I had a chance to read a book named CherryPy Essentials 
with sub-title „Rapid Python Web Application Developments - Design, develop, test, and deploy your Python web applications easily“, author Sylvain Hellegouarch. The book has been issued in March 2007 by the Packt Publishing in their „From Technologies to Solutions“ edition.
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I had a chance to read a book named CherryPy Essentials with sub-title „Rapid Python Web Application Developments - Design, develop, test, and deploy your Python web applications easily“, author Sylvain Hellegouarch. The book has been issued in March 2007 by the Packt Publishing in their „From Technologies to Solutions“ edition.
I have to say I was enjoying that book. I was looking forward to a book in English, after all that sad experience with Czech books, translated from English originals, full of objective or stylistic mistakes (Computer Press is the worst example for such terrible behaviour).
As you maybe know, I don’t like e-books. I love to take the book with me everywhere I am - into the train, on my vacations, in the bed (mainly in the bed; I enjoy the book in the bed more than in another place). When I was looking for a framework and a language for development a short time ago, Python and its add-on libraries was as one of the most mentioned candidates. So when I could read a new book about Python library CherryPy, I didn’t hesitate.
The CherryPy Essentials book has been edited by Packt Publishing. Packt is a relatively new publisher; the first book was published in 2004. The Packt Publishing focuses mainly on books for developers, open-source software and modern programming techniques and tools.
The book I’m writing about begins with two (fortunately short) chapters with obligatory things such as „What is the CherryPy, where it comes from, how I can install it, what I find inside...“ The third chapter, CherryPy Overview, starts immediately with an example - listing of the source code of a simple CherryPy application, Notes. The author illustrates the basic work with the CherryPy on this example: Where put the files, how to start testing HTTP server, how to configure it, what is the principle of Object Publisher Engine; he talks about the CherryPy modules and tools and shortly describes the exceptions and errors engine. There is too much information, concentrated in a small area. I have to accord that I was really confused after reading this chapter and wanted to start reading something else, more interesting, at that moment, such as the Yellow Pages.
My confusion was fortified in the Chapter Four. That chapter begins with information about the HTTP implementation in the CherryPy - and my confusion reached its maximum at the moment I saw a server binding at the TCP/IP port 100100. In the next paragraph even „binding at the port 100100 and IP address 1102.168.0.12“ appeared. I thought I surely omitted some important information about the special number format in the CherryPy, so I read through the previous chapters again but found nothing. I read on, confused, and finally I found an example where „encoding ISO-88510-15“ was used. Hooray, it got across to me! Some bad goblin replaced all occurrences of the character „9“ with the string „10“. So the mystical address „1102.168...“ is the old, well known IP 192.168... and the port 100100 is nothing special but the ordinary port 9090. Maybe some innovative nine-based number system, who knows...
There is some more information about the CherryPy Toolbox in the rest of the chapter (no nines, fortunately). The author describes the tools contained in the CherryPy which a developer can use, with description of arguments and demonstration on examples. The chapter ends with a description of serving the static files (CSS etc.) and using the WSGI with the CherryPy.
The fifth chapter starts with a design of a practical example - Photoblog app. This example is a common part of the rest of the book. The author illustrates all the parts of application development on this example. There are entities used in the Photoblog described first, such as their roles, attributes and relations. The chapter continues with information about DBMS, describing the basic principles of RDBMS, ODBMS and XMLDBMS database engines with special attention paid to ORM. The author describes three ORM tools for Python - SQLObject, SQLAlchemy and Dejavu - and shows the basic operations with the database in each of that three tools. He compares these tools and demonstrates creating of the ORM for the Photoblog at the end.
The chapter number six has the title „Web Services“ and contains, how else, the description of the REST model and protocol. The REST is the standard protocol for data accessing over internet via well known HTTP methods. This chapter focuses on the implementation of the REST in the CherryPy and mentions the implementation of the publication protocol ATOM too. It is a very interesting and useful overview for the programmers using other systems or languages too.
The seventh chapter shows the issues the data presentation is about in the CherryPy: (X)HTML, CSS, the Kid template engine and the JS library Mochikit. The Photoblog example puts all these together in the Chapter Seven.
Only four letters „AJAX“ contains the title of the eighth chapter. This chapter puts one’s mind to the AJAX very deeply on its twenty six pages. In the chapter there are for example: XHR description, GET and POST requirements via XHR demonstration or authentization schemes Basic and Digest. The chapter continues with the demonstration of the login dialog implementation in the CherryPy, followed by the JSON format description. The AJAX theme ends with a concatenation of the previous chapters’ information to a one big thing - the AJAX-based, RESTified dialog for the new album creation in the CherryPy with the Mochikit.
The author shows the application testing in the Chapter Nine. He shows the usage of the tools like unittest, doctest or webtest, as so as the load testing or the functional testing with the Selenium tool.
And finally - in the last chapter named „Deployment“ one can find some information about application deployment, such as possibilities of CherryPy application installation on the web server with the Apache+mod_rewrite or with the Lightppd+mod_proxy as well as the Apache and mod_python combination. This chapter contains also information about SSL and configuration methods.
So - the verdict!
At the first place I have to say I haven’t started writing my applications in the CherryPy. But now I know very well what I’ll take if I must deal with some CherryPy app. Nevertheless the book was very useful for me, really. The first part of the book (about 90 pages) is something like „reference and quickstart“, very closely focused on the CherryPy. The information here is provided very consistently and its briefness may lead to less comprehensibility. But the rest of the book (about 160 pages) is very interesting and useful not only for the
CherryPy or the Python programmers, but for everyone interested in the modern web application development across the different languages.
The book is oscillating between a common description of web apps techniques and a (relatively short) description of implementation these techniques in the CherryPy. But on the other side this way makes the book interesting for developers not strictly interested in the CherryPy too. It’s always interesting to look outside of the box and take inspiration from the methods or the tools from the other worlds, isn’t it? The dark side of the book is that shameful mistake in the Chapter Four - this mistake is very misleading and, unfortunately, occurs in a heavy part of the book. Some things are neither positive nor negative. E.g. information about mod_python for the Apache server: The beginner evaluates positively that there is only few information, but all he needs for start the mod_python with Apache. But if you are an advanced user, you will probably look for some additional information, such as „what to do if some error occurs“ or „why I have to do this, what does it mean and what happens if I’ll try ...?“
I primarily write in PHP, but the chapters 5, 6 and 9 strongly hold my interest and inspirate me. The chapters 7, 8 and 10 are interesting for me too, so don’t worry about this book.
If I have to assign the stars to the CherryPy Essentials book, it should be rated by seven stars out of ten.
The book costs is 35.99 US dollars (27 US dollars for book in PDF format). If you order the book directly from the Packt Publishing e-shop , you have the shipping free of charge to the Czech Republic (as well as anywhere in the EU). You’ll get a handbook which shows the application development with CherryPy and provides an interesting roundup about the modern techniques used in the web development to you. I can unambiguously recommend this book to everyone developing the web apps in Python, but not only to them. This book will be interesting for people not using Python too to discover how the things work in another language.
Thanks to Packt Publishing for providing this book.
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