fix: change way of returns service bus namespace object

CHANGELOG.md

@@ -78,6 +78,7 @@ Here is an overview of all new **experimental** features:
 - **General**: Fix regression in fallback mechanism ([#4249](https://github.com/kedacore/keda/issues/4249))
 - **General**: Prevent a panic that might occur while refreshing a scaler cache ([#4092](https://github.com/kedacore/keda/issues/4092))
 - **Azure Service Bus Scaler:** Use correct auth flows with pod identity ([#4026](https://github.com/kedacore/keda/issues/4026)|[#4123](https://github.com/kedacore/keda/issues/4123))
+- **Azure Service Bus Scaler:**: Change way of get service bus namespace  ([#4262](https://github.com/kedacore/keda/issues/4262))
 - **Cassandra Scaler**: Checking whether the port information is entered in the ClusterIPAddres is done correctly. ([#4110](https://github.com/kedacore/keda/issues/4110))
 - **CPU Memory Scaler** Store forgotten logger ([#4022](https://github.com/kedacore/keda/issues/4022))
 - **Datadog Scaler**: Return correct error when getting a 429 error ([#4187](https://github.com/kedacore/keda/issues/4187))

pkg/scalers/azure_servicebus_scaler.go

@@ -291,18 +291,23 @@ func (s *azureServiceBusScaler) getServiceBusAdminClient() (*admin.Client, error
 	if s.client != nil {
 		return s.client, nil
 	}
-
+	var err error
+	var client *admin.Client
 	switch s.podIdentity.Provider {
 	case "", kedav1alpha1.PodIdentityProviderNone:
-		return admin.NewClientFromConnectionString(s.metadata.connection, nil)
+		client, err = admin.NewClientFromConnectionString(s.metadata.connection, nil)
 	case kedav1alpha1.PodIdentityProviderAzure, kedav1alpha1.PodIdentityProviderAzureWorkload:
-		creds, err := azure.NewChainedCredential(s.podIdentity.IdentityID, s.podIdentity.Provider)
-		if err != nil {
-			return nil, err
+		creds, chainedErr := azure.NewChainedCredential(s.podIdentity.IdentityID, s.podIdentity.Provider)
+		if chainedErr != nil {
+			return nil, chainedErr
 		}
-		return admin.NewClient(s.metadata.fullyQualifiedNamespace, creds, nil)
+		client, err = admin.NewClient(s.metadata.fullyQualifiedNamespace, creds, nil)
+	default:
+		err = fmt.Errorf("incorrect podIdentity type")
 	}
-	return nil, fmt.Errorf("incorrect podIdentity type")
+
+	s.client = client
+	return client, err
 }
 
 func getQueueLength(ctx context.Context, adminClient *admin.Client, meta *azureServiceBusMetadata) (int64, error) {

pkg/scalers/azure_servicebus_scaler_test.go

@@ -23,6 +23,7 @@ import (
 	"testing"
 
 	"github.com/go-logr/logr"
+	"github.com/stretchr/testify/assert"
 
 	kedav1alpha1 "github.com/kedacore/keda/v2/apis/keda/v1alpha1"
 )
@@ -189,6 +190,24 @@ func TestParseServiceBusMetadata(t *testing.T) {
 	}
 }
 
+func TestGetServiceBusAdminClientIsCached(t *testing.T) {
+	testData := azServiceBusMetricIdentifiers[0]
+	meta, err := parseAzureServiceBusMetadata(&ScalerConfig{ResolvedEnv: connectionResolvedEnv,
+		TriggerMetadata: testData.metadataTestData.metadata, AuthParams: testData.metadataTestData.authParams,
+		PodIdentity: kedav1alpha1.AuthPodIdentity{Provider: testData.metadataTestData.podIdentity}, ScalerIndex: testData.scalerIndex},
+		logr.Discard())
+	if err != nil {
+		t.Fatal("Could not parse metadata:", err)
+	}
+	mockAzServiceBusScalerScaler := azureServiceBusScaler{
+		metadata:    meta,
+		podIdentity: kedav1alpha1.AuthPodIdentity{Provider: testData.metadataTestData.podIdentity},
+	}
+
+	_, _ = mockAzServiceBusScalerScaler.getServiceBusAdminClient()
+	assert.NotNil(t, mockAzServiceBusScalerScaler.client)
+}
+
 func TestGetServiceBusLength(t *testing.T) {
 	t.Log("This test will use the environment variable SERVICEBUS_CONNECTION_STRING if it is set")
 	t.Log("If set, it will connect to the servicebus namespace specified by the connection string & check:")