Source code and other support files for Data Push Applications Using HTML5 SSE (published by O'Reilly, ISBN: 1449371930)
All the files are in the listings/ directory.
The listings directory could be served directly to your Apache server. There is a ".htaccess" file included to restrict access to one script (show_phpinfo.php) that shows server information; the other entries are for experimenting with the ways to do authentication.
A good place to start is listings/evolution.txt, which shows how the files relate to each other, and the order in which they develop, and how that ties in with the chapters in the book.
At the moment listings/readme.txt just covers the code conventions.
Contributions that show the back-end code ported to other server-side languages would be very welcome. Ideally it would require no change in the front-end (*.html) files, beyond changing the URL they connect to.