Mac OS下Python的pycurl模块安装

玩的Python爬虫的小伙伴们一般知道pycurl模块，但是在MACOS下安装这个模块，可真不是一般的折腾啊〜啊〜啊〜

操作系统版本：macOS Mojave 10.14.6

一、缓缓入坑

sudo pip install pycurl --user

安装结束，但是在运行的时候报错来啦：

ImportError: pycurl: libcurl link-time ssl backend (openssl) is different from compile-time ssl backend (none/other)

这是由于新版的Mac系统中使用的SSL版本和之前的不一样了，针对的OpenSSL的漏洞苹果方面进行了升级，现在系统默认使用的是LibreSSL而不是OpenSSL的。按照网上各方坑友们的操作指导建议下先手动安装OpenSSL的

1. 如果没有安装brew，那就先安装吧:

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

    2.安装OpenSSL：brew install openssl，安装完它会提示你这些：

openssl is keg-only, which means it was not symlinked into /usr/local,because Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries.If you need to have openssl first in your PATH run:  echo 'export PATH="/usr/local/opt/openssl/bin:$PATH"' >> ~/.bash_profileFor compilers to find openssl you may need to set:  export LDFLAGS="-L/usr/local/opt/openssl/lib"  export CPPFLAGS="-I/usr/local/opt/openssl/include"==> Summary?  /usr/local/Cellar/openssl/1.0.2s: 1,795 files, 12.0MB

    3.安装完的OpenSSL后，再来试一波：

export LDFLAGS="-L/usr/local/opt/openssl/lib"export CPPFLAGS="-I/usr/local/opt/openssl/include"export PYCURL_SSL_LIBRARY=opensslsudo pip install pycurl --with-openssl --compile --user

安装过程依然没报错，但是...运行依然：

ImportError: pycurl: libcurl link-time ssl backend (openssl) is different from compile-time ssl backend (none/other)

总不能把curl也重新安装吧...要不试试？试试就试试：brew install curl

安装完再来一遍......还是报错！

 

二、尝试出​​坑

这次选择源码安装：从官网下载，或者GitHub的上下载

官网下载：

curl -O https://files.pythonhosted.org/packages/ac/b3/0f3979633b7890bab6098d84c84467030b807a1e2b31f5d30103af5a71ca/pycurl-7.43.0.3.tar.gz

解压：

tar zxvf pycurl-7.43.0.3.tar.gzcd pycurl-7.43.0.3

慢着！这源码编译需要啥特殊的参数呢？直接python setup.py安装可行吗？为了避免再走无谓的弯路，我决定好好研究一下：

1.先看看源码安装的参数选项：

python setup.py --helpPycURL Unix options: --curl-config=/path/to/curl-config  use specified curl-config binary --libcurl-dll=[/path/to/]libcurl.so obtain SSL library from libcurl.so --openssl-dir=/path/to/openssl/dir  path to OpenSSL headers and libraries --with-openssl                      libcurl is linked against OpenSSL --with-ssl                          legacy alias for --with-openssl --with-gnutls                       libcurl is linked against GnuTLS --with-nss                          libcurl is linked against NSS --with-mbedtls                      libcurl is linked against mbedTLSCommon commands: (see '--help-commands' for more)  setup.py build      will build the package underneath 'build/'  setup.py install    will install the packageGlobal options:  --verbose (-v)      run verbosely (default)  --quiet (-q)        run quietly (turns verbosity off)  --dry-run (-n)      don't actually do anything  --help (-h)         show detailed help message  --no-user-cfg       ignore pydistutils.cfg in your home directory  --command-packages  list of packages that provide distutils commandsInformation display options (just display information, ignore any commands)  --help-commands     list all available commands  --name              print package name  --version (-V)      print package version  --fullname          print <package name>-<version>  --author            print the author's name  --author-email      print the author's email address  --maintainer        print the maintainer's name  --maintainer-email  print the maintainer's email address  --contact           print the maintainer's name if known, else the author's  --contact-email     print the maintainer's email address if known, else the                      author's  --url               print the URL for this package  --license           print the license of the package  --licence           alias for --license  --description       print the package description  --long-description  print the long package description  --platforms         print the list of platforms  --classifiers       print the list of classifiers  --keywords          print the list of keywords  --provides          print the list of packages/modules provided  --requires          print the list of packages/modules required  --obsoletes         print the list of packages/modules made obsoleteusage: setup.py [global_opts] cmd1 [cmd1_opts] [cmd2 [cmd2_opts] ...]   or: setup.py --help [cmd1 cmd2 ...]   or: setup.py --help-commands   or: setup.py cmd --help

2.找到官网的文档中一段很有用的文字

PycURL requires that the SSL library that it is built against is the same one libcurl, and therefore PycURL, uses at runtime. PycURL’s setup.py uses curl-config to attempt to figure out which SSL library libcurl was compiled against, however this does not always work.

意思就是说PycURL要求它构建的SSL库与libcurl的相同，一般使用curl-config来试图找出哪些SSL库的libcurl中被一起编译，但是这并不总是有效的。

3.先试一波

sudo python setup.py --curl-config=/usr/bin/curl-config install --user>>> import pycurlTraceback (most recent call last):  File "<stdin>", line 1, in <module>ImportError: pycurl: libcurl link-time ssl backend (openssl) is different from compile-time ssl backend (none/other)

果然，不是“总是有效的”，官网要不那么靠谱啊。

4.看样子还要点其他的参数，这时候关于ssl的就剩下with-openssl了（--with-ssl是别名，效果一样），试一下？

sudo python setup.py --curl-config=/usr/bin/curl-config --openssl-dir=/usr/local/Cellar/openssl/1.0.2s --with-openssl install --user>>> import pycurl>>> pycurl.version'PycURL/7.43.0.3 libcurl/7.54.0 LibreSSL/2.6.5 zlib/1.2.11 nghttp2/1.24.1'

        欧耶！出坑啦！但是〜是不是看到了很奇怪的东西，是的，明明参数指定的是OpenSSL，但是编译成功后的版本信息中查到的却是“ LibreSSL ”，而不是“OpenSSL” ，是不是很奇怪？是啊，我也觉得奇怪，如果有人知道的话，请与我分享一下吧！

        这次的坑还挺深的，从网上看遇到这类的朋友不少，也有成功的样例，但是解决方案没有适合我这次的安装场景，毕竟有时候官网提供的方案都不能“总是有效”的呢！比较幸运，终于搞定了，现在这个安装步骤也是一种解决方案啦，欢迎大家试用！请记住这组命令，希望能够帮到你：

sudo python setup.py --curl-config=/usr/bin/curl-config --openssl-dir=/usr/local/Cellar/openssl/1.0.2s --with-openssl install --user

官方安装参考文档

https://pypi.org/project/pycurl/7.43.0.3/

http://pycurl.io/docs/latest/install.html#pip-and-cached-pycurl-package