Merge pull request #3107 from corneliusweig/w/kubeconfig-cli-go

Prepare cli-go to accept `--kubeconfig` setting

cmd/skaffold/app/cmd/runner.go

@@ -72,7 +72,7 @@ func createNewRunner(opts config.SkaffoldOptions) (runner.Runner, *latest.Skaffo
 		return nil, nil, errors.Wrap(err, "applying profiles")
 	}
 
-	kubectx.UseKubeContext(opts.KubeContext, config.Deploy.KubeContext)
+	kubectx.ConfigureKubeConfig(opts.KubeConfig, opts.KubeContext, config.Deploy.KubeContext)
 
 	if err := defaults.Set(config); err != nil {
 		return nil, nil, errors.Wrap(err, "setting default values")

pkg/skaffold/config/options.go

@@ -55,6 +55,7 @@ type SkaffoldOptions struct {
 	CacheFile          string
 	Trigger            string
 	KubeContext        string
+	KubeConfig         string
 	WatchPollInterval  int
 	DefaultRepo        string
 	CustomLabels       []string

pkg/skaffold/kubernetes/context/context.go

@@ -33,23 +33,26 @@ var (
 )
 
 var (
-	kubeConfigOnce  sync.Once
-	kubeConfig      clientcmd.ClientConfig
-	kubeContextOnce sync.Once
-	kubeContext     string
+	kubeConfigOnce sync.Once
+	kubeConfig     clientcmd.ClientConfig
+
+	configureOnce  sync.Once
+	kubeContext    string
+	kubeConfigFile string
 )
 
-// UseKubeContext sets an override for the current context in the k8s config.
+// ConfigureKubeConfig sets an override for the current context in the k8s config.
 // When given, the firstCliValue always takes precedence over the yamlValue.
 // Changing the kube-context of a running Skaffold process is not supported, so
 // after the first call, the kube-context will be locked.
-func UseKubeContext(cliValue, yamlValue string) {
-	newKubeContext := yamlValue
-	if cliValue != "" {
-		newKubeContext = cliValue
+func ConfigureKubeConfig(cliKubeConfig, cliKubeContext, yamlKubeContext string) {
+	newKubeContext := yamlKubeContext
+	if cliKubeContext != "" {
+		newKubeContext = cliKubeContext
 	}
-	kubeContextOnce.Do(func() {
+	configureOnce.Do(func() {
 		kubeContext = newKubeContext
+		kubeConfigFile = cliKubeConfig
 		if kubeContext != "" {
 			logrus.Infof("Activated kube-context %q", kubeContext)
 		}
@@ -60,23 +63,23 @@ func UseKubeContext(cliValue, yamlValue string) {
 }
 
 // GetRestClientConfig returns a REST client config for API calls against the Kubernetes API.
-// If UseKubeContext was called before, the CurrentContext will be overridden.
+// If ConfigureKubeConfig was called before, the CurrentContext will be overridden.
 // The kubeconfig used will be cached for the life of the skaffold process after the first call.
 // If the CurrentContext is empty and the resulting config is empty, this method attempts to
 // create a RESTClient with an in-cluster config.
 func GetRestClientConfig() (*restclient.Config, error) {
-	return getRestClientConfig(kubeContext)
+	return getRestClientConfig(kubeContext, kubeConfigFile)
 }
 
-func getRestClientConfig(kctx string) (*restclient.Config, error) {
+func getRestClientConfig(kctx string, kcfg string) (*restclient.Config, error) {
 	logrus.Debugf("getting client config for kubeContext: `%s`", kctx)
 	rawConfig, err := getRawKubeConfig()
 	if err != nil {
 		return nil, err
 	}
 	clientConfig := clientcmd.NewNonInteractiveClientConfig(rawConfig, kctx, &clientcmd.ConfigOverrides{CurrentContext: kctx}, nil)
 	restConfig, err := clientConfig.ClientConfig()
-	if kctx == "" && clientcmd.IsEmptyConfig(err) {
+	if kctx == "" && kcfg == "" && clientcmd.IsEmptyConfig(err) {
 		logrus.Debug("no kube-context set and no kubeConfig found, attempting in-cluster config")
 		restConfig, err := restclient.InClusterConfig()
 		return restConfig, errors.Wrap(err, "error creating REST client config in-cluster")
@@ -85,7 +88,7 @@ func getRestClientConfig(kctx string) (*restclient.Config, error) {
 	return restConfig, errors.Wrapf(err, "error creating REST client config for kubeContext '%s'", kctx)
 }
 
