Use modern HttpClient

Co-Authored-By: ta264 <ta264@users.noreply.github.com>

.editorconfig

@@ -262,7 +262,6 @@ dotnet_diagnostic.CA5394.severity = suggestion
 dotnet_diagnostic.CA5397.severity = suggestion
 
 dotnet_diagnostic.SYSLIB0006.severity = none
-dotnet_diagnostic.SYSLIB0014.severity = none
 
 [*.{js,html,js,hbs,less,css}]
 charset = utf-8

src/NzbDrone.Common.Test/Http/HttpClientFixture.cs

@@ -4,6 +4,7 @@ using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using System.Threading;
 using FluentAssertions;
 using Moq;
@@ -15,12 +16,14 @@ using NzbDrone.Common.Http;
 using NzbDrone.Common.Http.Dispatchers;
 using NzbDrone.Common.Http.Proxy;
 using NzbDrone.Common.TPL;
+using NzbDrone.Core.Configuration;
+using NzbDrone.Core.Security;
 using NzbDrone.Test.Common;
 using NzbDrone.Test.Common.Categories;
+using HttpClient = NzbDrone.Common.Http.HttpClient;
 
 namespace NzbDrone.Common.Test.Http
 {
-    [Ignore("httpbin is bugged")]
     [IntegrationTest]
     [TestFixture(typeof(ManagedHttpDispatcher))]
     public class HttpClientFixture<TDispatcher> : TestBase<HttpClient>
@@ -32,39 +35,38 @@ namespace NzbDrone.Common.Test.Http
         private string _httpBinHost;
         private string _httpBinHost2;
 
+        private System.Net.Http.HttpClient _httpClient = new ();
+
         [OneTimeSetUp]
         public void FixtureSetUp()
         {
-            var candidates = new[] { "eu.httpbin.org", /*"httpbin.org",*/ "www.httpbin.org" };
+            // Always use our server for main tests
+            var mainHost = "httpbin.servarr.com";
+
+            // Use mirrors for tests that use two hosts
+            var candidates = new[] { "httpbin1.servarr.com" };
 
             // httpbin.org is broken right now, occassionally redirecting to https if it's unavailable.
+            _httpBinHost = mainHost;
             _httpBinHosts = candidates.Where(IsTestSiteAvailable).ToArray();
 
             TestLogger.Info($"{candidates.Length} TestSites available.");
 
-            _httpBinSleep = _httpBinHosts.Count() < 2 ? 100 : 10;
+            _httpBinSleep = 10;
         }
 
         private bool IsTestSiteAvailable(string site)
         {
             try
             {
-                var req = WebRequest.Create($"http://{site}/get") as HttpWebRequest;
-                var res = req.GetResponse() as HttpWebResponse;
+                var res = _httpClient.GetAsync($"https://{site}/get").GetAwaiter().GetResult();
+
                 if (res.StatusCode != HttpStatusCode.OK)
                 {
                     return false;
                 }
 
-                try
-                {
-                    req = WebRequest.Create($"http://{site}/status/429") as HttpWebRequest;
-                    res = req.GetResponse() as HttpWebResponse;
-                }
-                catch (WebException ex)
-                {
-                    res = ex.Response as HttpWebResponse;
-                }
+                res = _httpClient.GetAsync($"https://{site}/status/429").GetAwaiter().GetResult();
 
                 if (res == null || res.StatusCode != (HttpStatusCode)429)
                 {
@@ -91,10 +93,14 @@ namespace NzbDrone.Common.Test.Http
             Mocker.GetMock<IOsInfo>().Setup(c => c.Name).Returns("TestOS");
             Mocker.GetMock<IOsInfo>().Setup(c => c.Version).Returns("9.0.0");
 
+            Mocker.GetMock<IConfigService>().SetupGet(x => x.CertificateValidation).Returns(CertificateValidationType.Enabled);
+
             Mocker.SetConstant<IUserAgentBuilder>(Mocker.Resolve<UserAgentBuilder>());
 
             Mocker.SetConstant<ICacheManager>(Mocker.Resolve<CacheManager>());
             Mocker.SetConstant<ICreateManagedWebProxy>(Mocker.Resolve<ManagedWebProxyFactory>());
+            Mocker.SetConstant<ICertificateValidationService>(new X509CertificateValidationService(Mocker.GetMock<IConfigService>().Object, TestLogger));
+
             Mocker.SetConstant<IRateLimitService>(Mocker.Resolve<RateLimitService>());
             Mocker.SetConstant<IEnumerable<IHttpRequestInterceptor>>(new IHttpRequestInterceptor[0]);
             Mocker.SetConstant<IHttpDispatcher>(Mocker.Resolve<TDispatcher>());
@@ -105,8 +111,7 @@ namespace NzbDrone.Common.Test.Http
             //      .Returns(new HttpProxySettings(ProxyType.Socks5, "127.0.0.1", 5476, "", false));
 
             // Roundrobin over the two servers, to reduce the chance of hitting the ratelimiter.
-            _httpBinHost = _httpBinHosts[_httpBinRandom++ % _httpBinHosts.Length];
-            _httpBinHost2 = _httpBinHosts[_httpBinRandom % _httpBinHosts.Length];
+            _httpBinHost2 = _httpBinHosts[_httpBinRandom++ % _httpBinHosts.Length];
         }
 
         [TearDown]
@@ -118,7 +123,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_execute_simple_get()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
 
             var response = Subject.Execute(request);
 
@@ -135,10 +140,32 @@ namespace NzbDrone.Common.Test.Http
             response.Content.Should().NotBeNullOrWhiteSpace();
         }
 
+        [TestCase(CertificateValidationType.Enabled)]
+        [TestCase(CertificateValidationType.DisabledForLocalAddresses)]
+        public void bad_ssl_should_fail_when_remote_validation_enabled(CertificateValidationType validationType)
+        {
+            Mocker.GetMock<IConfigService>().SetupGet(x => x.CertificateValidation).Returns(validationType);
+            var request = new HttpRequest($"https://expired.badssl.com");
+
+            Assert.Throws<HttpRequestException>(() => Subject.Execute(request));
+            ExceptionVerification.ExpectedErrors(2);
+        }
+
+        [Test]
+        public void bad_ssl_should_pass_if_remote_validation_disabled()
+        {
+            Mocker.GetMock<IConfigService>().SetupGet(x => x.CertificateValidation).Returns(CertificateValidationType.Disabled);
+
+            var request = new HttpRequest($"https://expired.badssl.com");
+
+            Subject.Execute(request);
+            ExceptionVerification.ExpectedErrors(0);
+        }
+
         [Test]
         public void should_execute_typed_get()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/get?test=1");
+            var request = new HttpRequest($"https://{_httpBinHost}/get?test=1");
 
             var response = Subject.Get<HttpBinResource>(request);
 
@@ -151,7 +178,7 @@ namespace NzbDrone.Common.Test.Http
         {
             var message = "{ my: 1 }";
 
-            var request = new HttpRequest($"http://{_httpBinHost}/post");
+            var request = new HttpRequest($"https://{_httpBinHost}/post");
             request.SetContent(message);
 
             var response = Subject.Post<HttpBinResource>(request);
@@ -159,15 +186,42 @@ namespace NzbDrone.Common.Test.Http
             response.Resource.Data.Should().Be(message);
         }
 
-        [TestCase("gzip")]
-        public void should_execute_get_using_gzip(string compression)
+        [Test]
+        public void should_execute_post_with_content_type()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/{compression}");
+            var message = "{ my: 1 }";
 
+            var request = new HttpRequest($"https://{_httpBinHost}/post");
+            request.SetContent(message);
+            request.Headers.ContentType = "application/json";
+
+            var response = Subject.Post<HttpBinResource>(request);
+
+            response.Resource.Data.Should().Be(message);
+        }
+
+        [Test]
+        public void should_execute_get_using_gzip()
+        {
+            var request = new HttpRequest($"https://{_httpBinHost}/gzip");
             var response = Subject.Get<HttpBinResource>(request);
 
-            response.Resource.Headers["Accept-Encoding"].ToString().Should().Be(compression);
-            response.Headers.ContentLength.Should().BeLessOrEqualTo(response.Content.Length);
+            response.Resource.Headers["Accept-Encoding"].ToString().Should().Contain("gzip");
+
+            response.Resource.Gzipped.Should().BeTrue();
+            response.Resource.Brotli.Should().BeFalse();
+        }
+
+        [Test]
+        public void should_execute_get_using_brotli()
+        {
+            var request = new HttpRequest($"https://{_httpBinHost}/brotli");
+            var response = Subject.Get<HttpBinResource>(request);
+
+            response.Resource.Headers["Accept-Encoding"].ToString().Should().Contain("br");
+
+            response.Resource.Gzipped.Should().BeFalse();
+            response.Resource.Brotli.Should().BeTrue();
         }
 
         [TestCase(HttpStatusCode.Unauthorized)]
@@ -178,7 +232,7 @@ namespace NzbDrone.Common.Test.Http
         [TestCase(HttpStatusCode.BadGateway)]
         public void should_throw_on_unsuccessful_status_codes(int statusCode)
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/status/{statusCode}");
+            var request = new HttpRequest($"https://{_httpBinHost}/status/{statusCode}");
 
             var exception = Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
 
@@ -190,10 +244,10 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_throw_on_suppressed_status_codes()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
+            var request = new HttpRequest($"https://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
             request.SuppressHttpErrorStatusCodes = new[] { HttpStatusCode.NotFound };
 
-            var exception = Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
+            Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
 
             ExceptionVerification.IgnoreWarns();
         }
@@ -201,7 +255,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_log_unsuccessful_status_codes()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
+            var request = new HttpRequest($"https://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
 
             var exception = Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
 
@@ -211,10 +265,10 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_log_unsuccessful_status_codes()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
+            var request = new HttpRequest($"https://{_httpBinHost}/status/{HttpStatusCode.NotFound}");
             request.LogHttpError = false;
 
-            var exception = Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
+            Assert.Throws<HttpException>(() => Subject.Get<HttpBinResource>(request));
 
             ExceptionVerification.ExpectedWarns(0);
         }
@@ -222,7 +276,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_follow_redirects_when_not_in_production()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/redirect/1");
+            var request = new HttpRequest($"https://{_httpBinHost}/redirect/1");
 
             Subject.Get(request);
 
@@ -232,7 +286,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_follow_redirects()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/redirect/1");
+            var request = new HttpRequest($"https://{_httpBinHost}/redirect/1");
             request.AllowAutoRedirect = true;
 
             var response = Subject.Get(request);
@@ -245,7 +299,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_follow_redirects()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/redirect/1");
+            var request = new HttpRequest($"https://{_httpBinHost}/redirect/1");
             request.AllowAutoRedirect = false;
 
             var response = Subject.Get(request);
@@ -258,7 +312,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_follow_redirects_to_https()
         {
-            var request = new HttpRequestBuilder($"http://{_httpBinHost}/redirect-to")
+            var request = new HttpRequestBuilder($"https://{_httpBinHost}/redirect-to")
                 .AddQueryParam("url", $"https://sonarr.tv/")
                 .Build();
             request.AllowAutoRedirect = true;
@@ -274,7 +328,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_throw_on_too_many_redirects()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/redirect/6");
+            var request = new HttpRequest($"https://{_httpBinHost}/redirect/6");
             request.AllowAutoRedirect = true;
 
             Assert.Throws<WebException>(() => Subject.Get(request));
@@ -285,7 +339,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_send_user_agent()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
 
             var response = Subject.Get<HttpBinResource>(request);
 
@@ -299,7 +353,7 @@ namespace NzbDrone.Common.Test.Http
         [TestCase("Accept", "text/xml, text/rss+xml, application/rss+xml")]
         public void should_send_headers(string header, string value)
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
             request.Headers.Add(header, value);
 
             var response = Subject.Get<HttpBinResource>(request);
@@ -324,12 +378,30 @@ namespace NzbDrone.Common.Test.Http
             fileInfo.Length.Should().Be(307054);
         }
 
+        [Test]
+        public void should_download_file_with_redirect()
+        {
+            var file = GetTempFilePath();
+
+            var request = new HttpRequestBuilder($"https://{_httpBinHost}/redirect-to")
+                .AddQueryParam("url", $"https://sonarr.tv/img/slider/seriesdetails.png")
+                .Build();
+
+            Subject.DownloadFile(request.Url.FullUri, file);
+
+            ExceptionVerification.ExpectedErrors(0);
+
+            var fileInfo = new FileInfo(file);
+            fileInfo.Exists.Should().BeTrue();
+            fileInfo.Length.Should().Be(307054);
+        }
+
         [Test]
         public void should_not_download_file_with_error()
         {
             var file = GetTempFilePath();
 
-            Assert.Throws<HttpException>(() => Subject.DownloadFile("http://download.sonarr.tv/wrongpath", file));
+            Assert.Throws<HttpException>(() => Subject.DownloadFile("https://download.sonarr.tv/wrongpath", file));
 
             File.Exists(file).Should().BeFalse();
             File.Exists(file + ".part").Should().BeFalse();
@@ -344,7 +416,7 @@ namespace NzbDrone.Common.Test.Http
 
             using (var fileStream = new FileStream(file, FileMode.Create))
             {
-                var request = new HttpRequest($"http://{_httpBinHost}/redirect/1");
+                var request = new HttpRequest($"https://{_httpBinHost}/redirect/1");
                 request.AllowAutoRedirect = false;
                 request.ResponseStream = fileStream;
 
@@ -365,7 +437,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_send_cookie()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
             request.Cookies["my"] = "cookie";
 
             var response = Subject.Get<HttpBinResource>(request);
@@ -384,7 +456,7 @@ namespace NzbDrone.Common.Test.Http
                 Assert.Inconclusive("Need both httpbin.org and eu.httpbin.org to run this test.");
             }
 
-            var oldRequest = new HttpRequest($"http://{_httpBinHost2}/get");
+            var oldRequest = new HttpRequest($"https://{_httpBinHost2}/get");
             oldRequest.Cookies["my"] = "cookie";
 
             var oldClient = new HttpClient(new IHttpRequestInterceptor[0], Mocker.Resolve<ICacheManager>(), Mocker.Resolve<IRateLimitService>(), Mocker.Resolve<IHttpDispatcher>(), Mocker.GetMock<IUserAgentBuilder>().Object, Mocker.Resolve<Logger>());
@@ -401,7 +473,7 @@ namespace NzbDrone.Common.Test.Http
         {
             GivenOldCookie();
 
-            var request = new HttpRequest($"http://{_httpBinHost2}/get");
+            var request = new HttpRequest($"https://{_httpBinHost2}/get");
 
             var response = Subject.Get<HttpBinResource>(request);
 
@@ -417,7 +489,7 @@ namespace NzbDrone.Common.Test.Http
         {
             GivenOldCookie();
 
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
 
             var response = Subject.Get<HttpBinResource>(request);
 
@@ -427,14 +499,14 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_store_request_cookie()
         {
-            var requestGet = new HttpRequest($"http://{_httpBinHost}/get");
+            var requestGet = new HttpRequest($"https://{_httpBinHost}/get");
             requestGet.Cookies.Add("my", "cookie");
             requestGet.AllowAutoRedirect = false;
             requestGet.StoreRequestCookie = false;
             requestGet.StoreResponseCookie = false;
             var responseGet = Subject.Get<HttpBinResource>(requestGet);
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.AllowAutoRedirect = false;
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -446,14 +518,14 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_store_request_cookie()
         {
-            var requestGet = new HttpRequest($"http://{_httpBinHost}/get");
+            var requestGet = new HttpRequest($"https://{_httpBinHost}/get");
             requestGet.Cookies.Add("my", "cookie");
             requestGet.AllowAutoRedirect = false;
             requestGet.StoreRequestCookie.Should().BeTrue();
             requestGet.StoreResponseCookie = false;
             var responseGet = Subject.Get<HttpBinResource>(requestGet);
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.AllowAutoRedirect = false;
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -465,7 +537,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_delete_request_cookie()
         {
-            var requestDelete = new HttpRequest($"http://{_httpBinHost}/cookies/delete?my");
+            var requestDelete = new HttpRequest($"https://{_httpBinHost}/cookies/delete?my");
             requestDelete.Cookies.Add("my", "cookie");
             requestDelete.AllowAutoRedirect = true;
             requestDelete.StoreRequestCookie = false;
@@ -480,7 +552,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_clear_request_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestSet.Cookies.Add("my", "cookie");
             requestSet.AllowAutoRedirect = false;
             requestSet.StoreRequestCookie = true;
@@ -488,7 +560,7 @@ namespace NzbDrone.Common.Test.Http
 
             var responseSet = Subject.Get<HttpCookieResource>(requestSet);
 
-            var requestClear = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestClear = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestClear.Cookies.Add("my", null);
             requestClear.AllowAutoRedirect = false;
             requestClear.StoreRequestCookie = true;
@@ -502,14 +574,14 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_store_response_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies/set?my=cookie");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies/set?my=cookie");
             requestSet.AllowAutoRedirect = false;
             requestSet.StoreRequestCookie = false;
             requestSet.StoreResponseCookie.Should().BeFalse();
 
             var responseSet = Subject.Get(requestSet);
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
 
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -521,14 +593,14 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_store_response_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies/set?my=cookie");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies/set?my=cookie");
             requestSet.AllowAutoRedirect = false;
             requestSet.StoreRequestCookie = false;
             requestSet.StoreResponseCookie = true;
 
             var responseSet = Subject.Get(requestSet);
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
 
