test(config): add new test case to increase the test coverage of Derived Config (167)

Add new unit tests to check the values in Derived config
---
Rely on kubeconfig in staticConfig instead of a separate but equal one

pkg/kubernetes/configuration.go

@@ -24,8 +24,8 @@ var InClusterConfig = func() (*rest.Config, error) {
 func resolveKubernetesConfigurations(kubernetes *Manager) error {
 	// Always set clientCmdConfig
 	pathOptions := clientcmd.NewDefaultPathOptions()
-	if kubernetes.Kubeconfig != "" {
-		pathOptions.LoadingRules.ExplicitPath = kubernetes.Kubeconfig
+	if kubernetes.staticConfig.KubeConfig != "" {
+		pathOptions.LoadingRules.ExplicitPath = kubernetes.staticConfig.KubeConfig
 	}
 	kubernetes.clientCmdConfig = clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
 		pathOptions.LoadingRules,
@@ -46,7 +46,7 @@ func resolveKubernetesConfigurations(kubernetes *Manager) error {
 }
 
 func (m *Manager) IsInCluster() bool {
-	if m.Kubeconfig != "" {
+	if m.staticConfig.KubeConfig != "" {
 		return false
 	}
 	cfg, err := InClusterConfig()

pkg/kubernetes/configuration_test.go

@@ -2,18 +2,23 @@ package kubernetes
 
 import (
 	"errors"
-	"k8s.io/client-go/rest"
 	"os"
 	"path"
 	"runtime"
 	"strings"
 	"testing"
+
+	"k8s.io/client-go/rest"
+
+	"github.com/manusa/kubernetes-mcp-server/pkg/config"
 )
 
 func TestKubernetes_IsInCluster(t *testing.T) {
 	t.Run("with explicit kubeconfig", func(t *testing.T) {
 		m := Manager{
-			Kubeconfig: "kubeconfig",
+			staticConfig: &config.StaticConfig{
+				KubeConfig: "kubeconfig",
+			},
 		}
 		if m.IsInCluster() {
 			t.Errorf("expected not in cluster, got in cluster")
@@ -28,7 +33,9 @@ func TestKubernetes_IsInCluster(t *testing.T) {
 			InClusterConfig = originalFunction
 		}()
 		m := Manager{
-			Kubeconfig: "",
+			staticConfig: &config.StaticConfig{
+				KubeConfig: "",
+			},
 		}
 		if !m.IsInCluster() {
 			t.Errorf("expected in cluster, got not in cluster")
@@ -43,7 +50,9 @@ func TestKubernetes_IsInCluster(t *testing.T) {
 			InClusterConfig = originalFunction
 		}()
 		m := Manager{
-			Kubeconfig: "",
+			staticConfig: &config.StaticConfig{
+				KubeConfig: "",
+			},
 		}
 		if m.IsInCluster() {
 			t.Errorf("expected not in cluster, got in cluster")
@@ -58,7 +67,9 @@ func TestKubernetes_IsInCluster(t *testing.T) {
 			InClusterConfig = originalFunction
 		}()
 		m := Manager{
-			Kubeconfig: "",
+			staticConfig: &config.StaticConfig{
+				KubeConfig: "",
+			},
 		}
 		if m.IsInCluster() {
 			t.Errorf("expected not in cluster, got in cluster")
@@ -72,7 +83,9 @@ func TestKubernetes_ResolveKubernetesConfigurations_Explicit(t *testing.T) {
 			t.Skip("Skipping test on non-linux platforms")
 		}
 		tempDir := t.TempDir()
-		m := Manager{Kubeconfig: path.Join(tempDir, "config")}
+		m := Manager{staticConfig: &config.StaticConfig{
+			KubeConfig: path.Join(tempDir, "config"),
+		}}
 		err := resolveKubernetesConfigurations(&m)
 		if err == nil {
 			t.Errorf("expected error, got nil")
@@ -90,7 +103,9 @@ func TestKubernetes_ResolveKubernetesConfigurations_Explicit(t *testing.T) {
 		if err := os.WriteFile(kubeconfigPath, []byte(""), 0644); err != nil {
 			t.Fatalf("failed to create kubeconfig file: %v", err)
 		}
-		m := Manager{Kubeconfig: kubeconfigPath}
+		m := Manager{staticConfig: &config.StaticConfig{
+			KubeConfig: kubeconfigPath,
+		}}
 		err := resolveKubernetesConfigurations(&m)
 		if err == nil {
 			t.Errorf("expected error, got nil")
@@ -123,7 +138,9 @@ users:
 		if err := os.WriteFile(kubeconfigPath, []byte(kubeconfigContent), 0644); err != nil {
 			t.Fatalf("failed to create kubeconfig file: %v", err)
 		}
-		m := Manager{Kubeconfig: kubeconfigPath}
+		m := Manager{staticConfig: &config.StaticConfig{
+			KubeConfig: kubeconfigPath,
+		}}
 		err := resolveKubernetesConfigurations(&m)
 		if err != nil {
 			t.Fatalf("expected no error, got %v", err)

