add tcp keep alive hack to net5 target

.github/workflows/buildtest.yaml

@@ -28,7 +28,7 @@ jobs:
       - name: Check Format
         # don't check formatting on Windows b/c of CRLF issues.
         if: matrix.os != 'windows-latest'
-        run: dotnet format --check --dry-run --exclude ./src/KubernetesClient/generated/
+        run: dotnet format --check --exclude ./src/KubernetesClient/generated/
       - name: Build
         run: dotnet build --configuration Release
       - name: Test

src/KubernetesClient/Kubernetes.ConfigInit.cs

@@ -4,6 +4,8 @@
 using System.Net;
 using System.Net.Http;
 using System.Net.Security;
+using System.Net.Sockets;
+using System.Reflection;
 using System.Security.Cryptography.X509Certificates;
 using k8s.Exceptions;
 using k8s.Models;
@@ -166,6 +168,39 @@ private void AppendDelegatingHandler<T>()
         private void CreateHttpClient(DelegatingHandler[] handlers)
         {
             FirstMessageHandler = HttpClientHandler = CreateRootHandler();
+
+
+#if NET5_0
+
+            // https://github.com/kubernetes-client/csharp/issues/533
+            // net5 only
+            // this is a temp fix to attach SocketsHttpHandler to HttpClient in order to set SO_KEEPALIVE
+            // https://tldp.org/HOWTO/html_single/TCP-Keepalive-HOWTO/
+            //
+            // _underlyingHandler is not a public accessible field
+            // src of net5 HttpClientHandler and _underlyingHandler field defined here
+            // https://github.com/dotnet/runtime/blob/79ae74f5ca5c8a6fe3a48935e85bd7374959c570/src/libraries/System.Net.Http/src/System/Net/Http/HttpClientHandler.cs#L22
+            //
+            // Should remove after better solution
+
+            var sh = new SocketsHttpHandler();
+            sh.ConnectCallback = async (context, token) =>
+            {
+                var socket = new Socket(SocketType.Stream, ProtocolType.Tcp)
+                {
+                    NoDelay = true,
+                };
+
+                socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);
+
+                await socket.ConnectAsync(context.DnsEndPoint.Host, context.DnsEndPoint.Port, token).ConfigureAwait(false);
+                return new NetworkStream(socket, ownsSocket: true);
+            };
+
+            var p = HttpClientHandler.GetType().GetField("_underlyingHandler", BindingFlags.NonPublic | BindingFlags.Instance);
+            p.SetValue(HttpClientHandler, (sh));
+#endif
+
             if (handlers == null || handlers.Length == 0)
             {
                 // ensure we have at least one DelegatingHandler so AppendDelegatingHandler will work

src/KubernetesClient/Kubernetes.Watch.cs

@@ -151,7 +151,11 @@ public async Task<Watcher<T>> WatchObjectAsync<T>(string path, string @continue
                     httpResponse.StatusCode));
                 if (httpResponse.Content != null)
                 {
+#if NET5_0
+                    responseContent = await httpResponse.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false);
+#else
                     responseContent = await httpResponse.Content.ReadAsStringAsync().ConfigureAwait(false);
+#endif
                 }
 
                 ex.Request = new HttpRequestMessageWrapper(httpRequest, responseContent);

src/KubernetesClient/Kubernetes.WebSocket.cs

@@ -319,7 +319,7 @@ protected async Task<WebSocket> StreamConnectAsync(Uri uri, string invocationId
             }
 #endif
 
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET5_0
             if (this.CaCerts != null)
             {
                 webSocketBuilder.ExpectServerCertificate(this.CaCerts);
@@ -334,7 +334,7 @@ protected async Task<WebSocket> StreamConnectAsync(Uri uri, string invocationId
             {
                 webSocketBuilder.Options.AddSubProtocol(webSocketSubProtocol);
             }
-#endif // NETSTANDARD2_1
+#endif // NETSTANDARD2_1 || NET5_0
 
             // Send Request
             cancellationToken.ThrowIfCancellationRequested();
@@ -366,8 +366,11 @@ protected async Task<WebSocket> StreamConnectAsync(Uri uri, string invocationId
                 }
                 else
                 {
+#if NET5_0
+                    var content = await response.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false);
+#else
                     var content = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
-
+#endif
                     // Try to parse the content as a V1Status object
                     var genericObject = SafeJsonConvert.DeserializeObject<KubernetesObject>(content);
                     V1Status status = null;

src/KubernetesClient/KubernetesClient.csproj

@@ -9,7 +9,7 @@
     <PackageIconUrl>https://raw.githubusercontent.com/kubernetes/kubernetes/master/logo/logo.png</PackageIconUrl>
     <PackageTags>kubernetes;docker;containers;</PackageTags>
 
-    <TargetFrameworks>netstandard2.0;netstandard2.1</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;netstandard2.1;net5</TargetFrameworks>
     <RootNamespace>k8s</RootNamespace>
     <SignAssembly>true</SignAssembly>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>

src/KubernetesClient/WebSocketBuilder.cs

@@ -50,7 +50,7 @@ public void CleanupServerCertificateValidationCallback(RemoteCertificateValidati
         }
 #endif
 
-#if NETSTANDARD2_1
+#if NETSTANDARD2_1 || NET5_0
         public WebSocketBuilder ExpectServerCertificate(X509Certificate2Collection serverCertificate)
         {
             Options.RemoteCertificateValidationCallback
@@ -70,7 +70,7 @@ public WebSocketBuilder SkipServerCertificateValidation()
             return this;
         }
 
-#endif // NETSTANDARD2_1
+#endif // NETSTANDARD2_1 || NET5_0
 
         public virtual async Task<WebSocket> BuildAndConnectAsync(Uri uri, CancellationToken cancellationToken)
         {

tests/KubernetesClient.Tests/AuthTests.cs

@@ -165,7 +165,7 @@ public void BasicAuth()
             }
         }
 
-#if NETSTANDARD2_1 // The functionality under test, here, is dependent on managed HTTP / WebSocket in .NET Core 2.1 or newer.
+#if NETSTANDARD2_1 || NET5_0 // The functionality under test, here, is dependent on managed HTTP / WebSocket in .NET Core 2.1 or newer.
         // this test doesn't work on OSX and is inconsistent on windows
         [OperatingSystemDependentFact(Exclude = OperatingSystems.OSX | OperatingSystems.Windows)]
         public void Cert()
@@ -338,7 +338,7 @@ public void ExternalCertificate()
                 }
             }
         }
-#endif // NETSTANDARD2_1
+#endif // NETSTANDARD2_1 || NET5_0
 
         [Fact]
         public void ExternalToken()

tests/KubernetesClient.Tests/KubernetesExecTests.cs

@@ -1,4 +1,4 @@
-#if !NETSTANDARD2_1
+#if !NETSTANDARD2_1 || NET5_0
 /*
  * These tests are only for the netstandard version of the client (there are separate tests for netcoreapp that connect to a local test-hosted server).
  */

tests/KubernetesClient.Tests/Mock/MockWebSocketBuilder.cs

@@ -1,4 +1,4 @@
-#if !NETSTANDARD2_1
+#if !NETSTANDARD2_1 || NET5_0
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
@@ -43,4 +43,4 @@ public override WebSocketBuilder SetRequestHeader(string headerName, string head
     }
 }
 
-#endif // !NETSTANDARD2_1
+#endif // !NETSTANDARD2_1 || NET5_0