feat: Show a friendly message when not connected into any cluster

internal/resource/errors.go

@@ -0,0 +1,32 @@
+package resource
+
+import (
+	"fmt"
+	"strings"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+)
+
+// wrapKubernetesError takes an error returned from a Kubernetes API call and returns a more user-friendly error message if it recognizes the error type If err is nil, it returns nil. If the error is not recognized, it returns the original error.
+func wrapKubernetesError(err error) error {
+	if err == nil {
+		return nil
+	}
+
+	if errors.IsUnauthorized(err) {
+		return fmt.Errorf("you are not authorized to access the cluster. Please check if you are logged in and your credentials are valid: %w", err)
+	}
+
+	if errors.IsForbidden(err) {
+		return fmt.Errorf("you do not have permission to perform this action in the cluster: %w", err)
+	}
+
+	errStr := strings.ToLower(err.Error())
+	if strings.Contains(errStr, "no configuration has been provided") ||
+		strings.Contains(errStr, "unable to load in-cluster configuration") ||
+		strings.Contains(errStr, "couldn't find kubeconfig file") {
+		return fmt.Errorf("no Kubernetes configuration found. Please ensure you have a valid kubeconfig file or that your KUBECONFIG environment variable is set: %w", err)
+	}
+
+	return err
+}

internal/resource/resource_searcher.go

@@ -35,17 +35,17 @@ func NewResourceSearcher(resourceType string) (*Searcher, error) {
 	configOverrides := &clientcmd.ConfigOverrides{}
 	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, configOverrides).ClientConfig()
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes config: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes config: %w", err))
 	}
 
 	clientset, err := kubernetes.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes clientset: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes clientset: %w", err))
 	}
 
 	dynamicClient, err := dynamic.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating dynamic client: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating dynamic client: %w", err))
 	}
 
 	kubeGet, err := gokubeget.NewKubeGet(config)
@@ -70,17 +70,17 @@ func NewGenericResourceSearcher(apiVersion, kind string) (*Searcher, error) {
 	configOverrides := &clientcmd.ConfigOverrides{}
 	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, configOverrides).ClientConfig()
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes config: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes config: %w", err))
 	}
 
 	clientset, err := kubernetes.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes clientset: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes clientset: %w", err))
 	}
 
 	dynamicClient, err := dynamic.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating dynamic client: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating dynamic client: %w", err))
 	}
 
 	kubeGet, err := gokubeget.NewKubeGet(config)
@@ -105,17 +105,17 @@ func NewAutoDiscoveryResourceSearcher(kind string) (*Searcher, error) {
 	configOverrides := &clientcmd.ConfigOverrides{}
 	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, configOverrides).ClientConfig()
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes config: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes config: %w", err))
 	}
 
 	clientset, err := kubernetes.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating Kubernetes clientset: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating Kubernetes clientset: %w", err))
 	}
 
 	dynamicClient, err := dynamic.NewForConfig(config)
 	if err != nil {
-		return nil, fmt.Errorf("error creating dynamic client: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error creating dynamic client: %w", err))
 	}
 
 	kubeGet, err := gokubeget.NewKubeGet(config)
@@ -137,7 +137,7 @@ func NewAutoDiscoveryResourceSearcher(kind string) (*Searcher, error) {
 func (s *Searcher) SearchWithoutNamespace(pattern string) ([]Occurrence, error) {
 	namespace, err := s.getDefaultNamespace()
 	if err != nil {
-		return nil, fmt.Errorf("error getting default namespace: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error getting default namespace: %w", err))
 	}
 	return s.Search(namespace, pattern)
 }
@@ -150,7 +150,7 @@ func (s *Searcher) Search(namespace, pattern string) ([]Occurrence, error) {
 
 	resources, err := s.getGenericResourceNames(namespace)
 	if err != nil {
-		return nil, fmt.Errorf("error getting resources: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error getting resources: %w", err))
 	}
 
 	var occurrences []Occurrence
@@ -170,7 +170,7 @@ func (s *Searcher) SearchAllNamespaces(pattern string) ([]Occurrence, error) {
 
 	namespaces, err := s.getAllNamespaces()
 	if err != nil {
-		return nil, fmt.Errorf("error getting namespaces: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error getting namespaces: %w", err))
 	}
 
 	var allOccurrences []Occurrence
@@ -238,7 +238,7 @@ func (s *Searcher) getAllNamespaces() ([]string, error) {
 
 	namespaces, err := s.clientset.CoreV1().Namespaces().List(context.Background(), metav1.ListOptions{})
 	if err != nil {
-		return nil, fmt.Errorf("error listing namespaces: %v", err)
+		return nil, wrapKubernetesError(fmt.Errorf("error listing namespaces: %w", err))
 	}
 
 	var namespaceNames []string
@@ -302,7 +302,7 @@ func (s *Searcher) getGenericResourceNames(namespace string) ([]string, error) {
 		}
 	}
 
