watcher handler will auto patch to all ctor path

src/Kubernetes.ConfigInit.cs

@@ -1,17 +1,15 @@
 using k8s.Models;
-
-namespace k8s
-{
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.Net.Http;
 using System.Net.Security;
 using System.Security.Cryptography.X509Certificates;
-    using System.Threading.Tasks;
 using k8s.Exceptions;
 using Microsoft.Rest;
 
-    public partial class Kubernetes : ServiceClient<Kubernetes>, IKubernetes
+namespace k8s
+{
+    public partial class Kubernetes
     {
         /// <summary>
         ///     Initializes a new instance of the <see cref="Kubernetes" /> class.
@@ -19,20 +17,20 @@ namespace k8s
         /// <param name='config'>
         ///     Optional. The delegating handlers to add to the http client pipeline.
         /// </param>
-        public Kubernetes(KubernetesClientConfiguration config)
+        /// <param name="handlers">
+        ///     Optional. The delegating handlers to add to the http client pipeline.
+        /// </param>
+        public Kubernetes(KubernetesClientConfiguration config, params DelegatingHandler[] handlers) : this(handlers)
         {
-            this.Initialize();
-
-            this.CaCert = config.SslCaCert;
-            this.BaseUri = new Uri(config.Host);
-
-            var handler = new HttpClientHandler();
+            CaCert = config.SslCaCert;
+            BaseUri = new Uri(config.Host);
 
             if (BaseUri.Scheme == "https")
             {
                 if (config.SkipTlsVerify)
                 {
-                    handler.ServerCertificateCustomValidationCallback = (sender, certificate, chain, sslPolicyErrors) => true;
+                    HttpClientHandler.ServerCertificateCustomValidationCallback =
+                        (sender, certificate, chain, sslPolicyErrors) => true;
                 }
                 else
                 {
@@ -41,18 +39,44 @@ namespace k8s
                         throw new KubeConfigException("a CA must be set when SkipTlsVerify === false");
                     }
 
-                    handler.ServerCertificateCustomValidationCallback = CertificateValidationCallBack;
+                    HttpClientHandler.ServerCertificateCustomValidationCallback = CertificateValidationCallBack;
                 }
             }
 
             // set credentails for the kubernernet client
-            this.SetCredentials(config, handler);
-            this.InitializeHttpClient(handler, new DelegatingHandler[]{new WatcherDelegatingHandler()});
+            SetCredentials(config, HttpClientHandler);
+        }
 
+        private X509Certificate2 CaCert { get; }
+
+        partial void CustomInitialize()
+        {
+            AppendDelegatingHandler<WatcherDelegatingHandler>();
             DeserializationSettings.Converters.Add(new V1Status.V1StatusObjectViewConverter());
         }
 
-        private X509Certificate2 CaCert { get; set; }
+        private void AppendDelegatingHandler<T>() where T : DelegatingHandler, new()
+        {
+            var cur = FirstMessageHandler as DelegatingHandler;
+
+            while (cur != null)
+            {
+                var next = cur.InnerHandler as DelegatingHandler;
+
+                if (next == null)
+                {
+                    // last one
+                    // append watcher handler between to last handler
+                    cur.InnerHandler = new T
+                    {
+                        InnerHandler = cur.InnerHandler
+                    };
+                    break;
+                }
+
+                cur = next;
+            }
+        }
 
         /// <summary>
         ///     Set credentials for the Client
@@ -114,16 +138,13 @@ namespace k8s
                 chain.ChainPolicy.RevocationMode = X509RevocationMode.NoCheck;
 
                 // add all your extra certificate chain
-                chain.ChainPolicy.ExtraStore.Add(this.CaCert);
+                chain.ChainPolicy.ExtraStore.Add(CaCert);
                 chain.ChainPolicy.VerificationFlags = X509VerificationFlags.AllowUnknownCertificateAuthority;
                 var isValid = chain.Build((X509Certificate2) certificate);
                 return isValid;
             }
-            else
-            {
             // In all other cases, return false.
             return false;
         }
     }
 }
-}