Filtering Datastore entities while downloading data via Bulkloader

[Mikhail Dubov]

Hello,

Just read an article on how to download data from AppEngine Datastore:

https://developers.google.com/appengine/docs/python/tools/uploadingdata

Is the post_export_function, as described in the article, the only way to implement Custom Logic? The problem is that, as far as I can see, the entities get filtered only after they are downloaded by the Bulkloader, that is, on the client side (that's why the function is called post export). This process is rather slow, though. Is there a possibility to perform that filtering on the server? Something like "pre_export_function"?

Thank you,

Mikhail