Delete Subscription method

Issue-ID: CPS-2253
Change-Id: I30768dc431e13d0bac0dcc7b9b16cb0854f06702
Signed-off-by: emaclee <lee.anjella.macabuhay@est.tech>

12 files changed, 273 insertions, 54 deletions

diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandler.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandler.java
index c5052f1405..b5ab7f6525 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandler.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandler.java
@@ -50,7 +50,7 @@ public class DmiCacheHandler {
     private final InventoryPersistence inventoryPersistence;
 
     /**
-     * Adds new subscription to the subscription cache.
+     * Adds subscription to the subscription cache.
      *
      * @param subscriptionId    subscription id
      * @param predicates        subscription request predicates
@@ -60,6 +60,18 @@ public class DmiCacheHandler {
     }
 
     /**
+     * Adds subscription to the subscription cache.
+     *
+     * @param subscriptionId subscription id
+     * @param dmiCmSubscriptionDetailsPerDmi map of dmi cm notification subscription details per dmi
+     */
+    public void add(final String subscriptionId,
+                    final Map<String, DmiCmSubscriptionDetails>
+                            dmiCmSubscriptionDetailsPerDmi) {
+        cmNotificationSubscriptionCache.put(subscriptionId, dmiCmSubscriptionDetailsPerDmi);
+    }
+
+    /**
      * Get cm notification subscription cache entry via subscription id.
      *
      * @param subscriptionId    subscription id
@@ -122,8 +134,8 @@ public class DmiCacheHandler {
      * @param status            String of status
      *
      */
-    public void updateDmiSubscriptionStatusPerDmi(final String subscriptionId, final String dmiServiceName,
-            final CmSubscriptionStatus status) {
+    public void updateDmiSubscriptionStatus(final String subscriptionId, final String dmiServiceName,
+                                            final CmSubscriptionStatus status) {
         final Map<String, DmiCmSubscriptionDetails> dmiSubscriptionsPerDmi =
                 cmNotificationSubscriptionCache.get(subscriptionId);
         dmiSubscriptionsPerDmi.get(dmiServiceName).setCmSubscriptionStatus(status);
@@ -162,7 +174,7 @@ public class DmiCacheHandler {
      * @param dmiServiceName    String of dmiServiceName
      *
      */
-    public void removeFromDatabasePerDmi(final String subscriptionId, final String dmiServiceName) {
+    public void removeFromDatabase(final String subscriptionId, final String dmiServiceName) {
         final List<DmiCmSubscriptionPredicate> dmiCmSubscriptionPredicates =
                 cmNotificationSubscriptionCache.get(subscriptionId).get(dmiServiceName)
                         .getDmiCmSubscriptionPredicates();
@@ -210,6 +222,6 @@ public class DmiCacheHandler {
 
     private boolean isAcceptedOrRejected(final DmiCmSubscriptionDetails dmiCmSubscription) {
         return dmiCmSubscription.getCmSubscriptionStatus().toString().equals("ACCEPTED")
-                       || dmiCmSubscription.getCmSubscriptionStatus().toString().equals("REJECTED");
+                || dmiCmSubscription.getCmSubscriptionStatus().toString().equals("REJECTED");
     }
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumer.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumer.java
index 20ccf528ed..20c7c7b13d 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumer.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumer.java
@@ -80,7 +80,7 @@ public class DmiOutEventConsumer {
                 dmiCacheHandler.persistIntoDatabasePerDmi(subscriptionId, dmiPluginName);
             }
             if (eventType.equals("subscriptionDeleteResponse")) {
-                dmiCacheHandler.removeFromDatabasePerDmi(subscriptionId, dmiPluginName);
+                dmiCacheHandler.removeFromDatabase(subscriptionId, dmiPluginName);
             }
             handleEventsStatusPerDmi(subscriptionId, eventType);
         }
@@ -96,7 +96,7 @@ public class DmiOutEventConsumer {
 
     private void handleCacheStatusPerDmi(final String subscriptionId, final String dmiPluginName,
             final CmSubscriptionStatus cmSubscriptionStatus) {
-        dmiCacheHandler.updateDmiSubscriptionStatusPerDmi(subscriptionId, dmiPluginName,
+        dmiCacheHandler.updateDmiSubscriptionStatus(subscriptionId, dmiPluginName,
                 cmSubscriptionStatus);
     }
 