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -540,7 +612,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_temp_store_response_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies/set?my=cookie");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies/set?my=cookie");
             requestSet.AllowAutoRedirect = true;
             requestSet.StoreRequestCookie = false;
             requestSet.StoreResponseCookie.Should().BeFalse();
@@ -555,7 +627,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_overwrite_response_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies/set?my=cookie");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies/set?my=cookie");
             requestSet.Cookies.Add("my", "oldcookie");
             requestSet.AllowAutoRedirect = false;
             requestSet.StoreRequestCookie = false;
@@ -563,7 +635,7 @@ namespace NzbDrone.Common.Test.Http
 
             var responseSet = Subject.Get(requestSet);
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
 
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -575,7 +647,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_overwrite_temp_response_cookie()
         {
-            var requestSet = new HttpRequest($"http://{_httpBinHost}/cookies/set?my=cookie");
+            var requestSet = new HttpRequest($"https://{_httpBinHost}/cookies/set?my=cookie");
             requestSet.Cookies.Add("my", "oldcookie");
             requestSet.AllowAutoRedirect = true;
             requestSet.StoreRequestCookie = true;
@@ -585,7 +657,7 @@ namespace NzbDrone.Common.Test.Http
 
             responseSet.Resource.Cookies.Should().HaveCount(1).And.Contain("my", "cookie");
 
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
 
             var responseCookies = Subject.Get<HttpCookieResource>(requestCookies);
 
@@ -597,7 +669,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_not_delete_response_cookie()
         {
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.Cookies.Add("my", "cookie");
             requestCookies.AllowAutoRedirect = false;
             requestCookies.StoreRequestCookie = true;
@@ -606,14 +678,14 @@ namespace NzbDrone.Common.Test.Http
 
             responseCookies.Resource.Cookies.Should().HaveCount(1).And.Contain("my", "cookie");
 
-            var requestDelete = new HttpRequest($"http://{_httpBinHost}/cookies/delete?my");
+            var requestDelete = new HttpRequest($"https://{_httpBinHost}/cookies/delete?my");
             requestDelete.AllowAutoRedirect = false;
             requestDelete.StoreRequestCookie = false;
             requestDelete.StoreResponseCookie = false;
 
             var responseDelete = Subject.Get(requestDelete);
 
-            requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.StoreRequestCookie = false;
             requestCookies.StoreResponseCookie = false;
 
@@ -627,7 +699,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_delete_response_cookie()
         {
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.Cookies.Add("my", "cookie");
             requestCookies.AllowAutoRedirect = false;
             requestCookies.StoreRequestCookie = true;
@@ -636,14 +708,14 @@ namespace NzbDrone.Common.Test.Http
 
             responseCookies.Resource.Cookies.Should().HaveCount(1).And.Contain("my", "cookie");
 
-            var requestDelete = new HttpRequest($"http://{_httpBinHost}/cookies/delete?my");
+            var requestDelete = new HttpRequest($"https://{_httpBinHost}/cookies/delete?my");
             requestDelete.AllowAutoRedirect = false;
             requestDelete.StoreRequestCookie = false;
             requestDelete.StoreResponseCookie = true;
 
             var responseDelete = Subject.Get(requestDelete);
 
-            requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.StoreRequestCookie = false;
             requestCookies.StoreResponseCookie = false;
 
@@ -657,7 +729,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_delete_temp_response_cookie()
         {
-            var requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            var requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.Cookies.Add("my", "cookie");
             requestCookies.AllowAutoRedirect = false;
             requestCookies.StoreRequestCookie = true;
@@ -666,7 +738,7 @@ namespace NzbDrone.Common.Test.Http
 
             responseCookies.Resource.Cookies.Should().HaveCount(1).And.Contain("my", "cookie");
 
-            var requestDelete = new HttpRequest($"http://{_httpBinHost}/cookies/delete?my");
+            var requestDelete = new HttpRequest($"https://{_httpBinHost}/cookies/delete?my");
             requestDelete.AllowAutoRedirect = true;
             requestDelete.StoreRequestCookie = false;
             requestDelete.StoreResponseCookie = false;
@@ -674,7 +746,7 @@ namespace NzbDrone.Common.Test.Http
 
             responseDelete.Resource.Cookies.Should().BeEmpty();
 
-            requestCookies = new HttpRequest($"http://{_httpBinHost}/cookies");
+            requestCookies = new HttpRequest($"https://{_httpBinHost}/cookies");
             requestCookies.StoreRequestCookie = false;
             requestCookies.StoreResponseCookie = false;
 
@@ -686,7 +758,7 @@ namespace NzbDrone.Common.Test.Http
         [Test]
         public void should_throw_on_http429_too_many_requests()
         {
-            var request = new HttpRequest($"http://{_httpBinHost}/status/429");
+            var request = new HttpRequest($"https://{_httpBinHost}/status/429");
 
             Assert.Throws<TooManyRequestsException>(() => Subject.Get(request));
 
@@ -706,7 +778,7 @@ namespace NzbDrone.Common.Test.Http
                 .Setup(v => v.PostResponse(It.IsAny<HttpResponse>()))
                 .Returns<HttpResponse>(r => r);
 
-            var request = new HttpRequest($"http://{_httpBinHost}/get");
+            var request = new HttpRequest($"https://{_httpBinHost}/get");
 
             Subject.Get(request);
 
@@ -728,7 +800,7 @@ namespace NzbDrone.Common.Test.Http
             {
                 // the date is bad in the below - should be 13-Jul-2026
                 string malformedCookie = @"__cfduid=d29e686a9d65800021c66faca0a29b4261436890790; expires=Mon, 13-Jul-26 16:19:50 GMT; path=/; HttpOnly";
-                var requestSet = new HttpRequestBuilder($"http://{_httpBinHost}/response-headers")
+                var requestSet = new HttpRequestBuilder($"https://{_httpBinHost}/response-headers")
                     .AddQueryParam("Set-Cookie", malformedCookie)
                     .Build();
 
@@ -737,7 +809,7 @@ namespace NzbDrone.Common.Test.Http
 
                 var responseSet = Subject.Get(requestSet);
 
-                var request = new HttpRequest($"http://{_httpBinHost}/get");
+                var request = new HttpRequest($"https://{_httpBinHost}/get");
 
                 var response = Subject.Get<HttpBinResource>(request);
 
@@ -761,7 +833,7 @@ namespace NzbDrone.Common.Test.Http
         {
             try
             {
-                string url = $"http://{_httpBinHost}/response-headers?Set-Cookie={Uri.EscapeDataString(malformedCookie)}";
+                string url = $"https://{_httpBinHost}/response-headers?Set-Cookie={Uri.EscapeDataString(malformedCookie)}";
 
                 var requestSet = new HttpRequest(url);
                 requestSet.AllowAutoRedirect = false;
@@ -769,7 +841,7 @@ namespace NzbDrone.Common.Test.Http
 
                 var responseSet = Subject.Get(requestSet);
 
-                var request = new HttpRequest($"http://{_httpBinHost}/get");
+                var request = new HttpRequest($"https://{_httpBinHost}/get");
 
                 var response = Subject.Get<HttpBinResource>(request);
 
@@ -781,6 +853,17 @@ namespace NzbDrone.Common.Test.Http
             {
             }
         }
+
+        [Test]
+        public void should_correctly_use_basic_auth()
+        {
+            var request = new HttpRequest($"https://{_httpBinHost}/basic-auth/username/password");
+            request.Credentials = new BasicNetworkCredential("username", "password");
+
+            var response = Subject.Execute(request);
+
+            response.StatusCode.Should().Be(HttpStatusCode.OK);
+        }
     }
 
     public class HttpBinResource
@@ -790,6 +873,8 @@ namespace NzbDrone.Common.Test.Http
         public string Origin { get; set; }
         public string Url { get; set; }
         public string Data { get; set; }
+        public bool Gzipped { get; set; }
+        public bool Brotli { get; set; }
     }
 
     public class HttpCookieResource

src/NzbDrone.Common/Extensions/StringExtensions.cs

@@ -194,5 +194,26 @@ namespace NzbDrone.Common.Extensions
 
             return value;
         }
+
+        public static string EncodeRFC3986(this string value)
+        {
+            // From Twitterizer http://www.twitterizer.net/
+            if (string.IsNullOrEmpty(value))
+            {
+                return string.Empty;
+            }
+
+            var encoded = Uri.EscapeDataString(value);
+
+            return Regex
+                .Replace(encoded, "(%[0-9a-f][0-9a-f])", c => c.Value.ToUpper())
+                .Replace("(", "%28")
+                .Replace(")", "%29")
+                .Replace("$", "%24")
+                .Replace("!", "%21")
+                .Replace("*", "%2A")
+                .Replace("'", "%27")
+                .Replace("%7E", "~");
+        }
     }
 }

src/NzbDrone.Common/Http/BasicNetworkCredential.cs

@@ -0,0 +1,12 @@
+using System.Net;
+
+namespace NzbDrone.Common.Http
+{
+    public class BasicNetworkCredential : NetworkCredential
+    {
+        public BasicNetworkCredential(string user, string pass)
+        : base(user, pass)
+        {
+        }
+    }
+}

src/NzbDrone.Common/Http/Dispatchers/ICertificationValidationService.cs

@@ -0,0 +1,10 @@
+using System.Net.Security;
+using System.Security.Cryptography.X509Certificates;
+
+namespace NzbDrone.Common.Http.Dispatchers
+{
+    public interface ICertificateValidationService
+    {
+        bool ShouldByPassValidationError(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors);
+    }
+}

src/NzbDrone.Common/Http/Dispatchers/ManagedHttpDispatcher.cs

@@ -1,178 +1,234 @@
 using System;
 using System.IO;
-using System.IO.Compression;
 using System.Net;
-using System.Reflection;
+using System.Net.Http;
+using System.Net.Security;
+using System.Net.Sockets;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
 using NLog;
-using NLog.Fluent;
-using NzbDrone.Common.EnvironmentInfo;
+using NzbDrone.Common.Cache;
 using NzbDrone.Common.Extensions;
 using NzbDrone.Common.Http.Proxy;
-using NzbDrone.Common.Instrumentation.Extensions;
 
 namespace NzbDrone.Common.Http.Dispatchers
 {
     public class ManagedHttpDispatcher : IHttpDispatcher
     {
+        private const string NO_PROXY_KEY = "no-proxy";
+
+        private const int connection_establish_timeout = 2000;
+        private static bool useIPv6 = Socket.OSSupportsIPv6;
+        private static bool hasResolvedIPv6Availability;
+
         private readonly IHttpProxySettingsProvider _proxySettingsProvider;
         private readonly ICreateManagedWebProxy _createManagedWebProxy;
+        private readonly ICertificateValidationService _certificateValidationService;
         private readonly IUserAgentBuilder _userAgentBuilder;
-        private readonly IPlatformInfo _platformInfo;
+        private readonly ICached<System.Net.Http.HttpClient> _httpClientCache;
         private readonly Logger _logger;
+        private readonly ICached<CredentialCache> _credentialCache;
 
-        public ManagedHttpDispatcher(IHttpProxySettingsProvider proxySettingsProvider, ICreateManagedWebProxy createManagedWebProxy, IUserAgentBuilder userAgentBuilder, IPlatformInfo platformInfo, Logger logger)
+        public ManagedHttpDispatcher(IHttpProxySettingsProvider proxySettingsProvider,
+                                     ICreateManagedWebProxy createManagedWebProxy,
+                                     ICertificateValidationService certificateValidationService,
+                                     IUserAgentBuilder userAgentBuilder,
+                                     ICacheManager cacheManager,
+                                     Logger logger)
         {
             _proxySettingsProvider = proxySettingsProvider;
             _createManagedWebProxy = createManagedWebProxy;
+            _certificateValidationService = certificateValidationService;
             _userAgentBuilder = userAgentBuilder;
-            _platformInfo = platformInfo;
             _logger = logger;
+
+            _httpClientCache = cacheManager.GetCache<System.Net.Http.HttpClient>(typeof(ManagedHttpDispatcher));
+            _credentialCache = cacheManager.GetCache<CredentialCache>(typeof(ManagedHttpDispatcher), "credentialcache");
         }
 
         public HttpResponse GetResponse(HttpRequest request, CookieContainer cookies)
         {
-            var webRequest = (HttpWebRequest)WebRequest.Create((Uri)request.Url);
+            var requestMessage = new HttpRequestMessage(request.Method, (Uri)request.Url);
+            requestMessage.Headers.UserAgent.ParseAdd(_userAgentBuilder.GetUserAgent(request.UseSimplifiedUserAgent));
+            requestMessage.Headers.ConnectionClose = !request.ConnectionKeepAlive;
 
-            // Deflate is not a standard and could break depending on implementation.
-            // we should just stick with the more compatible Gzip
-            //http://stackoverflow.com/questions/8490718/how-to-decompress-stream-deflated-with-java-util-zip-deflater-in-net
-            webRequest.AutomaticDecompression = DecompressionMethods.GZip;
-
-            webRequest.Method = request.Method.ToString();
-            webRequest.UserAgent = _userAgentBuilder.GetUserAgent(request.UseSimplifiedUserAgent);
-            webRequest.KeepAlive = request.ConnectionKeepAlive;
-            webRequest.AllowAutoRedirect = false;
-            webRequest.CookieContainer = cookies;
+            var cookieHeader = cookies.GetCookieHeader((Uri)request.Url);
+            if (cookieHeader.IsNotNullOrWhiteSpace())
+            {
+                requestMessage.Headers.Add("Cookie", cookieHeader);
+            }
 
+            using var cts = new CancellationTokenSource();
             if (request.RequestTimeout != TimeSpan.Zero)
             {
-                webRequest.Timeout = (int)Math.Ceiling(request.RequestTimeout.TotalMilliseconds);
-            }
-
-            AddProxy(webRequest, request);
-
-            if (request.Headers != null)
-            {
-                AddRequestHeaders(webRequest, request.Headers);
-            }
-
-            HttpWebResponse httpWebResponse;
-
-            try
-            {
-                if (request.ContentData != null)
-                {
-                    webRequest.ContentLength = request.ContentData.Length;
-                    using (var writeStream = webRequest.GetRequestStream())
-                    {
-                        writeStream.Write(request.ContentData, 0, request.ContentData.Length);
-                    }
-                }
-
-                httpWebResponse = (HttpWebResponse)webRequest.GetResponse();
-            }
-            catch (WebException e)
-            {
-                httpWebResponse = (HttpWebResponse)e.Response;
-
-                if (httpWebResponse == null)
-                {
-                    // Workaround for mono not closing connections properly in certain situations.
-                    AbortWebRequest(webRequest);
-
-                    // The default messages for WebException on mono are pretty horrible.
-                    if (e.Status == WebExceptionStatus.NameResolutionFailure)
-                    {
-                        throw new WebException($"DNS Name Resolution Failure: '{webRequest.RequestUri.Host}'", e.Status);
-                    }
-                    else if (e.ToString().Contains("TLS Support not"))
-                    {
-                        throw new TlsFailureException(webRequest, e);
-                    }
-                    else if (e.ToString().Contains("The authentication or decryption has failed."))
-                    {
-                        throw new TlsFailureException(webRequest, e);
-                    }
-                    else if (OsInfo.IsNotWindows)
-                    {
-                        throw new WebException($"{e.Message}: '{webRequest.RequestUri}'", e, e.Status, e.Response);
+                cts.CancelAfter(request.RequestTimeout);
             }
             else
             {
+                // The default for System.Net.Http.HttpClient
+                cts.CancelAfter(TimeSpan.FromSeconds(100));
+            }
+
+            if (request.Credentials != null)
+            {
+                if (request.Credentials is BasicNetworkCredential bc)
+                {
+                    // Manually set header to avoid initial challenge response
+                    var authInfo = bc.UserName + ":" + bc.Password;
+                    authInfo = Convert.ToBase64String(Encoding.GetEncoding("ISO-8859-1").GetBytes(authInfo));
+                    requestMessage.Headers.Add("Authorization", "Basic " + authInfo);
+                }
+                else if (request.Credentials is NetworkCredential nc)
+                {
+                    var creds = GetCredentialCache();
+                    foreach (var authtype in new[] { "Basic", "Digest" })
+                    {
+                        creds.Remove((Uri)request.Url, authtype);
+                        creds.Add((Uri)request.Url, authtype, nc);
+                    }
+                }
+            }
+
+            if (request.ContentData != null)
+            {
+                requestMessage.Content = new ByteArrayContent(request.ContentData);
+            }
+
+            if (request.Headers != null)
+            {
+                AddRequestHeaders(requestMessage, request.Headers);
+            }
+
+            var httpClient = GetClient(request.Url);
+
+            HttpResponseMessage responseMessage;
+
+            try
+            {
+                responseMessage = httpClient.Send(requestMessage, cts.Token);
+            }
+            catch (HttpRequestException e)
+            {
+                _logger.Error(e, "HttpClient error");
                 throw;
             }
-                }
-            }
 
             byte[] data = null;
 
-            using (var responseStream = httpWebResponse.GetResponseStream())
+            using (var responseStream = responseMessage.Content.ReadAsStream())
             {
                 if (responseStream != null && responseStream != Stream.Null)
                 {
                     try
+                    {
+                        if (request.ResponseStream != null && responseMessage.StatusCode == HttpStatusCode.OK)
+                        {
+                            // A target ResponseStream was specified, write to that instead.
+                            // But only on the OK status code, since we don't want to write failures and redirects.
+                            responseStream.CopyTo(request.ResponseStream);
+                        }
+                        else
                         {
                             data = responseStream.ToBytes();
                         }
+                    }
                     catch (Exception ex)
                     {
-                        throw new WebException("Failed to read complete http response", ex, WebExceptionStatus.ReceiveFailure, httpWebResponse);
+                        throw new WebException("Failed to read complete http response", ex, WebExceptionStatus.ReceiveFailure, null);
                     }
                 }
             }
 
