Why bother about Python versions?
I recently started a new project creating a web application. As I have a lot of Python programming experience I chose Python with Django over Ruby on Rails. At the beginning of a new project I prefer using the latest versions of the frameworks the application will depend on. Starting now with Python 2.7 would mean that sooner or later there would be additional work porting the codebase to Python 3. Yesterday, Python 3.4 was released. One of the biggest improvements is that it has pip already included which makes handling virtual environments and installing the latest release of Django really easy.
Building Python from source
The downside is, that Linux distributions do not include the latest Python release yet. Most of them still ship with Python 2.7 as default version. The next Fedora and Ubuntu releases might change that, but for now you need to compile it from source. Luckily that is not a hard task. Go to the download page and grab the latest Python release (recommended if you read the post later and a newer version was released) or past the following command into a terminal.
First make sure you have everything installed to compile Python from source.
sudo apt-get install build-essential
Before downloading create a temporary directory to make the cleanup easier. At the end you can just delete “tmpPython”.
mkdir tmpPython
cd tmpPython
wget --no-check-certificate https://www.python.org/ftp/python/3.4.0/Python-3.4.0.tgz
tar xvf Python-3.4.0.tgz
After the archive is extracted, cd into the source directory. Create a directory to install to, then run configure, build and install.
cd Python-3.4.0
sudo mkdir /opt/Python34
./configure --prefix=/opt/Python34 && make -j4
sudo make install
Now you have Python 3.4 installed on your system.
Add the the path containing the executable to your environment.
export PATH=/opt/Python34/bin:$PATH
Also make sure to add this line to your .bashrc file (or .zshrc if you’re using zsh).
echo "export PATH=/opt/Python3.4/bin:$PATH" >> $HOME/.bashrc
Creating a virtual environment
Go to the directory where you want to create the virtual environment. I recommend /opt if you collaborate with others within the environment (you have to create everything with sudo) or your home directory if you work alone. Then run pyvenv to create it.
pyvenv-3.4 djangoEnv
source djangoEnv/bin/activate
The bash prompt changes to
(djangoEnv) mpei@earth /opt
and that means that you are now within this virtual environment.
This command shows you what you have installed:
pip freeze
Installing Django
Just use pip to install the latest version of Django and its extension:
sudo pip install django django-extensions
And you’re done! You can check the installed versions by running “pip freeze” again. Maybe another blog post on Django and databases? Or the first steps in Django? We’ll see… bye bye!
