fix the panic of cli

Signed-off-by: maanugh <[email protected]>

pkg/cmd/describe/describe_rollout.go

@@ -112,7 +112,6 @@ func NewCmdDescribeRollout(f cmdutil.Factory, streams genericclioptions.IOStream
 		Aliases:               []string{"rollouts", "ro"},
 		Run: func(cmd *cobra.Command, args []string) {
 			cmdutil.CheckErr(o.Complete(f, args))
-			cmdutil.CheckErr(o.Validate())
 			cmdutil.CheckErr(o.Run())
 		},
 	}
@@ -127,6 +126,10 @@ func NewCmdDescribeRollout(f cmdutil.Factory, streams genericclioptions.IOStream
 func (o *DescribeRolloutOptions) Complete(f cmdutil.Factory, args []string) error {
 	var err error
 
+	if len(args) == 0 {
+		return fmt.Errorf("required rollout name not specified")
+	}
+
 	o.Resources = args
 	o.Namespace, o.EnforceNamespace, err = f.ToRawKubeConfigLoader().Namespace()
 
@@ -157,13 +160,6 @@ func (o *DescribeRolloutOptions) Complete(f cmdutil.Factory, args []string) erro
 	return nil
 }
 
-func (o *DescribeRolloutOptions) Validate() error {
-	if len(o.Resources) == 0 {
-		return fmt.Errorf("required rollout name is not specified")
-	}
-	return nil
-}
-
 func (o *DescribeRolloutOptions) Run() error {
 	rolloutName := o.Resources[0]
 
@@ -334,12 +330,17 @@ func (o *DescribeRolloutOptions) GetResources(rollout *rolloutsapi.Rollout) (*Wo
 		labelSelectorParam = "controller-revision-hash"
 	}
 
+	SelectorParam := rollout.Status.CanaryStatus.PodTemplateHash
+	if SelectorParam == "" {
+		SelectorParam = rollout.Status.CanaryStatus.StableRevision
+	}
+
 	// Fetch pods
 	r2 := o.Builder().
 		WithScheme(internalapi.GetScheme(), scheme.Scheme.PrioritizedVersionsAllGroups()...).
 		NamespaceParam(o.Namespace).DefaultNamespace().
 		ResourceTypes("pods").
-		LabelSelectorParam(fmt.Sprintf("%s=%s", labelSelectorParam, rollout.Status.CanaryStatus.PodTemplateHash)).
+		LabelSelectorParam(fmt.Sprintf("%s=%s", labelSelectorParam, SelectorParam)).
 		Latest().
 		Flatten().
 		Do()