Mac OS X安装 Scrapy、PIL、BeautifulSoup

文／贰拾贰画生（简书作者）
原文链接：http://www.jianshu.com/p/5265b76026d9
著作权归作者所有，转载请联系作者获得授权，并标注“简书作者”。

环境：Mac OS X Yosemite 10.10.3

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安装Scrapy

学习Python爬虫必须要使用的框架Scrapy，话不多说。

打开终端执行命令：

sudo easy_install pip

pip 和 easy_install 都是 Python 的框架管理命令，pip 是对 easy_install的升级。

然后终端执行命令安装 Scrapy：

sudo pip install Scrapy

如果执行成功，那么 Scrapy 就安装成功了，但往往事与愿违，你很有可能遇到如下错误：

    /private/tmp/pip-build-9RYtLC/lxml/src/lxml/includes/etree_defs.h:14:10: fatal error: 'libxml/xmlversion.h' file not found
    #include "libxml/xmlversion.h"
    ^
    1 error generated.
    error: command 'cc' failed with exit status 1

    ----------------------------------------

    Command "/usr/bin/python -c "import setuptools,     tokenize;__file__='/private/tmp/pip-build-9RYtLC/lxml/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-544HZx-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /private/tmp/pip-build-9RYtLC/lxml

屏幕快照 2015-04-21 下午1.30.42.png

解决方法有如下几种：

1、终端执行命令安装或更新命令行开发工具：

xcode-select --install

2、配置路径：C_INCLUDE_PATH

C_INCLUDE_PATH=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/libxml2:/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/libxml2/libxml:/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include

3、参照官网使用如下命令安装Scrapy

STATIC_DEPS=true pip install lxml

一般此三个方法就可解决错误成功安装Scrapy，如果还是失败，参考 StackOverflow上的一个帖子

-------------------------------------------------分割线---------------------

http://stackoverflow.com/questions/30964836/scrapy-throws-importerror-cannot-import-name-xmlrpc-client

由于以上三种都不适用于我的情况。 

当我输入 scrapy的时候，

没有预期的显示出版本号，而是显示如下：

Traceback (most recent call last):
File "/usr/local/bin/scrapy", line 7, in <module>
from scrapy.cmdline import execute
File "/Library/Python/2.7/site-packages/scrapy/__init__.py", line 48,  
in <module>
from scrapy.spiders import Spider
File "/Library/Python/2.7/site-packages/scrapy/spiders/__init__.py",    
line 10, in <module>
from scrapy.http import Request
File "/Library/Python/2.7/site-packages/scrapy/http/__init__.py", line   
12, in <module>
from scrapy.http.request.rpc import XmlRpcRequest
File "/Library/Python/2.7/site-packages/scrapy/http/request/rpc.py",  
line 7, in <module>
from six.moves import xmlrpc_client as xmlrpclib
ImportError: cannot import name xmlrpc_client

突然想起来在pip安装的时候，好像six什么的 就没有安装成功。

所以，

sudo rm -rf /Library/Python/2.7/site-packages/six*
sudo rm -rf /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six*
sudo pip install six

移除后重新安装，it works.

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安装PIL

PIL是Python的图形处理库，在学习爬虫的时候可以用来处理验证码。
终端输入命令：

sudo pip install pil

恩，出错：

/Library/Python/2.7/site-packages/pip-6.1.1-py2.7.egg/pip/_vendor/requests/packages/urllib3/util/ssl_.py:79: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
  Could not find a version that satisfies the requirement pil (from versions: )
  Some externally hosted files were ignored as access to them may be unreliable (use --allow-external pil to allow).
  No matching distribution found for pil

不过提示了添加参数 --allow-external pil
好，改一下命令重新执行：

sudo pip install PIL --allow-external PIL

好的，开始安装了，哎？好像又出错了！！！

_imagingft.c:73:10: fatal error: 'freetype/fterrors.h' file not found
#include <freetype/fterrors.h>
         ^
1 error generated.
error: Setup script exited with error: command 'cc' failed with exit status 1

提示没找到 freetype/fterrors.h文件，百度怎么解决，很多文章的解决办法是执行命令：ln -s /usr/local/include/freetype2 /usr/local/include/freetype

然后，试了，不行。

从Finder来到目录 usr/local/include下，咦？好像有目录freetype2，但是么有freetype，那么...可以复制一个freetype2的副本再改名freetype不行吗？恩，然后我就这样干了。然后在终端重新执行安装PIL的命令：

sudo pip install PIL --allow-external PIL

然后就安装成功了~~

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安装BeautifulSoup

首先，官网下载最新的包beautifulsoup4 4.3.2，然后解压缩，从终端进入该目录。
终端执行

sudo python setup.py install

屏幕快照 2015-05-23 下午5.26.37.png

好，安装成功。

Beautifulsoup的官方文档

------------------spilt line -------

sudo pip install bs4

it also works.

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补充：
easy_install使用方法：

安装：easy_install PackageName
删除：easy_install -m PackageName
更新：easy_install -U PackageName

pip使用方法：

安装：pip install PackageName
删除：pip uninstall PackageName
更新：pip install -U PackageName
搜索：pip search PackageName