linux（Centos） 安装python3 安装scrap

0.  安装顺序很重要

我们需要在linux中安装zlib-devel包，进行支持。

  我们需要在linux中安装openssl包，进行支持。

yum install python-devel

yum install openssl-devel

yum install zlib-devel

yum -y install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel

1. 安装setuptools

wget --no-check-certificate  https://pypi.python.org/packages/source/s/setuptools/setuptools-19.6.tar.gz#md5=c607dd118eae682c44ed146367a17e26

tar -zxvf setuptools-19.6.tar.gz

cd setuptools-19.6

python setup.py build

python setup.py install

2. 安装pip

wget --no-check-certificate  https://pypi.python.org/packages/source/p/pip/pip-8.0.2.tar.gz#md5=3a73c4188f8dbad6a1e6f6d44d117eeb

tar -zxvf pip-8.0.2.tar.gz

cd pip-8.0.2

python setup.py build

python setup.py install

pip install --upgrade pip

3. 安装python3

cd /root/

wget https://www.python.org/ftp/python/3.6.0/Python-3.6.0.tgz

tar -zxvf Python-3.6.0.tgz

cd Python-3.6.0

./configure

make

make install

修改系统默认的Python路径，因为在终端中输入Python命令时默认是指向Python2.6.6

mv /usr/bin/python /usr/bin/python-2

建立新的软连接，指向Python-3.6.0：

注：这里的python36是第4步指定的安装路径，python3.6是Python包里的可执行程序

ln -s /root/Python-3.6.0/python /usr/bin/python

ln -s /home/yy/Python-3.6.0/python /usr/bin/python

mv /usr/bin/python /usr/bin/python2bak

ln -s /usr/bin/python3 /usr/bin/python

4. 安装scrapy

pip install scrapy

pip install PyMySQL

pip install lxml

pip install bs4

pip install cryptography --force-reinstall

pip install UserAgent

pip install fake-useragent

pip install pywin32 针对windows的

pip install bloomfilter4py3

5.更改yum配置，因为其要用到python2才能执行，否则会导致yum不能正常使用

vi /usr/bin/yum

把#! /usr/bin/python修改为#! /usr/bin/python2

vi /usr/libexec/urlgrabber-ext-down

把#! /usr/bin/python 修改为#! /usr/bin/python2