I recently decided to try and create a web app and picked Tornado as my web server, because it is also being used in IPython. I like learning new tools by reading books about them, so I got my hands on a copy of Introduction to Tornado and got started.

The book is pretty thin, which I think in this case is a good thing. Its not meant to exhaustively describe all features Tornado has to offer, but rather a gentle introduction. The book covers all of the important elements to get you started:

• Creating templates
• Extending templates with Javascript and CSS
• Interacting with databases (MongoDB in this case)
• Making your web app asynchronously
• Basic security features and authentication
• Signing in with Twitter and Facebook's OAuth

The book features several nice examples, like a shopping cart for a bookstore, asynchronously keeping tabs on how many items are remaining. A simple Twitter client displaying your latest tweets, a Facebook client showing your timeline, both dealing with authentication. Most examples worked pretty well, though I had some issues getting the Twitter client working, because of errors I made in the callback url on localhost. I didn't get the Facebook example working for the same reason, but its not a big issue.

Overall, I found it a pretty useful book. While I was already somewhat familiar with Web Apps through Udacity and Coursera courses, it was good to get a bit more formal explanation about topics like routing, handlers and templates. I also liked the way they explained what each part of the code did, instead of assuming you had already figured it out. So while its a short read, I think its a nice introduction to Tornado to get you going.