安装OpenCV失败，因为它找不到"skbuild“

Question

我有一个docker镜像，我需要在其中安装openCV，但从昨天开始它开始失败，因为它找不到"skbuild“模块：

Step 12/24 : RUN pip install opencv-python opencv-contrib-python
 ---> Running in a0f746a23aed
Collecting opencv-python
  Downloading https://files.pythonhosted.org/packages/77/f5/49f034f8d109efcf9b7e98fbc051878b83b2f02a1c73f92bbd37f317288e/opencv-python-4.4.0.42.tar.gz (88.9MB)
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-build-cciracwm/opencv-python/setup.py", line 9, in <module>
        import skbuild
    ModuleNotFoundError: No module named 'skbuild'

在主机上，我也找不到该模块，而pip search要么什么也不返回，要么返回服务器错误：

sudo pip3 search skbuild
WARNING: The directory '/home/ali/.cache/pip' or its parent directory is not owned or is not writable by the current user. The cache has been disabled. Check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
ERROR: Exception:
Traceback (most recent call last):
  File "/usr/local/lib/python3.6/dist-packages/pip/_internal/cli/base_command.py", line 216, in _main
    status = self.run(options, args)
  File "/usr/local/lib/python3.6/dist-packages/pip/_internal/commands/search.py", line 60, in run
    pypi_hits = self.search(query, options)
  File "/usr/local/lib/python3.6/dist-packages/pip/_internal/commands/search.py", line 80, in search
    hits = pypi.search({'name': query, 'summary': query}, 'or')
  File "/usr/lib/python3.6/xmlrpc/client.py", line 1112, in __call__
    return self.__send(self.__name, args)
  File "/usr/lib/python3.6/xmlrpc/client.py", line 1452, in __request
    verbose=self.__verbose
  File "/usr/local/lib/python3.6/dist-packages/pip/_internal/network/xmlrpc.py", line 45, in request
    return self.parse_response(response.raw)
  File "/usr/lib/python3.6/xmlrpc/client.py", line 1342, in parse_response
    return u.close()
  File "/usr/lib/python3.6/xmlrpc/client.py", line 656, in close
    raise Fault(**self._stack[0])
xmlrpc.client.Fault: <Fault -32403: 'server error; service unavailable'>

