[Feature] Accept Kubeconfig ENV (#543)

Author: ajanikow

main.go

@@ -275,7 +275,7 @@ func newOperatorConfigAndDeps(id, namespace, name string) (operator.Config, oper
 	if err != nil {
 		return operator.Config{}, operator.Dependencies{}, maskAny(fmt.Errorf("Failed to create k8b api extensions client: %s", err))
 	}
-	crCli, err := client.NewInCluster()
+	crCli, err := client.NewClient()
 	if err != nil {
 		return operator.Config{}, operator.Dependencies{}, maskAny(fmt.Errorf("Failed to created versioned client: %s", err))
 	}

pkg/client/client.go

@@ -34,10 +34,10 @@ var (
 	maskAny = errors.WithStack
 )
 
-// MustNewInCluster creates an in-cluster client, or panics
+// MustNewClient creates an client, or panics
 // when a failure is detected.
-func MustNewInCluster() versioned.Interface {
-	cli, err := NewInCluster()
+func MustNewClient() versioned.Interface {
+	cli, err := NewClient()
 	if err != nil {
 		panic(err)
 	}
@@ -54,10 +54,10 @@ func MustNew(cfg *rest.Config) versioned.Interface {
 	return cli
 }
 
-// NewInCluster creates an in-cluster client, or returns an error
+// NewClient creates an client, or returns an error
 // when a failure is detected.
-func NewInCluster() (versioned.Interface, error) {
-	cfg, err := k8sutil.InClusterConfig()
+func NewClient() (versioned.Interface, error) {
+	cfg, err := k8sutil.NewKubeConfig()
 	if err != nil {
 		return nil, maskAny(err)
 	}

pkg/deployment/resources/servicemonitor.go

@@ -57,7 +57,7 @@ func (r *Resources) EnsureMonitoringClient() (*clientv1.MonitoringV1Client, erro
 
 	// Make a client:
 	var restConfig *rest.Config
-	restConfig, err := k8sutil.InClusterConfig()
+	restConfig, err := k8sutil.NewKubeConfig()
 	if err != nil {
 		return nil, maskAny(err)
 	}

pkg/util/k8sutil/client.go

@@ -23,17 +23,45 @@
 package k8sutil
 
 import (
-	"net"
+	"fmt"
 	"os"
 
+	"github.com/arangodb/kube-arangodb/pkg/util"
+	"k8s.io/client-go/tools/clientcmd"
+
 	apiextensionsclient "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 )
 
+const Kubeconfig util.EnvironmentVariable = "KUBECONFIG"
+
+// NewKubeConfig loads config from KUBECONFIG or as incluster
+func NewKubeConfig() (*rest.Config, error) {
+	// If KUBECONFIG is defined use this variable
+	if kubeconfig, ok := Kubeconfig.Lookup(); ok {
+		return clientcmd.BuildConfigFromFlags("", kubeconfig)
+	}
+
+	// Try to load incluster config
+	if cfg, err := rest.InClusterConfig(); err == nil {
+		return cfg, nil
+	} else if err != rest.ErrNotInCluster {
+		return nil, err
+	}
+
+	// At the end try to use default path
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return nil, err
+	}
+
+	return clientcmd.BuildConfigFromFlags("", fmt.Sprintf("%s/.kube/config", home))
+}
+
 // NewKubeClient creates a new k8s client
 func NewKubeClient() (kubernetes.Interface, error) {
-	cfg, err := InClusterConfig()
+	cfg, err := NewKubeConfig()
 	if err != nil {
 		return nil, maskAny(err)
 	}
@@ -55,7 +83,7 @@ func MustNewKubeClient() kubernetes.Interface {
 
