Saas detection error handling (#493)

Paired with @oleschoenburg on this:

* We agreed on to "simply" pass the error to the front, to the
respective commands so they can either fail or do what ever
* For errors indicating resource not-found we decided to return false,
and use SM setting (as we expect this CRD not in the SM env)
 * We wrote some more tests for the error handling
* I had to refactor a bit the client creation, so we test the right
things here


closes #488 
closes #490

go-chaos/internal/helper_test.go

@@ -119,7 +119,9 @@ func (c *K8Client) createSaaSCRD(t *testing.T) {
 	_, err := c.DynamicClient.Resource(zeebeCrd).Create(context.TODO(), obj, metav1.CreateOptions{})
 	require.NoError(t, err)
 
-	c.SaaSEnv = c.isSaaSEnvironment()
+	saas, err := c.isSaaSEnvironment()
+	require.NoError(t, err)
+	c.SaaSEnv = saas
 }
 
 func (c K8Client) CreateStatefulSetWithLabelsAndName(t *testing.T, selector *metav1.LabelSelector, name string) {

go-chaos/internal/k8helper.go

@@ -49,6 +49,26 @@ func CreateK8Client(kubeConfigPath string, namespace string) (K8Client, error) {
 }
 
 func createK8Client(settings KubernetesSettings) (K8Client, error) {
+	client, err := internalCreateClient(settings)
+	if err != nil {
+		return client, err
+	}
+
+	client.SaaSEnv, err = client.isSaaSEnvironment()
+	if err != nil {
+		return client, err
+	}
+
+	if client.SaaSEnv {
+		LogVerbose("Running experiment in SaaS environment.")
+	} else {
+		LogVerbose("Running experiment in self-managed environment.")
+	}
+
+	return client, nil
+}
+
+func internalCreateClient(settings KubernetesSettings) (K8Client, error) {
 	clientConfig := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
 		&clientcmd.ClientConfigLoadingRules{ExplicitPath: settings.kubeConfigPath},
 		&clientcmd.ConfigOverrides{Context: api.Context{Namespace: settings.namespace}})
@@ -73,14 +93,6 @@ func createK8Client(settings KubernetesSettings) (K8Client, error) {
 	}
 
 	client := K8Client{Clientset: clientset, ClientConfig: clientConfig, DynamicClient: dynamicClient}
-	client.SaaSEnv = client.isSaaSEnvironment()
-
-	if client.SaaSEnv {
-		LogVerbose("Running experiment in SaaS environment.")
-	} else {
-		LogVerbose("Running experiment in self-managed environment.")
-	}
-
 	return client, nil
 }
 

go-chaos/internal/k8helper_test.go

@@ -28,7 +28,7 @@ func Test_CreateK8ClientWithPath(t *testing.T) {
 	settings := KubernetesSettings{kubeConfigPath: "kubeconfigtest.yml"}
 
 	// when
-	client, err := createK8Client(settings)
+	client, err := internalCreateClient(settings)
 
 	// then
 	assert.NoError(t, err)
@@ -40,7 +40,7 @@ func Test_CreateK8ClientWithPath(t *testing.T) {
 func Test_ShouldReturnNamespace(t *testing.T) {
 	// given
 	settings := KubernetesSettings{kubeConfigPath: "kubeconfigtest.yml"}
-	client, err := createK8Client(settings)
+	client, err := internalCreateClient(settings)
 	require.NoError(t, err)
 
 	// when
@@ -57,7 +57,7 @@ func Test_ShouldReturnNamespace(t *testing.T) {
 func Test_ShouldReturnNamespaceOverride(t *testing.T) {
 	// given
 	settings := KubernetesSettings{kubeConfigPath: "kubeconfigtest.yml", namespace: "namespace-override"}
-	client, err := createK8Client(settings)
+	client, err := internalCreateClient(settings)
 	require.NoError(t, err)
 