pkg/kubernetes/kubernetes.go

@@ -39,8 +39,6 @@ type Kubernetes struct {
 }
 
 type Manager struct {
-	// Kubeconfig path override
-	Kubeconfig              string
 	cfg                     *rest.Config
 	clientCmdConfig         clientcmd.ClientConfig
 	discoveryClient         discovery.CachedDiscoveryInterface
@@ -57,9 +55,8 @@ var ParameterCodec = runtime.NewParameterCodec(Scheme)
 
 var _ helm.Kubernetes = &Manager{}
 
-func NewManager(kubeconfig string, config *config.StaticConfig) (*Manager, error) {
+func NewManager(config *config.StaticConfig) (*Manager, error) {
 	k8s := &Manager{
-		Kubeconfig:   kubeconfig,
 		staticConfig: config,
 	}
 	if err := resolveKubernetesConfigurations(k8s); err != nil {
@@ -166,7 +163,6 @@ func (m *Manager) Derived(ctx context.Context) *Kubernetes {
 	}
 	clientCmdApiConfig.AuthInfos = make(map[string]*clientcmdapi.AuthInfo)
 	derived := &Kubernetes{manager: &Manager{
-		Kubeconfig:      m.Kubeconfig,
 		clientCmdConfig: clientcmd.NewDefaultClientConfig(clientCmdApiConfig, nil),
 		cfg:             derivedCfg,
 		staticConfig:    m.staticConfig,