 // NewKubeExtClient creates a new k8s api extensions client
 func NewKubeExtClient() (apiextensionsclient.Interface, error) {
-	cfg, err := InClusterConfig()
+	cfg, err := NewKubeConfig()
 	if err != nil {
 		return nil, maskAny(err)
 	}
@@ -65,24 +93,3 @@ func NewKubeExtClient() (apiextensionsclient.Interface, error) {
 	}
 	return c, nil
 }
-
-// InClusterConfig loads the environment into a rest config.
-func InClusterConfig() (*rest.Config, error) {
-	// Work around https://github.com/kubernetes/kubernetes/issues/40973
-	// See https://github.com/coreos/etcd-operator/issues/731#issuecomment-283804819
-	if len(os.Getenv("KUBERNETES_SERVICE_HOST")) == 0 {
-		addrs, err := net.LookupHost("kubernetes.default.svc")
-		if err != nil {
-			return nil, maskAny(err)
-		}
-		os.Setenv("KUBERNETES_SERVICE_HOST", addrs[0])
-	}
-	if len(os.Getenv("KUBERNETES_SERVICE_PORT")) == 0 {
-		os.Setenv("KUBERNETES_SERVICE_PORT", "443")
-	}
-	cfg, err := rest.InClusterConfig()
-	if err != nil {
-		return nil, maskAny(err)
-	}
-	return cfg, nil
-}

reboot.go

@@ -386,7 +386,7 @@ func cmdRebootRun(cmd *cobra.Command, args []string) {
 		cliLog.Fatal().Err(err).Msg("Failed to create Kubernetes client")
 	}
 
-	extcli, err := extclient.NewInCluster()
+	extcli, err := extclient.NewClient()
 	if err != nil {
 		cliLog.Fatal().Err(err).Msg("failed to create arango extension client")
 	}

tests/annotations_test.go

@@ -184,7 +184,7 @@ func ensureAnnotations(t *testing.T, client kubernetes.Interface, depl *api.Aran
 
 func TestAnnotations(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 

tests/auth_test.go

@@ -41,7 +41,7 @@ import (
 // with default authentication (on) using a generated JWT secret.
 func TestAuthenticationSingleDefaultSecret(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -89,7 +89,7 @@ func TestAuthenticationSingleDefaultSecret(t *testing.T) {
 // with default authentication (on) using a user created JWT secret.
 func TestAuthenticationSingleCustomSecret(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 	secrets := kubecli.CoreV1().Secrets(ns)
@@ -140,7 +140,7 @@ func TestAuthenticationSingleCustomSecret(t *testing.T) {
 // with authentication set to `None`.
 func TestAuthenticationNoneSingle(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -179,7 +179,7 @@ func TestAuthenticationNoneSingle(t *testing.T) {
 // with default authentication (on) using a generated JWT secret.
 func TestAuthenticationClusterDefaultSecret(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -227,7 +227,7 @@ func TestAuthenticationClusterDefaultSecret(t *testing.T) {
 // with default authentication (on) using a user created JWT secret.
 func TestAuthenticationClusterCustomSecret(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 	secrets := kubecli.CoreV1().Secrets(ns)
@@ -280,7 +280,7 @@ func TestAuthenticationClusterCustomSecret(t *testing.T) {
 // with authentication set to `None`.
 func TestAuthenticationNoneCluster(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 

tests/backup_test.go

@@ -317,9 +317,9 @@ func compareBackup(t *testing.T, meta driver.BackupMeta, backup *backupApi.Arang
 
 func TestBackupCluster(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
-	deploymentClient := kubeArangoClient.MustNewInCluster()
+	deploymentClient := kubeArangoClient.MustNewClient()
 	ns := getNamespace(t)
 
 	backupPolicyClient := deploymentClient.BackupV1().ArangoBackupPolicies(ns)

tests/change_args_test.go

@@ -42,7 +42,7 @@ import (
 // with default settings and once ready changes the arguments of the agents.
 func TestChangeArgsAgents(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -121,7 +121,7 @@ func TestChangeArgsAgents(t *testing.T) {
 // with default settings and once ready changes the arguments of the dbservers.
 func TestChangeArgsDBServer(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 

tests/cursor_test.go

@@ -40,7 +40,7 @@ import (
 // with default settings and runs some cursor requests on it.
 func TestCursorSingle(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -84,7 +84,7 @@ func TestCursorSingle(t *testing.T) {
 // with default settings.
 func TestCursorActiveFailover(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)
 
@@ -128,7 +128,7 @@ func TestCursorActiveFailover(t *testing.T) {
 // with default settings.
 func TestCursorCluster(t *testing.T) {
 	longOrSkip(t)
-	c := client.MustNewInCluster()
+	c := client.MustNewClient()
 	kubecli := mustNewKubeClient(t)
 	ns := getNamespace(t)