introduce go client style config creating functions

src/KubernetesClientConfiguration.ConfigFile.cs

@@ -0,0 +1,202 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Security.Cryptography.X509Certificates;
+using k8s.Exceptions;
+using k8s.KubeConfigModels;
+using YamlDotNet.Serialization;
+
+namespace k8s
+{
+    public partial class KubernetesClientConfiguration
+    {
+        /// <summary>
+        /// Gets CurrentContext
+        /// </summary>
+        public string CurrentContext { get; private set; }
+
+        /// <summary>
+        /// kubeconfig Default Location
+        /// </summary>
+        private static readonly string KubeConfigDefaultLocation =
+            RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
+                ? Path.Combine(Environment.GetEnvironmentVariable("USERPROFILE"), @".kube\config")
+                : Path.Combine(Environment.GetEnvironmentVariable("HOME"), ".kube/config");
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="KubernetesClientConfiguration"/> class.
+        /// </summary>
+        /// <param name="kubeconfig">kubeconfig file info</param>
+        /// <param name="currentContext">Context to use from kube config</param>
+        public KubernetesClientConfiguration(FileInfo kubeconfig = null, string currentContext = null)
+        {
+            var k8SConfig = LoadKubeConfig(kubeconfig ?? new FileInfo(KubeConfigDefaultLocation));
+            this.Initialize(k8SConfig, currentContext);
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="KubernetesClientConfiguration"/> from config file
+        /// </summary>
+        /// <param name="masterUrl">kube api server endpoint</param>
+        /// <param name="kubeconfigPath">kubeconfig filepath</param>
+        /// <returns></returns>
+        public static KubernetesClientConfiguration BuildConfigFromConfigFile(string masterUrl = null, string kubeconfigPath = null)
+        {
+            var k8SConfig = LoadKubeConfig(new FileInfo(kubeconfigPath ?? KubeConfigDefaultLocation));
+            var k8SConfiguration = new KubernetesClientConfiguration();
+            k8SConfiguration.Initialize(k8SConfig);
+
+            if (!string.IsNullOrWhiteSpace(masterUrl))
+            {
+                k8SConfiguration.Host = masterUrl;
+            }
+            return k8SConfiguration;
+        }
+
+        /// <summary>
+        /// Validates and Intializes Client Configuration
+        /// </summary>
+        /// <param name="k8SConfig">Kubernetes Configuration</param>
+        /// <param name="currentContext">Current Context</param>
+        private void Initialize(K8SConfiguration k8SConfig, string currentContext = null)
+        {
+            if (k8SConfig.Contexts == null)
+            {
+                throw new KubeConfigException("No contexts found in kubeconfig");
+            }
+
+            if (k8SConfig.Clusters == null)
+            {
+                throw new KubeConfigException($"No clusters found in kubeconfig");
+            }
+
+            if (k8SConfig.Users == null)
+            {
+                throw new KubeConfigException($"No users found in kubeconfig");
+            }
+
+            // current context
+            currentContext = currentContext ?? k8SConfig.CurrentContext;
+            Context activeContext =
+                k8SConfig.Contexts.FirstOrDefault(
+                    c => c.Name.Equals(currentContext, StringComparison.OrdinalIgnoreCase));
+            if (activeContext == null)
+            {
+                throw new KubeConfigException($"CurrentContext: {currentContext} not found in contexts in kubeconfig");
+            }
+
+            this.CurrentContext = activeContext.Name;
+
+            // cluster
+            var clusterDetails =
+                k8SConfig.Clusters.FirstOrDefault(c => c.Name.Equals(activeContext.ContextDetails.Cluster,
+                    StringComparison.OrdinalIgnoreCase));
+            if (clusterDetails?.ClusterEndpoint == null)
+            {
+                throw new KubeConfigException($"Cluster not found for context {activeContext} in kubeconfig");
+            }
+
+            if (string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.Server))
+            {
+                throw new KubeConfigException($"Server not found for current-context {activeContext} in kubeconfig");
+            }
+
+            if (!clusterDetails.ClusterEndpoint.SkipTlsVerify &&
+                string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.CertificateAuthorityData) &&
+                string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.CertificateAuthority))
+            {
+                throw new KubeConfigException(
+                    $"neither certificate-authority-data nor certificate-authority not found for current-context :{activeContext} in kubeconfig");
+            }
+
+            this.Host = clusterDetails.ClusterEndpoint.Server;
+            if (!string.IsNullOrEmpty(clusterDetails.ClusterEndpoint.CertificateAuthorityData))
+            {
+                string data = clusterDetails.ClusterEndpoint.CertificateAuthorityData;
+                this.SslCaCert = new X509Certificate2(System.Text.Encoding.UTF8.GetBytes(Utils.Base64Decode(data)));
+            }
+            else if (!string.IsNullOrEmpty(clusterDetails.ClusterEndpoint.CertificateAuthority))
+            {
+                this.SslCaCert = new X509Certificate2(clusterDetails.ClusterEndpoint.CertificateAuthority);
+            }
+            this.SkipTlsVerify = clusterDetails.ClusterEndpoint.SkipTlsVerify;
+
+            // user
+            this.SetUserDetails(k8SConfig, activeContext);
+        }
+
+        private void SetUserDetails(K8SConfiguration k8SConfig, Context activeContext)
+        {
+            var userDetails = k8SConfig.Users.FirstOrDefault(c => c.Name.Equals(activeContext.ContextDetails.User,
+                StringComparison.OrdinalIgnoreCase));
+
+            if (userDetails == null)
+            {
+                throw new KubeConfigException("User not found for context {activeContext.Name} in kubeconfig");
+            }
+
+            if (userDetails.UserCredentials == null)
+            {
+                throw new KubeConfigException($"User credentials not found for user: {userDetails.Name} in kubeconfig");
+            }
+
+            var userCredentialsFound = false;
+
+            // Basic and bearer tokens are mutually exclusive
+            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.Token))
+            {
+                this.AccessToken = userDetails.UserCredentials.Token;
+                userCredentialsFound = true;
+            }
+            else if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.UserName) &&
+                     !string.IsNullOrWhiteSpace(userDetails.UserCredentials.Password))
+            {
+                this.Username = userDetails.UserCredentials.UserName;
+                this.Password = userDetails.UserCredentials.Password;
+                userCredentialsFound = true;
+            }
+
+            // Token and cert based auth can co-exist
+            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientCertificateData) &&
+                !string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientKeyData))
+            {
+                this.ClientCertificateData = userDetails.UserCredentials.ClientCertificateData;
+                this.ClientCertificateKey = userDetails.UserCredentials.ClientKeyData;
+                userCredentialsFound = true;
+            }
+
+            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientCertificate) &&
+                !string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientKey))
+            {
+                this.ClientCertificate = userDetails.UserCredentials.ClientCertificate;
+                this.ClientKey = userDetails.UserCredentials.ClientKey;
+                userCredentialsFound = true;
+            }
+
+            if (!userCredentialsFound)
+            {
+                throw new KubeConfigException(
+                    $"User: {userDetails.Name} does not have appropriate auth credentials in kubeconfig");
+            }
+        }
+
+        /// <summary>
+        /// Loads Kube Config
+        /// </summary>
+        /// <param name="config">Kube config file contents</param>
+        /// <returns>Instance of the <see cref="K8SConfiguration"/> class</returns>
+        private static K8SConfiguration LoadKubeConfig(FileInfo kubeconfig)
+        {
+            if (!kubeconfig.Exists)
+            {
+                throw new KubeConfigException($"kubeconfig file not found at {kubeconfig.FullName}");
+            }
+            var kubeconfigContent = File.ReadAllText(kubeconfig.FullName);
+
+            var deserializeBuilder = new DeserializerBuilder();
+            var deserializer = deserializeBuilder.Build();
+            return deserializer.Deserialize<K8SConfiguration>(kubeconfigContent);
+        }
+    }
+}

