CPS-1401 Implement V2 of GET Data Node API

- Modified the GET Data Node API so it returns all the data nodes when
  xpath set to root "/"
- Fragment Repository now returns a collection of Fragment Entities
- Instead of returning only the first Fragment Entity now all fragment
  entities are returned when xpath is set to root
- The Fragemnt Entities are further processed to a Collection of Data
  Nodes. As opposed to singular Data Node in current implementation.
- Finally the DataRestController also returns a Collection of Data
  Nodes when xpath is set to root and valid data is present
- Response body changed from JSON object to JSON Array.
- Exception handling for invalid xpath and non-existing xpath is now
  done separately at persistence layer.
- Refactored code against CPS-1422
- Deprecated getDataNode method from Service and Persistence layer
- Modified V1 of Get Data Node API to use the getDataNodes method and
  get the first data node from the collection returned.
- Modified NCMP to use getDataNodes method
- NCMP still does not support multiple data nodes. It retrieves the
  first data node from the collection returned by getDataNodes

Signed-off-by: arpitsingh <as00745003@techmahindra.com>
Change-Id: I494a5740a53f65376d135fcb9f1e2e8900a2803e

6 files changed, 31 insertions, 22 deletions

diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyCmHandlerQueryServiceImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyCmHandlerQueryServiceImpl.java
index b67ae0c19e..a98c6008cf 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyCmHandlerQueryServiceImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyCmHandlerQueryServiceImpl.java
@@ -1,6 +1,7 @@
 /*
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2022 Nordix Foundation
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -217,8 +218,8 @@ public class NetworkCmProxyCmHandlerQueryServiceImpl implements NetworkCmProxyCm
         final Map<String, NcmpServiceCmHandle> queryResult = new HashMap<>(cmHandleIdsByModuleName.size());
         if (previousQueryResult == NO_QUERY_TO_EXECUTE) {
             cmHandleIdsByModuleName.forEach(cmHandleId ->
-                    queryResult.put(cmHandleId, createNcmpServiceCmHandle(
-                            inventoryPersistence.getDataNode("/dmi-registry/cm-handles[@id='" + cmHandleId + "']")))
+                    queryResult.put(cmHandleId, createNcmpServiceCmHandle(inventoryPersistence
+                            .getDataNode("/dmi-registry/cm-handles[@id='" + cmHandleId + "']").iterator().next()))
             );
             return queryResult;
         }
@@ -298,13 +299,14 @@ public class NetworkCmProxyCmHandlerQueryServiceImpl implements NetworkCmProxyCm
     }
 
     private Set<NcmpServiceCmHandle> getAllCmHandles() {
-        return inventoryPersistence.getDataNode("/dmi-registry")
-                .getChildDataNodes().stream().map(this::createNcmpServiceCmHandle).collect(Collectors.toSet());
+        final DataNode dataNode = inventoryPersistence.getDataNode("/dmi-registry").iterator().next();
+        return dataNode.getChildDataNodes().stream().map(this::createNcmpServiceCmHandle).collect(Collectors.toSet());
     }
 
     private Set<String> getAllCmHandleIds() {
-        return inventoryPersistence.getDataNode("/dmi-registry", FETCH_DIRECT_CHILDREN_ONLY)
-                .getChildDataNodes().stream().map(dataNode -> dataNode.getLeaves().get("id").toString())
+        final DataNode dataNodes = inventoryPersistence.getDataNode("/dmi-registry", FETCH_DIRECT_CHILDREN_ONLY)
+                .iterator().next();
+        return dataNodes.getChildDataNodes().stream().map(dataNode -> dataNode.getLeaves().get("id").toString())
                 .collect(Collectors.toSet());
     }
 
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServiceImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServiceImpl.java
index e71b72ab86..d5500b8d7a 100755
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServiceImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServiceImpl.java
@@ -4,6 +4,7 @@
  *  Modifications Copyright (C) 2021-2023 Nordix Foundation
  *  Modifications Copyright (C) 2021 Pantheon.tech
  *  Modifications Copyright (C) 2021-2022 Bell Canada
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -131,8 +132,8 @@ public class NetworkCmProxyDataServiceImpl implements NetworkCmProxyDataService
     public Object getResourceDataOperational(final String cmHandleId,
                                              final String resourceIdentifier,
                                              final FetchDescendantsOption fetchDescendantsOption) {
-        return cpsDataService.getDataNode(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId, resourceIdentifier,
-                fetchDescendantsOption);
+        return cpsDataService.getDataNodes(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId, resourceIdentifier,
+                fetchDescendantsOption).iterator().next();
     }
 
     @Override
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServicePropertyHandler.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServicePropertyHandler.java
index f39c2f9b60..bbb2c0f56f 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServicePropertyHandler.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/impl/NetworkCmProxyDataServicePropertyHandler.java
@@ -2,6 +2,7 @@
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2022 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -66,7 +67,8 @@ public class NetworkCmProxyDataServicePropertyHandler {
         for (final NcmpServiceCmHandle ncmpServiceCmHandle : ncmpServiceCmHandles) {
             final String cmHandleId = ncmpServiceCmHandle.getCmHandleId();
             try {
-                final DataNode existingCmHandleDataNode = inventoryPersistence.getCmHandleDataNode(cmHandleId);
+                final DataNode existingCmHandleDataNode = inventoryPersistence.getCmHandleDataNode(cmHandleId)
+                        .iterator().next();
                 processUpdates(existingCmHandleDataNode, ncmpServiceCmHandle);
                 cmHandleRegistrationResponses.add(CmHandleRegistrationResponse.createSuccessResponse(cmHandleId));
             } catch (final DataNodeNotFoundException e) {
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/CmHandleQueriesImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/CmHandleQueriesImpl.java
index bda0a728b4..0f86cb7be6 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/CmHandleQueriesImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/CmHandleQueriesImpl.java
@@ -1,6 +1,7 @@
 /*
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2022 Nordix Foundation
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -174,8 +175,8 @@ public class CmHandleQueriesImpl implements CmHandleQueries {
 
