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 (pdpStateChangeMsg.appliesTo(pdpStatusContext.getName(), pdpStatusContext.getPdpGroup(),
  55                 pdpStatusContext.getPdpSubgroup())) {
  56             switch (pdpStateChangeMsg.getState()) {
  57                 case PASSIVE:
  58                     pdpResponseDetails = handlePassiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
  59                     break;
  60                 case ACTIVE:
  61                     pdpResponseDetails = handleActiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
  62                     break;
  63                 default:
  64                     break;
  65             }
  66             final PdpStatus pdpStatus = pdpMessageHandler.createPdpStatusFromContext();
  67             pdpStatus.setResponse(pdpResponseDetails);
  68             pdpStatus.setDescription("Pdp status response message for PdpStateChange");
  69             pdpStatusPublisher.send(pdpStatus);
  70         }
  71     }
  72
  73     /**
  74      * Method to handle when the new state from pap is active.
  75      *
  76      * @param pdpStateChangeMsg
  77      * @param pdpStatusContext
  78      * @param pdpMessageHandler
  79      * @return pdpResponseDetails
  80      */
  81     private PdpResponseDetails handleActiveState(final PdpStateChange pdpStateChangeMsg,
  82             final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
  83         PdpResponseDetails pdpResponseDetails = null;
  84         if (pdpStatusContext.getState().equals(PdpState.ACTIVE)) {
  85             pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
  86                     PdpResponseStatus.SUCCESS, "Pdp already in active state");
  87         } else {
  88             final List<ToscaPolicy> policies = Registry.get(ApexStarterConstants.REG_APEX_TOSCA_POLICY_LIST);
  89             if (policies.isEmpty()) {
  90                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
  91                         PdpResponseStatus.SUCCESS, "No policies found. Apex engine not running.");
  92             } else {
  93                 try {
  94                     // assumed that the apex policies list contains only one entry.
  95                     final ApexEngineHandler apexEngineHandler =
  96                             new ApexEngineHandler((String) policies.get(0).getProperties().get("content"));
  97                     Registry.registerOrReplace(ApexStarterConstants.REG_APEX_ENGINE_HANDLER, apexEngineHandler);
  98                     pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
  99                             PdpResponseStatus.SUCCESS, "Apex engine started. State changed to active.");
 100                     pdpStatusContext.setState(PdpState.ACTIVE);
 101                 } catch (final ApexStarterException e) {
 102                     pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 103                             PdpResponseStatus.FAIL, "Apex engine service running failed. " + e.getMessage());
 104                 }
 105             }
 106         }
 107         return pdpResponseDetails;
 108     }
 109
 110     /**
 111      * Method to handle when the new state from pap is passive.
 112      *
 113      * @param pdpStateChangeMsg
 114      * @param pdpStatusContext
 115      * @param pdpMessageHandler
 116      * @return pdpResponseDetails
 117      */
 118     private PdpResponseDetails handlePassiveState(final PdpStateChange pdpStateChangeMsg,
 119             final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
 120         PdpResponseDetails pdpResponseDetails = null;
 121         if (pdpStatusContext.getState().equals(PdpState.PASSIVE)) {
 122             pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 123                     PdpResponseStatus.SUCCESS, "Pdp already in passive state");
 124         } else {
 125             final ApexEngineHandler apexEngineHandler = Registry.get(ApexStarterConstants.REG_APEX_ENGINE_HANDLER);
 126             try {
 127                 apexEngineHandler.shutdown();
 128                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 129                         PdpResponseStatus.SUCCESS, "Apex pdp state changed from Active to Passive.");
 130                 pdpStatusContext.setState(PdpState.PASSIVE);
 131             } catch (final Exception e) {
 132                 pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
 133                         PdpResponseStatus.FAIL,
 134                         "Stopping apex engine failed. State cannot be changed to Passive." + e.getMessage());
 135             }
 136         }
 137         return pdpResponseDetails;
 138     }
 139 }