Sunday, July 06, 2008

Converting a Django Site to newforms-admin

Right after I learned about Django at OSCON 2006, I created a prototype to replace an existing PHP site. Due to various distractions, I haven't done much with that Django site since then and it never went live, but I've come back to it recently.

My first order of business was to upgrade from 0.95 to something modern. The first stop was to upgrade to trunk. Following the instructions on the Django site, I got it running on trunk and only had to change maxlength to max_length in my models.

Since, newforms-admin will be merging with trunk soon, porting to newforms-admin was my next step. I pointed my django install at my newforms admin svn tree and let it rip - i.e., I didn't bother reading any documentation or anything.
It blew up with a nasty-looking traceback that ended with this:

func(self, *args, **kwargs)
TypeError: __init__() got an unexpected keyword argument 'prepopulate_from'

A quick Google search turned up this thread on the Django Users mailing list. Five minutes of reading the newforms-admin wiki page and refactoring my code, and I was up and running. So, despite the ugly-looking traceback, it just wan't that bad.

Granted, my project is pretty small because I never had much time to work on it. However, all in all, the conversion process from 0.95 to the bleeding edge of newforms-admin was pretty painless.

Another happy Django user,

Book: Effective Java

Effective Java, 2nd Edition by Joshua Bloch. ISBN 0321356683

This is the best book that I've read that I didn't know I needed to read. If you are a pretty good Java programmer, and you want to be better, this is a book you should definitely read.

Back in the day (BITD), we had Scott Meyer's book Effective C++, and we needed it. Even without templates and all the "new" things in C++, C++ was a large and complex language. I loved Effective C++ not only because it had lots of tips to keep you out of trouble when coding C++, but also because the organization was brilliant: each tip was about the right length to be read while sitting on the can.

I ignored the first edition of Effective Java book when it came out because I smugly assumed that Java was so superior to C++ (Java is C++ with the pointy bits filed down) that it wasn't really necessary. And that may or may not have been true in the 1.0 or 1.1 days of Java, but with the release of Java 5, the language has certainly grown and is now sufficiently complex that a book like this is a necessity, especially if you've recently moved up to Java 5 or Java 6. Lucky for me, this book landed on my desk against my will.

The book uses that same sitting-on-the-can format from Effective C++; the information is broken down into nice, small bits of information that you can read one or two at a time. These are grouped into 10 sections. There are specific sections for Java 5 features like Generics and Enumerations, which is great for people like me who were stuck on 1.4 for far too long.

What is really amazing about this book is that I learned a lot about topics that I thought I already knew about. For example, I've used serialization in a number of formats (built-in and do-it-yourself) for years, but I realized there's a lot more that I had no idea about. I will certainly think twice before doing any serialization in the future.

Unless you're the sort that knows the Java Language Specification by heart, you need to read this book.