Flask Framework Cookbook - Second Edition

Creating a modular web app with blueprints

A blueprint is a concept in Flask that helps make large applications really modular. This keeps application dispatching simple by providing a central place to register all components in an application. A blueprint looks like an application object but is not an application. It also looks like a pluggable app, or a smaller part of a bigger app, but it is not. A blueprint is actually a set of operations that can be registered on an application and represents how to construct or build an application.