,
    setup_requires=["wheel", "setuptools-scm"],
    packages=find_packages(exclude=["docs*", "tests*"]),
    include_package_data=True,
    install_requires=install_dependencies,
)

setup.cfg

[metadata]
license_files = LICENSE

[options]
setup_requires =
    wheel==0.34.2
    setuptools_scm==4.1.2

pyproject.toml

[build-system]
requires = ["setuptools>=42", "wheel", "setuptools_scm[toml]>=3.4"]
build-backend = "setuptools.build_meta"

[tool.setuptools_scm]
write_to = "mymodule/version.py"
write_to_template = "# -*- coding: utf-8 -*-\n\n__version__ = '{version}'\n"
version_scheme = "release-branch-semver"

我想在这里指出的是，安装可以与pip install -e .一起工作，并且应用程序可以按预期运行。

我尝试在调用get_version时更新root和relative_to参数，并尝试更新use_scm_version以使用配置字典，但都无济于事。我在github中调查了官方问题，但我无法解决这个问题。在这一点上，我确信我误解了setuptools_scm，并且可能对它进行了错误的配置。

Answer 1

您不应该在实际代码中使用setuptools-scm，它只用于打包。它寻找一个VCS存储库，从它的元数据(git标签等)中读取版本，所以很明显，当安装包时，它将失败。如果您正在尝试获取已安装包的版本，请使用importlib.metadata (从3.8开始是标准库的一部分，对于较旧的版本有一个后端口：importlib-metadata)。示例：

>>> from importlib.metadata import version
>>> version('myproject')
'0.0.1'

您也可以使用pkg_resources (setuptools的一部分)来查询版本的元数据，但请注意，它现在已被importlib.metadata取代：

>>> import pkg_resources
>>> pkg_resources.get_distribution('myproject').version
'0.0.1'