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/models/DmiCmSubscriptionTuple.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/models/DmiCmSubscriptionTuple.java
new file mode 100644
index 0000000000..cd4a15af47
--- /dev/null
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/models/DmiCmSubscriptionTuple.java
@@ -0,0 +1,34 @@
+/*
+ *  ============LICENSE_START=======================================================
+ *  Copyright (C) 2024 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.cps.ncmp.impl.cmnotificationsubscription.models;
+
+import java.util.Collection;
+import java.util.Map;
+
+/**
+ * Tuple to be used during for to delete usecase.
+ *
+ * @param lastRemainingSubscriptionsPerDmi   subscriptions that are used by only one subscriber grouped per dmi
+ * @param overlappingSubscriptionsPerDmi     subscriptions that are shared by multiple subscribers grouped per dmi
+ */
+public record DmiCmSubscriptionTuple(Map<String, Collection<DmiCmSubscriptionKey>> lastRemainingSubscriptionsPerDmi,
+                                     Map<String, Collection<DmiCmSubscriptionKey>> overlappingSubscriptionsPerDmi) {
+}
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandler.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandler.java
index 3a9b2066b2..90c5c575e6 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandler.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandler.java
@@ -37,8 +37,7 @@ public interface CmSubscriptionHandler {
      * Process cm notification subscription delete request.
      *
      * @param subscriptionId subscription id
-     * @param predicates subscription predicates
      */
-    void processSubscriptionDeleteRequest(final String subscriptionId, final List<Predicate> predicates);
+    void processSubscriptionDeleteRequest(final String subscriptionId);
 
 }
\ No newline at end of file
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImpl.java
index 9d33d25816..c2c71dbaae 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImpl.java
@@ -21,34 +21,50 @@
 package org.onap.cps.ncmp.impl.cmnotificationsubscription.ncmp;
 
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import lombok.RequiredArgsConstructor;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.cache.DmiCacheHandler;
+import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiCmSubscriptionDetailsPerDmiMapper;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiInEventMapper;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiInEventProducer;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.CmSubscriptionStatus;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.DmiCmSubscriptionDetails;
+import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.DmiCmSubscriptionKey;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.DmiCmSubscriptionPredicate;
+import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.DmiCmSubscriptionTuple;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.utils.CmSubscriptionPersistenceService;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.client_to_ncmp.Predicate;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.ncmp_to_client.NcmpOutEvent;
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.ncmp_to_dmi.DmiInEvent;
+import org.onap.cps.ncmp.impl.inventory.InventoryPersistence;
+import org.onap.cps.spi.model.DataNode;
 import org.springframework.stereotype.Service;
 
 @Service
 @RequiredArgsConstructor
 public class CmSubscriptionHandlerImpl implements CmSubscriptionHandler {
 
+    private static final Pattern SUBSCRIPTION_KEY_FROM_XPATH_PATTERN = Pattern.compile(
+            "^/datastores/datastore\\[@name='([^']*)']/cm-handles/cm-handle\\[@id='([^']*)']/"
+                    + "filters/filter\\[@xpath='(.*)']$");
+
     private final CmSubscriptionPersistenceService cmSubscriptionPersistenceService;
     private final CmSubscriptionComparator cmSubscriptionComparator;
     private final NcmpOutEventMapper ncmpOutEventMapper;
     private final DmiInEventMapper dmiInEventMapper;
+    private final DmiCmSubscriptionDetailsPerDmiMapper dmiCmSubscriptionDetailsPerDmiMapper;
     private final NcmpOutEventProducer ncmpOutEventProducer;
     private final DmiInEventProducer dmiInEventProducer;
     private final DmiCacheHandler dmiCacheHandler;
+    private final InventoryPersistence inventoryPersistence;
 
     @Override
     public void processSubscriptionCreateRequest(final String subscriptionId, final List<Predicate> predicates) {
@@ -62,10 +78,45 @@ public class CmSubscriptionHandlerImpl implements CmSubscriptionHandler {
     }
 
