fix: Exec hangs

src/KubernetesClient/KubernetesClientConfiguration.ConfigFile.cs

@@ -6,6 +6,7 @@
 using System.Net;
 using System.Runtime.InteropServices;
 using System.Security.Cryptography.X509Certificates;
+using System.Text;
 using System.Threading.Tasks;
 
 namespace k8s
@@ -28,6 +29,11 @@ public partial class KubernetesClientConfiguration
         // For testing
         internal static string KubeConfigEnvironmentVariable { get; set; } = "KUBECONFIG";
 
+        /// <summary>
+        /// Exec process timeout in seconds
+        /// </summary>
+        public static int ExecTimeout { get; set; } = 10;
+
         /// <summary>
         ///     Initializes a new instance of the <see cref="KubernetesClientConfiguration" /> from default locations
         ///     If the KUBECONFIG environment variable is set, then that will be used.
@@ -557,19 +563,31 @@ public static ExecCredentialResponse ExecuteExternalCommand(ExternalExecution co
                 throw new KubeConfigException($"external exec failed due to: {ex.Message}");
             }
 
-            var stdout = process.StandardOutput.ReadToEnd();
-            var stderr = process.StandardError.ReadToEnd();
-            if (string.IsNullOrWhiteSpace(stderr) == false)
+            var stdOutTask = process.StandardOutput.ReadToEndAsync(); // Assumes process exits
+
+            var buffer = new char[4096];
+            var stdErrorTask = process.StandardError.ReadAsync(buffer, 0, buffer.Length); // Assumes process will continue
+
+            var result = Task.WaitAny(new Task[] { stdErrorTask, stdOutTask }, TimeSpan.FromSeconds(ExecTimeout));
+
+            if (result == -1)
             {
-                throw new KubeConfigException($"external exec failed due to: {stderr}");
+                throw new KubeConfigException("external exec failed due to timeout");
             }
+            else if (result == 0)
+            {
+                var stderrBuilder = new StringBuilder();
+                stderrBuilder.Append(buffer, 0, stdErrorTask.GetAwaiter().GetResult());
 
-            // Wait for a maximum of 5 seconds, if a response takes longer probably something went wrong...
-            process.WaitForExit(5);
+                if (stderrBuilder.Length > 0)
+                {
+                    throw new KubeConfigException($"external exec failed due to: {stderrBuilder}");
+                }
+            }
 
             try
             {
-                var responseObject = KubernetesJson.Deserialize<ExecCredentialResponse>(stdout);
+                var responseObject = KubernetesJson.Deserialize<ExecCredentialResponse>(stdOutTask.GetAwaiter().GetResult());
                 if (responseObject == null || responseObject.ApiVersion != config.ApiVersion)
                 {
                     throw new KubeConfigException(