Python Virtual Environments (virtualenv)
- Testing different versions of libraries (one API might require python-requests v3 another might need v2)
Using your first virtualenv
To create your first virtualenv, run:
This will create a virtual environment without any of the packages installed on your Raspberry Pi. If you want to keep the packages already installed, add the "--system-site-packages" option to the virtualenv command.
To begin using the virtualenv, change into the new directory and run:
Notice that the command prompt changes, once you enter the venv so you know where you are. The (flaskenv) will disappear once you exit the virtualenv later.
At this point, any python libraries you install will only be installed in that virtual environment and will not affect the rest of the system. To see what packages you have installed, run:
On my system, there are only 5 packages present in flaskenv, while in a virtualenv created with --system-site-packages there are a bit over 10. Remember that installing yolk only affects the current virtualenv, so to run it again on your base system, you will need to do easy_install again.
To use the virtualenv in a python script, change the #!/usr/bin/python at the top of the file to #!
To get out of the virtualenv, run "deactivate" at the bash prompt.