     @Override
-    public void processSubscriptionDeleteRequest(final String subscriptionId, final List<Predicate> predicates) {
-        dmiCacheHandler.add(subscriptionId, predicates);
-        sendSubscriptionDeleteRequestToDmi(subscriptionId);
-        scheduleNcmpOutEventResponse(subscriptionId, "subscriptionDeleteResponse");
+    public void processSubscriptionDeleteRequest(final String subscriptionId) {
+        final Collection<DataNode> subscriptionDataNodes =
+                cmSubscriptionPersistenceService.getAllNodesForSubscriptionId(subscriptionId);
+        final DmiCmSubscriptionTuple dmiCmSubscriptionTuple =
+                getLastRemainingAndOverlappingSubscriptionsPerDmi(subscriptionDataNodes);
+        dmiCacheHandler.add(subscriptionId, mergeDmiCmSubscriptionDetailsPerDmiMaps(dmiCmSubscriptionTuple));
+        if (dmiCmSubscriptionTuple.lastRemainingSubscriptionsPerDmi().isEmpty()) {
+            acceptAndPublishDeleteRequest(subscriptionId);
+        } else {
+            sendSubscriptionDeleteRequestToDmi(subscriptionId,
+                    dmiCmSubscriptionDetailsPerDmiMapper.toDmiCmSubscriptionsPerDmi(
+                            dmiCmSubscriptionTuple.lastRemainingSubscriptionsPerDmi()));
+            scheduleNcmpOutEventResponse(subscriptionId, "subscriptionDeleteResponse");
+        }
+    }
+
+    private Map<String, DmiCmSubscriptionDetails> mergeDmiCmSubscriptionDetailsPerDmiMaps(
+            final DmiCmSubscriptionTuple dmiCmSubscriptionTuple) {
+        final Map<String, DmiCmSubscriptionDetails> lastRemainingDmiSubscriptionsPerDmi =
+                dmiCmSubscriptionDetailsPerDmiMapper.toDmiCmSubscriptionsPerDmi(
+                        dmiCmSubscriptionTuple.lastRemainingSubscriptionsPerDmi());
+        final Map<String, DmiCmSubscriptionDetails> overlappingDmiSubscriptionsPerDmi =
+                dmiCmSubscriptionDetailsPerDmiMapper.toDmiCmSubscriptionsPerDmi(
+                        dmiCmSubscriptionTuple.overlappingSubscriptionsPerDmi());
+        final Map<String, DmiCmSubscriptionDetails> mergedDmiSubscriptionsPerDmi =
+                new HashMap<>(lastRemainingDmiSubscriptionsPerDmi);
+        overlappingDmiSubscriptionsPerDmi.forEach((dmiServiceName, dmiCmSubscriptionDetails) ->
+                mergedDmiSubscriptionsPerDmi.merge(dmiServiceName, dmiCmSubscriptionDetails,
+                        this::mergeDmiCmSubscriptionDetails));
+        return mergedDmiSubscriptionsPerDmi;
+    }
+
+    private DmiCmSubscriptionDetails mergeDmiCmSubscriptionDetails(
+            final DmiCmSubscriptionDetails dmiCmSubscriptionDetails,
+            final DmiCmSubscriptionDetails otherDmiCmSubscriptionDetails) {
+        final List<DmiCmSubscriptionPredicate> mergedDmiCmSubscriptionPredicates =
+                new ArrayList<>(dmiCmSubscriptionDetails.getDmiCmSubscriptionPredicates());
+        mergedDmiCmSubscriptionPredicates.addAll(otherDmiCmSubscriptionDetails.getDmiCmSubscriptionPredicates());
+        return new DmiCmSubscriptionDetails(mergedDmiCmSubscriptionPredicates, CmSubscriptionStatus.PENDING);
     }
 
     private void scheduleNcmpOutEventResponse(final String subscriptionId, final String eventType) {
@@ -81,6 +132,19 @@ public class CmSubscriptionHandlerImpl implements CmSubscriptionHandler {
         ncmpOutEventProducer.publishNcmpOutEvent(subscriptionId, "subscriptionCreateResponse", ncmpOutEvent, false);
     }
 
+    private void acceptAndPublishDeleteRequest(final String subscriptionId) {
+        final Set<String> dmiServiceNames = dmiCacheHandler.get(subscriptionId).keySet();
+        for (final String dmiServiceName : dmiServiceNames) {
+            dmiCacheHandler.updateDmiSubscriptionStatus(subscriptionId, dmiServiceName,
+                    CmSubscriptionStatus.ACCEPTED);
+            dmiCacheHandler.removeFromDatabase(subscriptionId, dmiServiceName);
+        }
+        final NcmpOutEvent ncmpOutEvent = ncmpOutEventMapper.toNcmpOutEvent(subscriptionId,
+                dmiCacheHandler.get(subscriptionId));
+        ncmpOutEventProducer.publishNcmpOutEvent(subscriptionId, "subscriptionDeleteResponse", ncmpOutEvent,
+                false);
+    }
+
     private void handleNewCmSubscription(final String subscriptionId) {
         final Map<String, DmiCmSubscriptionDetails> dmiSubscriptionsPerDmi =
                 dmiCacheHandler.get(subscriptionId);
@@ -98,26 +162,68 @@ public class CmSubscriptionHandlerImpl implements CmSubscriptionHandler {
     }
 
