Add bulk API to gizmo
[aai/gizmo.git] / src / main / java / org / openecomp / crud / dao / champ / ChampDao.java
index 31bc9ab..ed01038 100644 (file)
  */
 package org.openecomp.crud.dao.champ;
 
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
 import org.openecomp.aai.champcore.ChampGraph;
+import org.openecomp.aai.champcore.ChampTransaction;
 import org.openecomp.aai.champcore.exceptions.ChampMarshallingException;
 import org.openecomp.aai.champcore.exceptions.ChampObjectNotExistsException;
 import org.openecomp.aai.champcore.exceptions.ChampRelationshipNotExistsException;
@@ -41,628 +50,770 @@ import org.openecomp.crud.entity.Vertex;
 import org.openecomp.crud.exception.CrudException;
 import org.openecomp.crud.logging.CrudServiceMsgs;
 
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
-
-
 /**
- * This is the integration layer between the CRUD API service and the low level Champ library
- * for graph database interaction.
+ * This is the integration layer between the CRUD API service and the low level Champ library for graph database
+ * interaction.
  */
 public class ChampDao implements GraphDao {
 
-  public static final String CONFIG_STORAGE_BACKEND = "storage.backend";
-  public static final String CONFIG_STORAGE_BACKEND_DB = "storage.backend.db";
-  public static final String STORAGE_HBASE_DB = "hbase";
-  public static final String STORAGE_CASSANDRA_DB = "cassandra";
-  public static final String CONFIG_STORAGE_HOSTNAMES = "storage.hostnames";
-  public static final String CONFIG_STORAGE_PORT = "storage.port";
-  public static final String CONFIG_HBASE_ZNODE_PARENT = "storage.hbase.ext.zookeeper.znode.parent";
-  public static final String CONFIG_GRAPH_NAME = "graph.name";
-  public static final String GRAPH_UNQ_INSTANCE_ID_SUFFIX = "graph.unique-instance-id-suffix";
-
-  public static final String CONFIG_EVENT_STREAM_PUBLISHER = "event.stream.publisher";
-  public static final String CONFIG_EVENT_STREAM_NUM_PUBLISHERS = "event.stream.num-publishers";
-
-
-  public static final String DEFAULT_GRAPH_NAME = "default_graph";
-
-  private enum GraphType {
-    IN_MEMORY,
-    TITAN,
-    DSE
-  }
-  
-  /**
-   * Instance of the API used for interacting with the Champ library.
-   */
-  private ChampGraph champApi = null;
-
-  private Logger logger = LoggerFactory.getInstance().getLogger(ChampDao.class.getName());
-
-
-  /**
-   * Creates a new instance of the ChampDao.
-   *
-   * @param champGraph - Concrete implementation of the graph dao layer
-   */
-  public ChampDao(ChampGraph champGraph) {
-       this.champApi = champGraph;
-  }
-
-  @Override
-  public Vertex getVertex(String id) throws CrudException {
-    
-    try {
-      
-      if (logger.isDebugEnabled()) {
-        logger.debug("getVertex with id: " + id);
-      }
-      
-      long idAsLong = Long.parseLong(id);
-      
-      Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
-      
-      String nodeType = org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName();
-      if(retrievedVertex.isPresent() && 
-         retrievedVertex.get().getProperties().get(nodeType)!=null) {
-        return vertexFromChampObject(retrievedVertex.get(), 
-                                     retrievedVertex.get().getProperties().get(nodeType).toString());
-      } else {
-
-        // We didn't find a vertex with the supplied id, so just throw an
-        // exception.
-        throw new CrudException("No vertex with id " + id + " found in graph",
-                                javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-      
-    } catch (ChampUnmarshallingException | ChampTransactionException e) {
-
-      // Something went wrong - throw an exception.
-      throw new CrudException(e.getMessage(),
-                              javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-  
-  @Override
-  public Vertex getVertex(String id, String type) throws CrudException {
-
-    try {
-
-      if (logger.isDebugEnabled()) {
-        logger.debug("getVertex with id: " + id);
-      }
-
-      long idAsLong = Long.parseLong(id);
-
-      // Request the vertex from the graph db.
-      Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
-
-      // Did we find it?
-      if (retrievedVertex.isPresent() && retrievedVertex.get().getProperties()
-          .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName())!=null && retrievedVertex.get().getProperties()
-          .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()
-          .equalsIgnoreCase(type)) {  
-        
-        // Yup, convert it to a Vector object and return it.
-        return vertexFromChampObject(retrievedVertex.get(),type);
-
-      } else {
-
-        // We didn't find a vertex with the supplied id, so just throw an
-        // exception.
-        throw new CrudException("No vertex with id " + id + " found in graph",
-            javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-
-    } catch (ChampUnmarshallingException | ChampTransactionException e) {
-
-      // Something went wrong - throw an exception.
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-
-
-  @Override
-  public List<Edge> getVertexEdges(String id) throws CrudException {
-
-    if (logger.isDebugEnabled()) {
-      logger.debug("get Edges incident to vertex with id: " + id + " from graph");
-    }
-
-    try {
-      long idAsLong = Long.parseLong(id); // GDF - what to do about id???
-
-      // Request the vertex from the graph db.
-      Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
-
-      // Did we find it?
-      if (retrievedVertex.isPresent()) {
-
-        // Query the Champ library for the edges which are incident to the specified
-        // vertex.
-        Stream<ChampRelationship> relationships =
-            champApi.retrieveRelationships(retrievedVertex.get());
-
-        // Build an edge list from the result stream.
-        List<Edge> edges = new ArrayList<Edge>();
-        relationships.forEach(r -> edges.add(edgeFromChampRelationship(r)));
-
-        return edges;
-
-      } else {
-
-        // We couldn't find the specified vertex, so throw an exception.
-        throw new CrudException("No vertex with id " + id + " found in graph",
-            javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-
-    } catch (ChampUnmarshallingException e) {
-
-      // Something went wrong, so throw an exception.
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+       public static final String CONFIG_STORAGE_BACKEND = "storage.backend";
+       public static final String CONFIG_STORAGE_BACKEND_DB = "storage.backend.db";
+       public static final String STORAGE_HBASE_DB = "hbase";
+       public static final String STORAGE_CASSANDRA_DB = "cassandra";
+       public static final String CONFIG_STORAGE_HOSTNAMES = "storage.hostnames";
+       public static final String CONFIG_STORAGE_PORT = "storage.port";
+       public static final String CONFIG_HBASE_ZNODE_PARENT = "storage.hbase.ext.zookeeper.znode.parent";
+       public static final String CONFIG_GRAPH_NAME = "graph.name";
+       public static final String GRAPH_UNQ_INSTANCE_ID_SUFFIX = "graph.unique-instance-id-suffix";
+
+       public static final String CONFIG_EVENT_STREAM_PUBLISHER = "event.stream.publisher";
+       public static final String CONFIG_EVENT_STREAM_NUM_PUBLISHERS = "event.stream.num-publishers";
+
+       private static Map<String, ChampTransaction> transactions = new ConcurrentHashMap<String, ChampTransaction>();
+       public static final String DEFAULT_GRAPH_NAME = "default_graph";
+
+       private enum GraphType {
+               IN_MEMORY, TITAN, DSE
+       }
+
+       /**
