dotnet-http-client

Prevent HttpClient socket exhaustion in .NET by using IHttpClientFactory to manage client lifetimes, ensuring proper socket reuse and avoiding DNS staleness in long-running applications.

The best way to configure resilience for .NET HTTP API calls is using Microsoft.Extensions.Http.Resilience, which provides automatic retries, timeouts, and circuit breakers when consuming APIs via IHttpClientFactory.

Add custom authentication or logging to a typed HttpClient by implementing DelegatingHandler chains, which intercept requests to inject cross-cutting concerns like correlation IDs before the response returns.

Use typed clients with IHttpClientFactory to encapsulate API logic within a dedicated class, or use named clients when consuming multiple distinct APIs requiring different configurations within the same application.

Unit test an API client using IHttpClientFactory by mocking the underlying HTTP transport, verifying that your DelegatingHandler chains and typed client logic correctly process the returned HTTP responses.

HttpClient experiences stale DNS changes because its underlying handler caches DNS entries; using IHttpClientFactory rotates handler instances automatically to refresh DNS records and prevent connection failures.