gerrit.onap Code Review - policy/apex-pdp.git/blob

   1 /*-
   2  * ============LICENSE_START=======================================================
   3  *  Copyright (C) 2019 Nordix Foundation.
   4  * ================================================================================
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *      http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  *
  17  * SPDX-License-Identifier: Apache-2.0
  18  * ============LICENSE_END=========================================================
  19  */
  20
  21 package org.onap.policy.apex.starter.handler;
  22
  23 import java.util.List;
  24
  25 import org.onap.policy.apex.starter.ApexStarterConstants;
  26 import org.onap.policy.apex.starter.comm.PdpStatusPublisher;
  27 import org.onap.policy.apex.starter.engine.ApexEngineHandler;
  28 import org.onap.policy.apex.starter.exception.ApexStarterException;
  29 import org.onap.policy.common.utils.services.Registry;
  30 import org.onap.policy.models.pdp.concepts.PdpResponseDetails;
  31 import org.onap.policy.models.pdp.concepts.PdpStateChange;
  32 import org.onap.policy.models.pdp.concepts.PdpStatus;
  33 import org.onap.policy.models.pdp.enums.PdpResponseStatus;
  34 import org.onap.policy.models.pdp.enums.PdpState;
  35 import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicy;
  36
  37 /**
  38  * This class supports the handling of pdp state change messages.
  39  *
  40  * @author Ajith Sreekumar (ajith.sreekumar@est.tech)
  41  */
  42 public class PdpStateChangeMessageHandler {
  43
  44     /**
  45      * Method which handles a pdp state change event from PAP.
  46      *
  47      * @param pdpStateChangeMsg pdp state change message
  48      */
  49     public void handlePdpStateChangeEvent(final PdpStateChange pdpStateChangeMsg) {
  50         final PdpStatus pdpStatusContext = Registry.get(ApexStarterConstants.REG_PDP_STATUS_OBJECT, PdpStatus.class);
  51         final PdpStatusPublisher pdpStatusPublisher = Registry.get(ApexStarterConstants.REG_PDP_STATUS_PUBLISHER);
  52         final PdpMessageHandler pdpMessageHandler = new PdpMessageHandler();
  53         PdpResponseDetails pdpResponseDetails = null;
  54         if (isMessageRelevant(pdpStateChangeMsg, pdpStatusContext)) {
  55             switch (pdpStateChangeMsg.getState()) {
  56                 case TERMINATED:
  57                     pdpResponseDetails = handleTerminatedState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
  58                     break;
  59                 case PASSIVE:
  60                     pdpResponseDetails = handlePassiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
  61                     break;
  62                 case ACTIVE:
  63                     pdpResponseDetails = handleActiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
  64                     break;
  65                 default:
  66                     break;
  67             }
  68             final PdpStatus pdpStatus = pdpMessageHandler.createPdpStatusFromContext();
  69             pdpStatus.setResponse(pdpResponseDetails);
  70             pdpStatusPublisher.send(pdpStatus);
  71         }
  72     }
  73
  74     /**
  75      * Check if the pdp state change message is meant for this pdp.
  76      *
  77      * @param pdpStateChangeMsg
  78      * @param pdpStatusContext
  79      * @return boolean value if relevant or not
  80      */
  81     private boolean isMessageRelevant(final PdpStateChange pdpStateChangeMsg, final PdpStatus pdpStatusContext) {
  82         return pdpStatusContext.getName().equals(pdpStateChangeMsg.getName()) || (null == pdpStateChangeMsg.getName()
  83                 && pdpStateChangeMsg.getPdpGroup().equals(pdpStatusContext.getPdpGroup())
  84                 && pdpStateChangeMsg.getPdpSubgroup().equals(pdpStatusContext.getPdpSubgroup()));
  85     }
  86
  87     /**
  88      * Method to handle when the new state from pap is active.