-// getCurrentConfig retrieves the kubeconfig file. If UseKubeContext was called before, the CurrentContext will be overridden.
+// getCurrentConfig retrieves the kubeconfig file. If ConfigureKubeConfig was called before, the CurrentContext will be overridden.
 // The result will be cached after the first call.
 func getCurrentConfig() (clientcmdapi.Config, error) {
 	cfg, err := getRawKubeConfig()
@@ -101,6 +104,7 @@ func getCurrentConfig() (clientcmdapi.Config, error) {
 func getRawKubeConfig() (clientcmdapi.Config, error) {
 	kubeConfigOnce.Do(func() {
 		loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
+		loadingRules.ExplicitPath = kubeConfigFile
 		kubeConfig = clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, &clientcmd.ConfigOverrides{
 			CurrentContext: kubeContext,
 		})

pkg/skaffold/kubernetes/context/context_test.go

@@ -66,9 +66,13 @@ clusters:
 contexts:
 - context:
     cluster: cluster-bar
-    user: user1
-  name: cluster-bar
-current-context: cluster-foo
+    user: user-bar
+  name: context-bar
+- context:
+    cluster: cluster-bar
+    user: user-baz
+  name: context-baz
+current-context: context-baz
 users:
 - name: user1
   user:
@@ -96,6 +100,17 @@ func TestCurrentContext(t *testing.T) {
 		t.CheckDeepEqual(clusterBarContext, config.CurrentContext)
 	})
 
+	testutil.Run(t, "kubeconfig CLI flag takes precedence", func(t *testutil.T) {
+		resetKubeConfig(t, validKubeConfig)
+		kubeConfig := t.TempFile("config", []byte(changedKubeConfig))
+
+		kubeConfigFile = kubeConfig
+		config, err := CurrentConfig()
+
+		t.CheckNoError(err)
+		t.CheckDeepEqual("context-baz", config.CurrentContext)
+	})
+
 	testutil.Run(t, "invalid context", func(t *testutil.T) {
 		resetKubeConfig(t, "invalid")
 
@@ -172,7 +187,7 @@ func TestGetRestClientConfig(t *testing.T) {
 		t.SetEnvs(map[string]string{"KUBECONFIG": "non-valid"})
 		resetConfig()
 
-		_, err := getRestClientConfig("")
+		_, err := getRestClientConfig("", "")
 
 		if err == nil {
 			t.Errorf("expected error outside the cluster")
@@ -258,7 +273,7 @@ func TestUseKubeContext(t *testing.T) {
 		testutil.Run(t, test.name, func(t *testutil.T) {
 			kubeContext = ""
 			for _, inv := range test.invocations {
-				UseKubeContext(inv.cliValue, inv.yamlValue)
+				ConfigureKubeConfig("", inv.cliValue, inv.yamlValue)
 			}
 
 			t.CheckDeepEqual(test.expected, kubeContext)
@@ -270,12 +285,13 @@ func TestUseKubeContext(t *testing.T) {
 // resetConfig is used by tests
 func resetConfig() {
 	kubeConfigOnce = sync.Once{}
-	kubeContextOnce = sync.Once{}
+	configureOnce = sync.Once{}
 }
 
 func resetKubeConfig(t *testutil.T, content string) {
 	kubeConfig := t.TempFile("config", []byte(content))
 	t.SetEnvs(map[string]string{"KUBECONFIG": kubeConfig})
 	kubeContext = ""
+	kubeConfigFile = ""
 	resetConfig()
 }