-            return new HttpResponse(request, new HttpHeader(httpWebResponse.Headers), data, httpWebResponse.StatusCode);
+            var headers = responseMessage.Headers.ToNameValueCollection();
+
+            headers.Add(responseMessage.Content.Headers.ToNameValueCollection());
+
+            return new HttpResponse(request, new HttpHeader(responseMessage.Headers), data, responseMessage.StatusCode);
         }
 
-        protected virtual void AddProxy(HttpWebRequest webRequest, HttpRequest request)
+        protected virtual System.Net.Http.HttpClient GetClient(HttpUri uri)
         {
-            var proxySettings = _proxySettingsProvider.GetProxySettings(request);
+            var proxySettings = _proxySettingsProvider.GetProxySettings(uri);
+
+            var key = proxySettings?.Key ?? NO_PROXY_KEY;
+
+            return _httpClientCache.Get(key, () => CreateHttpClient(proxySettings));
+        }
+
+        protected virtual System.Net.Http.HttpClient CreateHttpClient(HttpProxySettings proxySettings)
+        {
+            var handler = new SocketsHttpHandler()
+            {
+                AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Brotli,
+                UseCookies = false, // sic - we don't want to use a shared cookie container
+                AllowAutoRedirect = false,
+                Credentials = GetCredentialCache(),
+                PreAuthenticate = true,
+                MaxConnectionsPerServer = 12,
+                ConnectCallback = onConnect,
+                SslOptions = new SslClientAuthenticationOptions
+                {
+                    RemoteCertificateValidationCallback = _certificateValidationService.ShouldByPassValidationError
+                }
+            };
+
             if (proxySettings != null)
             {
-                webRequest.Proxy = _createManagedWebProxy.GetWebProxy(proxySettings);
-            }
+                handler.Proxy = _createManagedWebProxy.GetWebProxy(proxySettings);
             }
 
-        protected virtual void AddRequestHeaders(HttpWebRequest webRequest, HttpHeader headers)
+            var client = new System.Net.Http.HttpClient(handler)
+            {
+                Timeout = Timeout.InfiniteTimeSpan
+            };
+
+            return client;
+        }
+
+        protected virtual void AddRequestHeaders(HttpRequestMessage webRequest, HttpHeader headers)
         {
             foreach (var header in headers)
             {
                 switch (header.Key)
                 {
                     case "Accept":
-                        webRequest.Accept = header.Value;
+                        webRequest.Headers.Accept.ParseAdd(header.Value);
                         break;
                     case "Connection":
-                        webRequest.Connection = header.Value;
+                        webRequest.Headers.Connection.Clear();
+                        webRequest.Headers.Connection.Add(header.Value);
                         break;
                     case "Content-Length":
-                        webRequest.ContentLength = Convert.ToInt64(header.Value);
+                        AddContentHeader(webRequest, "Content-Length", header.Value);
                         break;
                     case "Content-Type":
-                        webRequest.ContentType = header.Value;
+                        AddContentHeader(webRequest, "Content-Type", header.Value);
                         break;
                     case "Date":
-                        webRequest.Date = HttpHeader.ParseDateTime(header.Value);
+                        webRequest.Headers.Remove("Date");
+                        webRequest.Headers.Date = HttpHeader.ParseDateTime(header.Value);
                         break;
                     case "Expect":
-                        webRequest.Expect = header.Value;
+                        webRequest.Headers.Expect.ParseAdd(header.Value);
                         break;
                     case "Host":
-                        webRequest.Host = header.Value;
+                        webRequest.Headers.Host = header.Value;
                         break;
                     case "If-Modified-Since":
-                        webRequest.IfModifiedSince = HttpHeader.ParseDateTime(header.Value);
+                        webRequest.Headers.IfModifiedSince = HttpHeader.ParseDateTime(header.Value);
                         break;
                     case "Range":
                         throw new NotImplementedException();
                     case "Referer":
-                        webRequest.Referer = header.Value;
+                        webRequest.Headers.Add("Referer", header.Value);
                         break;
                     case "Transfer-Encoding":
-                        webRequest.TransferEncoding = header.Value;
+                        webRequest.Headers.TransferEncoding.ParseAdd(header.Value);
                         break;
                     case "User-Agent":
-                        throw new NotSupportedException("User-Agent other than Sonarr not allowed.");
+                        webRequest.Headers.UserAgent.ParseAdd(header.Value);
+                        break;
                     case "Proxy-Connection":
                         throw new NotImplementedException();
                     default:
@@ -182,35 +238,82 @@ namespace NzbDrone.Common.Http.Dispatchers
             }
         }
 
-        // Workaround for mono not closing connections properly on timeouts
-        private void AbortWebRequest(HttpWebRequest webRequest)
+        private void AddContentHeader(HttpRequestMessage request, string header, string value)
         {
-            // First affected version was mono 5.16
-            if (OsInfo.IsNotWindows && _platformInfo.Version >= new Version(5, 16))
+            var headers = request.Content?.Headers;
+            if (headers == null)
+            {
+                return;
+            }
+
+            headers.Remove(header);
+            headers.Add(header, value);
+        }
+
+        private CredentialCache GetCredentialCache()
+        {
+            return _credentialCache.Get("credentialCache", () => new CredentialCache());
+        }
+
+        private static async ValueTask<Stream> onConnect(SocketsHttpConnectionContext context, CancellationToken cancellationToken)
+        {
+            // Until .NET supports an implementation of Happy Eyeballs (https://tools.ietf.org/html/rfc8305#section-2), let's make IPv4 fallback work in a simple way.
+            // This issue is being tracked at https://github.com/dotnet/runtime/issues/26177 and expected to be fixed in .NET 6.
+            if (useIPv6)
             {
                 try
                 {
-                    var currentOperationInfo = webRequest.GetType().GetField("currentOperation", BindingFlags.NonPublic | BindingFlags.Instance);
-                    var currentOperation = currentOperationInfo.GetValue(webRequest);
+                    var localToken = cancellationToken;
 
-                    if (currentOperation != null)
+                    if (!hasResolvedIPv6Availability)
                     {
-                        var responseStreamInfo = currentOperation.GetType().GetField("responseStream", BindingFlags.NonPublic | BindingFlags.Instance);
-                        var responseStream = responseStreamInfo.GetValue(currentOperation) as Stream;
+                        // to make things move fast, use a very low timeout for the initial ipv6 attempt.
+                        var quickFailCts = new CancellationTokenSource(connection_establish_timeout);
+                        var linkedTokenSource = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, quickFailCts.Token);
 
-                        // Note that responseStream will likely be null once mono fixes it.
-                        responseStream?.Dispose();
+                        localToken = linkedTokenSource.Token;
                     }
+
+                    return await attemptConnection(AddressFamily.InterNetworkV6, context, localToken);
                 }
-                catch (Exception ex)
+                catch
                 {
-                    // This can fail randomly on future mono versions that have been changed/fixed. Log to sentry and ignore.
-                    _logger.Trace()
-                           .Exception(ex)
-                           .Message("Unable to dispose responseStream on mono {0}", _platformInfo.Version)
-                           .WriteSentryWarn("MonoCloseWaitPatchFailed", ex.Message)
-                           .Write();
+                    // very naively fallback to ipv4 permanently for this execution based on the response of the first connection attempt.
+                    // note that this may cause users to eventually get switched to ipv4 (on a random failure when they are switching networks, for instance)
+                    // but in the interest of keeping this implementation simple, this is acceptable.
+                    useIPv6 = false;
                 }
+                finally
+                {
+                    hasResolvedIPv6Availability = true;
+                }
+            }
+
+            // fallback to IPv4.
+            return await attemptConnection(AddressFamily.InterNetwork, context, cancellationToken);
+        }
+
+        private static async ValueTask<Stream> attemptConnection(AddressFamily addressFamily, SocketsHttpConnectionContext context, CancellationToken cancellationToken)
+        {
+            // The following socket constructor will create a dual-mode socket on systems where IPV6 is available.
+            var socket = new Socket(addressFamily, SocketType.Stream, ProtocolType.Tcp)
+            {
+                // Turn off Nagle's algorithm since it degrades performance in most HttpClient scenarios.
+                NoDelay = true
+            };
+
+            try
+            {
+                await socket.ConnectAsync(context.DnsEndPoint, cancellationToken).ConfigureAwait(false);
+
+                // The stream should take the ownership of the underlying socket,
+                // closing it when it's disposed.
+                return new NetworkStream(socket, ownsSocket: true);
+            }
+            catch
+            {
+                socket.Dispose();
+                throw;
             }
         }
     }

src/NzbDrone.Common/Http/GZipWebClient.cs

@@ -1,15 +0,0 @@
-using System;
-using System.Net;
-
-namespace NzbDrone.Common.Http
-{
-    public class GZipWebClient : WebClient
-    {
-        protected override WebRequest GetWebRequest(Uri address)
-        {
-            var request = (HttpWebRequest)base.GetWebRequest(address);
-            request.AutomaticDecompression = DecompressionMethods.GZip;
-            return request;
-        }
-    }
-}

src/NzbDrone.Common/Http/HttpClient.cs

@@ -1,9 +1,10 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.EnvironmentInfo;
@@ -123,8 +124,6 @@ namespace NzbDrone.Common.Http
 
             var stopWatch = Stopwatch.StartNew();
 
-            PrepareRequestCookies(request, cookieContainer);
-
             var response = _httpDispatcher.GetResponse(request, cookieContainer);
 
             HandleResponseCookies(response, cookieContainer);
@@ -191,45 +190,44 @@ namespace NzbDrone.Common.Http
             }
         }
 
-        private void PrepareRequestCookies(HttpRequest request, CookieContainer cookieContainer)
+        private void HandleResponseCookies(HttpResponse response, CookieContainer container)
         {
-            // Don't collect persistnet cookies for intermediate/redirected urls.
-            /*lock (_cookieContainerCache)
+            foreach (Cookie cookie in container.GetAllCookies())
             {
-                var presistentContainer = _cookieContainerCache.Get("container", () => new CookieContainer());
-                var persistentCookies = presistentContainer.GetCookies((Uri)request.Url);
-                var existingCookies = cookieContainer.GetCookies((Uri)request.Url);
-
-                cookieContainer.Add(persistentCookies);
-                cookieContainer.Add(existingCookies);
-            }*/
+                cookie.Expired = true;
             }
 
-        private void HandleResponseCookies(HttpResponse response, CookieContainer cookieContainer)
-        {
             var cookieHeaders = response.GetCookieHeaders();
+
             if (cookieHeaders.Empty())
             {
                 return;
             }
 
+            AddCookiesToContainer(response.Request.Url, cookieHeaders, container);
+
             if (response.Request.StoreResponseCookie)
             {
                 lock (_cookieContainerCache)
                 {
                     var persistentCookieContainer = _cookieContainerCache.Get("container", () => new CookieContainer());
 
+                    AddCookiesToContainer(response.Request.Url, cookieHeaders, persistentCookieContainer);
+                }
+            }
+        }
+
+        private void AddCookiesToContainer(HttpUri url, string[] cookieHeaders, CookieContainer container)
+        {
             foreach (var cookieHeader in cookieHeaders)
             {
                 try
                 {
-                            persistentCookieContainer.SetCookies((Uri)response.Request.Url, cookieHeader);
+                    container.SetCookies((Uri)url, cookieHeader);
                 }
                 catch (Exception ex)
                 {
-                            _logger.Debug(ex, "Invalid cookie in {0}", response.Request.Url);
-                        }
-                    }
+                    _logger.Debug(ex, "Invalid cookie in {0}", url);
                 }
             }
         }
@@ -252,6 +250,7 @@ namespace NzbDrone.Common.Http
                 using (var fileStream = new FileStream(fileNamePart, FileMode.Create, FileAccess.ReadWrite))
                 {
                     var request = new HttpRequest(url);
+                    request.AllowAutoRedirect = true;
                     request.ResponseStream = fileStream;
                     var response = Get(request);
 
@@ -281,7 +280,7 @@ namespace NzbDrone.Common.Http
 
         public HttpResponse Get(HttpRequest request)
         {
-            request.Method = HttpMethod.GET;
+            request.Method = HttpMethod.Get;
             return Execute(request);
         }
 
@@ -295,13 +294,13 @@ namespace NzbDrone.Common.Http
 
         public HttpResponse Head(HttpRequest request)
         {
-            request.Method = HttpMethod.HEAD;
+            request.Method = HttpMethod.Head;
             return Execute(request);
         }
 
         public HttpResponse Post(HttpRequest request)
         {
-            request.Method = HttpMethod.POST;
+            request.Method = HttpMethod.Post;
             return Execute(request);
         }
 

src/NzbDrone.Common/Http/HttpHeader.cs

@@ -1,14 +1,29 @@
-using System;
+using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.Globalization;
 using System.Linq;
+using System.Net.Http.Headers;
 using System.Text;
 using NzbDrone.Common.Extensions;
 
 namespace NzbDrone.Common.Http
 {
+    public static class WebHeaderCollectionExtensions
+    {
+        public static NameValueCollection ToNameValueCollection(this HttpHeaders headers)
+        {
+            var result = new NameValueCollection();
+            foreach (var header in headers)
+            {
+                result.Add(header.Key, header.Value.ConcatToString(";"));
+            }
+
+            return result;
+        }
+    }
+
     public class HttpHeader : NameValueCollection, IEnumerable<KeyValuePair<string, string>>, IEnumerable
     {
         public HttpHeader(NameValueCollection headers)
@@ -16,6 +31,11 @@ namespace NzbDrone.Common.Http
         {
         }
 
+        public HttpHeader(HttpHeaders headers)
+            : base(headers.ToNameValueCollection())
+        {
+        }
+
         public HttpHeader()
         {
         }

src/NzbDrone.Common/Http/HttpMethod.cs

@@ -1,14 +0,0 @@
-namespace NzbDrone.Common.Http
-{
-    public enum HttpMethod
-    {
-        GET,
-        POST,
-        PUT,
-        DELETE,
-        HEAD,
-        OPTIONS,
-        PATCH,
-        MERGE
-    }
-}

src/NzbDrone.Common/Http/HttpRequest.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Net;
+using System.Net.Http;
 using System.Text;
 using NzbDrone.Common.EnvironmentInfo;
 using NzbDrone.Common.Extensions;
@@ -12,6 +13,7 @@ namespace NzbDrone.Common.Http
     {
         public HttpRequest(string url, HttpAccept httpAccept = null)
         {
+            Method = HttpMethod.Get;
             Url = new HttpUri(url);
             Headers = new HttpHeader();
             AllowAutoRedirect = true;
@@ -35,6 +37,7 @@ namespace NzbDrone.Common.Http
         public HttpHeader Headers { get; set; }
         public byte[] ContentData { get; set; }
         public string ContentSummary { get; set; }
+        public ICredentials Credentials { get; set; }
         public bool SuppressHttpError { get; set; }
         public IEnumerable<HttpStatusCode> SuppressHttpErrorStatusCodes { get; set; }
         public bool UseSimplifiedUserAgent { get; set; }
@@ -85,12 +88,5 @@ namespace NzbDrone.Common.Http
             var encoding = HttpHeader.GetEncodingFromContentType(Headers.ContentType);
             ContentData = encoding.GetBytes(data);
         }
-
-        public void AddBasicAuthentication(string username, string password)
-        {
-            var authInfo = Convert.ToBase64String(Encoding.GetEncoding("ISO-8859-1").GetBytes($"{username}:{password}"));
-
-            Headers.Set("Authorization", "Basic " + authInfo);
-        }
     }
 }

src/NzbDrone.Common/Http/HttpRequestBuilder.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using System.Text;
 using NzbDrone.Common.Extensions;
 
@@ -25,17 +26,16 @@ namespace NzbDrone.Common.Http
         public bool ConnectionKeepAlive { get; set; }
         public TimeSpan RateLimit { get; set; }
         public bool LogResponseContent { get; set; }
-        public NetworkCredential NetworkCredential { get; set; }
+        public ICredentials NetworkCredential { get; set; }
         public Dictionary<string, string> Cookies { get; private set; }
         public List<HttpFormData> FormData { get; private set; }
-
         public Action<HttpRequest> PostProcess { get; set; }
 
         public HttpRequestBuilder(string baseUrl)
         {
             BaseUrl = new HttpUri(baseUrl);
             ResourceUrl = string.Empty;
-            Method = HttpMethod.GET;
+            Method = HttpMethod.Get;
             QueryParams = new List<KeyValuePair<string, string>>();
             SuffixQueryParams = new List<KeyValuePair<string, string>>();
             Segments = new Dictionary<string, string>();
@@ -108,13 +108,7 @@ namespace NzbDrone.Common.Http
             request.ConnectionKeepAlive = ConnectionKeepAlive;
             request.RateLimit = RateLimit;
             request.LogResponseContent = LogResponseContent;
-
-            if (NetworkCredential != null)
-            {
-                var authInfo = NetworkCredential.UserName + ":" + NetworkCredential.Password;
-                authInfo = Convert.ToBase64String(Encoding.GetEncoding("ISO-8859-1").GetBytes(authInfo));
-                request.Headers.Set("Authorization", "Basic " + authInfo);
-            }
+            request.Credentials = NetworkCredential;
 
             foreach (var header in Headers)
             {
@@ -272,7 +266,7 @@ namespace NzbDrone.Common.Http
 
         public virtual HttpRequestBuilder Post()
         {
-            Method = HttpMethod.POST;
+            Method = HttpMethod.Post;
 
             return this;
         }
@@ -363,7 +357,7 @@ namespace NzbDrone.Common.Http
 
         public virtual HttpRequestBuilder AddFormParameter(string key, object value)
         {
-            if (Method != HttpMethod.POST)
+            if (Method != HttpMethod.Post)
             {
                 throw new NotSupportedException("HttpRequest Method must be POST to add FormParameter.");
             }
@@ -379,7 +373,7 @@ namespace NzbDrone.Common.Http
 
         public virtual HttpRequestBuilder AddFormUpload(string name, string fileName, byte[] data, string contentType = "application/octet-stream")
         {
-            if (Method != HttpMethod.POST)
+            if (Method != HttpMethod.Post)
             {
                 throw new NotSupportedException("HttpRequest Method must be POST to add FormUpload.");
             }

src/NzbDrone.Common/Http/JsonRpcRequestBuilder.cs

@@ -1,6 +1,7 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using Newtonsoft.Json;
 using NzbDrone.Common.Serializer;
 