     private void publishDmiInEventPerDmi(final String subscriptionId, final String dmiPluginName,
-            final List<DmiCmSubscriptionPredicate> dmiCmSubscriptionPredicates) {
+                                         final List<DmiCmSubscriptionPredicate> dmiCmSubscriptionPredicates) {
         final DmiInEvent dmiInEvent = dmiInEventMapper.toDmiInEvent(dmiCmSubscriptionPredicates);
         dmiInEventProducer.publishDmiInEvent(subscriptionId, dmiPluginName,
                 "subscriptionCreateRequest", dmiInEvent);
     }
 
     private void acceptAndPublishNcmpOutEventPerDmi(final String subscriptionId, final String dmiPluginName) {
-        dmiCacheHandler.updateDmiSubscriptionStatusPerDmi(subscriptionId, dmiPluginName,
+        dmiCacheHandler.updateDmiSubscriptionStatus(subscriptionId, dmiPluginName,
                 CmSubscriptionStatus.ACCEPTED);
         dmiCacheHandler.persistIntoDatabasePerDmi(subscriptionId, dmiPluginName);
     }
 
-    private void sendSubscriptionDeleteRequestToDmi(final String subscriptionId) {
-        final Map<String, DmiCmSubscriptionDetails> dmiSubscriptionsPerDmi =
-                dmiCacheHandler.get(subscriptionId);
-        dmiSubscriptionsPerDmi.forEach((dmiPluginName, dmiSubscriptionDetails) -> {
-            final DmiInEvent dmiInEvent = dmiInEventMapper.toDmiInEvent(
-                    dmiSubscriptionDetails.getDmiCmSubscriptionPredicates());
-            dmiInEventProducer.publishDmiInEvent(subscriptionId, dmiPluginName,
-                    "subscriptionDeleteRequest", dmiInEvent);
+    private void sendSubscriptionDeleteRequestToDmi(final String subscriptionId,
+                                                    final Map<String, DmiCmSubscriptionDetails>
+                                                            dmiCmSubscriptionsPerDmi) {
+        dmiCmSubscriptionsPerDmi.forEach((dmiPluginName, dmiCmSubscriptionDetails) -> {
+            final DmiInEvent dmiInEvent =
+                    dmiInEventMapper.toDmiInEvent(
+                            dmiCmSubscriptionDetails.getDmiCmSubscriptionPredicates());
+            dmiInEventProducer.publishDmiInEvent(subscriptionId,
+                    dmiPluginName, "subscriptionDeleteRequest", dmiInEvent);
         });
     }
+
+
+    private DmiCmSubscriptionTuple getLastRemainingAndOverlappingSubscriptionsPerDmi(
+            final Collection<DataNode> subscriptionNodes) {
+        final Map<String, Collection<DmiCmSubscriptionKey>> lastRemainingSubscriptionsPerDmi = new HashMap<>();
+        final Map<String, Collection<DmiCmSubscriptionKey>> overlappingSubscriptionsPerDmi = new HashMap<>();
+
+        for (final DataNode subscriptionNode : subscriptionNodes) {
+            final DmiCmSubscriptionKey dmiCmSubscriptionKey = extractCmSubscriptionKey(subscriptionNode.getXpath());
+            final String dmiServiceName = inventoryPersistence.getYangModelCmHandle(
+                    dmiCmSubscriptionKey.cmHandleId()).getDmiServiceName();
+            final List<String> subscribers = (List<String>) subscriptionNode.getLeaves().get("subscriptionIds");
+            populateDmiCmSubscriptionTuple(subscribers, overlappingSubscriptionsPerDmi,
+                    lastRemainingSubscriptionsPerDmi, dmiServiceName, dmiCmSubscriptionKey);
+        }
+        return new DmiCmSubscriptionTuple(lastRemainingSubscriptionsPerDmi, overlappingSubscriptionsPerDmi);
+    }
+
+    private static void populateDmiCmSubscriptionTuple(final List<String> subscribers,
+                                                       final Map<String, Collection<DmiCmSubscriptionKey>>
+                                                               overlappingSubscriptionsPerDmi,
+                                                       final Map<String, Collection<DmiCmSubscriptionKey>>
+                                                               lastRemainingSubscriptionsPerDmi,
+                                                       final String dmiServiceName,
+                                                       final DmiCmSubscriptionKey dmiCmSubscriptionKey) {
+        final Map<String, Collection<DmiCmSubscriptionKey>> targetMap =
+                subscribers.size() > 1 ? overlappingSubscriptionsPerDmi : lastRemainingSubscriptionsPerDmi;
+        targetMap.computeIfAbsent(dmiServiceName, dmiName -> new HashSet<>()).add(dmiCmSubscriptionKey);
+    }
+
+    private DmiCmSubscriptionKey extractCmSubscriptionKey(final String xpath) {
+        final Matcher matcher = SUBSCRIPTION_KEY_FROM_XPATH_PATTERN.matcher(xpath);
+        if (matcher.find()) {
+            final String datastoreName = matcher.group(1);
+            final String cmHandleId = matcher.group(2);
+            final String filterXpath = matcher.group(3);
+            return new DmiCmSubscriptionKey(datastoreName, cmHandleId, filterXpath);
+        }
+        throw new IllegalArgumentException("DataNode xpath does not represent a subscription key");
+    }
+
 }
\ No newline at end of file
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumer.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumer.java
index 1e1359dd0d..cba64e0e94 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumer.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumer.java
@@ -63,7 +63,7 @@ public class NcmpInEventConsumer {
         if ("subscriptionDeleteRequest".equals(cloudEvent.getType())) {
             log.info("Subscription delete request for source {} with subscription id {} ...",
                     cloudEvent.getSource(), subscriptionId);
-            cmSubscriptionHandler.processSubscriptionDeleteRequest(subscriptionId, predicates);
+            cmSubscriptionHandler.processSubscriptionDeleteRequest(subscriptionId);
         }
     }
 }
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceService.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceService.java
index c24507a1a7..c71109013a 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceService.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceService.java
@@ -159,6 +159,18 @@ public class CmSubscriptionPersistenceService {
         }
     }
 