  89      *
  90      * @param pdpStateChangeMsg
  91      * @param pdpStatusContext
  92      * @param pdpMessageHandler
  93      * @return pdpResponseDetails
  94      */
  95     private PdpResponseDetails handleActiveState(final PdpStateChange pdpStateChangeMsg,
  96             final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
  97         PdpResponseDetails pdpResponseDetails = null;
  98         if (pdpStatusContext.getState().equals(PdpState.ACTIVE)) {
  99             pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 100                     PdpResponseStatus.SUCCESS, "Pdp already in active state");
 101         } else {
 102             final List<ToscaPolicy> policies = Registry.get(ApexStarterConstants.REG_APEX_TOSCA_POLICY_LIST);
 103             if (policies.isEmpty()) {
 104                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 105                         PdpResponseStatus.SUCCESS, "No policies found. Apex engine not running.");
 106             } else {
 107                 try {
 108                     // assumed that the apex policies list contains only one entry.
 109                     final ApexEngineHandler apexEngineHandler =
 110                             new ApexEngineHandler((String) policies.get(0).getProperties().get("content"));
 111                     Registry.register(ApexStarterConstants.REG_APEX_ENGINE_HANDLER, apexEngineHandler);
 112                     pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 113                             PdpResponseStatus.SUCCESS, "Apex engine started. State changed to active.");
 114                     pdpStatusContext.setState(PdpState.ACTIVE);
 115                 } catch (final ApexStarterException e) {
 116                     pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 117                             PdpResponseStatus.FAIL, "Apex engine service running failed. " + e.getMessage());
 118                 }
 119             }
 120         }
 121         return pdpResponseDetails;
 122     }
 123
 124     /**
 125      * Method to handle when the new state from pap is passive.
 126      *
 127      * @param pdpStateChangeMsg
 128      * @param pdpStatusContext
 129      * @param pdpMessageHandler
 130      * @return pdpResponseDetails
 131      */
 132     private PdpResponseDetails handlePassiveState(final PdpStateChange pdpStateChangeMsg,
 133             final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
 134         PdpResponseDetails pdpResponseDetails = null;
 135         if (pdpStatusContext.getState().equals(PdpState.PASSIVE)) {
 136             pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 137                     PdpResponseStatus.SUCCESS, "Pdp already in passive state");
 138         } else {
 139             final ApexEngineHandler apexEngineHandler = Registry.get(ApexStarterConstants.REG_APEX_ENGINE_HANDLER);
 140             try {
 141                 apexEngineHandler.shutdown();
 142                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 143                         PdpResponseStatus.SUCCESS, "Apex pdp state changed from Active to Passive.");
 144                 pdpStatusContext.setState(PdpState.PASSIVE);
 145             } catch (final Exception e) {
 146                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 147                         PdpResponseStatus.FAIL,
 148                         "Stopping apex engine failed. State cannot be changed to Passive." + e.getMessage());
 149             }
 150         }
 151         return pdpResponseDetails;
 152     }
 153
 154     /**
 155      * Method to handle when the new state from pap is terminated.
 156      *
 157      * @param pdpStateChangeMsg
 158      * @param pdpStatusPublisher
 159      * @param pdpMessageHandler
 160      * @return pdpResponseDetails
 161      */
 162     private PdpResponseDetails handleTerminatedState(final PdpStateChange pdpStateChangeMsg,
 163             final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
 164
 165         PdpResponseDetails pdpResponseDetails;
 166         if (pdpStatusContext.getState().equals(PdpState.ACTIVE)) {
 167             final ApexEngineHandler apexEngineHandler = Registry.get(ApexStarterConstants.REG_APEX_ENGINE_HANDLER);
 168             try {
 169                 apexEngineHandler.shutdown();
 170                 pdpStatusContext.setState(PdpState.PASSIVE);
 171                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 172                         PdpResponseStatus.SUCCESS, "Apex Engine stopped. State changed to passive.");
 173             } catch (final Exception e) {
 174                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 175                         PdpResponseStatus.FAIL,
 176                         "Stopping apex engine failed. State cannot be changed." + e.getMessage());
 177             }
 178         } else {
 179             pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 180                     PdpResponseStatus.SUCCESS, "Pdp already in passive state");
 181         }
 182         return pdpResponseDetails;
 183
 184     }
 185 }