1 files changed, 125 insertions, 0 deletions
diff --git a/models-sim/policy-models-sim-pdp/src/main/java/org/onap/policy/models/sim/pdp/handler/PdpStateChangeMessageHandler.java b/models-sim/policy-models-sim-pdp/src/main/java/org/onap/policy/models/sim/pdp/handler/PdpStateChangeMessageHandler.java
new file mode 100644
index 000000000..ec1fa25a3
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+++ b/models-sim/policy-models-sim-pdp/src/main/java/org/onap/policy/models/sim/pdp/handler/PdpStateChangeMessageHandler.java
@@ -0,0 +1,125 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2019 Nordix 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.models.sim.pdp.handler;
+
+import java.util.List;
+
+import org.onap.policy.common.utils.services.Registry;
+import org.onap.policy.models.pdp.concepts.PdpResponseDetails;
+import org.onap.policy.models.pdp.concepts.PdpStateChange;
+import org.onap.policy.models.pdp.concepts.PdpStatus;
+import org.onap.policy.models.pdp.enums.PdpResponseStatus;
+import org.onap.policy.models.pdp.enums.PdpState;
+import org.onap.policy.models.sim.pdp.PdpSimulatorConstants;
+import org.onap.policy.models.sim.pdp.comm.PdpStatusPublisher;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicy;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class supports the handling of pdp state change messages.
+ *
+ * @author Ajith Sreekumar (ajith.sreekumar@est.tech)
+ */
+public class PdpStateChangeMessageHandler {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(PdpStateChangeMessageHandler.class);
+
+    /**
+     * Method which handles a pdp state change event from PAP.
+     *
+     * @param pdpStateChangeMsg pdp state change message
+     */
+    public void handlePdpStateChangeEvent(final PdpStateChange pdpStateChangeMsg) {
+        final PdpStatus pdpStatusContext = Registry.get(PdpSimulatorConstants.REG_PDP_STATUS_OBJECT, PdpStatus.class);
+        final PdpStatusPublisher pdpStatusPublisher = Registry.get(PdpSimulatorConstants.REG_PDP_STATUS_PUBLISHER);
+        final PdpMessageHandler pdpMessageHandler = new PdpMessageHandler();
+        PdpResponseDetails pdpResponseDetails = null;
+        if (pdpStateChangeMsg.appliesTo(pdpStatusContext.getName(), pdpStatusContext.getPdpGroup(),
+                pdpStatusContext.getPdpSubgroup())) {
+            switch (pdpStateChangeMsg.getState()) {
+                case PASSIVE:
+                    pdpResponseDetails = handlePassiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
+                    break;
+                case ACTIVE:
+                    pdpResponseDetails = handleActiveState(pdpStateChangeMsg, pdpStatusContext, pdpMessageHandler);
+                    break;
+                default:
+                    break;
+            }
+            final PdpStatus pdpStatus = pdpMessageHandler.createPdpStatusFromContext();
+            pdpStatus.setResponse(pdpResponseDetails);
+            pdpStatus.setDescription("Pdp status response message for PdpStateChange");
+            pdpStatusPublisher.send(pdpStatus);
+        }
+    }
+
+    /**
+     * Method to handle when the new state from pap is active.
+     *
+     * @param pdpStateChangeMsg pdp state change message
+     * @param pdpStatusContext pdp status object in memory
+     * @param pdpMessageHandler the pdp message handler
+     * @return pdpResponseDetails pdp response
+     */
+    private PdpResponseDetails handleActiveState(final PdpStateChange pdpStateChangeMsg,
+            final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
+        PdpResponseDetails pdpResponseDetails = null;
+        if (pdpStatusContext.getState().equals(PdpState.ACTIVE)) {
+            pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
+                    PdpResponseStatus.SUCCESS, "Pdp already in active state");
+        } else {
+            final List<ToscaPolicy> policies = Registry.get(PdpSimulatorConstants.REG_PDP_TOSCA_POLICY_LIST);
+            if (policies.isEmpty()) {
+                pdpStatusContext.setState(PdpState.ACTIVE);
+                pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
+                        PdpResponseStatus.SUCCESS, "State changed to active. No policies found.");
+            } else {
+                pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
+                        PdpResponseStatus.SUCCESS, "Pdp started. State changed to active.");
+                pdpStatusContext.setState(PdpState.ACTIVE);
+            }
+        }
+        return pdpResponseDetails;
+    }
+
+    /**
+     * Method to handle when the new state from pap is passive.
+     *
+     * @param pdpStateChangeMsg pdp state change message
+     * @param pdpStatusContext pdp status object in memory
+     * @param pdpMessageHandler the pdp message handler
+     * @return pdpResponseDetails pdp response
+     */
+    private PdpResponseDetails handlePassiveState(final PdpStateChange pdpStateChangeMsg,
+            final PdpStatus pdpStatusContext, final PdpMessageHandler pdpMessageHandler) {
+        PdpResponseDetails pdpResponseDetails = null;
+        if (pdpStatusContext.getState().equals(PdpState.PASSIVE)) {
+            pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
+                    PdpResponseStatus.SUCCESS, "Pdp already in passive state");
+        } else {
+            pdpResponseDetails = pdpMessageHandler.createPdpResonseDetails(pdpStateChangeMsg.getRequestId(),
+                    PdpResponseStatus.SUCCESS, "Pdp state changed from Active to Passive.");
+            pdpStatusContext.setState(PdpState.PASSIVE);
+        }
+        return pdpResponseDetails;
+    }
+}