Here’s a nice short function for flattening irregular lists in Python that I found on Stackoverflow a few weeks back. It returns a generator so should work fine for very big lists.

def flatten_list(object_list):
    """
    Flattens a list of objects.
    """
    for element in object_list:
        if isinstance(element, collections.Iterable) and not \
                isinstance(element, basestring):
            for sublist in flatten_list(element):
                yield sublist
        else:
            yield element

I tested it with lists like the following and it did the job: …

I must have ran this command a hundred times by now but could never remember it:

sudo openssl req -x509 -nodes -days 3650 -newkey rsa:2048 -keyout example.key -out example.crt

This will create a self-signed SSL certificate with an expiration of 10 years using a 2048-bit key. You can use this certificate with Apache2, Nginx, etc.

I decided to create a separate GitHub project for the Ansible playbook I'm currently using to fully provision a production server for my open-source app, GlucoseTracker, so it can be reused by people who are using the same stack.

You can download the playbook here: https://github.com/jcalazan/ansible-django-stack

The playbook can fully provision an Ubuntu 12.04 LTS server (will test 14.04 soon) from the base image with the following applications, which are quite popular in the …

I had to rebuild my Rackspace VPS last night where my Django app runs as I wanted to downgrade it because it was underutilized. Since I was already at the lowest tier for that category of servers, there's no option to resize it down, I would need to spin up a new server from a different server category.

Thanks to Ansible, though, provisioning a new server with all the applications and configurations I needed …

I've been working on fully automating server provisioning and deployment of my Django app, GlucoseTracker, the last couple of weeks with Ansible. Since I made this project open-source, I needed to make sure that passwords, secret keys, and other sensitive information are encrypted when I push my code to my repository.

Of course, I have the option to not commit them to the repo, but I want to be able to build …