+    /**
+     * Retrieve all existing dataNodes for given subscription id.
+     *
+     * @param subscriptionId  subscription id
+     * @return collection of DataNodes
+     */
+    public Collection<DataNode> getAllNodesForSubscriptionId(final String subscriptionId) {
+        return cpsQueryService.queryDataNodes(NCMP_DATASPACE_NAME, SUBSCRIPTION_ANCHOR_NAME,
+                CPS_PATH_QUERY_FOR_CM_SUBSCRIPTION_WITH_ID.formatted(subscriptionId),
+                OMIT_DESCENDANTS);
+    }
+
     private void deleteListOfSubscriptionsFor(final DatastoreType datastoreType, final String cmHandleId,
             final String xpath) {
         cpsDataService.deleteDataNode(NCMP_DATASPACE_NAME, SUBSCRIPTION_ANCHOR_NAME,
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandlerSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandlerSpec.groovy
index 2d50e770dd..791a154608 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandlerSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/cache/DmiCacheHandlerSpec.groovy
@@ -65,17 +65,34 @@ class DmiCacheHandlerSpec extends MessagingBaseSpec {
         initialiseMockInventoryPersistenceResponses()
     }
 
-    def 'Load CM subscription event to cache'() {
-        given: 'a valid subscription event with Id'
+    def 'Load CM subscription event to cache with predicates'() {
+        given: 'a subscription event with id'
             def subscriptionId = ncmpInEvent.getData().getSubscriptionId()
         and: 'list of predicates'
             def predicates = ncmpInEvent.getData().getPredicates()
-        when: 'a valid event object loaded in cache'
+        when: 'subscription is loaded to cache with predicates'
             objectUnderTest.add(subscriptionId, predicates)
-        then: 'the cache contains the correct entry with #subscriptionId subscription ID'
+        then: 'the number of entries in cache is correct'
+            assert testCache.size() == 1
+        and: 'the cache contains the correct entries'
             assert testCache.containsKey(subscriptionId)
     }
 
