kubectl: Fix in-cluster config not loaded on flags

tchap · tchap · commit a84178bc7626 · 2025-05-30T13:47:56.000+02:00
In-cluster config is now being skipped when certain command line flags
are specified, like --request-timeout. This is now fixed and in-cluster
config is loaded even when such a flag is specified.
diff --git a/staging/src/k8s.io/client-go/tools/clientcmd/merged_client_builder.go b/staging/src/k8s.io/client-go/tools/clientcmd/merged_client_builder.go
@@ -36,8 +36,9 @@ type DeferredLoadingClientConfig struct {
 	overrides      *ConfigOverrides
 	fallbackReader io.Reader
 
-	clientConfig ClientConfig
-	loadingLock  sync.Mutex
+	clientConfig            ClientConfig
+	clientConfigNoOverrides ClientConfig
+	loadingLock             sync.Mutex
 
 	// provided for testing
 	icc InClusterConfig
@@ -59,16 +60,16 @@ func NewInteractiveDeferredLoadingClientConfig(loader ClientConfigLoader, overri
 	return &DeferredLoadingClientConfig{loader: loader, overrides: overrides, icc: &inClusterClientConfig{overrides: overrides}, fallbackReader: fallbackReader}
 }
 
-func (config *DeferredLoadingClientConfig) createClientConfig() (ClientConfig, error) {
+func (config *DeferredLoadingClientConfig) createClientConfig() (ClientConfig, ClientConfig, error) {
 	config.loadingLock.Lock()
 	defer config.loadingLock.Unlock()
 
-	if config.clientConfig != nil {
-		return config.clientConfig, nil
+	if config.clientConfig != nil && config.clientConfigNoOverrides != nil {
+		return config.clientConfig, config.clientConfigNoOverrides, nil
 	}
 	mergedConfig, err := config.loader.Load()
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	var currentContext string
@@ -80,11 +81,12 @@ func (config *DeferredLoadingClientConfig) createClientConfig() (ClientConfig, e
 	} else {
 		config.clientConfig = NewNonInteractiveClientConfig(*mergedConfig, currentContext, config.overrides, config.loader)
 	}
-	return config.clientConfig, nil
+	config.clientConfigNoOverrides = NewNonInteractiveClientConfig(*mergedConfig, "", nil, config.loader)
+	return config.clientConfig, config.clientConfigNoOverrides, nil
 }
 
 func (config *DeferredLoadingClientConfig) RawConfig() (clientcmdapi.Config, error) {
-	mergedConfig, err := config.createClientConfig()
+	mergedConfig, _, err := config.createClientConfig()
 	if err != nil {
 		return clientcmdapi.Config{}, err
 	}
@@ -94,7 +96,7 @@ func (config *DeferredLoadingClientConfig) RawConfig() (clientcmdapi.Config, err
 
 // ClientConfig implements ClientConfig
 func (config *DeferredLoadingClientConfig) ClientConfig() (*restclient.Config, error) {
-	mergedClientConfig, err := config.createClientConfig()
+	mergedClientConfig, mergedClientConfigNoOverrides, err := config.createClientConfig()
 	if err != nil {
 		return nil, err
 	}
@@ -109,9 +111,12 @@ func (config *DeferredLoadingClientConfig) ClientConfig() (*restclient.Config, e
 			return nil, err
 		}
 	case mergedConfig != nil:
-		// the configuration is valid, but if this is equal to the defaults we should try
-		// in-cluster configuration
-		if !config.loader.IsDefaultConfig(mergedConfig) {
+		mergedConfigNoOverrides, err := mergedClientConfigNoOverrides.ClientConfig()
+		if err != nil {
+			return mergedConfig, nil
+		}
+
+		if mergedConfigNoOverrides != nil && !config.loader.IsDefaultConfig(mergedConfigNoOverrides) {
 			return mergedConfig, nil
 		}
 	}
@@ -128,7 +133,7 @@ func (config *DeferredLoadingClientConfig) ClientConfig() (*restclient.Config, e
 
 // Namespace implements KubeConfig
 func (config *DeferredLoadingClientConfig) Namespace() (string, bool, error) {
-	mergedKubeConfig, err := config.createClientConfig()
+	mergedKubeConfig, _, err := config.createClientConfig()
 	if err != nil {
 		return "", false, err
 	}
diff --git a/staging/src/k8s.io/client-go/tools/clientcmd/merged_client_builder_test.go b/staging/src/k8s.io/client-go/tools/clientcmd/merged_client_builder_test.go
@@ -17,9 +17,12 @@ limitations under the License.
 package clientcmd
 
 import (
+	"errors"
 	"fmt"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
+
 	restclient "k8s.io/client-go/rest"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 )
@@ -195,17 +198,23 @@ func TestInClusterConfig(t *testing.T) {
 	}
 
 	for name, test := range testCases {
-		c := &DeferredLoadingClientConfig{icc: test.icc}
-		c.loader = &ClientConfigLoadingRules{DefaultClientConfig: test.defaultConfig}
-		c.clientConfig = test.clientConfig
-
-		cfg, err := c.ClientConfig()
-		if test.icc.called != test.checkedICC {
-			t.Errorf("%s: unexpected in-cluster-config call %t", name, test.icc.called)
-		}
-		if err != test.err || cfg != test.result {
-			t.Errorf("%s: unexpected result: %v %#v", name, err, cfg)
-		}
+		t.Run(name, func(t *testing.T) {
+			c := &DeferredLoadingClientConfig{icc: test.icc}
+			c.loader = &ClientConfigLoadingRules{DefaultClientConfig: test.defaultConfig}
+			c.clientConfig = test.clientConfig
+			c.clientConfigNoOverrides = test.clientConfig
+
+			cfg, err := c.ClientConfig()
+			if test.icc.called != test.checkedICC {
+				t.Errorf("Unexpected in-cluster-config call %t", test.icc.called)
+			}
+			if !errors.Is(err, test.err) {
+				t.Errorf("Unexpected error: %v", err)
+			}
+			if !cmp.Equal(cfg, test.result) {
+				t.Errorf("Unexpected result:\n%s", cmp.Diff(test.result, cfg))
+			}
+		})
 	}
 }
 
@@ -328,12 +337,13 @@ func TestInClusterConfigNamespace(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			c := &DeferredLoadingClientConfig{icc: test.icc, overrides: test.overrides}
 			c.clientConfig = test.clientConfig
+			c.clientConfigNoOverrides = test.clientConfig
 
 			ns, overridden, err := c.Namespace()
 			if test.icc.called != test.checkedICC {
 				t.Errorf("%s: unexpected in-cluster-config call %t", name, test.icc.called)
 			}
-			if err != test.err || ns != test.result || overridden != test.overridden {
+			if !errors.Is(err, test.err) || ns != test.result || overridden != test.overridden {
 				t.Errorf("%s: unexpected result: %v %s %t", name, err, ns, overridden)
 			}
 		})
