Django Country Context

This module solves a small problem that can be found in many sites, where the website has to support multiple countries, e.g. e-commerce website with different stores for different countries, this module allows the developer to define a context per thread, this context holds all the information about the currently available country, and allows the developer to rely on the context always to get the current country instead of passing it through the different levels of code. This module is thread-safe, it defines a different context for each thread.

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How to make django management commands send errors email to admins

I usually use django’s custom management commands to do different tasks on the web application, most of the times with a cron job running those commands. The problem is that when you’re using a cron job, you won’t get the beautiful django error email when something goes wrong. Continue reading “How to make django management commands send errors email to admins”

Python Celery Asynchronous Task Decorator

A while ago I was working on a project in Django that had many tasks that needed to be executed asynchronously such as sending emails, generating reports, and checking some database related issues.

Executing asynchronous tasks in Python can be made in multiple ways, one of them is using celery, a distributed task queue written in Python which has proved itself to be a great solid task queue system.

And if you’re using Django then there is a Django app to make your life easier, django-celery.

Now as always I like to make my own life easier also by implementing generic solutions for my needs, so I have written this simple piece of code to create a function decorator that declares the function as an asynchronous task, which means that by just adding this decorator to the function it becomes asynchronous.

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Get Online Users in Django

I was upgrading my Django Bookmarks site, and I wanted to list the online users. I searched the internet and I found a simple method, but it doesn’t work properly. So I developed my own method.

Why the simple method didn’t work?

The problem with it is that it depends on the last login date in the user model. This field is updated on every login for the user.

Imagine the following scenario:
* The user X logs in @ 1:00 pm.
* The user X posts a new post @ 1:30 pm.
* The user X comments on a previous post @ 1:35 pm.
* The user X leaves the website @ 1:40 pm.
* The user X comes back to the website @ 3:00 pm.
* The user X is logged in since the session cookie has not expired yet.
* The user X posts a new post @ 3:15 pm.
* A guest enters the website, and looks at the online users corner.

The guest won’t see X’s name in the list of online users, simply because X’s last login date is @ 1 pm, even though user X is now online and he has just posted a new post.

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