+        * Instance of the API used for interacting with the Champ library.
+        */
+       private ChampGraph champApi = null;
+
+       private Logger logger = LoggerFactory.getInstance().getLogger(ChampDao.class.getName());
+
+       /**
+        * Creates a new instance of the ChampDao.
+        *
+        * @param champGraph
+        *            - Concrete implementation of the graph dao layer
+        */
+       public ChampDao(ChampGraph champGraph) {
+               this.champApi = champGraph;
+       }
+
+       @Override
+       public Vertex getVertex(String id) throws CrudException {
+
+               try {
+
+                       if (logger.isDebugEnabled()) {
+                               logger.debug("getVertex with id: " + id);
+                       }
+
+                       long idAsLong = Long.parseLong(id);
+
+                       Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
+
+                       String nodeType = org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName();
+                       if (retrievedVertex.isPresent() && retrievedVertex.get().getProperties().get(nodeType) != null) {
+                               return vertexFromChampObject(retrievedVertex.get(), retrievedVertex.get().getProperties().get(nodeType).toString());
+                       } else {
+
+                               // We didn't find a vertex with the supplied id, so just throw an
+                               // exception.
+                               throw new CrudException("No vertex with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+               } catch (ChampUnmarshallingException | ChampTransactionException e) {
+
+                       // Something went wrong - throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public Vertex getVertex(String id, String type) throws CrudException {
+
+               try {
+
+                       if (logger.isDebugEnabled()) {
+                               logger.debug("getVertex with id: " + id);
+                       }
+
+                       long idAsLong = Long.parseLong(id);
+
+                       // Request the vertex from the graph db.
+                       Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
+
+                       // Did we find it?
+                       if (retrievedVertex.isPresent()
+                                       && retrievedVertex.get().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()) != null
+                                       && retrievedVertex.get().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()
+                                                       .equalsIgnoreCase(type)) {
+
+                               // Yup, convert it to a Vector object and return it.
+                               return vertexFromChampObject(retrievedVertex.get(), type);
+
+                       } else {
+
+                               // We didn't find a vertex with the supplied id, so just throw an
+                               // exception.
+                               throw new CrudException("No vertex with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+               } catch (ChampUnmarshallingException | ChampTransactionException e) {
+
+                       // Something went wrong - throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public List<Edge> getVertexEdges(String id) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("get Edges incident to vertex with id: " + id + " from graph");
+               }
+
+               try {
+                       long idAsLong = Long.parseLong(id); // GDF - what to do about id???
+
+                       // Request the vertex from the graph db.
+                       Optional<ChampObject> retrievedVertex = champApi.retrieveObject(idAsLong);
+
+                       // Did we find it?
+                       if (retrievedVertex.isPresent()) {
+
+                               // Query the Champ library for the edges which are incident to the specified
+                               // vertex.
+                               Stream<ChampRelationship> relationships = champApi.retrieveRelationships(retrievedVertex.get());
+
+                               // Build an edge list from the result stream.
+                               List<Edge> edges = new ArrayList<Edge>();
+                               relationships.forEach(r -> edges.add(edgeFromChampRelationship(r)));
+
+                               return edges;
+
+                       } else {
+
+                               // We couldn't find the specified vertex, so throw an exception.
+                               throw new CrudException("No vertex with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+               } catch (ChampUnmarshallingException e) {
+
+                       // Something went wrong, so throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+
+               } catch (ChampObjectNotExistsException e) {
+
+                       // We couldn't find the specified vertex, so throw an exception.
+                       throw new CrudException("No vertex with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Transaction error occured", javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public Vertex addVertex(String type, Map<String, Object> properties) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Add/update vertex: {label: " + type + " properties:" + propertiesMapToString(properties));
+               }
+
+               // Add the aai_node_type so that AAI can read the data created by gizmo
+               properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+
+               // Create an object to represent our vertex in the format expected by the Champ library.
+               ChampObject objectToCreate = buildChampObject(type, properties);
+
+               try {
+
+                       // Ask the Champ library to store our vertex, placing the returned object into a
+                       // list so that we can easily put that into our result object.
+                       return vertexFromChampObject(champApi.storeObject(objectToCreate), type);
+
+               } catch (ChampMarshallingException | ChampSchemaViolationException | ChampObjectNotExistsException | ChampTransactionException e) {
+
+                       // Something went wrong - throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public Vertex updateVertex(String id, String type, Map<String, Object> properties) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Update vertex with id: " + id + " with properties: " + propertiesMapToString(properties));
+               }
+               // Add the aai_node_type so that AAI can read the data created by gizmo
+               properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+
+               try {
+                       // Now, build the updated version of the Champ Object...
+                       ChampObject updateObject = buildChampObject(id, type, properties);
+                       // ...and send it to the Champ library.
+                       return vertexFromChampObject(champApi.replaceObject(updateObject), type);
+
+               } catch (ChampObjectNotExistsException e) {
+                       throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
+               } catch (NumberFormatException | ChampMarshallingException | ChampSchemaViolationException e) {
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Transaction error occured", javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+
+       }
+
+       @Override
