Python3.9.12+Alpine镜像：解决matplotlib构建wheel失败问题

错误信息 #

error: Failed to download any of the following: ['http://www.qhull.org/download/qhull-2020-src-8.0.2.tgz'].  Please download one of these urls and extract it into 'build/' at the top-level of the source repository.
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for matplotlib
Failed to build matplotlib
ERROR: Could not build wheels for matplotlib, which is required to install pyproject.toml-based projects

解决方法 #

方法一：安装系统级qhull依赖 #

Alpine的软件源中提供了qhull的开发包，安装后matplotlib编译时会直接调用系统已有的qhull，无需自行下载：

apk add --no-cache qhull-dev
pip install matplotlib

方法二：手动下载并指定qhull路径 #

如果系统包安装后仍有问题，可手动下载qhull源码并指定路径：

1. 创建临时目录：

mkdir -p /tmp/matplotlib-build/build

2. 下载qhull 2020.2版本的源码压缩包，解压到上述build目录（确保解压后的文件直接在build目录内，不要嵌套子目录）
3. 设置环境变量后安装matplotlib：

export QHULL_DIR=/tmp/matplotlib-build
pip install matplotlib

方法三：安装兼容的预编译版本 #

选择对Python3.9和Alpine兼容性更好的matplotlib版本，避免编译过程：

pip install matplotlib==3.5.3

内容的提问来源于stack exchange，提问作者Davood