iot/projects/Infrastructure/Extensions/HttpClientExtensions.cs

using System.Linq;
using System.Net;
using System.Net.Http;

namespace Infrastructure.Extensions
{
    public static class HttpClientExtensions
    {
        public static byte[] GetByteDigest(this HttpClient httpClient, string url, string userName, string password)
        {
            return httpClient.GetDigest(url, userName, password).ReadAsByteArrayAsync().Result;
        }

        public static HttpContent GetDigest(this HttpClient httpClient, string url, string userName, string password)
        {
            var task = httpClient.GetAsync(url);
            var result = task.Result.Content;
            if (task.Result.StatusCode == HttpStatusCode.Unauthorized)
            {
                var dictionary = task.Result.Headers.GetValues("WWW-Authenticate").ToList().SelectMany(o => o.Split(',')).ToDictionary(o => o.Split('=')[0].Trim(), o => o.Split('=')[1].Trim().Trim('"'));
                var hc2 = new HttpClient();
                var realm = dictionary["realm"];
                var nonce = dictionary["nonce"];
                var qop = dictionary["Digest qop"];
                var uri = url.Substring(7).Substring(url.Substring(7).IndexOf('/'));
                var cnonce = nonce;
                var ha1 = $"{userName}:{realm}:{password}".Md5();
                var ha2 = $"GET:{uri}".Md5();
                var nc = "00000001";
                var response = $"{ha1}:{nonce}:{nc}:{cnonce}:{qop}:{ha2}".Md5();
                var authorization = $"Digest username=\"{userName}\",realm=\"{realm}\",nonce=\"{nonce}\",uri=\"{uri}\",cnonce=\"{cnonce}\",nc={nc},response=\"{response}\",qop=\"{qop}\"";
                hc2.DefaultRequestHeaders.Add("Authorization", authorization);
                var task2 = hc2.GetAsync(url);
                result = task2.Result.Content;
            }
            return result;
        }
    }
}