+       public List<Vertex> getVertices(String type, Map<String, Object> filter) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Retrieve vertices with type label: " + type + " which map query parameters: " + propertiesMapToString(filter));
+               }
+
+               filter.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+
+               Stream<ChampObject> retrievedVertices;
+               try {
+                       retrievedVertices = champApi.queryObjects(filter);
+
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Transaction error occured", javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+
+               List<Vertex> vertices = retrievedVertices.map(v -> vertexFromChampObject(v, type)).collect(Collectors.toList());
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Resulting vertex list: " + retrievedVertices);
+               }
+
+               // ...and return it to the caller.
+               return vertices;
+       }
+
+       private Object getRelKey(String id) {
+               Object key = id;
+               // convert into Long if applicable . TODO : revisit in story NUC-304
+               try {
+                       key = Long.parseLong(id);
+               } catch (NumberFormatException e) {
+                       // The id isn't a Long, leave it as a string
+               }
+
+               return key;
+       }
+
+       @Override
+       public Edge getEdge(String id, String type) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Get edge with id: " + id);
+               }
+
+               try {
+
+                       // Request the edge from the graph db.
+                       Optional<ChampRelationship> relationship = champApi.retrieveRelationship(getRelKey(id));
+
+                       // Did we find it?
+                       if (relationship.isPresent() && relationship.get().getType().equals(type)) {
+
+                               // Yup - return the result.
+                               return edgeFromChampRelationship(relationship.get());
+
+                       } else {
+
+                               // We didn't find an edge with the supplied id, so throw an exception.
+                               throw new CrudException("No edge with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+               } catch (ChampUnmarshallingException | ChampTransactionException e) {
+
+                       // Something went wrong, so throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public Edge addEdge(String type, Vertex source, Vertex target, Map<String, Object> properties) throws CrudException {
+
+               // For now, assume source and target are straight ids...
+               try {
+
+                       Optional<ChampObject> sourceObject = champApi.retrieveObject(Long.parseLong(source.getId().get()));
+                       if (!sourceObject.isPresent() || !sourceObject.get().getType().equals(source.getType())) {
+                               throw new CrudException("Error creating edge - source vertex with id " + source + " does not exist in graph data base",
+                                               javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       Optional<ChampObject> targetObject = champApi.retrieveObject(Long.parseLong(target.getId().get()));
+                       if (!targetObject.isPresent() || !targetObject.get().getType().equals(target.getType())) {
+                               throw new CrudException("Error creating edge - target vertex with id " + target + " does not exist in graph data base",
+                                               javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       // Now, create the ChampRelationship object for our edge and store it in
+                       // the graph database.
+                       return edgeFromChampRelationship(
+                                       champApi.storeRelationship(new ChampRelationship.Builder(sourceObject.get(), targetObject.get(), type).properties(properties).build()));
+
+               } catch (ChampMarshallingException | ChampObjectNotExistsException | ChampSchemaViolationException | ChampRelationshipNotExistsException
+                               | ChampUnmarshallingException | NumberFormatException | ChampTransactionException e) {
+
+                       throw new CrudException("Error creating edge: " + e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public List<Edge> getEdges(String type, Map<String, Object> filter) throws CrudException {
+
+               filter.put(ChampRelationship.ReservedPropertyKeys.CHAMP_RELATIONSHIP_TYPE.toString(), type);
+
+               Stream<ChampRelationship> retrievedRelationships;
+               try {
+                       retrievedRelationships = champApi.queryRelationships(filter);
+
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Transaction error occured", javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+
+               // Process the result stream from the Champ library into an Edge list, keeping only
+               // edges of the specified type.
+               List<Edge> edges = retrievedRelationships.map(r -> edgeFromChampRelationship(r)).collect(Collectors.toList());
+
+               return edges;
+       }
+
+       @Override
+       public Edge updateEdge(Edge edge) throws CrudException {
+
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Update edge with id: " + edge.getId() + " with properties: " + propertiesMapToString(edge.getProperties()));
+               }
+
+               try {
+                       // Now, build the updated version of the Champ Relationship...
+                       ChampRelationship updateRelationship = new ChampRelationship.Builder(
+                                       buildChampObject(edge.getSource().getId().get(), edge.getSource().getType(), edge.getSource().getProperties()),
+                                       buildChampObject(edge.getTarget().getId().get(), edge.getTarget().getType(), edge.getTarget().getProperties()), edge.getType())
+                                                       .key(getRelKey(edge.getId().get())).properties(edge.getProperties()).build();
+                       // ...and send it to the Champ library.
+                       return edgeFromChampRelationship(champApi.replaceRelationship(updateRelationship));
+
+               } catch (ChampRelationshipNotExistsException ex) {
+                       throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
+               } catch (NumberFormatException | ChampUnmarshallingException | ChampMarshallingException | ChampSchemaViolationException
+                               | ChampTransactionException ex) {
+
+                       throw new CrudException(ex.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public void deleteVertex(String id, String type) throws CrudException {
+
+               try {
+
+                       // First, retrieve the vertex that we intend to delete.
+                       Optional<ChampObject> retrievedVertex = champApi.retrieveObject(Long.parseLong(id));
+
+                       // Did we find it?
+                       if (!retrievedVertex.isPresent() || !retrievedVertex.get().getType().equals(type)) {
+                               throw new CrudException("Failed to delete vertex with id: " + id + " - vertex does not exist.", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+                       // Now, verify that there are no edges incident to the vertex (they must be deleted
+                       // first if so).
+                       Stream<ChampRelationship> relationships = champApi.retrieveRelationships(retrievedVertex.get());
+
+                       if (relationships.count() > 0) {