src/KubernetesClientConfiguration.InCluster.cs

@@ -0,0 +1,35 @@
+using System;
+using System.IO;
+using System.Security.Cryptography.X509Certificates;
+using k8s.Exceptions;
+
+namespace k8s
+{
+    public partial class KubernetesClientConfiguration
+    {
+        private const string ServiceAccountTokenKey = "token";
+        private const string ServiceAccountRootCAKey = "ca.crt";
+
+        public static KubernetesClientConfiguration InClusterConfig()
+        {
+            var host = Environment.GetEnvironmentVariable("KUBERNETES_SERVICE_HOST");
+            var port = Environment.GetEnvironmentVariable("KUBERNETES_SERVICE_PORT");
+
+            if (string.IsNullOrWhiteSpace(host) || string.IsNullOrWhiteSpace(port))
+            {
+                throw new KubeConfigException(
+                    "unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined");
+            }
+
+            var token = File.ReadAllText("/var/run/secrets/kubernetes.io/serviceaccount/" + ServiceAccountTokenKey);
+            var rootCAFile = "/var/run/secrets/kubernetes.io/serviceaccount/" + ServiceAccountRootCAKey;
+
+            return new KubernetesClientConfiguration
+            {
+                Host = new UriBuilder("https", host, Convert.ToInt32(port)).ToString(),
+                AccessToken = token,
+                SslCaCert = Utils.LoadPemFileCert(rootCAFile)
+            };
+        }
+    }
+}

