virtualenv技巧

看了你就懂了
https://segmentfault.com/a/1190000004079979

你在一个机器上 开发不通的项目，需要不通版本的python怎么办

1.首先安装python3
http://www.th7.cn/Program/Python/201512/743392.shtml

 cd /usr/local/
curl -O https://www.python.org/ftp/python/3.5.0/Python-3.5.0.tgz
tar -zxf Python-3.5.0.tgz
cd Python-3.5.0/
./configure
make
make install

第三方的东西，最好下载到这个目录下

[root@hk45-node02-47 Python-3.5.0]# cd /usr/local
[root@hk45-node02-47 local]# ls
aegis  bin  etc  games  include  lib  lib64  libexec  nginx  nom  Python-3.5.0  Python-3.5.0.tgz  sbin  share  src

老的：

[root@hk45-node02-47 local]# /usr/bin/python -V
Python 2.7.5

[root@hk45-node02-47 local]# /usr/bin/pip -V
pip 8.1.2 from /usr/lib/python2.7/site-packages (python 2.7)

新的：

[root@hk45-node02-47 local]# /usr/local/bin/python3 -V
Python 3.5.0

[root@hk45-node02-47 local]# /usr/local/bin/pip3 -V
pip 7.1.2 from /usr/local/lib/python3.5/site-packages (python 3.5)

install python3.5 but you did not install pip3.5 , I suggest you to install python3.4 and pip3.4

el7 install python3.4 and pip3

[root@us44-47 local]# yum install epel-release -y
[root@us44-47 local]# yum install python34 -y
[root@us44-47 local]# curl https://bootstrap.pypa.io/get-pip.py | python3.4

[root@singapore-47 local]# which python3
/usr/local/bin/python3
[root@singapore-47 local]# which python3.4
/usr/bin/python3.4
[root@singapore-47 local]# which python3.5
/usr/local/bin/python3.5

[root@singapore-47 local]# ll /usr/local/bin/python3
lrwxrwxrwx 1 root root 9 6月  20 13:36 /usr/local/bin/python3 -> python3.5
[root@singapore-47 local]# ln -sf /usr/bin/python3.4 /usr/local/bin/python3
[root@singapore-47 local]# python3 -V
Python 3.4.3

2.安装virtualenv，virtualenvwrapper

[root@hk45-node02-47 local]# pip3 install virtualenv
[root@hk45-node02-47 local]# pip3 install virtualenvwrapper

自己心里要知道自己安装的virtualenvwrapper.sh在哪里
[root@hk45-node02-47 local]# which virtualenvwrapper.sh
/usr/local/bin/virtualenvwrapper.sh

[root@hk45-node02-47 local]# vim ~/.bashrc
添加：
export WORKON_HOME='~/.virtualenvs'
source /usr/bin/virtualenvwrapper.sh

以后，你就可以使用workon了

3.现在你的机器上有了python2.7 和python3，你需要用virtualenv 搞一个 python3的环境

方式1:不能用workon，每次都要source一下

[root@hk45-node02-47 ahao.mah]# virtualenv -p /usr/local/bin/python3 csvt15
Running virtualenv with interpreter /usr/local/bin/python3
Using base prefix '/usr/local'
New python executable in /home/ahao.mah/csvt15/bin/python3
Also creating executable in /home/ahao.mah/csvt15/bin/python
Installing setuptools, pip, wheel...done.
[root@hk45-node02-47 ahao.mah]# ll csvt15
总用量 16
drwxr-xr-x 2 root root 4096 6月  17 22:58 bin
drwxr-xr-x 2 root root 4096 6月  17 22:58 include
drwxr-xr-x 3 root root 4096 6月  17 22:58 lib
-rw-r--r-- 1 root root   60 6月  17 22:58 pip-selfcheck.json

方式2：可以用workon，简单方便，环境存储在$WORKON_HOME 下

[root@hk45-node02-47 ahao.mah]# mkvirtualenv -p /usr/local/bin/python3 csvt16
Running virtualenv with interpreter /usr/local/bin/python3
Using base prefix '/usr/local'
New python executable in /root/.virtualenvs/csvt16/bin/python3
Also creating executable in /root/.virtualenvs/csvt16/bin/python
Installing setuptools, pip, wheel...done.
virtualenvwrapper.user_scripts creating /root/.virtualenvs/csvt16/bin/predeactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/csvt16/bin/postdeactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/csvt16/bin/preactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/csvt16/bin/postactivate
virtualenvwrapper.user_scripts creating /root/.virtualenvs/csvt16/bin/get_env_details
(csvt16) [root@hk45-node02-47 ahao.mah]# python -V
Python 3.5.0