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Derek Comartin

Testing WITHOUT Mocks or Interfaces!

A common approach people take with testing is mocking. Specifically defining interfaces for dependencies which are then typically mocked so you can test in isolation. While interfaces can be helpful for mocking as well as fakes and stubs, there can be other approaches taken. Meaning you don’t need to create an interface for everything. YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Deterministic Let’s start with a method in an OrderService for creating an Order. To test this method, there are a few dependencies involved. The… Read More »Testing WITHOUT Mocks or Interfaces!

Domain Events in Event Sourcing? Not Exactly!

What are domain events for? Domain Driven Design and Event Driven Architecture are nothing new, but they continue to become more popular. Unfortunately, some concepts and terms get a bit murky as they do. Specifically, the term domain events have caused a bit of confusion. I will clarify a misconception about the role and purpose of domain events and how that relates to Event Sourcing. Or does it? YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Event Sourcing As a primer on Event Sourcing, it’s a… Read More »Domain Events in Event Sourcing? Not Exactly!

The Challenge of Microservices: UI Composition

One of the most challenging aspects of distributed applications like microservices is UI Composition. How to combine all the data from various services for your UI. I’m going over a few different solutions and their pros and cons for UI Composition and ViewModel Composition. YouTube Check out my YouTube channel, where I post all kinds of content accompanying my posts, including this video showing everything in this post. Multiple Sources When you’re working within a monolith and a single database, we don’t have the issue of compositing data. We get all the data we need from the single source database. As an… Read More »The Challenge of Microservices: UI Composition