Add a set of interfaces for k8s pod, service, endpoint

Change-Id: Ie67c5d1a0678bdd651dac24363ab3feab5098919
diff --git a/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sEndpointsService.java b/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sEndpointsService.java
new file mode 100644
index 0000000..8f90269
--- /dev/null
+++ b/apps/k8s-networking/api/src/main/java/org/onosproject/k8snetworking/api/K8sEndpointsService.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2019-present Open Networking Foundation
+ *
+ * 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 org.onosproject.k8snetworking.api;
+
+import io.fabric8.kubernetes.api.model.Endpoints;
+import org.onosproject.event.ListenerService;
+
+import java.util.Set;
+
+/**
+ * Service for interacting with the inventory of kubernetes endpoints.
+ */
+public interface K8sEndpointsService
+        extends ListenerService<K8sEndpointsEvent, K8sEndpointsListener> {
+
+    /**
+     * Returns the kubernetes endpoints with the supplied endpoints UID.
+     *
+     * @param uid endpoint UID
+     * @return kubernetes endpoints
+     */
+    Endpoints endpoints(String uid);
+
+    /**
+     * Returns all kubernetes endpoints registered.
+     *
+     * @return set of kubernetes endpoints
+     */
+    Set<Endpoints> endpointses();
+}