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Practical Django Projects
Chromodromic writes "Apress's newest Django offering, Practical Django Projects by James Bennett, weighs in lightly at 224 pages of actual tutorial content, but trust me, they're dense pages. Filled with pragmatic examples which directly address the kinds of development issues you will encounter when first starting out with Django, this book makes an important addition to the aspiring Django developer's reference shelf. In particular, the book's emphasis on demonstrating best practices while building complete projects does an excellent job of accelerating an understanding of Django's most powerful features — in a realistic, pragmatic setting — and which a developer will be able to leverage in very short order." Read below for the rest of Greg's review.
Practical Django Projects
author
James Bennett
pages
256
publisher
Apress
rating
8/10
reviewer
Greg McClure
ISBN
1-59059-996-9
summary
A practical introduction to the Pythonic Django web framework.
This book serves an important function by providing progressive, useful examples of Django's role in the development of realistic projects. During the course of the tutorial you build three basic apps: A simple brochureware-oriented CMS, a complete blogging system (with Akismet spam protection and RSS feeds, among other features), and a social code-sharing site similar to that found at djangosnippets.org (with account signups, syntax highlighting via pygments, and bookmarking features — the whole enchilada). You may or may not find these projects
immediately relevant to your work or goals, but the projects themselves are really just platforms for delving into Django's nooks and general philosophy. It's an important point to make about the book especially, because though Django itself provides potent facilities for creating reusable code while preserving a high degree of flexibility, "magic" is kept to a minimum compared to some other popular frameworks. It follows that maximizing your knowledge of Django's inner workings through familiar paradigms is critical to making the framework perform to your best advantage. The book excels at accomplishing this goal.
Along these lines, a lot of territory is covered in a short span. You're introduced to a couple of Django's contrib apps — code which comes with a normal Django installation and which cleanly plugs into your own application while remaining extremely customizable. After being ushered through a straightforward installation and database configuration, your first exposure to development is through the contrib app most frequently lauded in the Djangoverse, Django's deservedly well known admin system. But immediately, emphasis is shifted from the basic features of the system to the ways it can be customized. This approach of introducing a feature and then modifying or extending it is repeated immediately with Django's Flatpages contrib app, a very basic CMS which, again, comes with Django and installs with a single line of code and one command.
By the time you've finished the third chapter, you've built the foundation of a typical brochureware site, complete with a working search system and a completely functional customized admin with which you may modify your content using a javascript-based HTML editor (TinyMCE). Pretty impressive for 41 fast-moving pages.
The strongest feature of the book, though, is not the speed or facility with which features are presented, but rather the way these features are always demonstrated with a mind to Django's strongest argument: how easy it is to create reusable code, once you understand the framework's approach. As you move through the next four chapters of building the blogging system, the establish-modify-extend technique of presentation does a good job of working you through various standard Django features — generic views (a very important concept which is illuminated nicely), code organization, ORM techniques, template inheritance, and so forth — and you're smoothly shown the ways by which you will be able to incorporate much of the code you write into your future work. As you begin your last project, the code-sharing app, you've gotten an overview of both coding and workflow techniques which work best with Django. The final chapters reinforce everything you've learned while still introducing new material on library integration, form handling and the newforms library, and code distribution.
The overall approach is very effective, though I found I had to trust the tutorial a little at first in order to get the most out of it. The projects initially seemed somewhat vanilla, so it wasn't until I really focused on the organization of the material that I discovered the book's strengths. Now I wish I'd had this book years ago.
Issues? I had only one, really. The material presents itself as a tutorial suitable for those who are just starting out with Python. For example, near the beginning of the material the def keywork is pointed out as the way Python functions are declared, and similar kinds of notes and comments pepper the tutorial, somewhat unevenly, as well. While I appreciate the impulse to make the material as accessible as possible, I'm skeptical of the book's role as truly introductory at that level, although I could see some experienced developers, especially those coming from other languages, benefiting from these quick notes. But my feeling in general would be that if you're so new to Python that the def keyword is a revelation, you might be better off starting elsewhere before you dive into Django.
This is a minor point, though, and if you're willing to give the material the time, you'll appreciate what Django has to offer more and more with every page. The book maintains a brisk pace which I truly appreciated. And if you've struggled with Django in the past, or you've wanted to learn more about what to do beyond getting the admin running, "Practical Django Projects" is an excellent foundation for your Django education. I absolutely recommend this as the Django book I've found to be, by far, the most useful.
You can purchase Practical Django Projects from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Along these lines, a lot of territory is covered in a short span. You're introduced to a couple of Django's contrib apps — code which comes with a normal Django installation and which cleanly plugs into your own application while remaining extremely customizable. After being ushered through a straightforward installation and database configuration, your first exposure to development is through the contrib app most frequently lauded in the Djangoverse, Django's deservedly well known admin system. But immediately, emphasis is shifted from the basic features of the system to the ways it can be customized. This approach of introducing a feature and then modifying or extending it is repeated immediately with Django's Flatpages contrib app, a very basic CMS which, again, comes with Django and installs with a single line of code and one command.
By the time you've finished the third chapter, you've built the foundation of a typical brochureware site, complete with a working search system and a completely functional customized admin with which you may modify your content using a javascript-based HTML editor (TinyMCE). Pretty impressive for 41 fast-moving pages.
