Errata

Thanks for the book, its a good one!

Near the top of page 288, this line:

"You provide the name of the file that defines the exporters using the --filename=... command-line argument"

...should instead read:

"You provide the name of the file that defines the exporters using the --config_file=... command-line argument"

Note from the Author or Editor:
Thanks! You are correct, this instance of "--filename" (first paragraph of page 288) should be "--config_file". (The --filename argument is for the data file.)

App Engine has heavily revised the bulk data loader tool since the 1st edition of this book was published. The Loader/Exporter interface has been deprecated in favor of a config-based declarative syntax for defining mappings. I recommend going to the official documentation on Google's website the latest information: http://code.google.com/appengine/docs/python/tools/uploadingdata.html

The first

multipart.addBodyPart(htmlPart)

should be

multipart.addBodyPart(textPart)

There seem to be some issues with this code sample. A 'cacheSet' method is referenced in the text but not in the code, the save() method does not update the cache as described, and I get an 'EntityExistsException' thrown from save() [on form submit] when I add the memcache functionality. (It would be great to get the code posted online, to be able to rule out code transcription errors when debugging).

Bottom row of figure 5-14 says

e2 3.14

But I think it is supposed to be

e1 3.14

So far great book, much better than google's online docs.

However, figure 5-10 and 5-11 seem like they are incorrect. They claim to show the results of a query that uses 'level < 10'. I think what they are showing is a query that uses 'level > 10'.