add namespace param for fn and env (#2556)

This PR moves fission CLI as closer as possible to kubectl command behaviour.  We have improved namespace handling behaviour across CLI.

* add namespace param for fn and env
* use common fn for ns check
* update validation
* default namespace for httpTrigger, env and package, config and triggers
* use default ns
* add namespace filter to spec
* add forceNamespace flag
* set current namespace
* add default namespace in config
* add namespace specific destroy
* add all namespace in the list of resources
* add namespace as global tag
* use %s instead of %v
* add test cases for namespace
* use ns in get all functions

pkg/fission-cli/cmd/kubewatch/create.go

@@ -60,8 +60,12 @@ func (opts *CreateSubCommand) complete(input cli.Input) error {
 		watchName = id.String()
 	}
 	fnName := input.String(flagkey.KwFnName)
-	fnNamespace := input.String(flagkey.NamespaceFunction)
-	namespace := input.String(flagkey.KwNamespace)
+
+	_, namespace, err := util.GetResourceNamespace(input, flagkey.KwNamespace)
+	if err != nil {
+		return errors.Wrap(err, "error in listing function ")
+	}
+
 	objType := input.String(flagkey.KwObjType)
 
 	if input.Bool(flagkey.SpecSave) {
@@ -75,7 +79,7 @@ func (opts *CreateSubCommand) complete(input cli.Input) error {
 		exists, err := fr.ExistsInSpecs(fv1.Function{
 			ObjectMeta: metav1.ObjectMeta{
 				Name:      fnName,
-				Namespace: fnNamespace,
+				Namespace: namespace,
 			},
 		})
 		if err != nil {
@@ -90,7 +94,7 @@ func (opts *CreateSubCommand) complete(input cli.Input) error {
 	opts.watcher = &fv1.KubernetesWatchTrigger{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      watchName,
-			Namespace: fnNamespace,
+			Namespace: namespace,
 		},
 		Spec: fv1.KubernetesWatchTriggerSpec{
 			Namespace: namespace,