1.virtualenv
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virtualenv作用：在一个操作系统下使用不同的python环境，包括不同的python版本和不同的python库包
安装pip
[root@sht-sgmhadoopcm-01 software]# wgethttps://bootstrap.pypa.io/get-pip.py --no-check-certificate
[root@sht-sgmhadoopcm-01 software]# python get-pip.py
安装virtualenv
[root@sht-sgmhadoopcm-01 software]# pip install virtualenv
创建虚拟环境test1_env
默认新建的虚拟环境包括pip、easy_install等工具
[root@sht-sgmhadoopcm-01 software]# virtualenv test1_env
New python executable in /opt/software/test1_env/bin/python
Installing setuptools, pip, wheel...
done.
会生成响应的目录和文件
[root@sht-sgmhadoopcm-01 software]# ls -lh test1_env/
total 0
drwxr-xr-x 2 root root 268 Feb 12 17:30 bin
drwxr-xr-x 3 root root 23 Feb 12 17:30 include
drwxr-xr-x 3 root root 23 Feb 12 17:30 lib
lrwxrwxrwx 1 root root 3 Feb 12 17:30 lib64 -> lib
启用虚拟环境
这个环境下执行python相关的操作都是限定在虚拟环境中
[root@sht-sgmhadoopcm-01 software]# source test1_env/bin/activate
(test1_env) [root@sht-sgmhadoopcm-01 software]#
查看当前虚拟环境的python目录是否正确
>>> import sys
>>> print sys.path
['', '/opt/software/test1_env/lib64/python27.zip', '/opt/software/test1_env/lib64/python2.7', '/opt/software/test1_env/lib64/python2.7/plat-linux2', '/opt/software/test1_env/lib64/python2.7/lib-tk', '/opt/software/test1_env/lib64/python2.7/lib-old', '/opt/software/test1_env/lib64/python2.7/lib-dynload', '/usr/lib64/python2.7', '/usr/lib/python2.7', '/opt/software/test1_env/lib/python2.7/site-packages']
退出虚拟环境
(test1_env) [root@sht-sgmhadoopcm-01 bin]# deactivate
测试1：在系统环境中安装第三方库，虚拟环境没有影响
[root@sht-sgmhadoopcm-01 software]# pip install jinja2
[root@sht-sgmhadoopcm-01 software]# pip list|grep Jinja2
Jinja2
[root@sht-sgmhadoopcm-01 software]# source test1_env/bin/activate
(test1_env) [root@sht-sgmhadoopcm-01 software]# pip list|grep jinja2|wc -l
0
测试2：在虚拟环境中安装第三方库，系统环境没有影响
[root@sht-sgmhadoopcm-01 software]# source test1_env/bin/activate
(test1_env) [root@sht-sgmhadoopcm-01 software]# pip install futures
(test1_env) [root@sht-sgmhadoopcm-01 software]# pip list|grep futures
futures 3.2.0
[root@sht-sgmhadoopcm-01 software]# pip list |grep futures|wc -l
0
2.virtualenvwrapper
virtualenvwrapper作用：集中管理虚拟环境
安装virtualenvwrapper
[root@sht-sgmhadoopcm-01 software]# pip install virtualenvwrapper
[root@sht-sgmhadoopcm-01 ~]# vim ~/.bash_profile
export WORKON_HOME=$HOME/.virtualenvs
export PROJECT_HOME=$HOME/workspace
source /bin/virtualenvwrapper.sh
[root@sht-sgmhadoopcm-01 ~]# source ~/.bash_profile
新建虚拟环境：mkvirtualenv [虚拟环境名称]
[root@sht-sgmhadoopcm-01 software]# mkvirtualenv test3_env
New python executable in /root/.virtualenvs/test3_env/bin/python
Installing setuptools, pip, wheel...
done.
virtualenvwrapper.user_scripts creating /root/.virtualenvs/test3_env/bin/predeactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/test3_env/bin/postdeactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/test3_env/bin/preactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/test3_env/bin/postactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/test3_env/bin/get_env_details
[root@sht-sgmhadoopcm-01 software]# mkvirtualenv test4_env
列出虚拟环境列表：workon或者lsvirtualenv
[root@sht-sgmhadoopcm-01 .virtualenvs]# workon
test3_env
test4_env
启动/切换虚拟环境：workon [虚拟环境名称]
[root@sht-sgmhadoopcm-01 .virtualenvs]# workon test3_env
(test3_env) [root@sht-sgmhadoopcm-01 .virtualenvs]# workon test4_env
删除虚拟环境：rmvirtualenv [虚拟环境名称]
(test4_env) [root@sht-sgmhadoopcm-01 .virtualenvs]# rmvirtualenv test3_env
