DjangoTricks: July 2008

2008-07-16

EuroPython 2008

I started writing this post at the airport just before flying back from Vilnius to Berlin. EuroPython 2008 - the three-days conference and sprints afterwards - gave me loads of information, new relations, and better understanding of the big image of Python developers' community.

Some highlights from the conference follow.

During video conference the author of Python programming language Guido van Rossum encouraged using Python 2.6 just after the release, but said that Python 3.0 still shouldn't be used for production. The good future-proof practices are inheriting from object for classes, using xrange(), sorted(), and zip() functions, "//" for floor divisions, and dict.iterkeys(). The full porting to 3.0 guide will be probably written and published in the python.org site.

Clone Digger is a project from Google Summer of Code 2008 for finding similar pieces of code which could be optimized by moving that to parameterized functions.

Restrictive Python is a project which blocks the user from executing dangerous functions or methods or accessing files which might harm the system. You can try Restrictive Python out in the simulated terminal.

Python is an interpreted language and if you want to deploy a project writen in Python, you have to be sure that the end user will have Python interpreter installed there. O you can create an executable file from Python project using one of the following tools: Py2exe, PyInstaller, or BBFreeze.

There is a combined installer of Python, SQLite, and Django for Windows and it is called Instant Django.

Django DB External Scheme Evolution Branch is a separate application for doing DB scheme changes easily without manual DB field editing.

Honza Král showed the essentials of the new-forms admin to which I am going to port our Django projects the next days. Directly from him I learned that new forms will still have validators which will work only to check the value of that one specific field (not related to other fields). If some multiple field validation is necessary, the clean method for the form should be overwritten. All the global field-unrelated form errors will be passed to {{ form.non_field_errors }} variable.

Christian Scholtz presented PYOGP which is Python-based environment for testing the Open Grid Protocol used for exchanging avatars and other objects among virtual realms like different regions of Second Life.

Ricardo Quesada and Lucio Torre told us about cocos2d - a framework made in Python for presentations and sprite-based 2D games.

If you ever need to export some data from a database to Excel Sheet or import from Excel, you can do that not only in CSV (Comma Separated Values) format. You can also use the original XLS format with one of the following libraries: xlrd, xlwt, or pyExcelerator. I successfully used the latter one last week.

CVS and SVN are not the only version control management systems in the world :D. The others like Mercurial, Git and Bazaar are also worthy checking. These are all distributed systems which mean that they don't have one centralized source. Bazaar is written in Python and has API for manipulating information about revisions, committers, and other version-control-related stuff.