MessageHandler.cs

using System;
using System.Net.Http;
using System.Net.Http.Json;
using System.Threading;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    public class ProblemDetailsHttpMessageHandler : DelegatingHandler
    {
        public ProblemDetailsHttpMessageHandler() : base(new HttpClientHandler()) { }

        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken ct)
        {
            var response = await base.SendAsync(request, ct);

            var mediaType = response.Content.Headers.ContentType?.MediaType;
            if (mediaType != null && mediaType.Equals("application/problem+json", StringComparison.InvariantCultureIgnoreCase))
            {
                var problemDetails = await response.Content.ReadFromJsonAsync<ProblemDetails>(null, ct) ?? new ProblemDetails();
                throw new ProblemDetailsException(problemDetails, response);
            }

            return response;
        }
    }
}