+                               throw new CrudException("Attempt to delete vertex with id " + id + " which has incident edges.", javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       // Finally, we can attempt to delete our vertex.
+                       champApi.deleteObject(Long.parseLong(id));
+
+               } catch (NumberFormatException | ChampUnmarshallingException | ChampObjectNotExistsException | ChampTransactionException e) {
+
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public void deleteEdge(String id, String type) throws CrudException {
+
+               try {
+
+                       // First, retrieve the edge that we want to delete.
+                       Optional<ChampRelationship> relationshipToDelete = champApi.retrieveRelationship(getRelKey(id));
+
+                       // Did we find it?
+                       if (!relationshipToDelete.isPresent() || !relationshipToDelete.get().getType().equals(type)) {
+                               throw new CrudException("Failed to delete edge with id: " + id + " - edge does not exist", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+                       // Now we can delete the edge.
+                       champApi.deleteRelationship(relationshipToDelete.get());
+
+               } catch (ChampRelationshipNotExistsException | NumberFormatException | ChampUnmarshallingException | ChampTransactionException e) {
+
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       /**
+        * This helper method generates a string representation of a properties map for logging purposes.
+        *
+        * @param properties
+        *            - The properties map to be converted.
+        * @return - The log statement friendly conversion of the properties map.
+        */
+       private String propertiesMapToString(Map<String, Object> properties) {
+
+               StringBuilder sb = new StringBuilder();
+               sb.append("{");
+
+               for (String key : properties.keySet()) {
+                       sb.append("(").append(key).append(" -> ").append(properties.get(key)).append(") ");
+               }
+
+               sb.append("}");
+
+               return sb.toString();
+       }
+
+       /**
+        * This helper method constructs a {@link ChampObject} suitable for passing to the Champ library.
+        *
+        * @param type
+        *            - The type to assign to our ChampObject
+        * @param properties
+        *            - The set of properties to assign to our ChampObject
+        * @return - A populated ChampObject
+        */
+       private ChampObject buildChampObject(String type, Map<String, Object> properties) {
+
+               ObjectBuildOrPropertiesStep objectInProgress = ChampObject.create().ofType(type).withoutKey();
+
+               for (String key : properties.keySet()) {
+                       objectInProgress.withProperty(key, properties.get(key));
+               }
+               return objectInProgress.build();
+       }
+
+       /**
+        * This helper method constructs a {@link ChampObject} suitable for passing to the Champ library.
+        *
+        * @param id
+        *            - Unique identifier for this object.
+        * @param type
+        *            - The type to assign to our ChampObject
+        * @param properties
+        *            - The set of properties to assign to our ChampObject
+        * @return - A populated ChampObject
+        */
+       private ChampObject buildChampObject(String id, String type, Map<String, Object> properties) {
+
+               ObjectBuildOrPropertiesStep objectInProgress = ChampObject.create().ofType(type).withKey(Long.parseLong(id));
+
+               for (String key : properties.keySet()) {
+                       objectInProgress.withProperty(key, properties.get(key));
+               }
+               return objectInProgress.build();
+       }
+
+       private Vertex vertexFromChampObject(ChampObject champObject, String type) {
+
+               // Get the identifier for this vertex from the Champ object.
+               Object id = champObject.getKey().orElse("");
+
+               // Start building our {@link Vertex} object.
+               Vertex.Builder vertexBuilder = new Vertex.Builder(type);
+               vertexBuilder.id(id.toString());
+
+               // Convert the properties associated with the Champ object into the form expected for
+               // a Vertex object.
+               for (String key : champObject.getProperties().keySet()) {
+                       vertexBuilder.property(key, champObject.getProperties().get(key));
+               }
+
+               // ...and return it.
+               return vertexBuilder.build();
+       }
+
+       /**
+        * This helper method converts a {@link ChampRelationship} from the Champ library into an equivalent {@link Edge}
+        * object that is understood by the CRUD Service.
+        *
+        * @param relationship
+        *            - The ChampRelationship object to be converted.
+        * @return - An Edge object corresponding to the supplied ChampRelationship
+        */
+       private Edge edgeFromChampRelationship(ChampRelationship relationship) {
+
+               // Populate the edge's id, if available.
+               Object relationshipId = relationship.getKey().orElse("");
+
+               Edge.Builder edgeBuilder = new Edge.Builder(relationship.getType()).id(relationshipId.toString());
+               edgeBuilder.source(vertexFromChampObject(relationship.getSource(),
+                               relationship.getSource().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()) == null
+                                               ? relationship.getSource().getType()
+                                               : relationship.getSource().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()));
+               edgeBuilder.target(vertexFromChampObject(relationship.getTarget(),
+                               relationship.getTarget().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()) == null
+                                               ? relationship.getTarget().getType()
+                                               : relationship.getTarget().getProperties().get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()));
+
+               for (String key : relationship.getProperties().keySet()) {
+                       edgeBuilder.property(key, relationship.getProperties().get(key).toString());
+               }
+
+               return edgeBuilder.build();
+       }
+
+       /**
+        * Performs any necessary shut down operations when the DAO is no longer needed.
+        */
+       public void close() {
+
+               if (champApi != null) {
+
+                       logger.info(CrudServiceMsgs.STOPPING_CHAMP_DAO);
+
+                       champApi.shutdown();
+               }
+       }
+
+       @Override
+       public String openTransaction() {
+
+               ChampTransaction transaction = champApi.openTransaction();
+
+               transactions.put(transaction.id(), transaction);
+               logger.info(CrudServiceMsgs.TRANSACTION, "Stored transaction " + transaction.id() + " in hashmap");
+               logger.info(CrudServiceMsgs.TRANSACTION, "Hash map contents:");
+               for (String key : transactions.keySet()) {
+                       logger.info(CrudServiceMsgs.TRANSACTION, key);
+               }
+               return transaction.id();
+       }
+
+       @Override
+       public void commitTransaction(String id) throws CrudException {
+
+               try {
