Thanks to App Engine, we have already implemented a rich set of features with a relatively small effort so far.

In this chapter, we have discovered some more details about the webapp2 framework and its capabilities, implementing a nontrivial request handler. We have learned how to use the App Engine users service to provide users authentication. We have delved into some fundamental details of Datastore and now we know how to structure data in grouped entities and how to effectively retrieve data with ancestor queries. In addition, we have created an HTML user interface with the help of the Jinja2 template library, learning how to serve static content such as CSS files.

In the next chapter, we will keep on adding more and more features to the Notes application, learning how to store uploaded files on Google Cloud Storage, manipulate images, and deal with long operations and scheduled tasks. We will also make the application capable of sending and receiving e-mails.