+    def 'Load CM subscription event to cache with dmi subscription details per dmi'() {
+        given: 'a subscription event with id'
+            def subscriptionId = ncmpInEvent.getData().getSubscriptionId()
+        and: 'dmi subscription details per dmi'
+            def dmiSubscriptionsPerDmi = [:]
+        when: 'subscription is loaded to cache with dmi subscription details per dmi'
+            objectUnderTest.add(subscriptionId, dmiSubscriptionsPerDmi)
+        then: 'the number of entries in cache is correct'
+            assert testCache.size() == 1
+        and: 'the cache contains the correct entries'
+            assert testCache.containsKey(subscriptionId)
+        and: 'the entry for the subscription ID matches the provided DMI subscription details'
+            assert testCache.get(subscriptionId) == dmiSubscriptionsPerDmi
+    }
+
     def 'Get cache entry via subscription id'() {
         given: 'the cache contains value for some-id'
             testCache.put('some-id',[:])
@@ -157,7 +174,7 @@ class DmiCacheHandlerSpec extends MessagingBaseSpec {
             def subscriptionId = ncmpInEvent.getData().getSubscriptionId()
             objectUnderTest.add(subscriptionId, predicates)
         when: 'subscription status per dmi is updated in cache'
-            objectUnderTest.updateDmiSubscriptionStatusPerDmi(subscriptionId,'dmi-1', CmSubscriptionStatus.ACCEPTED)
+            objectUnderTest.updateDmiSubscriptionStatus(subscriptionId,'dmi-1', CmSubscriptionStatus.ACCEPTED)
         then: 'verify status has been updated in cache'
             def predicate = testCache.get(subscriptionId)
             assert predicate.get('dmi-1').cmSubscriptionStatus == CmSubscriptionStatus.ACCEPTED
@@ -180,7 +197,7 @@ class DmiCacheHandlerSpec extends MessagingBaseSpec {
             def subscriptionId = ncmpInEvent.getData().getSubscriptionId()
             objectUnderTest.add(subscriptionId, predicates)
         when: 'subscription is persisted in database'
-            objectUnderTest.removeFromDatabasePerDmi(subscriptionId,'dmi-1')
+            objectUnderTest.removeFromDatabase(subscriptionId,'dmi-1')
         then: 'persistence service is called the correct number of times per dmi'
             4 * mockCmSubscriptionPersistenceService.removeCmSubscription(_,_,_,subscriptionId)
     }
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumerSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumerSpec.groovy
index 6e28d14810..bcf8780873 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumerSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/dmi/DmiOutEventConsumerSpec.groovy
@@ -103,7 +103,7 @@ class DmiOutEventConsumerSpec extends MessagingBaseSpec {
         when: 'the event is consumed'
             objectUnderTest.consumeDmiOutEvent(consumerRecord)
         then: 'correct number of calls to cache'
-            expectedCacheCalls * mockDmiCacheHandler.updateDmiSubscriptionStatusPerDmi('sub-1','test-dmi-plugin-name', subscriptionStatus)
+            expectedCacheCalls * mockDmiCacheHandler.updateDmiSubscriptionStatus('sub-1','test-dmi-plugin-name', subscriptionStatus)
         and: 'correct number of calls to persist cache'
             expectedPersistenceCalls * mockDmiCacheHandler.persistIntoDatabasePerDmi('sub-1','test-dmi-plugin-name')
         and: 'correct number of calls to map the ncmp out event'
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImplSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImplSpec.groovy
index 3f6556d47e..f902c60482 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImplSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/CmSubscriptionHandlerImplSpec.groovy
@@ -22,6 +22,7 @@ package org.onap.cps.ncmp.impl.cmnotificationsubscription.ncmp
 
 import com.fasterxml.jackson.databind.ObjectMapper
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.cache.DmiCacheHandler
+import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiCmSubscriptionDetailsPerDmiMapper
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiInEventMapper
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.dmi.DmiInEventProducer
 import org.onap.cps.ncmp.impl.cmnotificationsubscription.models.DmiCmSubscriptionDetails
@@ -30,7 +31,10 @@ import org.onap.cps.ncmp.impl.cmnotificationsubscription.utils.CmSubscriptionPer
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.client_to_ncmp.NcmpInEvent
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.ncmp_to_client.NcmpOutEvent
 import org.onap.cps.ncmp.impl.cmnotificationsubscription_1_0_0.ncmp_to_dmi.DmiInEvent
+import org.onap.cps.ncmp.impl.inventory.InventoryPersistence
+import org.onap.cps.ncmp.impl.inventory.models.YangModelCmHandle
 import org.onap.cps.ncmp.utils.TestUtils
+import org.onap.cps.spi.model.DataNode
 import org.onap.cps.utils.JsonObjectMapper
 import spock.lang.Specification
 
@@ -45,13 +49,15 @@ class CmSubscriptionHandlerImplSpec extends Specification {
     def mockCmSubscriptionComparator = Mock(CmSubscriptionComparator)
     def mockNcmpOutEventMapper = Mock(NcmpOutEventMapper)
     def mockDmiInEventMapper = Mock(DmiInEventMapper)
+    def dmiCmSubscriptionDetailsPerDmiMapper = new DmiCmSubscriptionDetailsPerDmiMapper()
     def mockNcmpOutEventProducer = Mock(NcmpOutEventProducer)
     def mockDmiInEventProducer = Mock(DmiInEventProducer)
     def mockDmiCacheHandler = Mock(DmiCacheHandler)
+    def mockInventoryPersistence = Mock(InventoryPersistence)
 
     def objectUnderTest = new CmSubscriptionHandlerImpl(mockCmSubscriptionPersistenceService,
-        mockCmSubscriptionComparator, mockNcmpOutEventMapper, mockDmiInEventMapper,
-        mockNcmpOutEventProducer, mockDmiInEventProducer, mockDmiCacheHandler)
+        mockCmSubscriptionComparator, mockNcmpOutEventMapper, mockDmiInEventMapper, dmiCmSubscriptionDetailsPerDmiMapper,
+        mockNcmpOutEventProducer, mockDmiInEventProducer, mockDmiCacheHandler, mockInventoryPersistence)
 
     def testDmiSubscriptionsPerDmi = ["dmi-1": new DmiCmSubscriptionDetails([], PENDING)]
 