 	// when

go-chaos/internal/saas.go

@@ -17,6 +17,7 @@ package internal
 import (
 	"context"
 	"fmt"
+	"k8s.io/apimachinery/pkg/api/errors"
 	"strings"
 
 	meta "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -55,15 +56,15 @@ func (c K8Client) setPauseFlag(pauseEnabled bool) error {
 	return err
 }
 
-func (c K8Client) isSaaSEnvironment() bool {
+func (c K8Client) isSaaSEnvironment() (bool, error) {
 	namespace := c.GetCurrentNamespace()
 	clusterId := strings.TrimSuffix(namespace, "-zeebe")
 	zeebeCrd := schema.GroupVersionResource{Group: "cloud.camunda.io", Version: "v1alpha1", Resource: "zeebeclusters"}
 	resource, err := c.DynamicClient.Resource(zeebeCrd).Get(context.TODO(), clusterId, meta.GetOptions{})
 
-	if err != nil {
-		LogInfo("Failed to retrieve SaaS CRD, fallback to self-managed mode. %v", err)
-		return false
+	if errors.IsNotFound(err) {
+		return false, nil
 	}
-	return resource != nil
+
+	return resource != nil, err
 }

go-chaos/internal/saas_test.go

@@ -15,9 +15,16 @@
 package internal
 
 import (
+	"errors"
+	"github.com/stretchr/testify/require"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	dynamicFake "k8s.io/client-go/dynamic/fake"
+	k8testing "k8s.io/client-go/testing"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	k8errors "k8s.io/apimachinery/pkg/api/errors"
 )
 
 func Test_ShouldReturnTrueWhenCRDDeployed(t *testing.T) {
@@ -26,8 +33,9 @@ func Test_ShouldReturnTrueWhenCRDDeployed(t *testing.T) {
 	k8Client.createSaaSCRD(t)
 
 	// when
-	isSaaSEnvironment := k8Client.isSaaSEnvironment()
+	isSaaSEnvironment, err := k8Client.isSaaSEnvironment()
 
+	require.NoError(t, err)
 	assert.True(t, isSaaSEnvironment)
 }
 
@@ -36,7 +44,40 @@ func Test_ShouldReturnFalseWhenNoCRDDeployed(t *testing.T) {
 	k8Client := CreateFakeClient()
 
 	// when
-	isSaaSEnvironment := k8Client.isSaaSEnvironment()
+	isSaaSEnvironment, err := k8Client.isSaaSEnvironment()
 
+	require.NoError(t, err)
+	assert.False(t, isSaaSEnvironment)
+}
+
+func Test_ShouldThrowErrorWhenNoCRDDeployed(t *testing.T) {
+	// given
+	k8Client := CreateFakeClient()
+	k8Client.DynamicClient.(*dynamicFake.FakeDynamicClient).Fake.PrependReactor("get", "zeebeclusters", func(action k8testing.Action) (handled bool, ret runtime.Object, err error) {
+		return true, nil, errors.New("timeout")
+	})
+
+	// when
+	isSaaSEnvironment, err := k8Client.isSaaSEnvironment()
+
+	require.Error(t, err)
+	assert.False(t, isSaaSEnvironment)
+}
+
+func Test_ShouldReturnFalseOnNotFound(t *testing.T) {
+	// given
+	k8Client := CreateFakeClient()
+	k8Client.DynamicClient.(*dynamicFake.FakeDynamicClient).Fake.PrependReactor("get", "zeebeclusters", func(action k8testing.Action) (handled bool, ret runtime.Object, err error) {
+		return true, nil, k8errors.NewNotFound(
+			schema.GroupResource{
+				Group:    "cloud.camunda.io",
+				Resource: "zeebeclusters"},
+			"test")
+	})
+
+	// when
+	isSaaSEnvironment, err := k8Client.isSaaSEnvironment()
+
+	require.NoError(t, err)
 	assert.False(t, isSaaSEnvironment)
 }