dotnet-integration-testing

Integration testing for an ASP.NET Core API uses WebApplicationFactory to send HTTP requests in-process without network overhead, validating your application logic directly against the configured pipeline.

Testing a .NET web API against a live PostgreSQL database is best achieved by combining WebApplicationFactory for in-process HTTP requests with Testcontainers to spin up an isolated, disposable PostgreSQL instance in Docker.

Yes, .NET Aspire testing utilities orchestrate multi-service application testing, while Testcontainers provides disposable infrastructure like databases and message brokers in Docker containers for test isolation.

Yes, Testcontainers requires Docker to provision real infrastructure components, and the testing patterns require a .NET 8.0+ baseline along with Testcontainers 3.x+ and .NET Aspire 9.0+ if using Aspire utilities.

Database fixture management and test isolation in .NET integration tests are handled by spinning up disposable infrastructure via Testcontainers, ensuring each test run interacts with a clean, real database instance.

Using Testcontainers instead of mocks for .NET integration testing spins up real databases and message brokers in Docker, ensuring your application functions correctly in a production-like environment rather than against simulated dependencies.