+                       champApi.commitTransaction(getTransaction(id));
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Error while commiting transaction " + id, javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+               transactions.remove(id);
+       }
+
+       @Override
+       public void rollbackTransaction(String id) throws CrudException {
+
+               try {
+                       champApi.rollbackTransaction(getTransaction(id));
+               } catch (ChampTransactionException e) {
+                       throw new CrudException("Error while transaction rollback " + id, javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+               transactions.remove(id);
+       }
+
+       private ChampTransaction getTransaction(String id) throws CrudException {
+
+               logger.info(CrudServiceMsgs.TRANSACTION, "Looking up transaction " + id);
+               if (transactions.containsKey(id)) {
+                       logger.info(CrudServiceMsgs.TRANSACTION, "Found it!");
+                       return (transactions.get(id));
+               } else {
+                       logger.info(CrudServiceMsgs.TRANSACTION, "Didn't find transaction id " + id + ".  Hash map contains: ");
+                       for (String key : transactions.keySet()) {
+                               logger.info(CrudServiceMsgs.TRANSACTION, key);
+                       }
+                       throw new CrudException("No open transaction with id: " + id, javax.ws.rs.core.Response.Status.NOT_FOUND);
+               }
+       }
+
+       @Override
+       public Vertex addVertex(String type, Map<String, Object> properties, String txId) throws CrudException {
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Add/update vertex: {label: " + type + " properties:" + propertiesMapToString(properties));
+               }
+
+               // Add the aai_node_type so that AAI can read the data created by gizmo
+               properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+
+               // Create an object to represent our vertex in the format expected by the Champ library.
+               ChampObject objectToCreate = buildChampObject(type, properties);
+
+               try {
+
+                       // Ask the Champ library to store our vertex, placing the returned object into a
+                       // list so that we can easily put that into our result object.
+                       return vertexFromChampObject(champApi.storeObject(objectToCreate, Optional.of(getTransaction(txId))), type);
+
+               } catch (ChampMarshallingException | ChampSchemaViolationException | ChampObjectNotExistsException | ChampTransactionException e) {
+
+                       // Something went wrong - throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public Edge addEdge(String type, Vertex source, Vertex target, Map<String, Object> properties, String txId) throws CrudException {
+               // For now, assume source and target are straight ids...
+               try {
+
+                       Optional<ChampObject> sourceObject = champApi.retrieveObject(Long.parseLong(source.getId().get()), Optional.of(getTransaction(txId)));
+                       if (!sourceObject.isPresent() || !sourceObject.get().getType().equals(source.getType())) {
+                               throw new CrudException("Error creating edge - source vertex with id " + source + " does not exist in graph data base",
+                                               javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       Optional<ChampObject> targetObject = champApi.retrieveObject(Long.parseLong(target.getId().get()), Optional.of(getTransaction(txId)));
+                       if (!targetObject.isPresent() || !targetObject.get().getType().equals(target.getType())) {
+                               throw new CrudException("Error creating edge - target vertex with id " + target + " does not exist in graph data base",
+                                               javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       // Now, create the ChampRelationship object for our edge and store it in
+                       // the graph database.
+                       return edgeFromChampRelationship(
+                                       champApi.storeRelationship(new ChampRelationship.Builder(sourceObject.get(), targetObject.get(), type).properties(properties).build(),
+                                                       Optional.of(getTransaction(txId))));
+
+               } catch (ChampMarshallingException | ChampObjectNotExistsException | ChampSchemaViolationException | ChampTransactionException
+                               | ChampRelationshipNotExistsException | ChampUnmarshallingException e) {
+
+                       throw new CrudException("Error creating edge: " + e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+
+       }
+
+       @Override
+       public Vertex updateVertex(String id, String type, Map<String, Object> properties, String txId) throws CrudException {
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Update vertex with id: " + id + " with properties: " + propertiesMapToString(properties));
+               }
+               // Add the aai_node_type so that AAI can read the data created by gizmo
+               properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+
+               try {
+                       // Now, build the updated version of the Champ Object...
+                       ChampObject updateObject = buildChampObject(id, type, properties);
+                       // ...and send it to the Champ library.
+                       return vertexFromChampObject(champApi.replaceObject(updateObject, Optional.of(getTransaction(txId))), type);
+
+               } catch (ChampObjectNotExistsException e) {
+                       throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
+               } catch (NumberFormatException | ChampMarshallingException | ChampTransactionException | ChampSchemaViolationException e) {
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
+
+       @Override
+       public boolean transactionExists(String id) throws CrudException {
+               return transactions.containsKey(id);
+       }
+
+       @Override
+       public void deleteVertex(String id, String type, String txId) throws CrudException {
+               try {
+
+                       // First, retrieve the vertex that we intend to delete.
+                       Optional<ChampObject> retrievedVertex = champApi.retrieveObject(Long.parseLong(id), Optional.of(getTransaction(txId)));
+
+                       // Did we find it?
+                       if (!retrievedVertex.isPresent() || !retrievedVertex.get().getType().equals(type)) {
+                               throw new CrudException("Failed to delete vertex with id: " + id + " - vertex does not exist.", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
+
+                       // Now, verify that there are no edges incident to the vertex (they must be deleted
+                       // first if so).
+                       Stream<ChampRelationship> relationships = champApi.retrieveRelationships(retrievedVertex.get(), Optional.of(getTransaction(txId)));
+
+                       if (relationships.count() > 0) {
+                               throw new CrudException("Attempt to delete vertex with id " + id + " which has incident edges.", javax.ws.rs.core.Response.Status.BAD_REQUEST);
+                       }
+
+                       // Finally, we can attempt to delete our vertex.
+                       champApi.deleteObject(Long.parseLong(id), Optional.of(getTransaction(txId)));
 
