C# / ASP.NET Core

Convenzioni, pattern e riferimenti tecnici per lo sviluppo con C# e ASP.NET Core.

Contenuto

1. Struttura della solution — organizzazione dei progetti, naming, Program.cs minimal
2. Switch expression e pattern matching — switch expression, pattern matching, when guard
3. Rate limiting — Microsoft.AspNetCore.RateLimiting, policy, sliding window
4. Feature flag — Microsoft.FeatureManagement, flag condizionali, targeting
5. Logging — ILogger<T>, Serilog, sink, log strutturati
6. Osservabilità — OpenTelemetry, trace, metriche, health checks
7. Configurazione tipizzata — IOptions<T>, IOptionsMonitor<T>, validazione
8. Code native .NET — Queue<T>, ConcurrentQueue<T>, Channel<T>
9. Librerie per code e job — Hangfire, Quartz.NET
10. Middleware custom — pipeline, RequestDelegate, gestione errori globale
11. Action filter — IActionFilter, IAsyncActionFilter
12. Authorization filter — IAuthorizationFilter, API key, tenant
13. Exception filter — IExceptionFilter, IAsyncExceptionFilter
14. Problem Details (RFC 9457) — errori strutturati, ProblemDetails, ValidationProblemDetails
15. Async / Await — throughput nelle Web API, CancellationToken, anti-pattern
16. Dependency Injection — lifetimes, captive dependency, keyed services
17. HttpClient / IHttpClientFactory — typed client, DelegatingHandler, socket exhaustion
18. Validazione — DataAnnotations, FluentValidation, ValidationProblemDetails
19. Background services — BackgroundService, worker pattern, graceful shutdown
20. Caching — IMemoryCache, IDistributedCache, output caching
21. Resilienza — retry, circuit breaker, timeout con Microsoft.Extensions.Http.Resilience
22. Records e immutabilità — record, with expression, DTO e value object

Entity Framework

• Code First — Setup e migration — DbContext, registrazione, Fluent API, migration CLI
• IQueryable vs List — esecuzione differita, N+1, AsNoTracking
• LINQ con Entity Framework — proiezioni, paginazione, Include, SQL grezzo

Test unitari

• A cosa servono — logica pura, monitoraggio librerie di terze parti, verifica di comportamenti puntuali

Test di integrazione

• Pattern: template e scope — classe base NUnit, clone da template, scope DI per test
• Scrivere un test — Get<T>(), SeedAsync, FluentAssertions, parallelismo
• Testcontainers — PostgreSQL in Docker, nessuna dipendenza locale