-	return nil, fmt.Errorf("error getting %s resources: %v", s.kind, err)
+	return nil, wrapKubernetesError(fmt.Errorf("error getting %s resources: %w", s.kind, err))
 }
 
 // getGenericResourceYAML gets YAML for generic resources.
@@ -362,7 +362,7 @@ func (s *Searcher) getGenericResourceYAML(namespace, name string) (string, error
 		}
 	}
 
-	return "", fmt.Errorf("error getting %s resources: %v", s.kind, err)
+	return "", wrapKubernetesError(fmt.Errorf("error getting %s resources: %w", s.kind, err))
 }
 
 // objectToYAML converts a runtime.Object to YAML string.
@@ -383,7 +383,7 @@ func (s *Searcher) discoverAPIVersionAndKind() (string, string, string, error) {
 
 	apiGroups, err := s.clientset.Discovery().ServerGroups()
 	if err != nil {
-		return "", "", "", fmt.Errorf("error getting API groups: %v", err)
+		return "", "", "", wrapKubernetesError(fmt.Errorf("error getting API groups: %w", err))
 	}
 
 	for _, group := range apiGroups.Groups {

internal/resource/resource_searcher_test.go

@@ -1,10 +1,13 @@
 package resource
 
 import (
+	"fmt"
 	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/client-go/kubernetes/fake"
 )
 
@@ -365,3 +368,63 @@ func TestSearcher_APIVersionAndKindPrecedence(t *testing.T) {
 	assert.Error(t, err)
 	assert.Contains(t, err.Error(), "kubeGet client not available")
 }
+
+func TestWrapKubernetesError(t *testing.T) {
+	assert.NoError(t, wrapKubernetesError(nil))
+
+	t.Run("unauthorized error", func(t *testing.T) {
+		origErr := errors.NewUnauthorized("unauthorized")
+		wrapped := wrapKubernetesError(origErr)
+		assert.Error(t, wrapped)
+		assert.Contains(t, wrapped.Error(), "you are not authorized to access the cluster")
+		assert.ErrorIs(t, wrapped, origErr)
+	})
+
+	t.Run("forbidden error", func(t *testing.T) {
+		origErr := errors.NewForbidden(schema.GroupResource{}, "name", fmt.Errorf("forbidden"))
+		wrapped := wrapKubernetesError(origErr)
+		assert.Error(t, wrapped)
+		assert.Contains(t, wrapped.Error(), "you do not have permission to perform this action")
+		assert.ErrorIs(t, wrapped, origErr)
+	})
+
+	t.Run("configuration errors", func(t *testing.T) {
+		configErrs := []string{
+			"no configuration has been provided",
+			"unable to load in-cluster configuration",
+			"Couldn't find kubeconfig file",
+		}
+
+		for _, msg := range configErrs {
+			t.Run(msg, func(t *testing.T) {
+				origErr := fmt.Errorf("%s", msg)
+				wrapped := wrapKubernetesError(origErr)
+				assert.Error(t, wrapped)
+				assert.Contains(t, wrapped.Error(), "no Kubernetes configuration found")
+				assert.ErrorIs(t, wrapped, origErr)
+			})
+		}
+	})
+
+	t.Run("invalid configuration substring is not rewritten", func(t *testing.T) {
+		origErr := fmt.Errorf("parser failed: invalid configuration in application payload")
+		wrapped := wrapKubernetesError(origErr)
+		assert.Equal(t, origErr, wrapped)
+	})
+
+	t.Run("context preservation", func(t *testing.T) {
+		origErr := errors.NewUnauthorized("unauthorized")
+		contextErr := fmt.Errorf("outer context: %w", origErr)
+		wrapped := wrapKubernetesError(contextErr)
+		assert.Error(t, wrapped)
+		assert.Contains(t, wrapped.Error(), "outer context")
+		assert.Contains(t, wrapped.Error(), "you are not authorized to access the cluster")
+		assert.ErrorIs(t, wrapped, origErr)
+	})
+
+	t.Run("unknown error", func(t *testing.T) {
+		origErr := fmt.Errorf("some random error")
+		wrapped := wrapKubernetesError(origErr)
+		assert.Equal(t, origErr, wrapped)
+	})
+}