pkg/kubernetes/kubernetes_test.go

@@ -0,0 +1,211 @@
+package kubernetes
+
+import (
+	"context"
+	"os"
+	"path"
+	"testing"
+
+	"github.com/manusa/kubernetes-mcp-server/pkg/config"
+)
+
+func TestManager_Derived(t *testing.T) {
+	// Create a temporary kubeconfig file for testing
+	tempDir := t.TempDir()
+	kubeconfigPath := path.Join(tempDir, "config")
+	kubeconfigContent := `
+apiVersion: v1
+kind: Config
+clusters:
+- cluster:
+    server: https://test-cluster.example.com
+  name: test-cluster
+contexts:
+- context:
+    cluster: test-cluster
+    user: test-user
+  name: test-context
+current-context: test-context
+users:
+- name: test-user
+  user:
+    username: test-username
+    password: test-password
+`
+	if err := os.WriteFile(kubeconfigPath, []byte(kubeconfigContent), 0644); err != nil {
+		t.Fatalf("failed to create kubeconfig file: %v", err)
+	}
+
+	t.Run("without authorization header returns original manager", func(t *testing.T) {
+		testStaticConfig := &config.StaticConfig{
+			KubeConfig:    kubeconfigPath,
+			DisabledTools: []string{"configuration_view"},
+			DeniedResources: []config.GroupVersionKind{
+				{Group: "apps", Version: "v1", Kind: "Deployment"},
+			},
+		}
+
+		testManager, err := NewManager(testStaticConfig)
+		if err != nil {
+			t.Fatalf("failed to create manager: %v", err)
+		}
+		defer testManager.Close()
+		ctx := context.Background()
+		derived := testManager.Derived(ctx)
+
+		if derived.manager != testManager {
+			t.Errorf("expected original manager, got different manager")
+		}
+	})
+
+	t.Run("with invalid authorization header returns original manager", func(t *testing.T) {
+		testStaticConfig := &config.StaticConfig{
+			KubeConfig:    kubeconfigPath,
+			DisabledTools: []string{"configuration_view"},
+			DeniedResources: []config.GroupVersionKind{
+				{Group: "apps", Version: "v1", Kind: "Deployment"},
+			},
+		}
+
+		testManager, err := NewManager(testStaticConfig)
+		if err != nil {
+			t.Fatalf("failed to create manager: %v", err)
+		}
+		defer testManager.Close()
+		ctx := context.WithValue(context.Background(), OAuthAuthorizationHeader, "invalid-token")
+		derived := testManager.Derived(ctx)
+
+		if derived.manager != testManager {
+			t.Errorf("expected original manager, got different manager")
+		}
+	})
+
+	t.Run("with valid bearer token creates derived manager with correct configuration", func(t *testing.T) {
+		testStaticConfig := &config.StaticConfig{
+			KubeConfig:    kubeconfigPath,
+			DisabledTools: []string{"configuration_view"},
+			DeniedResources: []config.GroupVersionKind{
+				{Group: "apps", Version: "v1", Kind: "Deployment"},
+			},
+		}
+
+		testManager, err := NewManager(testStaticConfig)
+		if err != nil {
+			t.Fatalf("failed to create manager: %v", err)
+		}
+		defer testManager.Close()
+		testBearerToken := "test-bearer-token-123"
+		ctx := context.WithValue(context.Background(), OAuthAuthorizationHeader, "Bearer "+testBearerToken)
+		derived := testManager.Derived(ctx)
+
+		if derived.manager == testManager {
+			t.Errorf("expected new derived manager, got original manager")
+		}
+
+		if derived.manager.staticConfig != testStaticConfig {
+			t.Errorf("staticConfig not properly wired to derived manager")
+		}
+
+		derivedCfg := derived.manager.cfg
+		if derivedCfg == nil {
+			t.Fatalf("derived config is nil")
+		}
+
+		originalCfg := testManager.cfg
+		if derivedCfg.Host != originalCfg.Host {
+			t.Errorf("expected Host %s, got %s", originalCfg.Host, derivedCfg.Host)
+		}
+		if derivedCfg.APIPath != originalCfg.APIPath {
+			t.Errorf("expected APIPath %s, got %s", originalCfg.APIPath, derivedCfg.APIPath)
+		}
+		if derivedCfg.QPS != originalCfg.QPS {
+			t.Errorf("expected QPS %f, got %f", originalCfg.QPS, derivedCfg.QPS)
+		}
+		if derivedCfg.Burst != originalCfg.Burst {
+			t.Errorf("expected Burst %d, got %d", originalCfg.Burst, derivedCfg.Burst)
+		}
+		if derivedCfg.Timeout != originalCfg.Timeout {
+			t.Errorf("expected Timeout %v, got %v", originalCfg.Timeout, derivedCfg.Timeout)
+		}
+
+		if derivedCfg.TLSClientConfig.Insecure != originalCfg.TLSClientConfig.Insecure {