这是因为他们的服务器有一些问题，还是与我的pip有关？

更新

我在不同的python和pip版本上尝试过，python版本3.6和3.7，pip版本19.12、20.2.2和9.0.1 (内部图像)。

更新2

我在opencv安装之前添加了pip install scikit-build，但是我得到了另一个与cmake相关的错误：

Step 12/25 : RUN pip install scikit-build
 ---> Running in afe0c5c0fca0
Collecting scikit-build
  Downloading https://files.pythonhosted.org/packages/78/c9/7c2c7397ea64e36ebb292446896edcdecbb8c1aa6b9a1a32f6f67984c3df/scikit_build-0.11.1-py2.py3-none-any.whl (72kB)
Collecting packaging (from scikit-build)
  Downloading https://files.pythonhosted.org/packages/46/19/c5ab91b1b05cfe63cccd5cfc971db9214c6dd6ced54e33c30d5af1d2bc43/packaging-20.4-py2.py3-none-any.whl
Requirement already satisfied: wheel>=0.29.0 in /usr/lib/python3/dist-packages (from scikit-build)
Collecting distro (from scikit-build)
  Downloading https://files.pythonhosted.org/packages/25/b7/b3c4270a11414cb22c6352ebc7a83aaa3712043be29daa05018fd5a5c956/distro-1.5.0-py2.py3-none-any.whl
Requirement already satisfied: setuptools>=28.0.0; python_version >= "3" in /usr/lib/python3/dist-packages (from scikit-build)
Requirement already satisfied: six in /usr/lib/python3/dist-packages (from packaging->scikit-build)
Collecting pyparsing>=2.0.2 (from packaging->scikit-build)
  Downloading https://files.pythonhosted.org/packages/8a/bb/488841f56197b13700afd5658fc279a2025a39e22449b7cf29864669b15d/pyparsing-2.4.7-py2.py3-none-any.whl (67kB)
Installing collected packages: pyparsing, packaging, distro, scikit-build
Successfully installed distro-1.5.0 packaging-20.4 pyparsing-2.4.7 scikit-build-0.11.1
Removing intermediate container afe0c5c0fca0
 ---> 533658ddf26d
Step 13/25 : RUN pip install opencv-python opencv-contrib-python
 ---> Running in 0f2c03bc042a
Collecting opencv-python
  Downloading https://files.pythonhosted.org/packages/77/f5/49f034f8d109efcf9b7e98fbc051878b83b2f02a1c73f92bbd37f317288e/opencv-python-4.4.0.42.tar.gz (88.9MB)
Collecting opencv-contrib-python
  Downloading https://files.pythonhosted.org/packages/48/98/05bd8e00c71b66c4e7847cc051cac404191d904df58b51a7dcc3767ff747/opencv_contrib_python-4.2.0.34-cp37-cp37m-manylinux1_x86_64.whl (34.2MB)
Collecting numpy>=1.14.5 (from opencv-python)
  Downloading https://files.pythonhosted.org/packages/3d/d1/90cd7e0b27ee86d77f5386d38b74520486100286d50772377791b6ef22ff/numpy-1.19.1-cp37-cp37m-manylinux1_x86_64.whl (13.4MB)
Building wheels for collected packages: opencv-python
  Running setup.py bdist_wheel for opencv-python: started
  Running setup.py bdist_wheel for opencv-python: finished with status 'error'
  Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-w49xv99a/opencv-python/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /tmp/tmpycj03zlwpip-wheel- --python-tag cp37:
  /usr/lib/python3.7/distutils/dist.py:274: UserWarning: Unknown distribution option: 'long_description_content_type'
    warnings.warn(msg)
  Traceback (most recent call last):
    File "/usr/local/lib/python3.7/dist-packages/skbuild/setuptools_wrap.py", line 560, in setup
      cmkr = cmaker.CMaker(cmake_executable)
    File "/usr/local/lib/python3.7/dist-packages/skbuild/cmaker.py", line 95, in __init__
      self.cmake_version = get_cmake_version(self.cmake_executable)
    File "/usr/local/lib/python3.7/dist-packages/skbuild/cmaker.py", line 82, in get_cmake_version
      "Problem with the CMake installation, aborting build. CMake executable is %s" % cmake_executable)
  
  Problem with the CMake installation, aborting build. CMake executable is cmake
  
  ----------------------------------------
  Failed building wheel for opencv-python
  Running setup.py clean for opencv-python
Failed to build opencv-python
Installing collected packages: numpy, opencv-python, opencv-contrib-python
  Found existing installation: numpy 1.13.3
    Not uninstalling numpy at /usr/lib/python3/dist-packages, outside environment /usr
  Running setup.py install for opencv-python: started
    Running setup.py install for opencv-python: finished with status 'error'
    Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-w49xv99a/opencv-python/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /tmp/pip-maky1uyw-record/install-record.txt --single-version-externally-managed --compile:
    /usr/lib/python3.7/distutils/dist.py:274: UserWarning: Unknown distribution option: 'long_description_content_type'
      warnings.warn(msg)
    Traceback (most recent call last):
      File "/usr/local/lib/python3.7/dist-packages/skbuild/setuptools_wrap.py", line 560, in setup
        cmkr = cmaker.CMaker(cmake_executable)
      File "/usr/local/lib/python3.7/dist-packages/skbuild/cmaker.py", line 95, in __init__
        self.cmake_version = get_cmake_version(self.cmake_executable)
      File "/usr/local/lib/python3.7/dist-packages/skbuild/cmaker.py", line 82, in get_cmake_version
        "Problem with the CMake installation, aborting build. CMake executable is %s" % cmake_executable)
    
    Problem with the CMake installation, aborting build. CMake executable is cmake

Answer 1

如果您阅读了opencv-python package FAQ in PyPI，它清楚地为这个特定问题提供了答案:您必须运行pip install --upgrade pip。之后使用pip -V检查pip版本。

这是因为您的pip太旧，无法理解新的manylinux2014包格式，并尝试从源代码进行编译。这也会失败，因为pip太老了，无法理解如何使用pyproject.toml来安装构建依赖项，比如scikit-build。

我发现的另一个问题是你同时安装了opencv-python和opencv-contrib-python。您不应该这样做。包的PyPI页面中也对此进行了解释。你最有可能只使用opencv-contrib-python-headless包，因为你使用的是Docker，而我假设你没有使用OpenCV的图形用户界面功能。

Answer 2

只需更新pip，它就会工作。

python -m pip install --upgrade pip

Answer 3

skbuild是针对Scikit-build的。

使用pip安装它：

至于windows：pip install scikit-build

完全安装成功后：

pip install cmake