Fix issue:[#178](https://github.com/DirectXMan12/k8s-prometheus-adapter/issues/178)

Fix namespaced bug of node resource, node resource should be a
non-namespaced resource as the resource namespace.

By doing this fix, node resouce can be accessed as expected, as the issue explains.

Closes issue:[#178](https://github.com/DirectXMan12/k8s-prometheus-adapter/issues/178)

pkg/custom-provider/metric_namer.go

@@ -14,6 +14,7 @@ import (
 )
 
 var nsGroupResource = schema.GroupResource{Resource: "namespaces"}
+var nodeGroupResource = schema.GroupResource{Resource: "nodes"}
 var groupNameSanitizer = strings.NewReplacer(".", "_", "-", "_")
 
 // MetricNamer knows how to convert Prometheus series names and label names to

pkg/custom-provider/series_registry.go

@@ -99,7 +99,7 @@ func (r *basicSeriesRegistry) SetSeries(newSeriesSlices [][]prom.Series, namers
 				}
 
 				// namespace metrics aren't counted as namespaced
-				if resource == nsGroupResource {
+				if resource == nsGroupResource || resource == nodeGroupResource {
 					info.Namespaced = false
 				}