chore: remove duplicated logic by function call (opendatahub-io#1080)

* chore: remove duplicated logic by function call
- change if-else-if to switch
- fast return in recreateSecret case

---------
Signed-off-by: Wen Zhou <wenzhou@redhat.com>

pkg/cluster/cert.go

@@ -32,27 +32,9 @@ func CreateSelfSignedCertificate(ctx context.Context, c client.Client, secretNam
 	if err := ApplyMetaOptions(certSecret, metaOptions...); err != nil {
 		return err
 	}
-	existingSecret := &corev1.Secret{}
-	err = c.Get(ctx, client.ObjectKey{Name: secretName, Namespace: namespace}, existingSecret)
-	if err != nil {
-		if k8serr.IsNotFound(err) {
-			// Secret does not exist, create it
-			if createErr := c.Create(ctx, certSecret); createErr != nil {
-				return fmt.Errorf("failed creating certificate secret: %w", createErr)
-			}
-		} else {
-			return fmt.Errorf("failed getting certificate secret: %w", err)
-		}
-	} else if existingSecret.Type != certSecret.Type {
-		// Secret exists but with a different type, delete and recreate it
-		if err := c.Delete(ctx, existingSecret); err != nil {
-			return fmt.Errorf("failed deleting existing secret: %w", err)
-		}
-		if createErr := c.Create(ctx, certSecret); client.IgnoreAlreadyExists(createErr) != nil {
-			return fmt.Errorf("failed creating certificate secret: %w", createErr)
-		}
+	if err = generateCertSecret(ctx, c, certSecret, secretName, namespace); err != nil {
+		return fmt.Errorf("failed update self-signed certificate secret: %w", err)
 	}
-
 	return nil
 }
 
@@ -194,43 +176,51 @@ func copySecretToNamespace(ctx context.Context, c client.Client, secret *corev1.
 		Data: secret.Data,
 		Type: secret.Type,
 	}
-
-	existingSecret := &corev1.Secret{}
-	err := c.Get(ctx, client.ObjectKey{Name: newSecretName, Namespace: namespace}, existingSecret)
-	if k8serr.IsNotFound(err) { // create if not found
-		if err = c.Create(ctx, newSecret); err != nil {
-			return fmt.Errorf("failed to create new secret: %w", err)
-		}
-	} else if err != nil {
-		return fmt.Errorf("failed to get existing secret: %w", err)
+	if err := generateCertSecret(ctx, c, newSecret, newSecretName, namespace); err != nil {
+		return fmt.Errorf("failed to deploy default cert secret to namespace %s: %w", namespace, err)
 	}
-
-	if existingSecret.Type != newSecret.Type { // recreate if found with mismatched type
-		if recreateSecret(ctx, c, existingSecret, newSecret) != nil {
-			return errors.New("failed to recreate secret with type corrected")
-		}
-	}
-
-	if isSecretOutdated(existingSecret.Data, newSecret.Data) {
-		if err = c.Update(ctx, newSecret); err != nil { // update data if found with same type but outdated content
-			return fmt.Errorf("failed to update secret: %w", err)
-		}
-	}
-
 	return nil
 }
 
 // recreateSecret deletes the existing secret and creates a new one.
 func recreateSecret(ctx context.Context, c client.Client, existingSecret, newSecret *corev1.Secret) error {
 	if err := c.Delete(ctx, existingSecret); err != nil {
-		return fmt.Errorf("failed to delete existing secret: %w", err)
+		return fmt.Errorf("failed to delete existing secret before recreating new one: %w", err)
 	}
 	if err := c.Create(ctx, newSecret); err != nil {
-		return fmt.Errorf("failed to create new secret: %w", err)
+		return fmt.Errorf("failed to create new secret after existing one has been deleted: %w", err)
 	}
 	return nil
 }
 
+// generateCertSecret creates a secret if it does not exist;  recreate this secret if type not match; update data if outdated.
+func generateCertSecret(ctx context.Context, c client.Client, certSecret *corev1.Secret, secretName, namespace string) error {
+	existingSecret := &corev1.Secret{}
+	err := c.Get(ctx, client.ObjectKey{Name: secretName, Namespace: namespace}, existingSecret)
+	switch {
+	case err == nil:
+		// Secret exists but with a different type, delete and create it again
+		if existingSecret.Type != certSecret.Type {
+			return recreateSecret(ctx, c, existingSecret, certSecret)
+		}
+		// update data if found with same type but outdated content
+		if isSecretOutdated(existingSecret.Data, certSecret.Data) {
+			if err = c.Update(ctx, certSecret); err != nil {
+				return fmt.Errorf("failed to update existing secret: %w", err)
+			}
+		}
+	case k8serr.IsNotFound(err):
+		// Secret does not exist, create it
+		if err := c.Create(ctx, certSecret); err != nil {
+			return fmt.Errorf("failed creating new certificate secret: %w", err)
+		}
+	default:
+		return fmt.Errorf("failed getting certificate secret: %w", err)
+	}
+
+	return nil
+}
+
 // isSecretOutdated compares two secret data of type map[string][]byte and returns true if they are not equal.
 func isSecretOutdated(existingSecretData, newSecretData map[string][]byte) bool {
 	if len(existingSecretData) != len(newSecretData) {