Fission failed to list resources if namespace flag is not provided (#2585)

* use default namespace if no namespace is available
* remove the current-context namespace from push_pr GitHub workflow

.github/workflows/push_pr.yaml

@@ -69,7 +69,6 @@ jobs:
           kubectl get nodes
           sudo apt-get install -y apache2-utils
           kubectl config use-context kind-kind
-          kubectl config set-context --current --namespace=default
           kubectl config view
 
       - name: Helm chart lint

pkg/fission-cli/util/util.go

@@ -166,14 +166,13 @@ func GetKubernetesNamespace(kubeContext string) (currentNS string, err error) {
 		return "", err
 	}
 
-	config1, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
+	namespace, _, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
-		loadingRules, &clientcmd.ConfigOverrides{CurrentContext: kubeContext}).RawConfig()
+		loadingRules, &clientcmd.ConfigOverrides{CurrentContext: kubeContext}).Namespace()
 	if err != nil {
 		return "", errors.Wrap(err, "Failed to build Kubernetes config")
 	}
-	currentNS = config1.Contexts[config1.CurrentContext].Namespace
 
-	return currentNS, nil
+	return namespace, nil
 }
 
 // given a list of functions, this checks if the functions actually exist on the cluster
@@ -508,9 +507,6 @@ func GetResourceNamespace(input cli.Input, deprecatedFlag string) (namespace, cu
 				return namespace, currentNS, err
 			}
 		}
-		if currentNS == "" {
-			return namespace, currentNS, errors.Errorf("either set current-context or provide namespace with --namespace flag")
-		}
 	}
 
 	console.Verbose(2, "Namespace for resource %s ", currentNS)