-    } catch (ChampObjectNotExistsException e) {
+               } catch (NumberFormatException | ChampUnmarshallingException | ChampObjectNotExistsException | ChampTransactionException e) {
 
-      // We couldn't find the specified vertex, so throw an exception.
-      throw new CrudException("No vertex with id " + id + " found in graph",
-          javax.ws.rs.core.Response.Status.NOT_FOUND);
-    } catch (ChampTransactionException e) {
-      throw new CrudException("Transaction error occured",
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
 
+       }
 
-  @Override
-  public Vertex addVertex(String type, Map<String, Object> properties) throws CrudException {
+       @Override
+       public Edge updateEdge(Edge edge, String txId) throws CrudException {
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Update edge with id: " + edge.getId() + " with properties: " + propertiesMapToString(edge.getProperties()));
+               }
 
-    if (logger.isDebugEnabled()) {
-      logger.debug("Add/update vertex: {label: " + type
-          + " properties:" + propertiesMapToString(properties));
-    }
+               try {
+                       // Now, build the updated version of the Champ Relationship...
+                       ChampRelationship updateRelationship = new ChampRelationship.Builder(
+                                       buildChampObject(edge.getSource().getId().get(), edge.getSource().getType(), edge.getSource().getProperties()),
+                                       buildChampObject(edge.getTarget().getId().get(), edge.getTarget().getType(), edge.getTarget().getProperties()), edge.getType())
+                                                       .key(getRelKey(edge.getId().get())).properties(edge.getProperties()).build();
+                       // ...and send it to the Champ library.
+                       return edgeFromChampRelationship(champApi.replaceRelationship(updateRelationship, Optional.of(getTransaction(txId))));
 
-    //Add the aai_node_type so that AAI can read the data created by gizmo
-    properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+               } catch (ChampRelationshipNotExistsException ex) {
+                       throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
+               } catch (NumberFormatException | ChampUnmarshallingException | ChampMarshallingException | ChampSchemaViolationException
+                               | ChampTransactionException ex) {
 
-    // Create an object to represent our vertex in the format expected by the Champ library.
-    ChampObject objectToCreate = buildChampObject(type, properties);
+                       throw new CrudException(ex.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
 
