Mastering Clean Architecture

Clean architecture is all about putting your domain at the center of the universe. The framework, the database, and the UI are just details.

The Layers

1. Domain: Entities, Enums, Exceptions, and Interfaces.
2. Application: Use Cases, CQRS Commands/Queries, and DTOs.
3. Infrastructure: Database Contexts, External API Clients, and Services.
4. Web/API: Controllers, Middlewares, and Views.

By structuring our ASP.NET Core projects this way, we make our business logic independently testable without spinning up a database.

public class CreatePostCommandHandler : IRequestHandler<CreatePostCommand, Guid>
{
    public async Task<Guid> Handle(CreatePostCommand request, CancellationToken cancellationToken)
    {
        // Business logic here
        return Guid.NewGuid();
    }
}

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