[ONOS-7683] Add a set of empty telemetry config managers with intfs

Change-Id: Ib3dca1f1aa8f69c121c295af3c77d9c50bb032d4
diff --git a/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryAdminService.java b/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryAdminService.java
new file mode 100644
index 0000000..16b921b
--- /dev/null
+++ b/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryAdminService.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2018-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.openstacktelemetry.api;
+
+import org.onosproject.openstacktelemetry.api.config.TelemetryConfig;
+
+/**
+ * Admin service API for publishing openstack telemetry.
+ */
+public interface TelemetryAdminService {
+
+    /**
+     * Prepares and launches the telemetry producer.
+     *
+     * @param config telemetry server config
+     */
+    void start(TelemetryConfig config);
+
+    /**
+     * Terminates the telemetry producer.
+     */
+    void stop();
+
+    /**
+     * Restarts the telemetry producer.
+     *
+     * @param config telemetry server config
+     */
+    void restart(TelemetryConfig config);
+}