Alchin Marty - Pro Python

Pro Python

Copyright 2010 by Marty Alchin

All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher.

ISBN-13 (pbk): 978-1-4302-2757-1

ISBN-13 (electronic): 978-1-4302-2758-8

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President and Publisher: Paul Manning

Lead Editor: Duncan Parkes, Tom Welsh

Technical Reviewers: George Vilches

Editorial Board: Clay Andres, Steve Anglin, Mark Beckner, Ewan Buckingham, Gary Cornell, Jonathan Gennick, Jonathan Hassell, Michelle Lowman, Matthew Moodie, Duncan Parkes, Jeffrey Pepper, Frank Pohlmann, Douglas Pundick, Ben Renow-Clarke, Dominic Shakeshaft, Matt Wade, Tom Welsh

Coordinating Editor: Mary Tobin

Copy Editors: Nancy Sixsmith, Angel Alchin

Compositor: Bytheway Compositors

Indexer: John Collin

Cover Designer: Anna Ishchenko

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About the Author

Marty Alchin is a professional programmer with a passion for the Web. His work with Django, the popular Web framework, led him to write several articles about Python, to speak at PyCon and even to write his first book, Pro Django , which was published by Apress in December of 2008.

In addition to writing for print, Marty keeps a blog at http://martyalchin.com/, where he writes about Python, Django and anything else that strikes his fancy.

About the Technical Reviewer

George's personal time is split between tinkering with open source projects and enjoying the company of his wife Kate, their corgi and their two cats (all of whom would prefer he stop tinkering and attend to them more).

Acknowledgments

I wouldn't have even started this project if not for the endless encouragement from my lovely wife, Angel. She's been my sounding board, my task manager, my copy editor and my own personal cheerleader. There's no way I could do anything like this without her help and support.

I'd also like to thank my technical reviewer, George, for everything he's done to help me out. He's gone above and beyond the limits of his role, helping with everything from code to grammar and even a good bit of style. After enjoying his help on Pro Django , I wouldn't have even signed on for another book without him by my side.

Lastly, I never would've considered a book like this if not for the wonderful community around Python. The willingness of Python programmers to open their minds and their code is, I believe, unrivaled among our peers. It's this spirit of openness that encourages me every day, leading me to discover new things and push myself beyond the limits of what I knew yesterday.

We learn by doing and by seeing what others have done. I hope that you'll take the contents of this book and do more with it than what I've done. There's no better reward for all this hard work than to see better programmers writing better code.

Introduction

When I wrote my first book, Pro Django , I didn't have much of an idea what my readers would find interesting. I had gained a lot of information I thought would be useful for others to learn, but I didn't really know what would be the most valuable thing they'd take away. As it turned out, in nearly 300 pages, the most popular chapter in the book barely mentioned Django at all. It was about Python.

The response was overwhelming. There was clearly a desire to learn more about how to go from a simple Python application to a detailed framework like Django. It's all Python code, but it can be hard to understand based on even a reasonably thorough understanding of the language. The tools and techniques involved require some extra knowledge that you might not run into in general use.

This gave me a new goal with Pro Python : to take you from proficient to professional. Being a true professional requires more experience than you can get from a book, but I want to at least give you the tools you'll need. Combined with the rich philosophy of the Python community, you'll find plenty of information to take your code to the next level.

Who This Book Is For

Because my goal is to bring intermediate programmers to a more advanced level, I wrote this book with the expectation that you'll already be familiar with Python. You should be comfortable using the interactive interpreter, writing control structures and a basic object-oriented approach.

That's not a very difficult prerequisite. If you've tried your hand at writing a Python applicationeven if you haven't released it into the wild, or even finished ityou likely have all the necessary knowledge to get started. The rest of the information you'll need is contained in these pages.

What You'll Need

This book is written with the latest versions of Python in mind, so most of the examples assume that you're already using Python 3.1, which is the latest official release as of the date of publishing. I don't take the jump to Python 3 lightly, though, so there are plenty of compatibility notes along the way, going all the way back to Python 2.5. As long as your copy of Python was released in the last few years, you'll be all set.

Nearly all the packages used in this book come from the Python Standard Library, which ships with every Python installation. Some sections will reference third-party libraries that aren't included in that bundle, but those are strictly informative; you won't lose out if you don't have them installed.

Source Code

The code for all the examples in this book is available at http://propython.com/.