Book Image

Django 1.1 Testing and Debugging

Book Image

Django 1.1 Testing and Debugging

Overview of this book

Bugs are a time consuming burden during software development. Django's built-in test framework and debugging support help lessen this burden. This book will teach you quick and efficient techniques for using Django and Python tools to eradicate bugs and ensure your Django application works correctly. This book will walk you step by step through development of a complete sample Django application. You will learn how best to test and debug models, views, URL configuration, templates, and template tags. This book will help you integrate with and make use of the rich external environment of test and debugging tools for Python and Django applications. The book starts with a basic overview of testing. It will highlight areas to look out for while testing. You will learn about different kinds of tests available, and the pros and cons of each, and also details of test extensions provided by Django that simplify the task of testing Django applications. You will see an illustration of how external tools that provide even more sophisticated testing features can be integrated into Django's framework. On the debugging front, the book illustrates how to interpret the extensive debugging information provided by Django's debug error pages, and how to utilize logging and other external tools to learn what code is doing.
Table of Contents (17 chapters)
Django 1.1 Testing and Debugging
Credits
About the Author
About the Reviewer
Preface
Index

Testing multithreaded behavior


In the previous section, we encountered a few environmental differences between running under the development server and running under Apache. Some of these (for example, file permissions and Python path differences) caused problems that had to be overcome before we could get the project functioning properly under Apache. One difference we observed, but have not yet encountered a problem with, is multithreading.

When we checked the error log in the previous section we could see that mod_wsgi had started one process with 15 threads, each ready to handle an incoming request. Multiple requests that arrive at the server nearly simultaneously, then, will be dispatched to different threads for handling, and the steps of their execution may be arbitrarily interleaved in real time. This can never happen with the development server, which is strictly single threaded, ensuring each request is fully processed before processing of the next one is started. It also never...