content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.apache.bifromq.basecluster.memberlist;
  
  import io.reactivex.rxjava3.core.Observable;
  import java.util.Map;
  import java.util.Set;
  import java.util.concurrent.CompletableFuture;
  import org.apache.bifromq.basecluster.memberlist.agent.IAgent;
  import org.apache.bifromq.basecluster.membership.proto.HostEndpoint;
  import org.apache.bifromq.basecluster.membership.proto.HostMember;
  
  /**
   * The interface of host member list service.
   */
  public interface IHostMemberList {
      /**
       * The member from local.
       *
       * @return the member object
       */
      HostMember local();
  
      /**
       * If the given endpoint is considered a zombie(The dead endpoint used to live in the local host).
       *
       * @param endpoint the endpoint
       * @return true if the given endpoint is considered a zombie.
       */
      boolean isZombie(HostEndpoint endpoint);
  
      /**
       * Quit local host from the member list, after quit the memberlist instance should never be used.
       */
      CompletableFuture<Void> stop();
  
      /**
       * The hot observable about members.
       *
       * @return the hot observable about members
       */
      Observable<Map<HostEndpoint, Integer>> members();
  
      /**
       * Host the provided agent in local host. If the agent is already hosted, nothing will happen, otherwise other hosts
       * which are residing same agent will get notified.
       *
       * @param agentId the agent id
       */
      IAgent host(String agentId);
  
      /**
       * Stop hosting the agent. If the agent is not a resident, nothing will happen. The agent object is not expected to
       * be used after calling this method.
       *
       * @param agentId the agent id
       */
      CompletableFuture<Void> stopHosting(String agentId);
  
      /**
       * The observable of agents landscape.
       *
       * @return the observable
       */
      Observable<Map<HostEndpoint, Set<String>>> landscape();
  
      /**
       * Emits a signal whenever the local member actively refutes a suspicion of being dead.
       * Each emission carries the timestamp (in millis) when the refutation occurred.
       *
       * @return an observable stream of refutation timestamps
       */
      Observable<Long> refuteSignal();
  }
  