+			t.Errorf("expected TLS Insecure %v, got %v", originalCfg.TLSClientConfig.Insecure, derivedCfg.TLSClientConfig.Insecure)
+		}
+		if derivedCfg.TLSClientConfig.ServerName != originalCfg.TLSClientConfig.ServerName {
+			t.Errorf("expected TLS ServerName %s, got %s", originalCfg.TLSClientConfig.ServerName, derivedCfg.TLSClientConfig.ServerName)
+		}
+		if derivedCfg.TLSClientConfig.CAFile != originalCfg.TLSClientConfig.CAFile {
+			t.Errorf("expected TLS CAFile %s, got %s", originalCfg.TLSClientConfig.CAFile, derivedCfg.TLSClientConfig.CAFile)
+		}
+		if string(derivedCfg.TLSClientConfig.CAData) != string(originalCfg.TLSClientConfig.CAData) {
+			t.Errorf("expected TLS CAData %s, got %s", string(originalCfg.TLSClientConfig.CAData), string(derivedCfg.TLSClientConfig.CAData))
+		}
+
+		if derivedCfg.BearerToken != testBearerToken {
+			t.Errorf("expected BearerToken %s, got %s", testBearerToken, derivedCfg.BearerToken)
+		}
+		if derivedCfg.UserAgent != CustomUserAgent {
+			t.Errorf("expected UserAgent %s, got %s", CustomUserAgent, derivedCfg.UserAgent)
+		}
+
+		// Verify that sensitive fields are NOT copied to prevent credential leakage
+		// The derived config should only use the bearer token from the Authorization header
+		// and not inherit any authentication credentials from the original kubeconfig
+		if derivedCfg.TLSClientConfig.CertFile != "" {
+			t.Errorf("expected TLS CertFile to be empty, got %s", derivedCfg.TLSClientConfig.CertFile)
+		}
+		if derivedCfg.TLSClientConfig.KeyFile != "" {
+			t.Errorf("expected TLS KeyFile to be empty, got %s", derivedCfg.TLSClientConfig.KeyFile)
+		}
+		if len(derivedCfg.TLSClientConfig.CertData) != 0 {
+			t.Errorf("expected TLS CertData to be empty, got %v", derivedCfg.TLSClientConfig.CertData)
+		}
+		if len(derivedCfg.TLSClientConfig.KeyData) != 0 {
+			t.Errorf("expected TLS KeyData to be empty, got %v", derivedCfg.TLSClientConfig.KeyData)
+		}
+
+		if derivedCfg.Username != "" {
+			t.Errorf("expected Username to be empty, got %s", derivedCfg.Username)
+		}
+		if derivedCfg.Password != "" {
+			t.Errorf("expected Password to be empty, got %s", derivedCfg.Password)
+		}
+		if derivedCfg.AuthProvider != nil {
+			t.Errorf("expected AuthProvider to be nil, got %v", derivedCfg.AuthProvider)
+		}
+		if derivedCfg.ExecProvider != nil {
+			t.Errorf("expected ExecProvider to be nil, got %v", derivedCfg.ExecProvider)
+		}
+		if derivedCfg.BearerTokenFile != "" {
+			t.Errorf("expected BearerTokenFile to be empty, got %s", derivedCfg.BearerTokenFile)
+		}
+		if derivedCfg.Impersonate.UserName != "" {
+			t.Errorf("expected Impersonate.UserName to be empty, got %s", derivedCfg.Impersonate.UserName)
+		}
+
+		// Verify that the original manager still has the sensitive data
+		if originalCfg.Username == "" && originalCfg.Password == "" {
+			t.Logf("original kubeconfig shouldn't be modified")
+		}
+
+		// Verify that the derived manager has proper clients initialized
+		if derived.manager.accessControlClientSet == nil {
+			t.Error("expected accessControlClientSet to be initialized")
+		}
+		if derived.manager.accessControlClientSet.staticConfig != testStaticConfig {
+			t.Errorf("staticConfig not properly wired to derived manager")
+		}
+		if derived.manager.discoveryClient == nil {
+			t.Error("expected discoveryClient to be initialized")
+		}
+		if derived.manager.accessControlRESTMapper == nil {
+			t.Error("expected accessControlRESTMapper to be initialized")
+		}
+		if derived.manager.accessControlRESTMapper.staticConfig != testStaticConfig {
+			t.Errorf("staticConfig not properly wired to derived manager")
+		}
+		if derived.manager.dynamicClient == nil {
+			t.Error("expected dynamicClient to be initialized")
+		}
+	})
+}

pkg/mcp/mcp.go

@@ -65,7 +65,7 @@ func NewServer(configuration Configuration) (*Server, error) {
 }
 
 func (s *Server) reloadKubernetesClient() error {
-	k, err := internalk8s.NewManager(s.configuration.StaticConfig.KubeConfig, s.configuration.StaticConfig)
+	k, err := internalk8s.NewManager(s.configuration.StaticConfig)
 	if err != nil {
 		return err
 	}