Nullables Livestream #3: Fetcher Nullability

In this weekly livestream series, I pair up with Ted M. Young, aka jitterted, to look at Nullables and A-Frame Architecture as an alternative to Mocks, Spies, and Hexagonal Architecture. Each episode combines a healthy dose of architecture and design discussion with hands-on coding.

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In this episode...

We start our work on the HttpAverageScoreFetcher and HttpScoreCategoryNotifier classes. These adapters are part of Ted’s implementation of Hexagonal Architecture: they retrieve and store data from a separate “Yacht Tracker” service. We spend some time understanding how hexagonal architecture works, then make HttpAverageScoreFetcher nullable. Along the way, we demonstrate the plusses—and minuses!—of using an embedded stub.

Visit the episode archive for more.

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