@@ -17,14 +18,14 @@ namespace NzbDrone.Common.Http
         public JsonRpcRequestBuilder(string baseUrl)
             : base(baseUrl)
         {
-            Method = HttpMethod.POST;
+            Method = HttpMethod.Post;
             JsonParameters = new List<object>();
         }
 
         public JsonRpcRequestBuilder(string baseUrl, string method, IEnumerable<object> parameters)
             : base(baseUrl)
         {
-            Method = HttpMethod.POST;
+            Method = HttpMethod.Post;
             JsonMethod = method;
             JsonParameters = parameters.ToList();
         }

src/NzbDrone.Common/Http/NzbDroneWebClient.cs

@@ -1,20 +0,0 @@
-using System;
-using System.Net;
-
-namespace NzbDrone.Common.Http
-{
-    public class NzbDroneWebClient : WebClient
-    {
-        protected override WebRequest GetWebRequest(Uri address)
-        {
-            var request = base.GetWebRequest(address);
-            if (request is HttpWebRequest)
-            {
-                ((HttpWebRequest)request).KeepAlive = false;
-                ((HttpWebRequest)request).ServicePoint.Expect100Continue = false;
-            }
-
-            return request;
-        }
-    }
-}

src/NzbDrone.Common/Http/Proxy/IHttpProxySettingsProvider.cs

@@ -2,7 +2,7 @@ namespace NzbDrone.Common.Http.Proxy
 {
     public interface IHttpProxySettingsProvider
     {
-        HttpProxySettings GetProxySettings(HttpRequest request);
+        HttpProxySettings GetProxySettings(HttpUri uri);
         HttpProxySettings GetProxySettings();
     }
 }

src/NzbDrone.Common/Http/XmlRpcRequestBuilder.cs

@@ -0,0 +1,103 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Xml.Linq;
+using NLog;
+using NzbDrone.Common.Instrumentation;
+
+namespace NzbDrone.Common.Http
+{
+    public class XmlRpcRequestBuilder : HttpRequestBuilder
+    {
+        public static string XmlRpcContentType = "text/xml";
+
+        private static readonly Logger Logger = NzbDroneLogger.GetLogger(typeof(XmlRpcRequestBuilder));
+
+        public string XmlMethod { get; private set; }
+        public List<object> XmlParameters { get; private set; }
+
+        public XmlRpcRequestBuilder(string baseUrl)
+            : base(baseUrl)
+        {
+            Method = HttpMethod.Post;
+            XmlParameters = new List<object>();
+        }
+
+        public XmlRpcRequestBuilder(bool useHttps, string host, int port, string urlBase = null)
+            : this(BuildBaseUrl(useHttps, host, port, urlBase))
+        {
+        }
+
+        public override HttpRequestBuilder Clone()
+        {
+            var clone = base.Clone() as XmlRpcRequestBuilder;
+            clone.XmlParameters = new List<object>(XmlParameters);
+            return clone;
+        }
+
+        public XmlRpcRequestBuilder Call(string method, params object[] parameters)
+        {
+            var clone = Clone() as XmlRpcRequestBuilder;
+            clone.XmlMethod = method;
+            clone.XmlParameters = parameters.ToList();
+            return clone;
+        }
+
+        protected override void Apply(HttpRequest request)
+        {
+            base.Apply(request);
+
+            request.Headers.ContentType = XmlRpcContentType;
+
+            var methodCallElements = new List<XElement> { new XElement("methodName", XmlMethod) };
+
+            if (XmlParameters.Any())
+            {
+                var argElements = XmlParameters.Select(x => new XElement("param", ConvertParameter(x))).ToList();
+                var paramsElement = new XElement("params", argElements);
+                methodCallElements.Add(paramsElement);
+            }
+
+            var message = new XDocument(
+                new XDeclaration("1.0", "utf-8", "yes"),
+                new XElement("methodCall", methodCallElements));
+
+            var body = message.ToString();
+
+            Logger.Debug($"Executing remote method: {XmlMethod}");
+
+            Logger.Trace($"methodCall {XmlMethod} body:\n{body}");
+
+            request.SetContent(body);
+        }
+
+        private static XElement ConvertParameter(object value)
+        {
+            XElement data;
+
+            if (value is string s)
+            {
+                data = new XElement("string", s);
+            }
+            else if (value is List<string> l)
+            {
+                data = new XElement("array", new XElement("data", l.Select(x => new XElement("value", new XElement("string", x)))));
+            }
+            else if (value is int i)
+            {
+                data = new XElement("int", i);
+            }
+            else if (value is byte[] bytes)
+            {
+                data = new XElement("base64", Convert.ToBase64String(bytes));
+            }
+            else
+            {
+                throw new InvalidOperationException($"Unhandled argument type {value.GetType().Name}");
+            }
+
+            return new XElement("value", data);
+        }
+    }
+}

src/NzbDrone.Core.Test/Framework/CoreTest.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using NUnit.Framework;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Cloud;
@@ -9,6 +9,7 @@ using NzbDrone.Common.Http.Proxy;
 using NzbDrone.Common.TPL;
 using NzbDrone.Core.Configuration;
 using NzbDrone.Core.Http;
+using NzbDrone.Core.Security;
 using NzbDrone.Test.Common;
 
 namespace NzbDrone.Core.Test.Framework
@@ -23,7 +24,8 @@ namespace NzbDrone.Core.Test.Framework
 
             Mocker.SetConstant<IHttpProxySettingsProvider>(new HttpProxySettingsProvider(Mocker.Resolve<ConfigService>()));
             Mocker.SetConstant<ICreateManagedWebProxy>(new ManagedWebProxyFactory(Mocker.Resolve<CacheManager>()));
-            Mocker.SetConstant<IHttpDispatcher>(new ManagedHttpDispatcher(Mocker.Resolve<IHttpProxySettingsProvider>(), Mocker.Resolve<ICreateManagedWebProxy>(), Mocker.Resolve<UserAgentBuilder>(), Mocker.Resolve<IPlatformInfo>(), TestLogger));
+            Mocker.SetConstant<ICertificateValidationService>(new X509CertificateValidationService(Mocker.Resolve<ConfigService>(), TestLogger));
+            Mocker.SetConstant<IHttpDispatcher>(new ManagedHttpDispatcher(Mocker.Resolve<IHttpProxySettingsProvider>(), Mocker.Resolve<ICreateManagedWebProxy>(), Mocker.Resolve<ICertificateValidationService>(), Mocker.Resolve<UserAgentBuilder>(), Mocker.Resolve<CacheManager>(), TestLogger));
             Mocker.SetConstant<IHttpClient>(new HttpClient(new IHttpRequestInterceptor[0], Mocker.Resolve<CacheManager>(), Mocker.Resolve<RateLimitService>(), Mocker.Resolve<IHttpDispatcher>(), Mocker.Resolve<UserAgentBuilder>(), TestLogger));
             Mocker.SetConstant<ISonarrCloudRequestBuilder>(new SonarrCloudRequestBuilder());
         }

src/NzbDrone.Core.Test/IndexerTests/BroadcastheNetTests/BroadcastheNetFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -31,7 +32,7 @@ namespace NzbDrone.Core.Test.IndexerTests.BroadcastheNetTests
             var recentFeed = ReadAllText(@"Files/Indexers/BroadcastheNet/RecentFeed.json");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.POST)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Post)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -144,7 +145,7 @@ namespace NzbDrone.Core.Test.IndexerTests.BroadcastheNetTests
             recentFeed = recentFeed.Replace("http:", "https:");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.POST)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Post)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/FanzubTests/FanzubFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -29,7 +30,7 @@ namespace NzbDrone.Core.Test.IndexerTests.FanzubTests
             var recentFeed = ReadAllText(@"Files/Indexers/Fanzub/fanzub.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/FileListTests/FileListFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -30,7 +31,7 @@ namespace NzbDrone.Core.Test.IndexerTests.FileListTests
             var recentFeed = ReadAllText(@"Files/Indexers/FileList/RecentFeed.json");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/HDBitsTests/HDBitsFixture.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Linq;
+using System.Net.Http;
 using System.Text;
 using FluentAssertions;
 using Moq;
@@ -34,7 +35,7 @@ namespace NzbDrone.Core.Test.IndexerTests.HDBitsTests
             var responseJson = ReadAllText(fileName);
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.POST)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Post)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), responseJson));
 
             var torrents = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/IPTorrentsTests/IPTorrentsFixture.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -88,7 +89,7 @@ namespace NzbDrone.Core.Test.IndexerTests.IPTorrentsTests
             var recentFeed = ReadAllText(@"Files/Indexers/IPTorrents/IPTorrents.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/NewznabTests/NewznabFixture.cs

@@ -1,6 +1,7 @@
-using System;
+using System;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -44,7 +45,7 @@ namespace NzbDrone.Core.Test.IndexerTests.NewznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Newznab/newznab_nzb_su.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -70,7 +71,7 @@ namespace NzbDrone.Core.Test.IndexerTests.NewznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torznab/torznab_animetosho.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/NyaaTests/NyaaFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -32,7 +33,7 @@ namespace NzbDrone.Core.Test.IndexerTests.NyaaTests
             var recentFeed = ReadAllText(@"Files/Indexers/Nyaa/Nyaa.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -62,7 +63,7 @@ namespace NzbDrone.Core.Test.IndexerTests.NyaaTests
             var recentFeed = ReadAllText(@"Files/Indexers/Nyaa/Nyaa2021.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/OmgwtfnzbsTests/OmgwtfnzbsFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -33,7 +34,7 @@ namespace NzbDrone.Core.Test.IndexerTests.OmgwtfnzbsTests
             var recentFeed = ReadAllText(@"Files/Indexers/Omgwtfnzbs/Omgwtfnzbs.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/RarbgTests/RarbgFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -35,7 +36,7 @@ namespace NzbDrone.Core.Test.IndexerTests.RarbgTests
             var recentFeed = ReadAllText(@"Files/Indexers/Rarbg/RecentFeed_v2.json");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -64,7 +65,7 @@ namespace NzbDrone.Core.Test.IndexerTests.RarbgTests
         public void should_parse_error_20_as_empty_results()
         {
             Mocker.GetMock<IHttpClient>()
-                   .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                   .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                    .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), "{ error_code: 20, error: \"some message\" }"));
 
             var releases = Subject.FetchRecent();
@@ -76,7 +77,7 @@ namespace NzbDrone.Core.Test.IndexerTests.RarbgTests
         public void should_warn_on_unknown_error()
         {
             Mocker.GetMock<IHttpClient>()
-                   .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                   .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                    .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), "{ error_code: 25, error: \"some message\" }"));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/SeasonSearchFixture.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
+using System.Net.Http;
 using FizzWare.NBuilder;
 using Moq;
 using NUnit.Framework;
@@ -22,7 +23,7 @@ namespace NzbDrone.Core.Test.IndexerTests
             _series = Builder<Series>.CreateNew().Build();
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), "<xml></xml>"));
         }
 
@@ -40,7 +41,7 @@ namespace NzbDrone.Core.Test.IndexerTests
             var requests = Builder<IndexerRequest>.CreateListOfSize(paging ? 100 : 1)
                 .All()
                 .WithFactory(() => new IndexerRequest("http://my.feed.local/", HttpAccept.Rss))
-                .With(v => v.HttpRequest.Method = HttpMethod.GET)
+                .With(v => v.HttpRequest.Method = HttpMethod.Get)
                 .Build();
 
             var pageable = new IndexerPageableRequestChain();

src/NzbDrone.Core.Test/IndexerTests/TorrentleechTests/TorrentleechFixture.cs

@@ -1,5 +1,6 @@
-using System;
+using System;
 using System.Linq;
+using System.Net.Http;
 using FluentAssertions;
 using Moq;
 using NUnit.Framework;
@@ -30,7 +31,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorrentleechTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torrentleech/Torrentleech.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();

src/NzbDrone.Core.Test/IndexerTests/TorznabTests/TorznabFixture.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using System.Net.Http;
 using FizzWare.NBuilder;
@@ -49,7 +49,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torznab/torznab_hdaccess_net.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -80,7 +80,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torznab/torznab_tpb.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -110,7 +110,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torznab/torznab_animetosho.xml");
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var releases = Subject.FetchRecent();
@@ -164,7 +164,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorznabTests
             (Subject.Definition.Settings as TorznabSettings).BaseUrl = baseUrl;
 
             Mocker.GetMock<IHttpClient>()
-                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                 .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             var result = new NzbDroneValidationResult(Subject.Test());
@@ -179,7 +179,7 @@ namespace NzbDrone.Core.Test.IndexerTests.TorznabTests
             var recentFeed = ReadAllText(@"Files/Indexers/Torznab/torznab_tpb.xml");
 
             Mocker.GetMock<IHttpClient>()
-                  .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.GET)))
+                  .Setup(o => o.Execute(It.Is<HttpRequest>(v => v.Method == HttpMethod.Get)))
                   .Returns<HttpRequest>(r => new HttpResponse(r, new HttpHeader(), recentFeed));
 
             (Subject.Definition.Settings as TorznabSettings).ApiPath = apiPath;

src/NzbDrone.Core/Download/Clients/Aria2/Aria2.cs

@@ -2,7 +2,6 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
-using CookComputing.XmlRpc;
 using FluentValidation.Results;
 using NLog;
 using NzbDrone.Common.Disk;
@@ -90,12 +89,7 @@ namespace NzbDrone.Core.Download.Clients.Aria2
                 var downloadSpeed = long.Parse(torrent.DownloadSpeed);
 
                 var status = DownloadItemStatus.Failed;
-                var title = "";
-
-                if (torrent.Bittorrent?.ContainsKey("info") == true && ((XmlRpcStruct)torrent.Bittorrent["info"]).ContainsKey("name"))
-                {
-                    title = ((XmlRpcStruct)torrent.Bittorrent["info"])["name"].ToString();
-                }
+                var title = torrent.Bittorrent?.Name ?? "";
 
                 switch (torrent.Status)
                 {

src/NzbDrone.Core/Download/Clients/Aria2/Aria2Containers.cs

@@ -1,111 +1,161 @@
-using CookComputing.XmlRpc;
+using System.Collections.Generic;
+using System.Linq;
+using System.Xml.Linq;
+using System.Xml.XPath;
+using NzbDrone.Core.Download.Extensions;
 
 namespace NzbDrone.Core.Download.Clients.Aria2
 {
-    public class Aria2Version
+    public class Aria2Fault
     {
-        [XmlRpcMember("version")]
-        public string Version;
-
-        [XmlRpcMember("enabledFeatures")]
-        public string[] EnabledFeatures;
+        public Aria2Fault(XElement element)
+        {
+            foreach (var e in element.XPathSelectElements("./value/struct/member"))
+            {
+                var name = e.ElementAsString("name");
+                if (name == "faultCode")
+                {
+                    FaultCode = e.Element("value").ElementAsInt("int");
+                }
+                else if (name == "faultString")
+                {
+                    FaultString = e.Element("value").GetStringValue();
+                }
+            }
         }
 
-    public class Aria2Uri
-    {
-        [XmlRpcMember("status")]
-        public string Status;
+        public int FaultCode { get; set; }
+        public string FaultString { get; set; }
+    }
 
-        [XmlRpcMember("uri")]
-        public string Uri;
+    public class Aria2Version
+    {
+        public Aria2Version(XElement element)
+        {
+            foreach (var e in element.XPathSelectElements("./struct/member"))
+            {
+                if (e.ElementAsString("name") == "version")
+                {
+                    Version = e.Element("value").GetStringValue();
+                }
+            }
+        }
+
+        public string Version { get; set; }
     }
 
     public class Aria2File
     {
-        [XmlRpcMember("index")]
-        public string Index;
+        public Aria2File(XElement element)
+        {
+            foreach (var e in element.XPathSelectElements("./struct/member"))
+            {
+                var name = e.ElementAsString("name");
 
-        [XmlRpcMember("length")]
-        public string Length;
+                if (name == "path")
+                {
+                    Path = e.Element("value").GetStringValue();
+                }
+            }
+        }
 
-        [XmlRpcMember("completedLength")]
-        public string CompletedLength;
+        public string Path { get; set; }
+    }
 
-        [XmlRpcMember("path")]
-        public string Path;
+    public class Aria2Dict
+    {
+        public Aria2Dict(XElement element)
+        {
+            Dict = new Dictionary<string, string>();
 
-        [XmlRpcMember("selected")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string Selected;
+            foreach (var e in element.XPathSelectElements("./struct/member"))
+            {
+                Dict.Add(e.ElementAsString("name"), e.Element("value").GetStringValue());
+            }
+        }
 
-        [XmlRpcMember("uris")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public Aria2Uri[] Uris;
+        public Dictionary<string, string> Dict { get; set; }
+    }
+
+    public class Aria2Bittorrent
+    {
+        public Aria2Bittorrent(XElement element)
+        {
+            foreach (var e in element.Descendants("member"))
+            {
+                if (e.ElementAsString("name") == "name")
+                {
+                    Name = e.Element("value").GetStringValue();
+                }
+            }
+        }
+
+        public string Name;
     }
 
     public class Aria2Status
     {
-        [XmlRpcMember("bittorrent")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public XmlRpcStruct Bittorrent;
+        public Aria2Status(XElement element)
+        {
+            foreach (var e in element.XPathSelectElements("./struct/member"))
+            {
+                var name = e.ElementAsString("name");
 
