I've recently finished working in a couple of small projects and I'm about to complete another bigger one so I expect to have some hours available for new projects quite soon. If you're interested in hiring me for your next project please take a look at the services I can offer you and contact me to discuss details.

Manolo Guerrero, that funny talking Mexican dude who happens to be a jQuery god and excellent friend of mine, introduced me to Andreas Krohn, a great pal from Sweden, evil mind behind WebHostNinja, with whom I've developed a nice Google App Engine and Django based Facebook application that will go live soon and I'll discuss later.

Andreas is a highly energetic online entrepreneur and developer who's considering Django for his next project and asked me a few questions about it. These were very good questions that many may have asked before and I thought my answers could help others getting used to the Django way of thinking.

And just when I thought that setting up Apache, mod_python and Lighty with Django was cool, and I haven't even started playing with mod_wsgi or nginx (the powerful Russian HTTP server, pronounced engine X) came the requirement to move the Django application I'm developing for Facebook to Google App Engine, the latest, and it seems the coolest, player in the cloud computing arena.

While my code was running on a pure Django environment I setup the callback url in Facebook's developer application to point to my local server, some simple port forwarding in my router did the trick. Now I wanted to do the same using Google App Engine's development server.

Understanding and using the power of regular expressions, or simply regex, is a must for every smart programmer. Django uses them quite often on its elegant URLConf system.

I've been using regular expressions for a very long time and have read many books about them but if I have to recommend just one I'll go for the classic Mastering Regular Expressions by Jeffrey Friedl.

And nothing better to test you're on the right track while writing your own regular expressions than Kodos, a simple but nice Python based tool, easy to install from any Debian based distro with a quick sudo apt-get install kodos.

I recently commented about using the right quotes with Python and simplejson and today I found a similar issue with Django.

It happens when using the {% url %} tag on the template system in Django 1.0. {% url %} helps you to avoid hardcoding links and relies on naming your url patterns.

Let's suppose we have a url like this in our URLConf:

url(r'^add/chatroom/(?P\w+)$', 'myapp_chatroom_add', name='myapp_chatroom_add'),

Now you could insert {% url %} in your template to get the url for a link:

{% url myapp_chatroom_add chatroom_data="abc" %}

Notice I'm passing the string "abc" using double quotes as the chatroom_data parameter.

And here's the important part, these two won't work:

{% url myapp_chatroom_add chatroom_data=abc %}

which does not use quotes at all, or this one:

{% url myapp_chatroom_add chatroom_data='abc' %}

which uses single quotes.

The errors may vary depending on how your code works but the fact is to remember that when passing string based parameters to {% url %} you need to always use double quotes.

If you're using numbers you could use either no quotes or double quotes. Single quotes will never work.

It's Saturday morning and I started the day reading another chapter of Introduction to Algorithms (Cormen, Leiserson, Rivest y Stein), a must read for every programmer no matter which your favorite language is.

And while I tested some Python code I tried to remember when I started to program and in which language. It was 24 years ago, in 1984, I was twelve and my first computer, a PC XT (Intel 8088, 4.77 MHz) had less than six months at home.

The language was Basic, first as BASICA and later as GW-Basic running on DOS 3.2.

And you? When did you learn to program and in which language?

It's October 2008 and there's no doubt now that serious web development requires working with frameworks, software that allows us, lazy coders, to forget about repetitive tasks and focus on the specifics of each project, the stuff that makes them truly unique.

It's pretty obvious too that Django, the Python based web framework, is attracting more developers and companies lately. Guido is a googler since 2005 and the recently launched Google App Engine uses Python and Django. Seriously, there's not a better time to jump into the Django train (no pun intended RoR guys).

Experienced programmers can start writing Django applications quickly thanks to the excellent documentation and the free Django book. I've also read and can recommend Practical Django Projects, by James Bennett, part of the Django team, and Learning Website Development with Django, by Ayman Hourieh, a very smart and young Google engineer.

Django is really a web framework for perfectionists with deadlines. I'm very near to one and have almost finished coding what will be my first Django based application for Facebook. Yes, I've got a few articles about that coming soon as well.

So, everything looks great under the Sun on Djangoland? Well, there's something that bothered me since I started a few months ago: deployment on a production environment. The documentation and most books get us up and running quickly with the included development server and then just refer us to the recommended Apache and mod_python settings for more.

Unfortunately, specially if you're used to the common Linux, Apache, MySQL and PHP setup, like I was, you may be need more detailed instructions and that's why I decided to write this tutorial on how to setup Apache, mod_python and a reverse proxy to Lighttpd for Django.

My little Django and Facebook project needed to do some JSON processing, time for using simplejson then.

My application will receive a string of JSON and transform it to a dictionary, pretty simple. Let's run a test first, starting with the Python shell, or better yet, iPython, and importing the module:

import simplejson

Now let's define a string using JSON notation and pass it to simplejson:

band = "{'name': 'Mando Diao', 'genre': 'rock and roll', 'bid': 19383}"
json = simplejson.loads(band)

And we get a ValueError exception. Let's try using simple quotes for enclosing the whole string and double quotes for the JSON keys and values:

band = '{"name": "Mando Diao", "genre": "rock and roll", "bid": 19383}'
json = simplejson.loads(band)

And there you go, no error now:

print json
{u'genre': u'rock and roll', u'bid': 19383, u'name': u'Mando Diao'}

I find a little strange that this problem happens as I've been using either type of quotes for most of my Python coding. Had you noticed this problem? I've checked simplejson's documentation and could not find anything related to this.

One last word, the new Python 2.6 includes a json module, which is a refactored simplejson. Neat.

I recently installed the new Flock 2. I've always liked Flock and the way it integrates the browser with so many social web services. And it's now based on Firefox 3 code so it seems to run faster and more stable than before.

But right after installing and browsing a bit, I'm on Ubuntu Hardy 64 bits, I noticed my Internet connection was gone. It wasn't really gone but Flock couldn't connect to any site external to my computer.

I tried googling around and found the fix. The funny thing is that what my search returned was an article I had written with the solution some time ago. Here's the solution to the Internet connection lost in Flock in Spanish.

And here's the English version.

How to fix the connection lost problem with Flock

Open Flock and follow these steps:

• Write about:config on Flock's address bar.
• Write ipv6 to filter the parameters list.
• We're looking for network.dns.disableIPv6. Right click on it and choose Toggle to change the value to true.
• Presto! Flock now can get online without problems in Ubuntu Hardy.

The latest Facebook changes have introduced many nice touches for both users and developers but something that's causing lots of troubles is the bookmarks feature for applications.

Before the changes every Facebook user had a sidebar on the profile with the applications he or she had installed, now the applications are on the bottom part of the page inside an expandable menu but the only applications listed there are the ones a user has bookmarked.

The problem is that the bookmarking process is a mess. There's a long thread on the Facebook developer's forums that starts with a post listing all the clicks and guesses needed to get bookmarks working, and that's in the case of a smart user. Regular users may never find out how bookmarks work and lots of nice applications, including the ones a user accepted to add, will be lost.

That's not good for users and it's super bad for Facebook applications developers. By the way, if you're not coding a Facebook application yet you may will be doing it soon, trust me.

What most people are asking for is that Facebook forgets about its bookmarks concept and simply provide a menu listing the applications a user has recently added and/or used. If you want to have your say on this matter I suggest you post on the original discussion at Facebook.

Of course, a clearly written and visible FAQ for users would be great too.