feat: add lazy loading kubeconfigs for Test Steps (#540)

Signed-off-by: Kumar Mallikarjuna <[email protected]>

docs/testing/reference.md

@@ -73,6 +73,7 @@ delete   | list of object references | A list of objects to delete, if they do n
 index    | int                       | Override the test step's index.
 commands | list of [Commands](#commands) | Commands to run prior at the beginning of the test step.
 kubeconfig    | string                       | The Kubeconfig file to use to run the included steps(s).
+kubeconfigLoading    | string                | Specifies the mode for loading Kubeconfig and making a cluster connection: `Eager` (when loading the test definition) or `Lazy` (right before executing the step, makes it possible to generate the Kubeconfig in a preceding step). Defaults to `Eager`.
 unitTest    | bool                       | Indicates if the step is a unit test, safe to run without a real Kubernetes cluster.
 
 

pkg/apis/testharness/v1beta1/test_types.go

@@ -6,6 +6,9 @@ import (
 	"k8s.io/client-go/rest"
 )
 
+const KubeconfigLoadingEager = "Eager"
+const KubeconfigLoadingLazy = "Lazy"
+
 // Create embedded struct to implement custom DeepCopyInto method
 type RestConfig struct {
 	RC *rest.Config
@@ -125,6 +128,11 @@ type TestStep struct {
 
 	// Kubeconfig to use when applying and asserting for this step.
 	Kubeconfig string `json:"kubeconfig,omitempty"`
+
+	// Specifies the mode for loading Kubeconfig: Eager/Lazy. Defaults to Eager.
+	// +kubebuilder:default=Eager
+	// +kubebuilder:validation:Enum=Eager;Lazy
+	KubeconfigLoading string `json:"kubeconfigLoading,omitempty"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

pkg/test/case.go

@@ -25,6 +25,7 @@ import (
 
 	"k8s.io/client-go/tools/clientcmd"
 
+	"github.com/kudobuilder/kuttl/pkg/apis/testharness/v1beta1"
 	"github.com/kudobuilder/kuttl/pkg/report"
 	testutils "github.com/kudobuilder/kuttl/pkg/test/utils"
 )
@@ -333,11 +334,11 @@ func (t *Case) Run(test *testing.T, ts *report.Testsuite) {
 	clients := map[string]client.Client{"": cl}
 
 	for _, testStep := range t.Steps {
-		if clients[testStep.Kubeconfig] != nil {
+		if clients[testStep.Kubeconfig] != nil || testStep.KubeconfigLoading == v1beta1.KubeconfigLoadingLazy {
 			continue
 		}
 
-		cl, err := newClient(testStep.Kubeconfig)(false)
+		cl, err = newClient(testStep.Kubeconfig)(false)
 		if err != nil {
 			setupReport.Failure = report.NewFailure(err.Error(), nil)
 			ts.AddTestcase(setupReport)
@@ -347,9 +348,11 @@ func (t *Case) Run(test *testing.T, ts *report.Testsuite) {
 		clients[testStep.Kubeconfig] = cl
 	}
 
-	for _, c := range clients {
-		if err := t.CreateNamespace(test, c, ns); err != nil {
-			setupReport.Failure = report.NewFailure(err.Error(), nil)
+	for kc, c := range clients {
+		if err = t.CreateNamespace(test, c, ns); k8serrors.IsAlreadyExists(err) {
+			t.Logger.Logf("namespace %q already exists, using kubeconfig %q", ns.Name, kc)
+		} else if err != nil {
+			setupReport.Failure = report.NewFailure("failed to create test namespace", []error{err})
 			ts.AddTestcase(setupReport)
 			test.Fatal(err)
 		}
@@ -370,7 +373,25 @@ func (t *Case) Run(test *testing.T, ts *report.Testsuite) {
 		tc.Assertions += len(testStep.Asserts)
 		tc.Assertions += len(testStep.Errors)
 
-		errs := testStep.Run(test, ns.Name)
+		errs := []error{}
+
+		// Set-up client/namespace for lazy-loaded Kubeconfig
+		if testStep.KubeconfigLoading == v1beta1.KubeconfigLoadingLazy {
+			cl, err = testStep.Client(false)
+			if err != nil {
+				errs = append(errs, fmt.Errorf("failed to lazy-load kubeconfig: %w", err))
+			} else if err = t.CreateNamespace(test, cl, ns); k8serrors.IsAlreadyExists(err) {
+				t.Logger.Logf("namespace %q already exists", ns.Name)
+			} else if err != nil {
+				errs = append(errs, fmt.Errorf("failed to create test namespace: %w", err))
+			}
+		}
+
+		// Run test case only if no setup errors are encountered
+		if len(errs) == 0 {
+			errs = append(errs, testStep.Run(test, ns.Name)...)
+		}
+
 		if len(errs) > 0 {
 			caseErr := fmt.Errorf("failed in step %s", testStep.String())
 			tc.Failure = report.NewFailure(caseErr.Error(), errs)

pkg/test/step.go

@@ -51,9 +51,10 @@ type Step struct {
 
 	Timeout int
 
-	Kubeconfig      string
-	Client          func(forceNew bool) (client.Client, error)
-	DiscoveryClient func() (discovery.DiscoveryInterface, error)
+	Kubeconfig        string
+	KubeconfigLoading string
+	Client            func(forceNew bool) (client.Client, error)
+	DiscoveryClient   func() (discovery.DiscoveryInterface, error)
 
 	Logger testutils.Logger
 }
@@ -555,6 +556,13 @@ func (s *Step) LoadYAML(file string) error {
 				exKubeconfig := env.Expand(s.Step.Kubeconfig)
 				s.Kubeconfig = cleanPath(exKubeconfig, s.Dir)
 			}
+
+			switch s.Step.KubeconfigLoading {
+			case "", harness.KubeconfigLoadingEager, harness.KubeconfigLoadingLazy:
+				s.KubeconfigLoading = s.Step.KubeconfigLoading
+			default:
+				return fmt.Errorf("attribute 'kubeconfigLoading' has invalid value %q", s.Step.KubeconfigLoading)
+			}
 		} else {
 			applies = append(applies, obj)
 		}