-        [XmlRpcMember("bitfield")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string Bitfield;
+                if (name == "bittorrent")
+                {
+                    Bittorrent = new Aria2Bittorrent(e.Element("value"));
+                }
+                else if (name == "infoHash")
+                {
+                    InfoHash = e.Element("value").GetStringValue();
+                }
+                else if (name == "completedLength")
+                {
+                    CompletedLength = e.Element("value").GetStringValue();
+                }
+                else if (name == "downloadSpeed")
+                {
+                    DownloadSpeed = e.Element("value").GetStringValue();
+                }
+                else if (name == "files")
+                {
+                    Files = e.XPathSelectElement("./value/array/data")
+                        .Elements()
+                        .Select(x => new Aria2File(x))
+                        .ToArray();
+                }
+                else if (name == "gid")
+                {
+                    Gid = e.Element("value").GetStringValue();
+                }
+                else if (name == "status")
+                {
+                    Status = e.Element("value").GetStringValue();
+                }
+                else if (name == "totalLength")
+                {
+                    TotalLength = e.Element("value").GetStringValue();
+                }
+                else if (name == "uploadLength")
+                {
+                    UploadLength = e.Element("value").GetStringValue();
+                }
+                else if (name == "errorMessage")
+                {
+                    ErrorMessage = e.Element("value").GetStringValue();
+                }
+            }
+        }
 
-        [XmlRpcMember("infoHash")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string InfoHash;
-
-        [XmlRpcMember("completedLength")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string CompletedLength;
-
-        [XmlRpcMember("connections")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string Connections;
-
-        [XmlRpcMember("dir")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string Dir;
-
-        [XmlRpcMember("downloadSpeed")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string DownloadSpeed;
-
-        [XmlRpcMember("files")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public Aria2File[] Files;
-
-        [XmlRpcMember("gid")]
-        public string Gid;
-
-        [XmlRpcMember("numPieces")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string NumPieces;
-
-        [XmlRpcMember("pieceLength")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string PieceLength;
-
-        [XmlRpcMember("status")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string Status;
-
-        [XmlRpcMember("totalLength")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string TotalLength;
-
-        [XmlRpcMember("uploadLength")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string UploadLength;
-
-        [XmlRpcMember("uploadSpeed")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string UploadSpeed;
-
-        [XmlRpcMember("errorMessage")]
-        [XmlRpcMissingMapping(MappingAction.Ignore)]
-        public string ErrorMessage;
+        public Aria2Bittorrent Bittorrent { get; set; }
+        public string InfoHash { get; set; }
+        public string CompletedLength { get; set; }
+        public string DownloadSpeed { get; set; }
+        public Aria2File[] Files { get; set; }
+        public string Gid { get; set; }
+        public string Status { get; set; }
+        public string TotalLength { get; set; }
+        public string UploadLength { get; set; }
+        public string ErrorMessage { get; set; }
     }
 }

src/NzbDrone.Core/Download/Clients/Aria2/Aria2Proxy.cs

@@ -1,9 +1,9 @@
-using System;
-using System.Collections;
 using System.Collections.Generic;
-using System.Net;
-using CookComputing.XmlRpc;
-using NLog;
+using System.Linq;
+using System.Xml.Linq;
+using System.Xml.XPath;
+using NzbDrone.Common.Http;
+using NzbDrone.Core.Download.Extensions;
 
 namespace NzbDrone.Core.Download.Clients.Aria2
 {
@@ -19,103 +19,61 @@ namespace NzbDrone.Core.Download.Clients.Aria2
         Aria2Status GetFromGID(Aria2Settings settings, string gid);
     }
 
-    public interface IAria2 : IXmlRpcProxy
-    {
-        [XmlRpcMethod("aria2.getVersion")]
-        Aria2Version GetVersion(string token);
-
-        [XmlRpcMethod("aria2.addUri")]
-        string AddUri(string token, string[] uri);
-
-        [XmlRpcMethod("aria2.addTorrent")]
-        string AddTorrent(string token, byte[] torrent);
-
-        [XmlRpcMethod("aria2.forceRemove")]
-        string Remove(string token, string gid);
-
-        [XmlRpcMethod("aria2.removeDownloadResult")]
-        string RemoveResult(string token, string gid);
-
-        [XmlRpcMethod("aria2.tellStatus")]
-        Aria2Status GetFromGid(string token, string gid);
-
-        [XmlRpcMethod("aria2.getGlobalOption")]
-        XmlRpcStruct GetGlobalOption(string token);
-
-        [XmlRpcMethod("aria2.tellActive")]
-        Aria2Status[] GetActive(string token);
-
-        [XmlRpcMethod("aria2.tellWaiting")]
-        Aria2Status[] GetWaiting(string token, int offset, int num);
-
-        [XmlRpcMethod("aria2.tellStopped")]
-        Aria2Status[] GetStopped(string token, int offset, int num);
-    }
-
     public class Aria2Proxy : IAria2Proxy
     {
-        private readonly Logger _logger;
+        private readonly IHttpClient _httpClient;
 
-        public Aria2Proxy(Logger logger)
+        public Aria2Proxy(IHttpClient httpClient)
         {
-            _logger = logger;
-        }
-
-        private string GetToken(Aria2Settings settings)
-        {
-            return $"token:{settings?.SecretToken}";
-        }
-
-        private string GetURL(Aria2Settings settings)
-        {
-            return $"http{(settings.UseSsl ? "s" : "")}://{settings.Host}:{settings.Port}{settings.RpcPath}";
+            _httpClient = httpClient;
         }
 
         public string GetVersion(Aria2Settings settings)
         {
-            _logger.Trace("> aria2.getVersion");
+            var response = ExecuteRequest(settings, "aria2.getVersion", GetToken(settings));
 
-            var client = BuildClient(settings);
-            var version = ExecuteRequest(() => client.GetVersion(GetToken(settings)));
+            var element = response.XPathSelectElement("./methodResponse/params/param/value");
 
-            _logger.Trace("< aria2.getVersion");
+            var version = new Aria2Version(element);
 
             return version.Version;
         }
 
         public Aria2Status GetFromGID(Aria2Settings settings, string gid)
         {
-            _logger.Trace("> aria2.tellStatus");
+            var response = ExecuteRequest(settings, "aria2.tellStatus", GetToken(settings), gid);
 
-            var client = BuildClient(settings);
-            var found = ExecuteRequest(() => client.GetFromGid(GetToken(settings), gid));
+            var element = response.XPathSelectElement("./methodResponse/params/param/value");
 
-            _logger.Trace("< aria2.tellStatus");
+            return new Aria2Status(element);
+        }
 
-            return found;
+        private List<Aria2Status> GetTorrentsMethod(Aria2Settings settings, string method, params object[] args)
+        {
+            var allArgs = new List<object> { GetToken(settings) };
+            if (args.Any())
+            {
+                allArgs.AddRange(args);
+            }
+
+            var response = ExecuteRequest(settings, method, allArgs.ToArray());
+
+            var element = response.XPathSelectElement("./methodResponse/params/param/value/array/data");
+
+            var torrents = element?.Elements()
+                               .Select(x => new Aria2Status(x))
+                               .ToList()
+                           ?? new List<Aria2Status>();
+            return torrents;
         }
 
         public List<Aria2Status> GetTorrents(Aria2Settings settings)
         {
-            _logger.Trace("> aria2.tellActive");
+            var active = GetTorrentsMethod(settings, "aria2.tellActive");
 
-            var client = BuildClient(settings);
+            var waiting = GetTorrentsMethod(settings, "aria2.tellWaiting", 0, 10 * 1024);
 
-            var active = ExecuteRequest(() => client.GetActive(GetToken(settings)));
-
-            _logger.Trace("< aria2.tellActive");
-
-            _logger.Trace("> aria2.tellWaiting");
-
-            var waiting = ExecuteRequest(() => client.GetWaiting(GetToken(settings), 0, 10 * 1024));
-
-            _logger.Trace("< aria2.tellWaiting");
-
-            _logger.Trace("> aria2.tellStopped");
-
-            var stopped = ExecuteRequest(() => client.GetStopped(GetToken(settings), 0, 10 * 1024));
-
-            _logger.Trace("< aria2.tellStopped");
+            var stopped = GetTorrentsMethod(settings, "aria2.tellStopped", 0, 10 * 1024);
 
             var items = new List<Aria2Status>();
 
@@ -128,98 +86,79 @@ namespace NzbDrone.Core.Download.Clients.Aria2
 
         public Dictionary<string, string> GetGlobals(Aria2Settings settings)
         {
-            _logger.Trace("> aria2.getGlobalOption");
+            var response = ExecuteRequest(settings, "aria2.getGlobalOption", GetToken(settings));
 
-            var client = BuildClient(settings);
-            var options = ExecuteRequest(() => client.GetGlobalOption(GetToken(settings)));
+            var element = response.XPathSelectElement("./methodResponse/params/param/value");
 
-            _logger.Trace("< aria2.getGlobalOption");
+            var result = new Aria2Dict(element);
 
-            var ret = new Dictionary<string, string>();
-
-            foreach (DictionaryEntry option in options)
-            {
-                ret.Add(option.Key.ToString(), option.Value?.ToString());
-            }
-
-            return ret;
+            return result.Dict;
         }
 
         public string AddMagnet(Aria2Settings settings, string magnet)
         {
-            _logger.Trace("> aria2.addUri");
+            var response = ExecuteRequest(settings, "aria2.addUri", GetToken(settings), new List<string> { magnet });
 
-            var client = BuildClient(settings);
-            var gid = ExecuteRequest(() => client.AddUri(GetToken(settings), new[] { magnet }));
-
-            _logger.Trace("< aria2.addUri");
+            var gid = response.GetStringResponse();
 
             return gid;
         }
 
         public string AddTorrent(Aria2Settings settings, byte[] torrent)
         {
-            _logger.Trace("> aria2.addTorrent");
+            var response = ExecuteRequest(settings, "aria2.addTorrent", GetToken(settings), torrent);
 
-            var client = BuildClient(settings);
-            var gid = ExecuteRequest(() => client.AddTorrent(GetToken(settings), torrent));
-
-            _logger.Trace("< aria2.addTorrent");
+            var gid = response.GetStringResponse();
 
             return gid;
         }
 
         public bool RemoveTorrent(Aria2Settings settings, string gid)
         {
-            _logger.Trace("> aria2.forceRemove");
+            var response = ExecuteRequest(settings, "aria2.forceRemove", GetToken(settings), gid);
 
-            var client = BuildClient(settings);
-            var gidres = ExecuteRequest(() => client.Remove(GetToken(settings), gid));
-
-            _logger.Trace("< aria2.forceRemove");
+            var gidres = response.GetStringResponse();
 
             return gid == gidres;
         }
 
         public bool RemoveCompletedTorrent(Aria2Settings settings, string gid)
         {
-            _logger.Trace("> aria2.removeDownloadResult");
+            var response = ExecuteRequest(settings, "aria2.removeDownloadResult", GetToken(settings), gid);
 
-            var client = BuildClient(settings);
-            var result = ExecuteRequest(() => client.RemoveResult(GetToken(settings), gid));
-
-            _logger.Trace("< aria2.removeDownloadResult");
+            var result = response.GetStringResponse();
 
             return result == "OK";
         }
 
-        private IAria2 BuildClient(Aria2Settings settings)
+        private string GetToken(Aria2Settings settings)
         {
-            var client = XmlRpcProxyGen.Create<IAria2>();
-            client.Url = GetURL(settings);
-
-            return client;
+            return $"token:{settings?.SecretToken}";
         }
 
-        private T ExecuteRequest<T>(Func<T> task)
+        private XDocument ExecuteRequest(Aria2Settings settings, string methodName, params object[] args)
         {
-            try
+            var requestBuilder = new XmlRpcRequestBuilder(settings.UseSsl, settings.Host, settings.Port, settings.RpcPath)
             {
-                return task();
-            }
-            catch (XmlRpcServerException ex)
+                LogResponseContent = true,
+            };
+
+            var request = requestBuilder.Call(methodName, args).Build();
+
+            var response = _httpClient.Execute(request);
+
+            var doc = XDocument.Parse(response.Content);
+
+            var faultElement = doc.XPathSelectElement("./methodResponse/fault");
+
+            if (faultElement != null)
             {
-                throw new DownloadClientException("Unable to connect to aria2, please check your settings", ex);
-            }
-            catch (WebException ex)
-            {
-                if (ex.Status == WebExceptionStatus.TrustFailure)
-                {
-                    throw new DownloadClientUnavailableException("Unable to connect to aria2, certificate validation failed.", ex);
+                var fault = new Aria2Fault(faultElement);
+
+                throw new DownloadClientException($"Aria2 returned error code {fault.FaultCode}: {fault.FaultString}");
             }
 
-                throw new DownloadClientUnavailableException("Unable to connect to aria2, please check your settings", ex);
-            }
+            return doc;
         }
     }
 }

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DiskStationProxyBase.cs

@@ -1,7 +1,8 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Http;
@@ -143,15 +144,19 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
             return authResponse.Data.SId;
         }
 
-        protected HttpRequestBuilder BuildRequest(DownloadStationSettings settings, string methodName, int apiVersion, HttpMethod httpVerb = HttpMethod.GET)
+        protected HttpRequestBuilder BuildRequest(DownloadStationSettings settings, string methodName, int apiVersion, HttpMethod httpVerb = null)
         {
+            httpVerb ??= HttpMethod.Get;
+
             var info = GetApiInfo(_apiType, settings);
 
             return BuildRequest(settings, info, methodName, apiVersion, httpVerb);
         }
 
-        private HttpRequestBuilder BuildRequest(DownloadStationSettings settings, DiskStationApiInfo apiInfo, string methodName, int apiVersion, HttpMethod httpVerb = HttpMethod.GET)
+        private HttpRequestBuilder BuildRequest(DownloadStationSettings settings, DiskStationApiInfo apiInfo, string methodName, int apiVersion, HttpMethod httpVerb = null)
         {
+            httpVerb ??= HttpMethod.Get;
+
             var requestBuilder = new HttpRequestBuilder(settings.UseSsl, settings.Host, settings.Port).Resource($"webapi/{apiInfo.Path}");
             requestBuilder.Method = httpVerb;
             requestBuilder.LogResponseContent = true;
@@ -164,7 +169,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
                 throw new ArgumentOutOfRangeException(nameof(apiVersion));
             }
 
-            if (httpVerb == HttpMethod.POST)
+            if (httpVerb == HttpMethod.Post)
             {
                 if (apiInfo.NeedsAuthentication)
                 {

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DownloadStationTaskProxyV1.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Extensions;
@@ -21,7 +22,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 
         public void AddTaskFromData(byte[] data, string filename, string downloadDirectory, DownloadStationSettings settings)
         {
-            var requestBuilder = BuildRequest(settings, "create", 2, HttpMethod.POST);
+            var requestBuilder = BuildRequest(settings, "create", 2, HttpMethod.Post);
 
             if (downloadDirectory.IsNotNullOrWhiteSpace())
             {

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DownloadStationTaskProxyV2.cs

@@ -1,5 +1,6 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Extensions;
@@ -22,7 +23,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 
         public void AddTaskFromData(byte[] data, string filename, string downloadDirectory, DownloadStationSettings settings)
         {
-            var requestBuilder = BuildRequest(settings, "create", 2, HttpMethod.POST);
+            var requestBuilder = BuildRequest(settings, "create", 2, HttpMethod.Post);
 
             requestBuilder.AddFormParameter("type", "\"file\"");
             requestBuilder.AddFormParameter("file", "[\"fileData\"]");

src/NzbDrone.Core/Download/Clients/Flood/FloodProxy.cs

@@ -1,6 +1,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Http;
@@ -108,7 +109,7 @@ namespace NzbDrone.Core.Download.Clients.Flood
         {
             var verifyRequest = BuildRequest(settings).Resource("/auth/verify").Build();
 
-            verifyRequest.Method = HttpMethod.GET;
+            verifyRequest.Method = HttpMethod.Get;
 
             HandleRequest(verifyRequest, settings);
         }
@@ -181,7 +182,7 @@ namespace NzbDrone.Core.Download.Clients.Flood
         {
             var getTorrentsRequest = BuildRequest(settings).Resource("/torrents").Build();
 
-            getTorrentsRequest.Method = HttpMethod.GET;
+            getTorrentsRequest.Method = HttpMethod.Get;
 
             return Json.Deserialize<TorrentListSummary>(HandleRequest(getTorrentsRequest, settings).Content).Torrents;
         }
@@ -190,7 +191,7 @@ namespace NzbDrone.Core.Download.Clients.Flood
         {
             var contentsRequest = BuildRequest(settings).Resource($"/torrents/{hash}/contents").Build();
 
-            contentsRequest.Method = HttpMethod.GET;
+            contentsRequest.Method = HttpMethod.Get;
 
             return Json.Deserialize<List<TorrentContent>>(HandleRequest(contentsRequest, settings).Content).ConvertAll(content => content.Path);
         }
@@ -199,7 +200,7 @@ namespace NzbDrone.Core.Download.Clients.Flood
         {
             var tagsRequest = BuildRequest(settings).Resource("/torrents/tags").Build();
 
-            tagsRequest.Method = HttpMethod.PATCH;
+            tagsRequest.Method = HttpMethod.Patch;
 
             var body = new Dictionary<string, object>
             {
@@ -215,7 +216,7 @@ namespace NzbDrone.Core.Download.Clients.Flood
         {
             var contentsRequest = BuildRequest(settings).Resource($"/client/settings").Build();
 