src/KubernetesClientConfiguration.cs

@@ -12,31 +12,13 @@ namespace k8s
     /// <summary>
     /// Represents a set of kubernetes client configuration settings
     /// </summary>
-    public class KubernetesClientConfiguration
+    public partial class KubernetesClientConfiguration
     {
-        /// <summary>
+        private KubernetesClientConfiguration()
-        /// Initializes a new instance of the <see cref="KubernetesClientConfiguration"/> class.
-        /// </summary>
-        /// <param name="kubeconfig">kubeconfig file info</param>
-        /// <param name="currentContext">Context to use from kube config</param>
-        public KubernetesClientConfiguration(FileInfo kubeconfig = null, string currentContext = null)
         {
-            var k8SConfig = this.LoadKubeConfig(kubeconfig ?? new FileInfo(KubeConfigDefaultLocation));
+            
-            this.Initialize(k8SConfig, currentContext);
         }
 
-        /// <summary>
-        /// kubeconfig Default Location
-        /// </summary>
-        private static readonly string KubeConfigDefaultLocation = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ?
-            Path.Combine(Environment.GetEnvironmentVariable("USERPROFILE"), @".kube\config") :
-            Path.Combine(Environment.GetEnvironmentVariable("HOME"), ".kube/config");
-
-        /// <summary>
-        /// Gets CurrentContext
-        /// </summary>
-        public string CurrentContext { get; private set; }
-
         /// <summary>
         /// Gets Host
         /// </summary>
@@ -95,142 +77,5 @@ namespace k8s
         /// </summary>
         /// <value>The access token.</value>
         public string AccessToken { get; set; }
-
-        /// <summary>
-        /// Validates and Intializes Client Configuration
-        /// </summary>
-        /// <param name="k8SConfig">Kubernetes Configuration</param>
-        /// <param name="currentContext">Current Context</param>
-        private void Initialize(K8SConfiguration k8SConfig, string currentContext = null)
-        {
-            if (k8SConfig.Contexts == null)
-            {
-                throw new KubeConfigException("No contexts found in kubeconfig");
-            }
-
-            if (k8SConfig.Clusters == null)
-            {
-                throw new KubeConfigException($"No clusters found in kubeconfig");
-            }
-            
-            if (k8SConfig.Users == null)
-            {
-                throw new KubeConfigException($"No users found in kubeconfig");
-            }
-
-            // current context
-            currentContext = currentContext ?? k8SConfig.CurrentContext;
-            Context activeContext = k8SConfig.Contexts.FirstOrDefault(c => c.Name.Equals(currentContext, StringComparison.OrdinalIgnoreCase));
-            if (activeContext == null)
-            {
-                throw new KubeConfigException($"CurrentContext: {currentContext} not found in contexts in kubeconfig");
-            }
-
-            this.CurrentContext = activeContext.Name;
-
-            // cluster
-            var clusterDetails  = k8SConfig.Clusters.FirstOrDefault(c => c.Name.Equals(activeContext.ContextDetails.Cluster, StringComparison.OrdinalIgnoreCase));
-            if (clusterDetails?.ClusterEndpoint == null)
-            {
-                throw new KubeConfigException($"Cluster not found for context {activeContext} in kubeconfig");
-            }
-
-            if (string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.Server))
-            {
-                throw new KubeConfigException($"Server not found for current-context {activeContext} in kubeconfig");
-            }
-
-            if (!clusterDetails.ClusterEndpoint.SkipTlsVerify &&
-                string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.CertificateAuthorityData) &&
-                string.IsNullOrWhiteSpace(clusterDetails.ClusterEndpoint.CertificateAuthority))
-            {
-                throw new KubeConfigException($"neither certificate-authority-data nor certificate-authority not found for current-context :{activeContext} in kubeconfig");
-            }
-
-            this.Host = clusterDetails.ClusterEndpoint.Server;
-            if (!string.IsNullOrEmpty(clusterDetails.ClusterEndpoint.CertificateAuthorityData))
-            {
-                string data = clusterDetails.ClusterEndpoint.CertificateAuthorityData;
-                this.SslCaCert = new X509Certificate2(System.Text.Encoding.UTF8.GetBytes(Utils.Base64Decode(data)));
-            }
-            else if (!string.IsNullOrEmpty(clusterDetails.ClusterEndpoint.CertificateAuthority))
-            {