@@ -97,7 +103,7 @@ class CmSubscriptionHandlerImplSpec extends Specification {
         then: 'the subscription cache handler is called once'
             1 * mockDmiCacheHandler.add('test-id', _)
         and: 'the subscription details are updated in the cache'
-            1 * mockDmiCacheHandler.updateDmiSubscriptionStatusPerDmi('test-id', _, ACCEPTED)
+            1 * mockDmiCacheHandler.updateDmiSubscriptionStatus('test-id', _, ACCEPTED)
         and: 'we schedule to send the response after configured time from the cache'
             1 * mockNcmpOutEventProducer.publishNcmpOutEvent('test-id', 'subscriptionCreateResponse', null, true)
     }
@@ -123,24 +129,44 @@ class CmSubscriptionHandlerImplSpec extends Specification {
     }
 
     def 'Consume valid CmNotificationSubscriptionNcmpInEvent delete message'() {
-        given: 'a cmNotificationSubscriptionNcmp in event for delete'
-            def jsonData = TestUtils.getResourceFileContent('cmSubscription/cmNotificationSubscriptionNcmpInEvent.json')
-            def testEventConsumed = jsonObjectMapper.convertJsonString(jsonData, NcmpInEvent.class)
-        and: 'relevant details is extracted from the event'
-            def subscriptionId = testEventConsumed.getData().getSubscriptionId()
-            def predicates = testEventConsumed.getData().getPredicates()
-        and: 'the cache handler returns for relevant subscription id'
-            1 * mockDmiCacheHandler.get('test-id') >> testDmiSubscriptionsPerDmi
-        when: 'the valid and unique event is consumed'
-            objectUnderTest.processSubscriptionDeleteRequest(subscriptionId, predicates)
-        then: 'the subscription cache handler is called once'
-            1 * mockDmiCacheHandler.add('test-id', predicates)
-        and: 'the mapper handler to get DMI in event is called once'
-            1 * mockDmiInEventMapper.toDmiInEvent(_)
-        and: 'the events handler method to publish DMI event is called correct number of times with the correct parameters'
-            testDmiSubscriptionsPerDmi.size() * mockDmiInEventProducer.publishDmiInEvent(
-                'test-id', 'dmi-1', 'subscriptionDeleteRequest', _)
-        and: 'we schedule to send the response after configured time from the cache'
-            1 * mockNcmpOutEventProducer.publishNcmpOutEvent('test-id', 'subscriptionDeleteResponse', null, true)
+        given: 'a test subscription id'
+            def subscriptionId = 'test-id'
+        and: 'the persistence service returns datanodes'
+            1 * mockCmSubscriptionPersistenceService.getAllNodesForSubscriptionId(subscriptionId) >>
+                [new DataNode(xpath: "/datastores/datastore[@name='ncmp-datastore:passthrough-running']/cm-handles/cm-handle[@id='ch-1']/filters/filter[@xpath='x/y']", leaves: ['xpath': 'x/y', 'subscriptionIds': ['test-id']]),
+                new DataNode(xpath: "/datastores/datastore[@name='ncmp-datastore:passthrough-running']/cm-handles/cm-handle[@id='ch-2']/filters/filter[@xpath='y/z']", leaves: ['xpath': 'y/z', 'subscriptionIds': ['test-id']])]
+        and: 'the inventory persistence returns yang model cm handles'
+            1 * mockInventoryPersistence.getYangModelCmHandle('ch-1') >> new YangModelCmHandle(dmiServiceName: 'dmi-1')
+            1 * mockInventoryPersistence.getYangModelCmHandle('ch-2') >> new YangModelCmHandle(dmiServiceName: 'dmi-2')
+        when: 'the subscription delete request is processed'
+            objectUnderTest.processSubscriptionDeleteRequest(subscriptionId)
+        then: 'the method to publish a dmi event is called with correct parameters'
+            1 * mockDmiInEventProducer.publishDmiInEvent(subscriptionId,'dmi-1','subscriptionDeleteRequest',_)
+            1 * mockDmiInEventProducer.publishDmiInEvent(subscriptionId,'dmi-2','subscriptionDeleteRequest',_)
+        and: 'the method to publish nmcp out event is called with correct parameters'
+            1 * mockNcmpOutEventProducer.publishNcmpOutEvent(subscriptionId, 'subscriptionDeleteResponse', null, true)
+    }
+
+    def 'Delete a subscriber for fully overlapping subscriptions'() {
+        given: 'a test subscription id'
+            def subscriptionId = 'test-id'
+        and: 'the persistence service returns datanodes with multiple subscribers'
+            1 * mockCmSubscriptionPersistenceService.getAllNodesForSubscriptionId(subscriptionId) >>
+                [new DataNode(xpath: "/datastores/datastore[@name='ncmp-datastore:passthrough-running']/cm-handles/cm-handle[@id='ch-1']/filters/filter[@xpath='x/y']", leaves: ['xpath': 'x/y', 'subscriptionIds': ['test-id','other-id']]),
+                 new DataNode(xpath: "/datastores/datastore[@name='ncmp-datastore:passthrough-running']/cm-handles/cm-handle[@id='ch-2']/filters/filter[@xpath='y/z']", leaves: ['xpath': 'y/z', 'subscriptionIds': ['test-id','other-id']])]
+        and: 'the inventory persistence returns yang model cm handles'
+            1 * mockInventoryPersistence.getYangModelCmHandle('ch-1') >> new YangModelCmHandle(dmiServiceName: 'dmi-1')
+            1 * mockInventoryPersistence.getYangModelCmHandle('ch-2') >> new YangModelCmHandle(dmiServiceName: 'dmi-2')
+        and: 'the cache handler returns the relevant maps whenever called'
+            2 * mockDmiCacheHandler.get(subscriptionId) >> ['dmi-1':[:],'dmi-2':[:]]
+        when: 'the subscription delete request is processed'
+            objectUnderTest.processSubscriptionDeleteRequest(subscriptionId)
+        then: 'the method to publish a dmi event is never called'
+            0 * mockDmiInEventProducer.publishDmiInEvent(_,_,_,_)
+        and: 'the cache handler is called to remove subscriber from database per dmi'
+            1 * mockDmiCacheHandler.removeFromDatabase('test-id', 'dmi-1')
+            1 * mockDmiCacheHandler.removeFromDatabase('test-id', 'dmi-2')
+        and: 'the method to publish nmcp out event is called with correct parameters'
+            1 * mockNcmpOutEventProducer.publishNcmpOutEvent(subscriptionId, 'subscriptionDeleteResponse', null, false)
     }
 }
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumerSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumerSpec.groovy
index 2881737e82..9c24e2b005 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumerSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/ncmp/NcmpInEventConsumerSpec.groovy
@@ -100,7 +100,7 @@ class NcmpInEventConsumerSpec extends MessagingBaseSpec {
         and: 'the log indicates the task completed successfully'
             assert loggingEvent.formattedMessage == 'Subscription delete request for source some-resource with subscription id test-id ...'
         and: 'the subscription handler service is called once'
-            1 * mockCmSubscriptionHandler.processSubscriptionDeleteRequest('test-id',_)
+            1 * mockCmSubscriptionHandler.processSubscriptionDeleteRequest('test-id')
     }
 