-            contentsRequest.Method = HttpMethod.GET;
+            contentsRequest.Method = HttpMethod.Get;
 
             return Json.Deserialize<FloodClientSettings>(HandleRequest(contentsRequest, settings).Content);
         }

src/NzbDrone.Core/Download/Clients/Hadouken/HadoukenProxy.cs

@@ -74,7 +74,7 @@ namespace NzbDrone.Core.Download.Clients.Hadouken
 
             var requestBuilder = new JsonRpcRequestBuilder(baseUrl, method, parameters);
             requestBuilder.LogResponseContent = true;
-            requestBuilder.NetworkCredential = new NetworkCredential(settings.Username, settings.Password);
+            requestBuilder.NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password);
             requestBuilder.Headers.Add("Accept-Encoding", "gzip,deflate");
 
             var httpRequest = requestBuilder.Build();

src/NzbDrone.Core/Download/Clients/Nzbget/NzbgetProxy.cs

@@ -229,7 +229,7 @@ namespace NzbDrone.Core.Download.Clients.Nzbget
 
             var requestBuilder = new JsonRpcRequestBuilder(baseUrl, method, parameters);
             requestBuilder.LogResponseContent = true;
-            requestBuilder.NetworkCredential = new NetworkCredential(settings.Username, settings.Password);
+            requestBuilder.NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password);
 
             var httpRequest = requestBuilder.Build();
 

src/NzbDrone.Core/Download/Clients/QBittorrent/QBittorrentProxyV1.cs

@@ -294,7 +294,7 @@ namespace NzbDrone.Core.Download.Clients.QBittorrent
             var requestBuilder = new HttpRequestBuilder(settings.UseSsl, settings.Host, settings.Port, settings.UrlBase)
             {
                 LogResponseContent = true,
-                NetworkCredential = new NetworkCredential(settings.Username, settings.Password)
+                NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password)
             };
             return requestBuilder;
         }

src/NzbDrone.Core/Download/Clients/QBittorrent/QBittorrentProxyV2.cs

@@ -339,7 +339,7 @@ namespace NzbDrone.Core.Download.Clients.QBittorrent
             var requestBuilder = new HttpRequestBuilder(settings.UseSsl, settings.Host, settings.Port, settings.UrlBase)
             {
                 LogResponseContent = true,
-                NetworkCredential = new NetworkCredential(settings.Username, settings.Password)
+                NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password)
             };
             return requestBuilder;
         }

src/NzbDrone.Core/Download/Clients/Transmission/TransmissionProxy.cs

@@ -201,7 +201,7 @@ namespace NzbDrone.Core.Download.Clients.Transmission
                 .Accept(HttpAccept.Json);
 
             requestBuilder.LogResponseContent = true;
-            requestBuilder.NetworkCredential = new NetworkCredential(settings.Username, settings.Password);
+            requestBuilder.NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password);
             requestBuilder.AllowAutoRedirect = false;
 
             return requestBuilder;

src/NzbDrone.Core/Download/Clients/rTorrent/RTorrent.cs

@@ -132,6 +132,12 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
                     continue;
                 }
 
+                // Ignore torrents with an empty path
+                if (torrent.Path.IsNullOrWhiteSpace())
+                {
+                    continue;
+                }
+
                 if (torrent.Path.StartsWith("."))
                 {
                     throw new DownloadClientException("Download paths must be absolute. Please specify variable \"directory\" in rTorrent.");

src/NzbDrone.Core/Download/Clients/rTorrent/RTorrentFault.cs

@@ -0,0 +1,28 @@
+using System.Xml.Linq;
+using System.Xml.XPath;
+using NzbDrone.Core.Download.Extensions;
+
+namespace NzbDrone.Core.Download.Clients.RTorrent
+{
+    public class RTorrentFault
+    {
+        public RTorrentFault(XElement element)
+        {
+            foreach (var e in element.XPathSelectElements("./value/struct/member"))
+            {
+                var name = e.ElementAsString("name");
+                if (name == "faultCode")
+                {
+                    FaultCode = e.Element("value").GetIntValue();
+                }
+                else if (name == "faultString")
+                {
+                    FaultString = e.Element("value").GetStringValue();
+                }
+            }
+        }
+
+        public int FaultCode { get; set; }
+        public string FaultString { get; set; }
+    }
+}

src/NzbDrone.Core/Download/Clients/rTorrent/RTorrentProxy.cs

@@ -2,11 +2,11 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Net;
-using System.Net.Sockets;
-using System.Runtime.InteropServices.ComTypes;
-using CookComputing.XmlRpc;
-using NLog;
+using System.Xml.Linq;
+using System.Xml.XPath;
 using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Http;
+using NzbDrone.Core.Download.Extensions;
 
 namespace NzbDrone.Core.Download.Clients.RTorrent
 {
@@ -23,64 +23,27 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
         void PushTorrentUniqueView(string hash, string view, RTorrentSettings settings);
     }
 
-    public interface IRTorrent : IXmlRpcProxy
-    {
-        [XmlRpcMethod("d.multicall2")]
-        object[] TorrentMulticall(params string[] parameters);
-
-        [XmlRpcMethod("load.normal")]
-        int LoadNormal(string target, string data, params string[] commands);
-
-        [XmlRpcMethod("load.start")]
-        int LoadStart(string target, string data, params string[] commands);
-
-        [XmlRpcMethod("load.raw")]
-        int LoadRaw(string target, byte[] data, params string[] commands);
-
-        [XmlRpcMethod("load.raw_start")]
-        int LoadRawStart(string target, byte[] data, params string[] commands);
-
-        [XmlRpcMethod("d.erase")]
-        int Remove(string hash);
-
-        [XmlRpcMethod("d.name")]
-        string GetName(string hash);
-
-        [XmlRpcMethod("d.custom1.set")]
-        string SetLabel(string hash, string label);
-
-        [XmlRpcMethod("d.views.push_back_unique")]
-        int PushUniqueView(string hash, string view);
-
-        [XmlRpcMethod("system.client_version")]
-        string GetVersion();
-    }
-
     public class RTorrentProxy : IRTorrentProxy
     {
-        private readonly Logger _logger;
+        private readonly IHttpClient _httpClient;
 
-        public RTorrentProxy(Logger logger)
+        public RTorrentProxy(IHttpClient httpClient)
         {
-            _logger = logger;
+            _httpClient = httpClient;
         }
 
         public string GetVersion(RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: system.client_version");
+            var document = ExecuteRequest(settings, "system.client_version");
 
-            var client = BuildClient(settings);
-            var version = ExecuteRequest(() => client.GetVersion());
-
-            return version;
+            return document.Descendants("string").FirstOrDefault()?.Value ?? "0.0.0";
         }
 
         public List<RTorrentTorrent> GetTorrents(RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: d.multicall2");
-
-            var client = BuildClient(settings);
-            var ret = ExecuteRequest(() => client.TorrentMulticall("",
+            var document = ExecuteRequest(settings,
+                "d.multicall2",
+                "",
                 "",
                 "d.name=", // string
                 "d.hash=", // string
@@ -92,53 +55,35 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
                 "d.ratio=", // long
                 "d.is_open=", // long
                 "d.is_active=", // long
-                    "d.complete=", // long
-                    "d.timestamp.finished=")); // long (unix timestamp)
+                "d.complete=", //long
+                "d.timestamp.finished="); // long (unix timestamp)
 
-            var items = new List<RTorrentTorrent>();
+            var torrents = document.XPathSelectElement("./methodResponse/params/param/value/array/data")
+                               ?.Elements()
+                               .Select(x => new RTorrentTorrent(x))
+                               .ToList()
+                           ?? new List<RTorrentTorrent>();
 
-            foreach (object[] torrent in ret)
-            {
-                var labelDecoded = System.Web.HttpUtility.UrlDecode((string)torrent[3]);
-
-                var item = new RTorrentTorrent();
-                item.Name = (string)torrent[0];
-                item.Hash = (string)torrent[1];
-                item.Path = (string)torrent[2];
-                item.Category = labelDecoded;
-                item.TotalSize = (long)torrent[4];
-                item.RemainingSize = (long)torrent[5];
-                item.DownRate = (long)torrent[6];
-                item.Ratio = (long)torrent[7];
-                item.IsOpen = Convert.ToBoolean((long)torrent[8]);
-                item.IsActive = Convert.ToBoolean((long)torrent[9]);
-                item.IsFinished = Convert.ToBoolean((long)torrent[10]);
-                item.FinishedTime = (long)torrent[11];
-
-                items.Add(item);
-            }
-
-            return items;
+            return torrents;
         }
 
         public void AddTorrentFromUrl(string torrentUrl, string label, RTorrentPriority priority, string directory, RTorrentSettings settings)
         {
-            var client = BuildClient(settings);
-            var response = ExecuteRequest(() =>
-            {
+            var args = new List<object> { "", torrentUrl };
+            args.AddRange(GetCommands(label, priority, directory));
+
+            XDocument response;
+
             if (settings.AddStopped)
             {
-                    _logger.Debug("Executing remote method: load.normal");
-                    return client.LoadNormal("", torrentUrl, GetCommands(label, priority, directory));
+                response = ExecuteRequest(settings, "load.normal", args.ToArray());
             }
             else
             {
-                    _logger.Debug("Executing remote method: load.start");
-                    return client.LoadStart("", torrentUrl, GetCommands(label, priority, directory));
+                response = ExecuteRequest(settings, "load.start", args.ToArray());
             }
-            });
 
-            if (response != 0)
+            if (response.GetIntResponse() != 0)
             {
                 throw new DownloadClientException("Could not add torrent: {0}.", torrentUrl);
             }
@@ -146,22 +91,21 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
 
         public void AddTorrentFromFile(string fileName, byte[] fileContent, string label, RTorrentPriority priority, string directory, RTorrentSettings settings)
         {
-            var client = BuildClient(settings);
-            var response = ExecuteRequest(() =>
-            {
+            var args = new List<object> { "", fileContent };
+            args.AddRange(GetCommands(label, priority, directory));
+
+            XDocument response;
+
             if (settings.AddStopped)
             {
-                    _logger.Debug("Executing remote method: load.raw");
-                    return client.LoadRaw("", fileContent, GetCommands(label, priority, directory));
+                response = ExecuteRequest(settings, "load.raw", args.ToArray());
             }
             else
             {
-                    _logger.Debug("Executing remote method: load.raw_start");
-                    return client.LoadRawStart("", fileContent, GetCommands(label, priority, directory));
+                response = ExecuteRequest(settings, "load.raw_start", args.ToArray());
             }
-            });
 
-            if (response != 0)
+            if (response.GetIntResponse() != 0)
             {
                 throw new DownloadClientException("Could not add torrent: {0}.", fileName);
             }
@@ -169,12 +113,9 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
 
         public void SetTorrentLabel(string hash, string label, RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: d.custom1.set");
+            var response = ExecuteRequest(settings, "d.custom1.set", hash, label);
 
-            var client = BuildClient(settings);
-            var response = ExecuteRequest(() => client.SetLabel(hash, label));
-
-            if (response != label)
+            if (response.GetStringResponse() != label)
             {
                 throw new DownloadClientException("Could not set label to {1} for torrent: {0}.", hash, label);
             }
@@ -182,11 +123,9 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
 
         public void PushTorrentUniqueView(string hash, string view, RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: d.views.push_back_unique");
+            var response = ExecuteRequest(settings, "d.views.push_back_unique", hash, view);
 
-            var client = BuildClient(settings);
-            var response = ExecuteRequest(() => client.PushUniqueView(hash, view));
-            if (response != 0)
+            if (response.GetIntResponse() != 0)
             {
                 throw new DownloadClientException("Could not push unique view {0} for torrent: {1}.", view, hash);
             }
@@ -194,12 +133,9 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
 
         public void RemoveTorrent(string hash, RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: d.erase");
+            var response = ExecuteRequest(settings, "d.erase", hash);
 
-            var client = BuildClient(settings);
-            var response = ExecuteRequest(() => client.Remove(hash));
-
-            if (response != 0)
+            if (response.GetIntResponse() != 0)
             {
                 throw new DownloadClientException("Could not remove torrent: {0}.", hash);
             }
@@ -207,13 +143,10 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
 
         public bool HasHashTorrent(string hash, RTorrentSettings settings)
         {
-            _logger.Debug("Executing remote method: d.name");
-
-            var client = BuildClient(settings);
-
             try
             {
-                var name = ExecuteRequest(() => client.GetName(hash));
+                var response = ExecuteRequest(settings, "d.name", hash);
+                var name = response.GetStringResponse();
 
                 if (name.IsNullOrWhiteSpace())
                 {
@@ -252,45 +185,34 @@ namespace NzbDrone.Core.Download.Clients.RTorrent
             return result.ToArray();
         }
 
-        private IRTorrent BuildClient(RTorrentSettings settings)
+        private XDocument ExecuteRequest(RTorrentSettings settings, string methodName, params object[] args)
         {
-            var client = XmlRpcProxyGen.Create<IRTorrent>();
-
-            client.Url = string.Format(@"{0}://{1}:{2}/{3}",
-                                    settings.UseSsl ? "https" : "http",
-                                    settings.Host,
-                                    settings.Port,
-                                    settings.UrlBase);
-
-            client.EnableCompression = true;
+            var requestBuilder = new XmlRpcRequestBuilder(settings.UseSsl, settings.Host, settings.Port, settings.UrlBase)
+            {
+                LogResponseContent = true,
+            };
 
             if (!settings.Username.IsNullOrWhiteSpace())
             {
-                client.Credentials = new NetworkCredential(settings.Username, settings.Password);
+                requestBuilder.NetworkCredential = new NetworkCredential(settings.Username, settings.Password);
             }
 
-            return client;
+            var request = requestBuilder.Call(methodName, args).Build();
+
+            var response = _httpClient.Execute(request);
+
+            var doc = XDocument.Parse(response.Content);
+
+            var faultElement = doc.XPathSelectElement("./methodResponse/fault");
+
+            if (faultElement != null)
+            {
+                var fault = new RTorrentFault(faultElement);
+
+                throw new DownloadClientException($"rTorrent returned error code {fault.FaultCode}: {fault.FaultString}");
             }
 
-        private T ExecuteRequest<T>(Func<T> task)
-        {
-            try
-            {
-                return task();
-            }
-            catch (XmlRpcServerException ex)
-            {
-                throw new DownloadClientException("Unable to connect to rTorrent, please check your settings", ex);
-            }
-            catch (WebException ex)
-            {
-                if (ex.Status == WebExceptionStatus.TrustFailure)
-                {
-                    throw new DownloadClientUnavailableException("Unable to connect to rTorrent, certificate validation failed.", ex);
-                }
-
-                throw new DownloadClientUnavailableException("Unable to connect to rTorrent, please check your settings", ex);
-            }
+            return doc;
         }
     }
 }

src/NzbDrone.Core/Download/Clients/rTorrent/RTorrentTorrent.cs

@@ -1,7 +1,35 @@
-namespace NzbDrone.Core.Download.Clients.RTorrent
+using System;
+using System.Linq;
+using System.Web;
+using System.Xml.Linq;
+using NzbDrone.Core.Download.Extensions;
+
+namespace NzbDrone.Core.Download.Clients.RTorrent
 {
     public class RTorrentTorrent
     {
+        public RTorrentTorrent()
+        {
+        }
+
+        public RTorrentTorrent(XElement element)
+        {
+            var data = element.Descendants("value").ToList();
+
+            Name = data[0].GetStringValue();
+            Hash = data[1].GetStringValue();
+            Path = data[2].GetStringValue();
+            Category = HttpUtility.UrlDecode(data[3].GetStringValue());
+            TotalSize = data[4].GetLongValue();
+            RemainingSize = data[5].GetLongValue();
+            DownRate = data[6].GetLongValue();
+            Ratio = data[7].GetLongValue();
+            IsOpen = Convert.ToBoolean(data[8].GetLongValue());
+            IsActive = Convert.ToBoolean(data[9].GetLongValue());
+            IsFinished = Convert.ToBoolean(data[10].GetLongValue());
+            FinishedTime = data[11].GetLongValue();
+        }
+
         public string Name { get; set; }
         public string Hash { get; set; }
         public string Path { get; set; }

src/NzbDrone.Core/Download/Clients/uTorrent/UTorrentProxy.cs

@@ -196,7 +196,7 @@ namespace NzbDrone.Core.Download.Clients.UTorrent
                 .Accept(HttpAccept.Json);
 
             requestBuilder.LogResponseContent = true;
-            requestBuilder.NetworkCredential = new NetworkCredential(settings.Username, settings.Password);
+            requestBuilder.NetworkCredential = new BasicNetworkCredential(settings.Username, settings.Password);
 
             return requestBuilder;
         }

src/NzbDrone.Core/Download/Extensions/XmlExtensions.cs

@@ -0,0 +1,55 @@
+using System.Linq;
+using System.Xml.Linq;
+using System.Xml.XPath;
+
+namespace NzbDrone.Core.Download.Extensions
+{
+    internal static class XmlExtensions
+    {
+        public static string GetStringValue(this XElement element)
+        {
+            return element.ElementAsString("string");
+        }
+
+        public static long GetLongValue(this XElement element)
+        {
+            return element.ElementAsLong("i8");
+        }
+
+        public static int GetIntValue(this XElement element)
+        {
+            return element.ElementAsInt("i4");
+        }
+
+        public static string ElementAsString(this XElement element, XName name, bool trim = false)
+        {
+            var el = element.Element(name);
+
+            return string.IsNullOrWhiteSpace(el?.Value)
+                ? null
+                : (trim ? el.Value.Trim() : el.Value);
+        }
+
+        public static long ElementAsLong(this XElement element, XName name)
+        {
+            var el = element.Element(name);
+            return long.TryParse(el?.Value, out long value) ? value : default;
+        }
+
+        public static int ElementAsInt(this XElement element, XName name)
+        {
+            var el = element.Element(name);
+            return int.TryParse(el?.Value, out int value) ? value : default(int);
+        }
+
+        public static int GetIntResponse(this XDocument document)
+        {
+            return document.XPathSelectElement("./methodResponse/params/param/value").GetIntValue();
+        }
+
+        public static string GetStringResponse(this XDocument document)
+        {
+            return document.XPathSelectElement("./methodResponse/params/param/value").GetStringValue();
+        }
+    }
+}

src/NzbDrone.Core/Http/HttpProxySettingsProvider.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Net;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Http.Proxy;
@@ -15,7 +15,7 @@ namespace NzbDrone.Core.Http
             _configService = configService;
         }
 
