check cluster

Author: Stevent-fei

Diff for: cmd/sealer/cmd/cluster/run.go

@@ -56,9 +56,6 @@ run cluster by CLI flags:
 
 run app image:
   sealer run localhost/nginx:v1
-
-run upgrade image:
-  sealer run docker.io/sealerio/kubernetes:v1.22.15-upgrade --mode upgrade
 `
 
 func NewRunCmd() *cobra.Command {
@@ -524,12 +521,12 @@ func prepareMaterials(infraDriver infradriver.InfraDriver, imageEngine imageengi
 func checkClusterIsExists(cf clusterfile.Interface) error {
 	rawCluster := cf.GetCluster()
 	clusterFile, _, err := clusterfile.GetActualClusterFile()
-	if err != nil {
-		return nil
-	}
-	cluster := clusterFile.GetCluster()
-	if cluster.Spec.Image != rawCluster.Spec.Image {
-		return fmt.Errorf("the cluster image already exists, please uninstall the current cluster and install another version of the cluster image")
+	if err == nil {
+		cluster := clusterFile.GetCluster()
+		if cluster.Spec.Image != rawCluster.Spec.Image {
+			return fmt.Errorf("the cluster image already exists, please uninstall the current cluster and install another version of the cluster image")
+		}
+		return fmt.Errorf("this cluster image has already been installed, please do not repeat the operation")
 	}
-	return fmt.Errorf("this cluster image has already been installed, please do not repeat the operation")
+	return nil
 }