Set virtualenv on Python projects
Sometimes we need different python packages versions in different projects. It’s like to have 3 computers, and running a different Python project on each computer, and the first project is using Django 1.8, the second project Django 1.7, and the third project Django 1.9.4.
Really I need 3 different computers to do that? Not at all.
Virtualenv is the hero, downloadable from pip, and it make our life easier. It let us to have a lot of Python projects, using their different dependence and versions, all living at the same computer but different environment. Check out the next image.
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To install virtualenv, just you need to type:
pip install virtualenv
This line will download, install and config virtualenv and their own dependence.
Now we are enabled to create a new virtual environment over any existing Python project. For this example, we already have a project called “mall4g”. We need to browse to the directory and run the command, where “mall4g” is a directory.
virtualenv mall4g
This will create extra directories: lib, bin, include, local. Probably you want to ignore that directories when you push your code to Git.
Now, to activate:
source bin/activate
Done. Now, all python packages installed by using pip, will be located automatically under our “local” directory. No stress. No more problems.