     private DataNode getCmHandleState(final String cmHandleId) {
         final String xpath = "/dmi-registry/cm-handles[@id='" + cmHandleId + "']/state";
-        return cpsDataPersistenceService.getDataNode(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
-                xpath, OMIT_DESCENDANTS);
+        return cpsDataPersistenceService.getDataNodes(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
+                xpath, OMIT_DESCENDANTS).iterator().next();
     }
 }
 
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistence.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistence.java
index 10227cf26f..d22cf0e16a 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistence.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistence.java
@@ -1,6 +1,7 @@
 /*
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2022-2023 Nordix Foundation
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -119,7 +120,7 @@ public interface InventoryPersistence {
      * @param xpath xpath
      * @return data node
      */
-    DataNode getDataNode(String xpath);
+    Collection<DataNode> getDataNode(String xpath);
 
     /**
      * Get data node via xpath.
@@ -128,7 +129,7 @@ public interface InventoryPersistence {
      * @param fetchDescendantsOption fetch descendants option
      * @return data node
      */
-    DataNode getDataNode(String xpath, FetchDescendantsOption fetchDescendantsOption);
+    Collection<DataNode> getDataNode(String xpath, FetchDescendantsOption fetchDescendantsOption);
 
     /**
      * Get collection of data nodes via xpaths.
@@ -153,7 +154,7 @@ public interface InventoryPersistence {
      * @param cmHandleId cmHandle ID
      * @return data node
      */
-    DataNode getCmHandleDataNode(String cmHandleId);
+    Collection<DataNode> getCmHandleDataNode(String cmHandleId);
 
     /**
      * Get collection of data nodes of given cm handles.
diff --git a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistenceImpl.java b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistenceImpl.java
index 4d1202b065..1c799c6b26 100644
--- a/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistenceImpl.java
+++ b/cps-ncmp-service/src/main/java/org/onap/cps/ncmp/api/inventory/InventoryPersistenceImpl.java
@@ -2,6 +2,7 @@
  *  ============LICENSE_START=======================================================
  *  Copyright (C) 2022-2023 Nordix Foundation
  *  Modifications Copyright (C) 2022 Bell Canada
+ *  Modifications Copyright (C) 2023 TechMahindra Ltd.
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -73,9 +74,9 @@ public class InventoryPersistenceImpl implements InventoryPersistence {
 
     @Override
     public CompositeState getCmHandleState(final String cmHandleId) {
-        final DataNode stateAsDataNode = cpsDataService.getDataNode(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
+        final DataNode stateAsDataNode = cpsDataService.getDataNodes(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
                 createCmHandleXPath(cmHandleId) + "/state",
-                FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS);
+                FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS).iterator().next();
         cpsValidator.validateNameCharacters(cmHandleId);
         return new CompositeStateBuilder().fromDataNode(stateAsDataNode).build();
     }
@@ -101,7 +102,8 @@ public class InventoryPersistenceImpl implements InventoryPersistence {
     @Override
     public YangModelCmHandle getYangModelCmHandle(final String cmHandleId) {
         cpsValidator.validateNameCharacters(cmHandleId);
-        return YangDataConverter.convertCmHandleToYangModel(getCmHandleDataNode(cmHandleId), cmHandleId);
+        final DataNode dataNode = getCmHandleDataNode(cmHandleId).iterator().next();
+        return YangDataConverter.convertCmHandleToYangModel(dataNode, cmHandleId);
     }
 
     @Override
@@ -169,15 +171,15 @@ public class InventoryPersistenceImpl implements InventoryPersistence {
     @Override
     @Timed(value = "cps.ncmp.inventory.persistence.datanode.get",
             description = "Time taken to get a data node (from ncmp dmi registry)")
-    public DataNode getDataNode(final String xpath) {
+    public Collection<DataNode> getDataNode(final String xpath) {
         return getDataNode(xpath, INCLUDE_ALL_DESCENDANTS);
     }
 
     @Override
     @Timed(value = "cps.ncmp.inventory.persistence.datanode.get",
             description = "Time taken to get a data node (from ncmp dmi registry)")
-    public DataNode getDataNode(final String xpath, final FetchDescendantsOption fetchDescendantsOption) {
-        return cpsDataService.getDataNode(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
+    public Collection<DataNode> getDataNode(final String xpath, final FetchDescendantsOption fetchDescendantsOption) {
+        return cpsDataService.getDataNodes(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
                 xpath, fetchDescendantsOption);
     }
 
@@ -189,12 +191,12 @@ public class InventoryPersistenceImpl implements InventoryPersistence {
     @Override
     public Collection<DataNode> getDataNodes(final Collection<String> xpaths,
                                              final FetchDescendantsOption fetchDescendantsOption) {
-        return cpsDataService.getDataNodes(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
+        return cpsDataService.getDataNodesForMultipleXpaths(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR,
                 xpaths, fetchDescendantsOption);
     }
 
     @Override
-    public DataNode getCmHandleDataNode(final String cmHandleId) {
+    public Collection<DataNode> getCmHandleDataNode(final String cmHandleId) {
         return this.getDataNode(createCmHandleXPath(cmHandleId));
     }