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 com.cloud.ha;
  
  import java.util.List;
  
  import javax.inject.Inject;
  
  import org.apache.cloudstack.ha.HAManager;
  
  import com.cloud.agent.AgentManager;
  import com.cloud.agent.api.Answer;
  import com.cloud.agent.api.CheckOnHostCommand;
  import com.cloud.agent.api.CheckVirtualMachineAnswer;
  import com.cloud.agent.api.CheckVirtualMachineCommand;
  import com.cloud.exception.AgentUnavailableException;
  import com.cloud.exception.OperationTimedoutException;
  import com.cloud.host.Host;
  import com.cloud.host.HostVO;
  import com.cloud.host.Status;
  import com.cloud.hypervisor.Hypervisor;
  import com.cloud.hypervisor.Hypervisor.HypervisorType;
  import com.cloud.resource.ResourceManager;
  import com.cloud.simulator.dao.MockConfigurationDao;
  import com.cloud.utils.component.AdapterBase;
  import com.cloud.vm.VirtualMachine;
  import com.cloud.vm.VirtualMachine.PowerState;
  
  public class SimulatorInvestigator extends AdapterBase implements Investigator {
      @Inject
      AgentManager _agentMgr;
      @Inject
      ResourceManager _resourceMgr;
      @Inject
      MockConfigurationDao _mockConfigDao;
      @Inject
      private HAManager haManager;
  
      protected SimulatorInvestigator() {
      }
  
      @Override
      public Status isAgentAlive(Host agent) {
          if (agent.getHypervisorType() != HypervisorType.Simulator) {
              return null;
          }
  
          if (haManager.isHAEligible(agent)) {
              return haManager.getHostStatus(agent);
          }
  
          CheckOnHostCommand cmd = new CheckOnHostCommand(agent);
          List<HostVO> neighbors = _resourceMgr.listHostsInClusterByStatus(agent.getClusterId(), Status.Up);
          for (HostVO neighbor : neighbors) {
              if (neighbor.getId() == agent.getId() || neighbor.getHypervisorType() != Hypervisor.HypervisorType.Simulator) {
                  continue;
              }
              try {
                  Answer answer = _agentMgr.easySend(neighbor.getId(), cmd);
                  if (answer != null) {
                      return answer.getResult() ? Status.Up : Status.Down;
                  }
              } catch (Exception e) {
                  logger.debug(String.format("Failed to send command to host: %s", neighbor));
              }
          }
  
          return null;
      }
  
      @Override
      public boolean isVmAlive(VirtualMachine vm, Host host) throws UnknownVM {
          if (haManager.isHAEligible(host)) {
              return haManager.isVMAliveOnHost(host);
          }
          CheckVirtualMachineCommand cmd = new CheckVirtualMachineCommand(vm.getInstanceName());
          try {
              Answer answer = _agentMgr.send(vm.getHostId(), cmd);
              if (!answer.getResult()) {
                  logger.debug("Unable to get vm state on " + vm.toString());
                  throw new UnknownVM();
              }
              CheckVirtualMachineAnswer cvmAnswer = (CheckVirtualMachineAnswer)answer;
              logger.debug("Agent responded with state " + cvmAnswer.getState().toString());
              return cvmAnswer.getState() == PowerState.PowerOn;
          } catch (AgentUnavailableException e) {
              logger.debug("Unable to reach the agent for " + vm.toString() + ": " + e.getMessage());
              throw new UnknownVM();
          } catch (OperationTimedoutException e) {
              logger.debug("Operation timed out for " + vm.toString() + ": " + e.getMessage());
              throw new UnknownVM();
          }
      }
  }
  