-    try {
+       @Override
+       public void deleteEdge(String id, String type, String txId) throws CrudException {
+               try {
 
-      // Ask the Champ library to store our vertex, placing the returned object into a
-      // list so that we can easily put that into our result object.
-      return vertexFromChampObject(champApi.storeObject(objectToCreate),type);
+                       // First, retrieve the edge that we want to delete.
+                       Optional<ChampRelationship> relationshipToDelete = champApi.retrieveRelationship(getRelKey(id), Optional.of(getTransaction(txId)));
 
-    } catch (ChampMarshallingException
-        | ChampSchemaViolationException
-        | ChampObjectNotExistsException 
-        | ChampTransactionException e) {
+                       // Did we find it?
+                       if (!relationshipToDelete.isPresent() || !relationshipToDelete.get().getType().equals(type)) {
+                               throw new CrudException("Failed to delete edge with id: " + id + " - edge does not exist", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
 
-      // Something went wrong - throw an exception.
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
+                       // Now we can delete the edge.
+                       champApi.deleteRelationship(relationshipToDelete.get(), Optional.of(getTransaction(txId)));
 
+               } catch (ChampRelationshipNotExistsException | NumberFormatException | ChampUnmarshallingException | ChampTransactionException e) {
 
-  @Override
-  public Vertex updateVertex(String id, String type, Map<String, Object> properties)
-      throws CrudException {
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
 
-    if (logger.isDebugEnabled()) {
-      logger.debug("Update vertex with id: " + id + " with properties: "
-          + propertiesMapToString(properties));
-    }
-    //Add the aai_node_type so that AAI can read the data created by gizmo
-    properties.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+       }
 
-    try {
-      // Now, build the updated version of the Champ Object...
-      ChampObject updateObject = buildChampObject(id, type, properties);
-      // ...and send it to the Champ library.
-      return vertexFromChampObject(champApi.replaceObject(updateObject),type);
+       @Override
+       public Edge getEdge(String id, String type, String txId) throws CrudException {
+               if (logger.isDebugEnabled()) {
+                       logger.debug("Get edge with id: " + id);
+               }
 
-    } catch (ChampObjectNotExistsException e) {
-      throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
-    } catch (NumberFormatException | ChampMarshallingException | ChampSchemaViolationException e) {
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    } catch (ChampTransactionException e) {
-      throw new CrudException("Transaction error occured",
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
+               try {
 
-  }
+                       // Request the edge from the graph db.
+                       Optional<ChampRelationship> relationship = champApi.retrieveRelationship(getRelKey(id), Optional.of(getTransaction(txId)));
 
+                       // Did we find it?
+                       if (relationship.isPresent() && relationship.get().getType().equals(type)) {
 
-  @Override
-  public List<Vertex> getVertices(String type, Map<String, Object> filter) throws CrudException {
+                               // Yup - return the result.
+                               return edgeFromChampRelationship(relationship.get());
 
-    if (logger.isDebugEnabled()) {
-      logger.debug("Retrieve vertices with type label: " + type + " which map query parameters: "
-          + propertiesMapToString(filter));
-    }
+                       } else {
 
+                               // We didn't find an edge with the supplied id, so throw an exception.
+                               throw new CrudException("No edge with id " + id + " found in graph", javax.ws.rs.core.Response.Status.NOT_FOUND);
+                       }
 
-    filter.put(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName(), type);
+               } catch (ChampUnmarshallingException | ChampTransactionException e) {
 
+                       // Something went wrong, so throw an exception.
+                       throw new CrudException(e.getMessage(), javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
+               }
+       }
 
