Replace the default Swashbuckle with NSwag to generate OpenAPI specifications for a new .NET web application.
Configure the project file to automatically run the NSwag command-line tool after each build to create an up-to-date swagger.json file.
Use the generated swagger.json file to automatically create a strongly-typed C# HTTP client within the test project.
Write API-level tests that consume the generated client, ensuring that any API signature changes result in compile-time errors.
Leverage the generated client and DTOs to easily test complex validation rules, serialization formats, and API exception handling.
Focusing on API-level tests provides high code coverage and confidence for refactoring while reducing the effort spent on traditional unit tests.
This approach requires writing precise controller code and evolving from slow Docker-based databases to faster in-memory databases for tests.
API-level tests reduce the developer time spent writing and maintaining numerous small unit tests, especially as the codebase grows.
Set a high but realistic code coverage target like 90-95% to avoid writing useless tests for unreachable edge cases.
A potential improvement is to add a CI step that tests the new API version against a client generated from a previous API version.
Use the web application factory to manage test setup, such as spinning up an in-memory database and seeding it with data for each test class.
Isolate the API under test by mocking external service calls through interfaces, reserving full integration tests for the CI pipeline.
The idea to use the generated client in tests originated from the initial goal of providing an easy-to-use client for other consumer APIs.
Wilken GmbH
Ulm, Germany
43:07Golo Roden
30:55Alex Banul
45:24Evelyn Haslinger
42:34Ryan Latta
47:22Christian Kühn
29:31Johannes Bergsmann & Daniel Bauer
26:02Vincent Hennig & Anupam Krishnamurthy
25:38Ramona Schwering
Jobs that call for the skills explored in this talk.
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DEKRA AG
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primion Technology GmbH
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