-                this.SslCaCert = new X509Certificate2(clusterDetails.ClusterEndpoint.CertificateAuthority);
-            }
-            this.SkipTlsVerify = clusterDetails.ClusterEndpoint.SkipTlsVerify;
-
-            // user
-            this.SetUserDetails(k8SConfig, activeContext);
-        }
-
-        private void SetUserDetails(K8SConfiguration k8SConfig, Context activeContext)
-        {
-            var userDetails = k8SConfig.Users.FirstOrDefault(c => c.Name.Equals(activeContext.ContextDetails.User, StringComparison.OrdinalIgnoreCase));
-
-            if (userDetails == null)
-            {
-                throw new KubeConfigException("User not found for context {activeContext.Name} in kubeconfig");
-            }
-
-            if (userDetails.UserCredentials == null)
-            {
-                throw new KubeConfigException($"User credentials not found for user: {userDetails.Name} in kubeconfig");
-            }
-
-            var userCredentialsFound = false;
-
-            // Basic and bearer tokens are mutually exclusive
-            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.Token))
-            {
-                this.AccessToken = userDetails.UserCredentials.Token;
-                userCredentialsFound = true;
-            }
-            else if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.UserName) &&
-                        !string.IsNullOrWhiteSpace(userDetails.UserCredentials.Password))
-            {
-                this.Username = userDetails.UserCredentials.UserName;
-                this.Password = userDetails.UserCredentials.Password;
-                userCredentialsFound = true;
-            }
-
-            // Token and cert based auth can co-exist
-            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientCertificateData) &&
-                        !string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientKeyData))
-            {
-                this.ClientCertificateData = userDetails.UserCredentials.ClientCertificateData;
-                this.ClientCertificateKey = userDetails.UserCredentials.ClientKeyData;
-                userCredentialsFound = true;
-            }
-
-            if (!string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientCertificate) &&
-                !string.IsNullOrWhiteSpace(userDetails.UserCredentials.ClientKey)) {
-                this.ClientCertificate = userDetails.UserCredentials.ClientCertificate;
-                this.ClientKey = userDetails.UserCredentials.ClientKey;
-                userCredentialsFound = true;
-            }
-
-            if (!userCredentialsFound)
-            {
-                throw new KubeConfigException($"User: {userDetails.Name} does not have appropriate auth credentials in kubeconfig");
-            }
-        }
-
-        /// <summary>
-        /// Loads Kube Config
-        /// </summary>
-        /// <param name="config">Kube config file contents</param>
-        /// <returns>Instance of the <see cref="K8SConfiguration"/> class</returns>
-        private K8SConfiguration LoadKubeConfig(FileInfo kubeconfig)
-        {
-            if (!kubeconfig.Exists)
-            {
-                throw new KubeConfigException($"kubeconfig file not found at {kubeconfig.FullName}");
-            }
-            var kubeconfigContent = File.ReadAllText(kubeconfig.FullName);
-
-            var deserializeBuilder = new DeserializerBuilder();
-            var deserializer = deserializeBuilder.Build();
-            return deserializer.Deserialize<K8SConfiguration>(kubeconfigContent);
-        }
     }
 }

src/Utils.cs

@@ -35,7 +35,23 @@ namespace k8s
         }
 
         /// <summary>
-        ///     Generates pfx from client configuration
+        /// Load pem encoded cert file
+        /// </summary>
+        /// <param name="file">Path to pem encoded cert file</param>
+        /// <returns>x509 instance.</returns>
+        public static X509Certificate2 LoadPemFileCert(string file)
+        {
+            var certdata = File.ReadAllText(file)
+                .Replace("-----BEGIN CERTIFICATE-----", "")
+                .Replace("-----END CERTIFICATE-----", "")
+                .Replace("\r", "")
+                .Replace("\n", "");
+
+            return new X509Certificate2(Convert.FromBase64String(certdata));
+        }
+
+        /// <summary>
+        /// Generates pfx from client configuration
         /// </summary>
         /// <param name="config">Kuberentes Client Configuration</param>
         /// <returns>Generated Pfx Path</returns>
@@ -98,4 +114,4 @@ namespace k8s
             }
         }
     }
-}
+}