 
diff --git a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceServiceSpec.groovy b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceServiceSpec.groovy
index d32d143ade..354e2af937 100644
--- a/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceServiceSpec.groovy
+++ b/cps-ncmp-service/src/test/groovy/org/onap/cps/ncmp/impl/cmnotificationsubscription/utils/CmSubscriptionPersistenceServiceSpec.groovy
@@ -188,4 +188,17 @@ class CmSubscriptionPersistenceServiceSpec extends Specification {
             'cm handle in same datastore is NOT used for other subscriptions' | []               || 1
     }
 
+    def 'Get all nodes for subscription id'() {
+        given: 'the query service returns nodes for subscription id'
+            def expectedDataNode = new DataNode(xpath: '/some/xpath')
+            def queryServiceResponse = [expectedDataNode].asCollection()
+            1 * mockCpsQueryService.queryDataNodes('NCMP-Admin', 'cm-data-subscriptions', '//filter/subscriptionIds[text()=\'some-id\']', OMIT_DESCENDANTS) >> queryServiceResponse
+        when: 'retrieving all nodes for subscription id'
+            def result = objectUnderTest.getAllNodesForSubscriptionId('some-id')
+        then: 'the result returns correct number of datanodes'
+            assert result.size() == 1
+        and: 'the attribute of the datanode is as expected'
+            assert result.iterator().next().xpath == expectedDataNode.xpath
+    }
+
 }