-        public HttpProxySettings GetProxySettings(HttpRequest request)
+        public HttpProxySettings GetProxySettings(HttpUri uri)
         {
             var proxySettings = GetProxySettings();
             if (proxySettings == null)
@@ -23,7 +23,7 @@ namespace NzbDrone.Core.Http
                 return null;
             }
 
-            if (ShouldProxyBeBypassed(proxySettings, request.Url))
+            if (ShouldProxyBeBypassed(proxySettings, uri))
             {
                 return null;
             }

src/NzbDrone.Core/Indexers/FileList/FileListRequestGenerator.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using NzbDrone.Common.Extensions;
@@ -131,7 +131,7 @@ namespace NzbDrone.Core.Indexers.FileList
             var baseUrl = string.Format("{0}/api.php?action={1}&category={2}{3}", Settings.BaseUrl.TrimEnd('/'), searchType, categoriesQuery, parameters);
 
             var request = new IndexerRequest(baseUrl, HttpAccept.Json);
-            request.HttpRequest.AddBasicAuthentication(Settings.Username.Trim(), Settings.Passkey.Trim());
+            request.HttpRequest.Credentials = new BasicNetworkCredential(Settings.Username.Trim(), Settings.Passkey.Trim());
 
             yield return request;
         }

src/NzbDrone.Core/Indexers/HDBits/HDBitsRequestGenerator.cs

@@ -1,5 +1,6 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
 using NzbDrone.Core.IndexerSearch.Definitions;
@@ -132,7 +133,7 @@ namespace NzbDrone.Core.Indexers.HDBits
                 .Resource("/api/torrents")
                 .Build();
 
-            request.Method = HttpMethod.POST;
+            request.Method = HttpMethod.Post;
             const string appJson = "application/json";
             request.Headers.Accept = appJson;
             request.Headers.ContentType = appJson;

src/NzbDrone.Core/Notifications/Discord/DiscordProxy.cs

@@ -1,3 +1,4 @@
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
@@ -29,7 +30,7 @@ namespace NzbDrone.Core.Notifications.Discord
                     .Accept(HttpAccept.Json)
                     .Build();
 
-                request.Method = HttpMethod.POST;
+                request.Method = HttpMethod.Post;
                 request.Headers.ContentType = "application/json";
                 request.SetContent(payload.ToJson());
 

src/NzbDrone.Core/Notifications/Email/Email.cs

@@ -7,17 +7,21 @@ using MailKit.Security;
 using MimeKit;
 using NLog;
 using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Http.Dispatchers;
+using NzbDrone.Core.Security;
 
 namespace NzbDrone.Core.Notifications.Email
 {
     public class Email : NotificationBase<EmailSettings>
     {
+        private readonly ICertificateValidationService _certificateValidationService;
         private readonly Logger _logger;
 
         public override string Name => "Email";
 
-        public Email(Logger logger)
+        public Email(ICertificateValidationService certificateValidationService, Logger logger)
         {
+            _certificateValidationService = certificateValidationService;
             _logger = logger;
         }
 
@@ -124,6 +128,8 @@ namespace NzbDrone.Core.Notifications.Email
                     }
                 }
 
+                client.ServerCertificateValidationCallback = _certificateValidationService.ShouldByPassValidationError;
+
                 _logger.Debug("Connecting to mail server");
 
                 client.Connect(settings.Server, settings.Port, serverOption);

src/NzbDrone.Core/Notifications/Join/JoinProxy.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Net.Http;
 using FluentValidation.Results;
 using NLog;
 using NzbDrone.Common.Extensions;
@@ -28,7 +29,7 @@ namespace NzbDrone.Core.Notifications.Join
 
         public void SendNotification(string title, string message, JoinSettings settings)
         {
-            var method = HttpMethod.GET;
+            var method = HttpMethod.Get;
 
             try
             {

src/NzbDrone.Core/Notifications/Mailgun/MailgunProxy.cs

@@ -1,7 +1,7 @@
 using System.Net;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Http;
-using HttpMethod = NzbDrone.Common.Http.HttpMethod;
 
 namespace NzbDrone.Core.Notifications.Mailgun
 {
@@ -28,7 +28,7 @@ namespace NzbDrone.Core.Notifications.Mailgun
         {
             try
             {
-                var request = BuildRequest(settings, $"{settings.SenderDomain}/messages", HttpMethod.POST, title, message).Build();
+                var request = BuildRequest(settings, $"{settings.SenderDomain}/messages", HttpMethod.Post, title, message).Build();
                 _httpClient.Execute(request);
             }
             catch (HttpException ex)

src/NzbDrone.Core/Notifications/Plex/PlexTv/PlexTvService.cs

@@ -1,4 +1,5 @@
 using System.Linq;
+using System.Net.Http;
 using System.Text;
 using NzbDrone.Common.EnvironmentInfo;
 using NzbDrone.Common.Http;
@@ -40,7 +41,7 @@ namespace NzbDrone.Core.Notifications.Plex.PlexTv
                                  .AddQueryParam("X-Plex-Version", BuildInfo.Version.ToString())
                                  .AddQueryParam("strong", true);
 
-            requestBuilder.Method = HttpMethod.POST;
+            requestBuilder.Method = HttpMethod.Post;
 
             var request = requestBuilder.Build();
 

src/NzbDrone.Core/Notifications/Plex/Server/PlexServerProxy.cs

@@ -1,6 +1,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.EnvironmentInfo;
 using NzbDrone.Common.Extensions;
@@ -35,7 +36,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         public List<PlexSection> GetTvSections(PlexServerSettings settings)
         {
-            var request = BuildRequest("library/sections", HttpMethod.GET, settings);
+            var request = BuildRequest("library/sections", HttpMethod.Get, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);
@@ -65,7 +66,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
         public void Update(int sectionId, PlexServerSettings settings)
         {
             var resource = $"library/sections/{sectionId}/refresh";
-            var request = BuildRequest(resource, HttpMethod.GET, settings);
+            var request = BuildRequest(resource, HttpMethod.Get, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);
@@ -74,7 +75,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
         public void UpdateSeries(string metadataId, PlexServerSettings settings)
         {
             var resource = $"library/metadata/{metadataId}/refresh";
-            var request = BuildRequest(resource, HttpMethod.PUT, settings);
+            var request = BuildRequest(resource, HttpMethod.Put, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);
@@ -82,7 +83,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         public string Version(PlexServerSettings settings)
         {
-            var request = BuildRequest("identity", HttpMethod.GET, settings);
+            var request = BuildRequest("identity", HttpMethod.Get, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);
@@ -100,7 +101,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         public List<PlexPreference> Preferences(PlexServerSettings settings)
         {
-            var request = BuildRequest(":/prefs", HttpMethod.GET, settings);
+            var request = BuildRequest(":/prefs", HttpMethod.Get, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);
@@ -120,7 +121,7 @@ namespace NzbDrone.Core.Notifications.Plex.Server
         {
             var guid = $"com.plexapp.agents.thetvdb://{tvdbId}?lang={language}";
             var resource = $"library/sections/{sectionId}/all?guid={System.Web.HttpUtility.UrlEncode(guid)}";
-            var request = BuildRequest(resource, HttpMethod.GET, settings);
+            var request = BuildRequest(resource, HttpMethod.Get, settings);
             var response = ProcessRequest(request);
 
             CheckForError(response);

src/NzbDrone.Core/Notifications/PushBullet/PushBulletProxy.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Net;
+using System.Net.Http;
 using FluentValidation.Results;
 using NLog;
 using NzbDrone.Common.Extensions;
@@ -100,8 +101,8 @@ namespace NzbDrone.Core.Notifications.PushBullet
 
                 var request = requestBuilder.Build();
 
-                request.Method = HttpMethod.GET;
-                request.AddBasicAuthentication(settings.ApiKey, string.Empty);
+                request.Method = HttpMethod.Get;
+                request.Credentials = new BasicNetworkCredential(settings.ApiKey, string.Empty);
 
                 var response = _httpClient.Execute(request);
 
@@ -197,7 +198,7 @@ namespace NzbDrone.Core.Notifications.PushBullet
 
                 var request = requestBuilder.Build();
 
-                request.AddBasicAuthentication(settings.ApiKey, string.Empty);
+                request.Credentials = new BasicNetworkCredential(settings.ApiKey, string.Empty);
 
                 _httpClient.Execute(request);
             }

src/NzbDrone.Core/Notifications/SendGrid/SendGridProxy.cs

@@ -1,4 +1,5 @@
-using System.Net;
+using System.Net;
+using System.Net.Http;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
 
@@ -22,7 +23,7 @@ namespace NzbDrone.Core.Notifications.SendGrid
         {
             try
             {
-                var request = BuildRequest(settings, "mail/send", HttpMethod.POST);
+                var request = BuildRequest(settings, "mail/send", HttpMethod.Post);
 
                 var payload = new SendGridPayload
                 {

src/NzbDrone.Core/Notifications/Slack/SlackProxy.cs

@@ -1,3 +1,4 @@
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
@@ -29,7 +30,7 @@ namespace NzbDrone.Core.Notifications.Slack
                     .Accept(HttpAccept.Json)
                     .Build();
 
-                request.Method = HttpMethod.POST;
+                request.Method = HttpMethod.Post;
                 request.Headers.ContentType = "application/json";
                 request.SetContent(payload.ToJson());
 

src/NzbDrone.Core/Notifications/Trakt/TraktProxy.cs

@@ -1,3 +1,4 @@
+using System.Net.Http;
 using NLog;
 using NzbDrone.Common.Extensions;
 using NzbDrone.Common.Http;
@@ -35,7 +36,7 @@ namespace NzbDrone.Core.Notifications.Trakt
 
         public void AddToCollection(TraktCollectShowsResource payload, string accessToken)
         {
-            var request = BuildTraktRequest("sync/collection", HttpMethod.POST, accessToken);
+            var request = BuildTraktRequest("sync/collection", HttpMethod.Post, accessToken);
 
             request.Headers.ContentType = "application/json";
             request.SetContent(payload.ToJson());
@@ -53,7 +54,7 @@ namespace NzbDrone.Core.Notifications.Trakt
 
         public void RemoveFromCollection(TraktCollectShowsResource payload, string accessToken)
         {
-            var request = BuildTraktRequest("sync/collection/remove", HttpMethod.POST, accessToken);
+            var request = BuildTraktRequest("sync/collection/remove", HttpMethod.Post, accessToken);
 
             request.Headers.ContentType = "application/json";
             var temp = payload.ToJson();
@@ -72,7 +73,7 @@ namespace NzbDrone.Core.Notifications.Trakt
 
         public string GetUserName(string accessToken)
         {
-            var request = BuildTraktRequest("users/settings", HttpMethod.GET, accessToken);
+            var request = BuildTraktRequest("users/settings", HttpMethod.Get, accessToken);
 
             try
             {

src/NzbDrone.Core/Notifications/Twitter/TwitterProxy.cs

@@ -0,0 +1,110 @@
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Linq;
+using System.Net.Http;
+using System.Text;
+using System.Web;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Http;
+using NzbDrone.Common.OAuth;
+
+namespace NzbDrone.Core.Notifications.Twitter
+{
+    public interface ITwitterProxy
+    {
+        NameValueCollection GetOAuthToken(string consumerKey, string consumerSecret, string oauthToken, string oauthVerifier);
+        string GetOAuthRedirect(string consumerKey, string consumerSecret, string callbackUrl);
+        void UpdateStatus(string message, TwitterSettings settings);
+        void DirectMessage(string message, TwitterSettings settings);
+    }
+
+    public class TwitterProxy : ITwitterProxy
+    {
+        private readonly IHttpClient _httpClient;
+
+        public TwitterProxy(IHttpClient httpClient)
+        {
+            _httpClient = httpClient;
+        }
+
+        public string GetOAuthRedirect(string consumerKey, string consumerSecret, string callbackUrl)
+        {
+            // Creating a new instance with a helper method
+            var oAuthRequest = OAuthRequest.ForRequestToken(consumerKey, consumerSecret, callbackUrl);
+            oAuthRequest.RequestUrl = "https://api.twitter.com/oauth/request_token";
+            var qscoll = HttpUtility.ParseQueryString(ExecuteRequest(GetRequest(oAuthRequest, new Dictionary<string, string>())).Content);
+
+            return string.Format("https://api.twitter.com/oauth/authorize?oauth_token={0}", qscoll["oauth_token"]);
+        }
+
+        public NameValueCollection GetOAuthToken(string consumerKey, string consumerSecret, string oauthToken, string oauthVerifier)
+        {
+            // Creating a new instance with a helper method
+            var oAuthRequest = OAuthRequest.ForAccessToken(consumerKey, consumerSecret, oauthToken, "", oauthVerifier);
+            oAuthRequest.RequestUrl = "https://api.twitter.com/oauth/access_token";
+
+            return HttpUtility.ParseQueryString(ExecuteRequest(GetRequest(oAuthRequest, new Dictionary<string, string>())).Content);
+        }
+
+        public void UpdateStatus(string message, TwitterSettings settings)
+        {
+            var oAuthRequest = OAuthRequest.ForProtectedResource("POST", settings.ConsumerKey, settings.ConsumerSecret, settings.AccessToken, settings.AccessTokenSecret);
+
+            oAuthRequest.RequestUrl = "https://api.twitter.com/1.1/statuses/update.json";
+
+            var customParams = new Dictionary<string, string>
+            {
+                { "status", message.EncodeRFC3986() }
+            };
+
+            var request = GetRequest(oAuthRequest, customParams);
+
+            request.Headers.ContentType = "application/x-www-form-urlencoded";
+            request.SetContent(Encoding.ASCII.GetBytes(GetCustomParametersString(customParams)));
+
+            ExecuteRequest(request);
+        }
+
+        public void DirectMessage(string message, TwitterSettings settings)
+        {
+            var oAuthRequest = OAuthRequest.ForProtectedResource("POST", settings.ConsumerKey, settings.ConsumerSecret, settings.AccessToken, settings.AccessTokenSecret);
+
+            oAuthRequest.RequestUrl = "https://api.twitter.com/1.1/direct_messages/new.json";
+
+            var customParams = new Dictionary<string, string>
+            {
+                { "text", message.EncodeRFC3986() },
+                { "screenname", settings.Mention.EncodeRFC3986() }
+            };
+
+            var request = GetRequest(oAuthRequest, customParams);
+
+            request.Headers.ContentType = "application/x-www-form-urlencoded";
+            request.SetContent(Encoding.ASCII.GetBytes(GetCustomParametersString(customParams)));
+
+            ExecuteRequest(request);
+        }
+
+        private string GetCustomParametersString(Dictionary<string, string> customParams)
+        {
+            return customParams.Select(x => string.Format("{0}={1}", x.Key, x.Value)).Join("&");
+        }
+
+        private HttpRequest GetRequest(OAuthRequest oAuthRequest, Dictionary<string, string> customParams)
+        {
+            var auth = oAuthRequest.GetAuthorizationHeader(customParams);
+            var request = new HttpRequest(oAuthRequest.RequestUrl);
+
+            request.Headers.Add("Authorization", auth);
+
+            request.Method = oAuthRequest.Method == "POST" ? HttpMethod.Post : HttpMethod.Get;
+
+            return request;
+        }
+
+        private HttpResponse ExecuteRequest(HttpRequest request)
+        {
+            return _httpClient.Execute(request);
+        }
+    }
+}

src/NzbDrone.Core/Notifications/Twitter/TwitterService.cs

@@ -1,13 +1,9 @@
-using System;
-using System.Collections.Specialized;
+using System;
 using System.IO;
 using System.Net;
-using System.Web;
 using FluentValidation.Results;
 using NLog;
 using NzbDrone.Common.Extensions;
-using NzbDrone.Common.Http;
-using NzbDrone.Common.OAuth;
 
 namespace NzbDrone.Core.Notifications.Twitter
 {
@@ -21,31 +17,18 @@ namespace NzbDrone.Core.Notifications.Twitter
 
     public class TwitterService : ITwitterService
     {
-        private readonly IHttpClient _httpClient;
+        private readonly ITwitterProxy _twitterProxy;
         private readonly Logger _logger;
 
-        public TwitterService(IHttpClient httpClient, Logger logger)
+        public TwitterService(ITwitterProxy twitterProxy, Logger logger)
         {
-            _httpClient = httpClient;
+            _twitterProxy = twitterProxy;
             _logger = logger;
         }
 
