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

Elements of the debug page


Now let's turn our attention to the debug page we've encountered. There is quite a lot of information on it, split into four parts (only the first and beginning of the second are visible in the screenshot). In this section, we focus on what information, in general, is included in each part of the debug page, noting the values we see on this page simply as examples. Later in the chapter, we will see how the specific information presented on this debug page can be used to fix the error we have made.

Basic error information

The very top part of the debug page contains basic error information. Both the page title and the first line of the page body state the type of exception encountered, and the URL path contained in the request that triggered the exception. In our case, the type of exception is a TypeError, and the URL path is /. So, we see TypeError at / as the first line on the page.

The second line contains the exception value. This is usually a specific description...