| /* |
| * Copyright 2017-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.grpc.api; |
| |
| import com.google.common.annotations.Beta; |
| import io.grpc.ManagedChannel; |
| import io.grpc.stub.StreamObserver; |
| |
| import java.util.Optional; |
| |
| /** |
| * Implementation to add or remove an observer to the managed channel. |
| * |
| */ |
| @Beta |
| public interface GrpcObserverHandler { |
| /** |
| * The implementation of this method adds an |
| * observer on a stub generated on the specific channel. |
| * This method will be called by the gRPC controller. |
| * |
| * @param channel the channel from which to derive the stub. |
| */ |
| void bindObserver(ManagedChannel channel); |
| |
| /** |
| * The implementation of this method returns the request stream |
| * observer, if any, on a stub generated on the specific channel. |
| * |
| * @return the observer on the stub, empty if observer is server-side unidirectional. |
| */ |
| Optional<StreamObserver> requestStreamObserver(); |
| |
| /** |
| * The implementation of this method removes an |
| * observer on a stub generated on the specific channel. |
| * This method will be called by the gRPC controller. |
| */ |
| void removeObserver(); |
| } |