-        private NameValueCollection OAuthQuery(OAuthRequest oAuthRequest)
-        {
-            var auth = oAuthRequest.GetAuthorizationHeader();
-            var request = new Common.Http.HttpRequest(oAuthRequest.RequestUrl);
-            request.Headers.Add("Authorization", auth);
-            var response = _httpClient.Get(request);
-
-            return HttpUtility.ParseQueryString(response.Content);
-        }
-
         public OAuthToken GetOAuthToken(string consumerKey, string consumerSecret, string oauthToken, string oauthVerifier)
         {
-            // Creating a new instance with a helper method
-            var oAuthRequest = OAuthRequest.ForAccessToken(consumerKey, consumerSecret, oauthToken, "", oauthVerifier);
-            oAuthRequest.RequestUrl = "https://api.twitter.com/oauth/access_token";
-            var qscoll = OAuthQuery(oAuthRequest);
+            var qscoll = _twitterProxy.GetOAuthToken(consumerKey, consumerSecret, oauthToken, oauthVerifier);
 
             return new OAuthToken
             {
@@ -56,31 +39,16 @@ namespace NzbDrone.Core.Notifications.Twitter
 
         public string GetOAuthRedirect(string consumerKey, string consumerSecret, string callbackUrl)
         {
-            // Creating a new instance with a helper method
-            var oAuthRequest = OAuthRequest.ForRequestToken(consumerKey, consumerSecret, callbackUrl);
-            oAuthRequest.RequestUrl = "https://api.twitter.com/oauth/request_token";
-            var qscoll = OAuthQuery(oAuthRequest);
-
-            return string.Format("https://api.twitter.com/oauth/authorize?oauth_token={0}", qscoll["oauth_token"]);
+            return _twitterProxy.GetOAuthRedirect(consumerKey, consumerSecret, callbackUrl);
         }
 
         public void SendNotification(string message, TwitterSettings settings)
         {
             try
             {
-                var oAuth = new TinyTwitter.OAuthInfo
-                {
-                    ConsumerKey = settings.ConsumerKey,
-                    ConsumerSecret = settings.ConsumerSecret,
-                    AccessToken = settings.AccessToken,
-                    AccessSecret = settings.AccessTokenSecret
-                };
-
-                var twitter = new TinyTwitter.TinyTwitter(oAuth);
-
                 if (settings.DirectMessage)
                 {
-                    twitter.DirectMessage(message, settings.Mention);
+                    _twitterProxy.DirectMessage(message, settings);
                 }
                 else
                 {
@@ -89,7 +57,7 @@ namespace NzbDrone.Core.Notifications.Twitter
                         message += string.Format(" @{0}", settings.Mention);
                     }
 
-                    twitter.UpdateStatus(message);
+                    _twitterProxy.UpdateStatus(message, settings);
                 }
             }
             catch (WebException ex)

src/NzbDrone.Core/Notifications/Webhook/WebhookMethod.cs

@@ -1,10 +1,10 @@
-using NzbDrone.Common.Http;
+using NzbDrone.Common.Http;
 
 namespace NzbDrone.Core.Notifications.Webhook
 {
     public enum WebhookMethod
     {
-        POST = HttpMethod.POST,
-        PUT = HttpMethod.PUT
+        POST = 1,
+        PUT = 2
     }
 }

src/NzbDrone.Core/Notifications/Webhook/WebhookProxy.cs

@@ -1,3 +1,5 @@
+using System;
+using System.Net.Http;
 using NzbDrone.Common.Extensions;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
@@ -26,13 +28,19 @@ namespace NzbDrone.Core.Notifications.Webhook
                     .Accept(HttpAccept.Json)
                     .Build();
 
-                request.Method = (HttpMethod)settings.Method;
+                request.Method = settings.Method switch
+                {
+                    (int)WebhookMethod.POST => HttpMethod.Post,
+                    (int)WebhookMethod.PUT => HttpMethod.Put,
+                    _ => throw new ArgumentOutOfRangeException($"Invalid Webhook method {settings.Method}")
+                };
+
                 request.Headers.ContentType = "application/json";
                 request.SetContent(body.ToJson());
 
                 if (settings.Username.IsNotNullOrWhiteSpace() || settings.Password.IsNotNullOrWhiteSpace())
                 {
-                    request.AddBasicAuthentication(settings.Username, settings.Password);
+                    request.Credentials = new BasicNetworkCredential(settings.Username, settings.Password);
                 }
 
                 _httpClient.Execute(request);

src/NzbDrone.Core/Notifications/Xbmc/XbmcJsonApiProxy.cs

@@ -84,7 +84,7 @@ namespace NzbDrone.Core.Notifications.Xbmc
 
             if (!settings.Username.IsNullOrWhiteSpace())
             {
-                request.AddBasicAuthentication(settings.Username, settings.Password);
+                request.Credentials = new BasicNetworkCredential(settings.Username, settings.Password);
             }
 
             var response = _httpClient.Execute(request);

src/NzbDrone.Core/Security/X509CertificateValidationService.cs

@@ -1,16 +1,15 @@
-using System.Linq;
+using System.Linq;
 using System.Net;
 using System.Net.Security;
 using System.Security.Cryptography.X509Certificates;
 using NLog;
 using NzbDrone.Common.Extensions;
+using NzbDrone.Common.Http.Dispatchers;
 using NzbDrone.Core.Configuration;
-using NzbDrone.Core.Lifecycle;
-using NzbDrone.Core.Messaging.Events;
 
 namespace NzbDrone.Core.Security
 {
-    public class X509CertificateValidationService : IHandle<ApplicationStartedEvent>
+    public class X509CertificateValidationService : ICertificateValidationService
     {
         private readonly IConfigService _configService;
         private readonly Logger _logger;
@@ -21,19 +20,29 @@ namespace NzbDrone.Core.Security
             _logger = logger;
         }
 
-        private bool ShouldByPassValidationError(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
+        public bool ShouldByPassValidationError(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
         {
-            var request = sender as HttpWebRequest;
+            var targetHostName = string.Empty;
 
-            if (request == null)
+            if (sender is not SslStream && sender is not string)
             {
                 return true;
             }
 
-            var cert2 = certificate as X509Certificate2;
-            if (cert2 != null && request != null && cert2.SignatureAlgorithm.FriendlyName == "md5RSA")
+            if (sender is SslStream request)
             {
-                _logger.Error("https://{0} uses the obsolete md5 hash in it's https certificate, if that is your certificate, please (re)create certificate with better algorithm as soon as possible.", request.RequestUri.Authority);
+                targetHostName = request.TargetHostName;
+            }
+
+            // Mailkit passes host in sender as string
+            if (sender is string stringHost)
+            {
+                targetHostName = stringHost;
+            }
+
+            if (certificate is X509Certificate2 cert2 && cert2.SignatureAlgorithm.FriendlyName == "md5RSA")
+            {
+                _logger.Error("https://{0} uses the obsolete md5 hash in it's https certificate, if that is your certificate, please (re)create certificate with better algorithm as soon as possible.", targetHostName);
             }
 
             if (sslPolicyErrors == SslPolicyErrors.None)
@@ -41,12 +50,12 @@ namespace NzbDrone.Core.Security
                 return true;
             }
 
-            if (request.RequestUri.Host == "localhost" || request.RequestUri.Host == "127.0.0.1")
+            if (targetHostName == "localhost" || targetHostName == "127.0.0.1")
             {
                 return true;
             }
 
-            var ipAddresses = GetIPAddresses(request.RequestUri.Host);
+            var ipAddresses = GetIPAddresses(targetHostName);
             var certificateValidation = _configService.CertificateValidation;
 
             if (certificateValidation == CertificateValidationType.Disabled)
@@ -60,7 +69,7 @@ namespace NzbDrone.Core.Security
                 return true;
             }
 
-            _logger.Error("Certificate validation for {0} failed. {1}", request.Address, sslPolicyErrors);
+            _logger.Error("Certificate validation for {0} failed. {1}", targetHostName, sslPolicyErrors);
 
             return false;
         }
@@ -74,10 +83,5 @@ namespace NzbDrone.Core.Security
 
             return Dns.GetHostEntry(host).AddressList;
         }
-
-        public void Handle(ApplicationStartedEvent message)
-        {
-            ServicePointManager.ServerCertificateValidationCallback = ShouldByPassValidationError;
-        }
     }
 }

src/NzbDrone.Core/Sonarr.Core.csproj

@@ -15,7 +15,6 @@
     <PackageReference Include="SixLabors.ImageSharp" Version="1.0.1" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="NLog" Version="4.7.14" />
-    <PackageReference Include="Kveer.XmlRPC" Version="1.2.0" />
     <PackageReference Include="MonoTorrent" Version="2.0.5" />
     <PackageReference Include="System.Data.SQLite.Core.Servarr" Version="1.0.115.5-18" />
     <PackageReference Include="System.Text.Json" Version="6.0.4" />

src/NzbDrone.Core/TinyTwitter.cs

@@ -1,238 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Net;
-using System.Security.Cryptography;
-using System.Text;
-using System.Text.RegularExpressions;
-using Newtonsoft.Json;
-
-namespace TinyTwitter
-{
-    public class OAuthInfo
-    {
-        public string ConsumerKey { get; set; }
-        public string ConsumerSecret { get; set; }
-        public string AccessToken { get; set; }
-        public string AccessSecret { get; set; }
-    }
-
-    public class Tweet
-    {
-        public long Id { get; set; }
-        public DateTime CreatedAt { get; set; }
-        public string UserName { get; set; }
-        public string ScreenName { get; set; }
-        public string Text { get; set; }
-    }
-
-    public class TinyTwitter
-    {
-        private readonly OAuthInfo _oauth;
-
-        public TinyTwitter(OAuthInfo oauth)
-        {
-            _oauth = oauth;
-        }
-
-        public void UpdateStatus(string message)
-        {
-            new RequestBuilder(_oauth, "POST", "https://api.twitter.com/1.1/statuses/update.json")
-                .AddParameter("status", message)
-                .Execute();
-        }
-
-        /**
-         *
-         * As of June 26th 2015 Direct Messaging is not part of TinyTwitter.
-         * I have added it to Sonarr's copy to make our implementation easier
-         * and added this banner so it's not blindly updated.
-         *
-         **/
-        public void DirectMessage(string message, string screenName)
-        {
-            new RequestBuilder(_oauth, "POST", "https://api.twitter.com/1.1/direct_messages/new.json")
-                .AddParameter("text", message)
-                .AddParameter("screen_name", screenName)
-                .Execute();
-        }
-
-        public class RequestBuilder
-        {
-            private const string VERSION = "1.0";
-            private const string SIGNATURE_METHOD = "HMAC-SHA1";
-
-            private readonly OAuthInfo _oauth;
-            private readonly string _method;
-            private readonly IDictionary<string, string> _customParameters;
-            private readonly string _url;
-
-            public RequestBuilder(OAuthInfo oauth, string method, string url)
-            {
-                _oauth = oauth;
-                _method = method;
-                _url = url;
-                _customParameters = new Dictionary<string, string>();
-            }
-
-            public RequestBuilder AddParameter(string name, string value)
-            {
-                _customParameters.Add(name, value.EncodeRFC3986());
-                return this;
-            }
-
-            public string Execute()
-            {
-                var timespan = GetTimestamp();
-                var nonce = CreateNonce();
-
-                var parameters = new Dictionary<string, string>(_customParameters);
-                AddOAuthParameters(parameters, timespan, nonce);
-
-                var signature = GenerateSignature(parameters);
-                var headerValue = GenerateAuthorizationHeaderValue(parameters, signature);
-
-                var request = (HttpWebRequest)WebRequest.Create(GetRequestUrl());
-                request.Method = _method;
-                request.ContentType = "application/x-www-form-urlencoded";
-
-                request.Headers.Add("Authorization", headerValue);
-
-                WriteRequestBody(request);
-
-                // It looks like a bug in HttpWebRequest. It throws random TimeoutExceptions
-                // after some requests. Abort the request seems to work. More info:
-                // http://stackoverflow.com/questions/2252762/getrequeststream-throws-timeout-exception-randomly
-
-                var response = request.GetResponse();
-
-                string content;
-
-                using (var stream = response.GetResponseStream())
-                {
-                    using (var reader = new StreamReader(stream))
-                    {
-                        content = reader.ReadToEnd();
-                    }
-                }
-
-                request.Abort();
-
-                return content;
-            }
-
-            private void WriteRequestBody(HttpWebRequest request)
-            {
-                if (_method == "GET")
-                {
-                    return;
-                }
-
-                var requestBody = Encoding.ASCII.GetBytes(GetCustomParametersString());
-                using (var stream = request.GetRequestStream())
-                {
-                    stream.Write(requestBody, 0, requestBody.Length);
-                }
-            }
-
-            private string GetRequestUrl()
-            {
-                if (_method != "GET" || _customParameters.Count == 0)
-                {
-                    return _url;
-                }
-
-                return string.Format("{0}?{1}", _url, GetCustomParametersString());
-            }
-
-            private string GetCustomParametersString()
-            {
-                return _customParameters.Select(x => string.Format("{0}={1}", x.Key, x.Value)).Join("&");
-            }
-
-            private string GenerateAuthorizationHeaderValue(IEnumerable<KeyValuePair<string, string>> parameters, string signature)
-            {
-                return new StringBuilder("OAuth ")
-                    .Append(parameters.Concat(new KeyValuePair<string, string>("oauth_signature", signature))
-                                .Where(x => x.Key.StartsWith("oauth_"))
-                                .Select(x => string.Format("{0}=\"{1}\"", x.Key, x.Value.EncodeRFC3986()))
-                                .Join(","))
-                    .ToString();
-            }
-
-            private string GenerateSignature(IEnumerable<KeyValuePair<string, string>> parameters)
-            {
-                var dataToSign = new StringBuilder()
-                    .Append(_method).Append('&')
-                    .Append(_url.EncodeRFC3986()).Append('&')
-                    .Append(parameters
-                                .OrderBy(x => x.Key)
-                                .Select(x => string.Format("{0}={1}", x.Key, x.Value))
-                                .Join("&")
-                                .EncodeRFC3986());
-
-                var signatureKey = string.Format("{0}&{1}", _oauth.ConsumerSecret.EncodeRFC3986(), _oauth.AccessSecret.EncodeRFC3986());
-                var sha1 = new HMACSHA1(Encoding.ASCII.GetBytes(signatureKey));
-
-                var signatureBytes = sha1.ComputeHash(Encoding.ASCII.GetBytes(dataToSign.ToString()));
-                return Convert.ToBase64String(signatureBytes);
-            }
-
-            private void AddOAuthParameters(IDictionary<string, string> parameters, string timestamp, string nonce)
-            {
-                parameters.Add("oauth_version", VERSION);
-                parameters.Add("oauth_consumer_key", _oauth.ConsumerKey);
-                parameters.Add("oauth_nonce", nonce);
-                parameters.Add("oauth_signature_method", SIGNATURE_METHOD);
-                parameters.Add("oauth_timestamp", timestamp);
-                parameters.Add("oauth_token", _oauth.AccessToken);
-            }
-
-            private static string GetTimestamp()
-            {
-                return ((int)(DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds).ToString();
-            }
-
-            private static string CreateNonce()
-            {
-                return new Random().Next(0x0000000, 0x7fffffff).ToString("X8");
-            }
-        }
-    }
-
-    public static class TinyTwitterHelperExtensions
-    {
-        public static string Join<T>(this IEnumerable<T> items, string separator)
-        {
-            return string.Join(separator, items.ToArray());
-        }
-
-        public static IEnumerable<T> Concat<T>(this IEnumerable<T> items, T value)
-        {
-            return items.Concat(new[] { value });
-        }
-
-        public static string EncodeRFC3986(this string value)
-        {
-            // From Twitterizer http://www.twitterizer.net/
-
-            if (string.IsNullOrEmpty(value))
-            {
-                return string.Empty;
-            }
-
-            var encoded = Uri.EscapeDataString(value);
-
-            return Regex
-                .Replace(encoded, "(%[0-9a-f][0-9a-f])", c => c.Value.ToUpper())
-                .Replace("(", "%28")
-                .Replace(")", "%29")
-                .Replace("$", "%24")
-                .Replace("!", "%21")
-                .Replace("*", "%2A")
-                .Replace("'", "%27")
-                .Replace("%7E", "~");
-        }
-    }
-}

src/NzbDrone.Integration.Test/IndexHtmlFixture.cs

@@ -1,5 +1,8 @@
-using System.Linq;
+using System;
+using System.Linq;
 using System.Net;
+using System.Net.Http;
+using System.Net.Http.Headers;
 using FluentAssertions;
 using NUnit.Framework;
 
@@ -8,25 +11,30 @@ namespace NzbDrone.Integration.Test
     [TestFixture]
     public class IndexHtmlFixture : IntegrationTest
     {
+        private HttpClient _httpClient = new HttpClient();
+
         [Test]
         public void should_get_index_html()
         {
-            var text = new WebClient().DownloadString(RootUrl);
+            var request = new HttpRequestMessage(HttpMethod.Get, RootUrl);
+            var response = _httpClient.Send(request);
+            var text = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
             text.Should().NotBeNullOrWhiteSpace();
         }
 
         [Test]
         public void index_should_not_be_cached()
         {
-            var client = new WebClient();
-            _ = client.DownloadString(RootUrl);
+            var request = new HttpRequestMessage(HttpMethod.Get, RootUrl);
+            var response = _httpClient.Send(request);
 
-            var headers = client.ResponseHeaders;
+            var headers = response.Headers;
 
-            headers.Get("Cache-Control").Split(',').Select(x => x.Trim())
-                .Should().BeEquivalentTo("no-store, no-cache".Split(',').Select(x => x.Trim()));
-            headers.Get("Pragma").Should().Be("no-cache");
-            headers.Get("Expires").Should().Be("-1");
+            headers.CacheControl.NoStore.Should().BeTrue();
+            headers.CacheControl.NoCache.Should().BeTrue();
+            headers.Pragma.Should().Contain(new NameValueHeaderValue("no-cache"));
+
+            response.Content.Headers.Expires.Should().BeBefore(DateTime.UtcNow);
         }
     }
 }