This book is nothing more than a handful of code examples that you can just as easily get from the web. There's nothing in the way of overall architecture, insightful approaches to using Twisted in an application setting, etc. Save your money and read the web pages. Worst O'Reilly book ever.

This book was disappointing to me. It does not cover Twisted fundamentals very well or comprehensively, but is rather a collection of few large code-examples and verbose commentary. For an introductory (or 'essentials' as the title state) material to Twisted, you are better off with the online manuals.

Granted, there are a few "oh - that's clever" moments in the book, but those are buried in the examples and hard to look up for future reference.

The bulk of the book shows examples for web clients and servers (simple stuff, not useful since easier-to-use and more powerful tools/libraries exist) and low-level pop, smtp, imap and nntp servers and clients (probably not very common in today's applications).

I haven't used Twisted extensively in a real project, but I have read the online docs and fiddled with small scripts - and the "new" things beyond them that I discovered reading this book can be counted on the fingers of one hand (namely Perspective Broker, authentication and SSH stuff).

I would have liked this book to be a more comprehensive overview of twisted's fundamentals and the base-protocols it provides - with more examples of custom protocols - since that's probably what most people turn to Twisted for.

Are you a developer who wants to start building applications using twisted? If you are, then this book is for you! Author Abe Fettig, has done an outstanding job of writing a book that contains lots of examples of working code, with thorough notes and explanations of how you can use Twisted to do useful things.

Fettig, begins by covering downloading and installing Twisted, and some additional libraries, on the operating system of your choice. Then, the author shows you how you can use Twisted to make TCP connections to servers, and how to write a server that accepts TCP connections from clients. He continues by showing you how to use Twisted to work with the Web. Next, the author shows you how you can design a Twisted web application for programmatic accessing using the REST architectural style. Then he discusses the Twisted authentication framework, which provides an extremely flexible approach to authenticating users against different backends. He also demonstrates Twisted's powerful support for mail clients and servers. Then, he discusses Usenet clients and servers using the NNTP protocol. The author continues by covering Twisted's support for SSH. Finally, the author shows you how to use the tools Twisted provides for running and managing applications, which give you the ability to run daemon processes, use setuid and chroot to limit permissions, and write log files.

The goal of this most excellent book is to focus on practical examples of how to use Twisted to perform some of the most common tasks that face developers building network applications. More importantly, this book will help you to understand the key concepts and design patterns used in Twisted applications.

Abe Fettig's Twisted: Network Programming Essentials provides insights on the open source network application framework written in Python. Twisted offers Python programmers a powerful flexible option, producing programs which won't lock up and which are event driven by network events. Its stability and reliability lends to a program which is versatile, very easy for programmers to manipulate, and which can be used to write a web server, enable applications via email, and more. Review the program's strengths with this bible of advice in hand.

As the previous reviewers stated, there are errors and not deep explaination. The value of the books is in the examples and as an outline to a course of study.

Without Dive into Python by Mark Pilgram I would not have a chance with the Twisted book. Dive into Python is probably the second Python book for most people.

The asynchronous program technique of "Deferred"s explaination in the book and on the web site did help a little but left me unsure about details. Fortunately, the twisted source code is understandable. Essentially, a list of nested tuples is being managed. There are some pretty compact code, such as, for deferred chain, etc. so this route will require some confidence with Python.

My ubuntu Linux system has great Python support (this is not generally known - my discovery was by accident). Unbuntu 5.10 comes with Python 2.4.2 already installed. All the Pthon libraries needed for this book are ready for easy installation with the Synaptic package manager.

SPE (Stanni's Python Editor) is available on Ubuntu. It works out well for browsing the Twisted source code. The Python code is syntax colored, the classes and methods show up in the side bar for easy navigation, and there is a recusive find in files to track down references. It did do stange things once and a while -I will stick to VIM for editing my own programs.

Fedora, Mac OS X, and Windows probably require a little more work.

It seems to me the real Pythonistas go to the source and fussy documenation is for wimps. However, relative newbies like me can sure appreciate all the help they can get. This is a valuable book.

When Twisted started to explode onto the scene, I was really intrigued by its varied capabilities and asynchronous model, but I was turned off by the then-scant documentation and the webapp framework transition that was just beginning (Woven was deprecated and Nevow was too new for any sort of coherent explanation). I just didn't have time to wrap my head around it, and so Twisted fell off my radar screen for a while. Eventually, I saw that a book was on the way, and I was excited to jump back in with it as my guide.

Twisted Network Programming Essentials is not an exhaustive reference to Twisted, nor does it even pretend to be. Rather, it's a pretty friendly, task-oriented exploration, providing examples of common tasks and insight into the key concepts and design patterns that are essential to grokking Twisted. Each chapter focuses on a particular topic, and they're arranged to build upon each other nicely. Sections within each chapter are broken down into a practical, easily digested structure--we're introduced to the task at hand, then the "How do I do that?" and "How does it work?" bits clearly and plainly walk us through an example solution and dissect its inner workings. At 202 pages of actual text, its eleven chapters make for a comfortable chapter-per-evening of reading and play. It's well worth either keying in or downloading the example code to see Twisted in action.