The strongest feature of the book, though, is not the speed or facility with which features are presented, but rather the way these features are always demonstrated with a mind to Django's strongest argument: how easy it is to create reusable code, once you understand the framework's approach. As you move through the next four chapters of building the blogging system, the establish-modify-extend technique of presentation does a good job of working you through various standard Django features — generic views (a very important concept which is illuminated nicely), code organization, ORM techniques, template inheritance, and so forth — and you're smoothly shown the ways by which you will be able to incorporate much of the code you write into your future work. As you begin your last project, the code-sharing app, you've gotten an overview of both coding and workflow techniques which work best with Django. The final chapters reinforce everything you've learned while still introducing new material on library integration, form handling and the newforms library, and code distribution.
The overall approach is very effective, though I found I had to trust the tutorial a little at first in order to get the most out of it. The projects initially seemed somewhat vanilla, so it wasn't until I really focused on the organization of the material that I discovered the book's strengths. Now I wish I'd had this book years ago.
Issues? I had only one, really. The material presents itself as a tutorial suitable for those who are just starting out with Python. For example, near the beginning of the material the def keywork is pointed out as the way Python functions are declared, and similar kinds of notes and comments pepper the tutorial, somewhat unevenly, as well. While I appreciate the impulse to make the material as accessible as possible, I'm skeptical of the book's role as truly introductory at that level, although I could see some experienced developers, especially those coming from other languages, benefiting from these quick notes. But my feeling in general would be that if you're so new to Python that the def keyword is a revelation, you might be better off starting elsewhere before you dive into Django.
This is a minor point, though, and if you're willing to give the material the time, you'll appreciate what Django has to offer more and more with every page. The book maintains a brisk pace which I truly appreciated. And if you've struggled with Django in the past, or you've wanted to learn more about what to do beyond getting the admin running, "Practical Django Projects" is an excellent foundation for your Django education. I absolutely recommend this as the Django book I've found to be, by far, the most useful.
You can purchase Practical Django Projects from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Boba Fett's dad.
If you can read this, I forgot to post anonymously.
Oh, yeah. And building Django apps is FAST.
My blog
Hi, I'm James and I wrote Practical Django Projects, and I have a confession to make: I cheated while writing the book. You see, I'm also Django's release manager, which meant I had a good idea of what would land in trunk and what would change by the time we went to press. Except for activating/hacking on the admin interface (the admin refactor just landed over the weekend), everything in the book should be up-to-date and usable on the Django 1.0 alpha we released Monday.
whats rails?
I have some experience using mod_perl & Django in mod_python. Django provides much that perl does not, and I love writing perl for backend utilities and CGI.
Django templates do not allow the scriptlet mentality of others like JSP & mod_perl. They have a short list of commands, a loop, an IF-statement, and some text filters. This forces users to separate computation (in perl/python code) from display (in the template). The template takes a dictionary of named (keyed ) objects and prints the fields.
Django has an Object-Relational Model built-in to the system. Programmers write a models.py module full of ORM classes. Then, the Django utilities build SQL database tables to match the models. The Django Object-Relational Model has no equal so far as I've seen.
Django enforces the MVC web application. Most other web frameworks let the bad habits creep in.
Devoid of context, yes, I can see that.
In context, however, not so much. Consider Django's built-in template system (which you don't have to use, btw; most people do because it leads to easier interoperability with arbitrary applications, but you're free to drop in whatever you like -- it's just Python code on the backend); most people instinctively get upset when they find out that it isn't just the host programming language embedded into HTML (a la PHP, ERB, "classic" ASP, etc.). But I've found that it's extremely rare for me to have a need for such a thing, and when I do the template system is extensible from the Python side, so I can implement what I need and get on with life. A good example I ran into the other night while helping someone debug: he was doing a product-review site where each product had a government-issued safety rating, from one to five stars. What he wanted was basically a way to say something like:
{% if product.safety_rating > 3 %}This product has a high safety rating.{% endif %}
(the curly-brace constructs are how Django's template language delimits certain constructs, such as conditionals, loop expressions, etc.)
Now, you can't actually do this: arbitrary Python expressions like product.safety_rating > 3 aren't supported by the language. What he ended up doing was moving this logic into a method on the object representing products, so it became if product.has_high_safety_rating instead. For most cases in most applications, this is a better option (it's more reusable, and leads to easier maintenance since you don't have magic numbers hard-coded everywhere). And for times when you need it, you can dip down to the Python level and extend whatever syntax you need into the template system (one night I sat down and implemented a bunch of comparison expressions; it took about five minutes).
The parent comment you're responding to is also slightly incorrect on a few points; for example, Django doesn't "enforce" MVC in any particular way and actually deviates from it in some ways that made sense for the Web (e.g., the concept of the controller really has no place in most web applications, since there's only a single channel for interaction with the app: HTTP). All Django cares about is that for each URL you want to handle, you provide a callable object which accepts an HTTP request as its first argument and returns an HTTP response. Beyond that, the sky's the limit. Django also doesn't force you to use its ORM; several of the bundled applications in django.contrib make use of it (since, if you've got Django installed, they can rely on the ORM being available), but nobody says you have to use it in your apps.