Add openshift detector

Signed-off-by: Tamal Saha <tamal@appscode.com>

cluster/lib.go

@@ -133,9 +133,9 @@ func DetectClusterManager(kc client.Client) kmapi.ClusterManager {
 	if IsRancherManaged(kc.RESTMapper()) {
 		result |= kmapi.ClusterManagerRancher
 	}
-	//if IsRancherManaged(kc.RESTMapper()) {
-	//	result |= kmapi.ClusterManagerRancher
-	//}
+	if IsOpenShiftManaged(kc.RESTMapper()) {
+		result |= kmapi.ClusterManagerOpenShift
+	}
 	if MustIsVirtualCluster(kc) {
 		result |= kmapi.ClusterManagerVirtualCluster
 	}

cluster/openshift.go

@@ -0,0 +1,32 @@
+/*
+Copyright AppsCode Inc. and Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cluster
+
+import (
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+)
+
+func IsOpenShiftManaged(mapper meta.RESTMapper) bool {
+	if _, err := mapper.RESTMappings(schema.GroupKind{
+		Group: "project.openshift.io",
+		Kind:  "Project",
+	}); err == nil {
+		return true
+	}
+	return false
+}