Covered topics include installing Twisted, the essential Twisted concepts; HTTP clients and servers; RPC; authentication; mail clients and servers (POP and IMAP); NNTP clients and servers; fun with SSH; and some practical, non-glamorous things like running your app as a proper daemon, adding administrative interfaces, and logging. You'll monitor download progress, make a simple blog, build an IMAP server, and more. You'll chain protocols together to make an email interface to Google. You'll be impressed by the power and cleanliness of Twisted's authentication model, and you'll have fun getting and using references to remote Python objects with Perspective Broker. There's also a pretty good explanation of REST, and plenty of links to useful reading.

All is unfortunately not shiny and delicious, though. I encountered what I consider quite a few programming errors in the example code, as well as several places where the explanatory text doesn't quite jive with the example. These errors are all fairly minor, and are probably artifacts of the evolution of the text and examples, but the frequency with which they crop up suggested that either no one had run the code before approving it for printing, or that errors were deliberately introduced to see if the reader is paying attention. As someone with a professional investment in web applications and frameworks, I was disappointed not to see any investigation of Nevow (not stable enough at the time of writing to be included, alas). The SSH chapter mentions but does not discuss or dive into the file transfer and connection tunneling concepts. I was also let down by the strict focus on programs that only used the basic Twisted reactor for managing events--the challenge of integrating Twisted's powerful capabilities into an existing event-driven program (eg, any GUI app) is entirely omitted. Furthermore, the book ends somewhat suddenly; I would have welcomed a "Great! What now?" sort of wrap-up that would provide a guidepost to more advanced topics.

These warts are quite forgiveable, however, and will hopefully be corrected in a future revision. The book is clean, friendly, and clear, and provides a nice entry into the world of Twisted. We are neither talked down to, nor beaten into submission by overly dense, inscrutable prose. For this printing, keep the errata handy to quickly resolve any issues with the example code (and submit anything new that you find). While the topics might be considered limited, it's clear that what's here is the tip of the iceberg; you can use these familiar topics to try to sell your boss on Twisted, and then your imagination is the only limit to what you can do. Since my initial experience with Twisted, the core documentation has improved immensely, but it's even stronger if you're already familiar with what's presented here; start with this book, then dive on into the online docs, and you'll be a Twisted guru in no time.

The book is a cookbook of twisted based clients and servers, with
almost no material on twisted's core concepts (e.g., as noted in a
previous review, almost nothing about Zope3 interfaces.) Also very
little use of object oriented ideas and visualizations (there is
one interaction diagram in the book), even those central to twisted
like reactor. Also some of the more subtle issues important to
writing real systems, like event loop bridges to GUI toolkits,
multiple threads, or exception handling, are not covered. As a
cookbook it is useful in helping one get running examples going
quickly (somewhat like the online POE cookbook does for POE novices.)
But a twisted fundamental concepts book still remains to be written.

This is the documentation I've been waiting for to start learning Twisted. I originaly looked at Twisted a while back, but the documentation on the Twisted site was not helpful to me in learning how to get it all setup, working, and run a few examples. This book though does all this and more. I like the author's style of writting and theres no doubt that this book will be my de facto guide now for integrating Twisted into my software solutions.

Check out the table of contents: The chapters are Getting Started, Building Simple Clients and Servers, Web Clients, Web Servers, Web Services and RPC, Authentication, Mail Clients, Mail Servers, NNTP Clients and Servers, SSH, and finally Services, Processes, and Logging.

That's a lot of distinct subjects in a two-hundred page book. The result is a good demonstration of how broad Twisted's domain is, but the chapters, for the most part, do not build on one another. While that allows you to skip the chapter on news servers and read the SSH chapter without much difficulty, it also means you're getting lots of separate chunks of knowledge that don't add up to anything greater than the sum of their parts.

I was hoping to see more material on general topics that apply to all Twisted programs. Interfaces are one example. Interfaces, as used in Twisted, are not a part of the Python standard library and I would not assume a reader to be familiar with them. But while Interfaces do come up in a number of the examples, nowhere does the author take the time to explain why you're importing from zope.interface or how and where Twisted uses them. Yes, there are examples, but nothing to help you understand the theory for when you have to write your own code.

Nowhere do we learn how to write tests for asynchronous functions. While the last chapter touches on the organization of services in a Twisted application, it fails to note basics like what method you'd want to implement to run tasks during a graceful shutdown. In all the attention to different network protocols, the framework aspect of Twisted seems to have been neglected.

So overall, if you want to embed an email server in your application, this book will give you a place to start. If you want a hard copy text to demonstrate the range of applications Twisted can reach, this book will do that. But if your main concern is that Twisted makes your head hurt and you want someone to make it seem less alien, I'm not sure this is the book you've been waiting for.