Summary
In this section, we have completed our Wordz application. We used an integration test with TDD to drive out an HTTP endpoint for Wordz. We used open source HTTP libraries – Molecule, Gson, and Undertow. We made effective use of hexagonal architecture. Using ports and adapters, these frameworks became an implementation detail rather than a defining feature of our design.
We assembled our final application to bring together the business logic held in the domain layer with the Postgres database adapter and the HTTP endpoint adapter. Working together, our application forms a small microservice.
In this final chapter, we have arrived at a small-scale yet typical microservice comprising an HTTP API and a SQL database. We’ve developed the code test first, using tests to guide our design choices. We have applied the SOLID principles to improve how our software fits together. We have learned how the ports and adapters of hexagonal architecture simplify the design...