-    Stream<ChampObject> retrievedVertices;
-    try {
-      retrievedVertices = champApi.queryObjects(filter);
-      
-    } catch (ChampTransactionException e) {
-      throw new CrudException("Transaction error occured",
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-
-    List<Vertex> vertices = retrievedVertices
-        .map(v -> vertexFromChampObject(v,type))
-        .collect(Collectors.toList());
-
-
-    if (logger.isDebugEnabled()) {
-      logger.debug("Resulting vertex list: " + retrievedVertices);
-    }
-
-    // ...and return it to the caller.
-    return vertices;
-  }
-
-  private Object getRelKey(String id) {
-    Object key = id;
-    // convert into Long if applicable . TODO : revisit in story NUC-304
-    try {
-      key = Long.parseLong(id);
-    } catch (NumberFormatException e) {
-      // The id isn't a Long, leave it as a string
-    }
-
-    return key;
-  }
-
-  @Override
-  public Edge getEdge(String id, String type) throws CrudException {
-
-    if (logger.isDebugEnabled()) {
-      logger.debug("Get edge with id: " + id);
-    }
-
-    try {
-
-      // Request the edge from the graph db.
-      Optional<ChampRelationship> relationship = champApi.retrieveRelationship(getRelKey(id));
-
-      // Did we find it?
-      if (relationship.isPresent() && relationship.get().getType().equals(type)) {
-
-        // Yup - return the result.
-        return edgeFromChampRelationship(relationship.get());
-
-      } else {
-
-        // We didn't find an edge with the supplied id, so throw an exception.
-        throw new CrudException("No edge with id " + id + " found in graph",
-            javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-
-    } catch (ChampUnmarshallingException | ChampTransactionException e) {
-
-      // Something went wrong, so throw an exception.
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-
-  @Override
-  public Edge addEdge(String type,
-                      Vertex source,
-                      Vertex target,
-                      Map<String, Object> properties) throws CrudException {
-
-    // For now, assume source and target are straight ids...
-    try {
-
-      Optional<ChampObject> sourceObject
-          = champApi.retrieveObject(Long.parseLong(source.getId().get()));
-      if (!sourceObject.isPresent() || !sourceObject.get().getType().equals(source.getType())) {
-        throw new CrudException("Error creating edge - source vertex with id " + source
-            + " does not exist in graph data base",
-            javax.ws.rs.core.Response.Status.BAD_REQUEST);
-      }
-
-      Optional<ChampObject> targetObject
-          = champApi.retrieveObject(Long.parseLong(target.getId().get()));
-      if (!targetObject.isPresent() || !targetObject.get().getType().equals(target.getType())) {
-        throw new CrudException("Error creating edge - target vertex with id " + target
-            + " does not exist in graph data base",
-            javax.ws.rs.core.Response.Status.BAD_REQUEST);
-      }
-
-      // Now, create the ChampRelationship object for our edge and store it in
-      // the graph database.
-      return edgeFromChampRelationship(
-          champApi.storeRelationship(
-              new ChampRelationship.Builder(sourceObject.get(), targetObject.get(), type)
-                  .properties(properties)
-                  .build()));
-
-    } catch (ChampMarshallingException
-        | ChampObjectNotExistsException
-        | ChampSchemaViolationException
-        | ChampRelationshipNotExistsException
-        | ChampUnmarshallingException | NumberFormatException | ChampTransactionException e) {
-
-      throw new CrudException("Error creating edge: " + e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-
-
-  @Override
-  public List<Edge> getEdges(String type, Map<String, Object> filter) throws CrudException {
-
-    filter.put(ChampRelationship.ReservedPropertyKeys.CHAMP_RELATIONSHIP_TYPE.toString(), type);
-
-    Stream<ChampRelationship> retrievedRelationships;
-    try {
-      retrievedRelationships = champApi.queryRelationships(filter);
-      
-    } catch (ChampTransactionException e) {
-      throw new CrudException("Transaction error occured",
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-    
-    // Process the result stream from the Champ library into an Edge list, keeping only
-    // edges of the specified type.
-    List<Edge> edges = retrievedRelationships
-        .map(r -> edgeFromChampRelationship(r))
-        .collect(Collectors.toList());
-
-    return edges;
-  }
-
-  @Override
-  public Edge updateEdge(Edge edge) throws CrudException {
-
-    if (logger.isDebugEnabled()) {
-      logger.debug("Update edge with id: " + edge.getId() + " with properties: "
-          + propertiesMapToString(edge.getProperties()));
-    }
-
-    try {
-      // Now, build the updated version of the Champ Relationship...
-      ChampRelationship updateRelationship = new ChampRelationship.Builder(
-          buildChampObject(edge.getSource().getId().get(), edge.getSource().getType(),
-              edge.getSource().getProperties()),
-          buildChampObject(edge.getTarget().getId().get(), edge.getTarget().getType(),
-              edge.getTarget().getProperties()),
-          edge.getType()).key(getRelKey(edge.getId().get()))
-          .properties(edge.getProperties()).build();
-      // ...and send it to the Champ library.
-      return edgeFromChampRelationship(champApi.replaceRelationship(updateRelationship));
-
-
-    } catch (ChampRelationshipNotExistsException ex) {
-      throw new CrudException("Not Found", javax.ws.rs.core.Response.Status.NOT_FOUND);
-    } catch (NumberFormatException | 
-             ChampUnmarshallingException | 
-             ChampMarshallingException | 
-             ChampSchemaViolationException |
-             ChampTransactionException ex) {
-
-      throw new CrudException(ex.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    } 
-  }
-
-  @Override
-  public void deleteVertex(String id, String type) throws CrudException {
-
-    try {
-
-      // First, retrieve the vertex that we intend to delete.
-      Optional<ChampObject> retrievedVertex = champApi.retrieveObject(Long.parseLong(id));
-
-      // Did we find it?
-      if (!retrievedVertex.isPresent() || !retrievedVertex.get().getType().equals(type)) {
-        throw new CrudException("Failed to delete vertex with id: "
-            + id + " - vertex does not exist.",
-            javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-
-      // Now, verify that there are no edges incident to the vertex (they must be deleted
-      // first if so).
-      Stream<ChampRelationship> relationships =
-          champApi.retrieveRelationships(retrievedVertex.get());
-
-      if (relationships.count() > 0) {
-        throw new CrudException("Attempt to delete vertex with id "
-            + id + " which has incident edges.",
-            javax.ws.rs.core.Response.Status.BAD_REQUEST);
-      }
-
-      // Finally, we can attempt to delete our vertex.
-      champApi.deleteObject(Long.parseLong(id));
-
-
-    } catch (NumberFormatException
-           | ChampUnmarshallingException
-           | ChampObjectNotExistsException 
-           | ChampTransactionException e) {
-
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-
-  @Override
-  public void deleteEdge(String id, String type) throws CrudException {
-
-    try {
-
-      // First, retrieve the edge that we want to delete.
-      Optional<ChampRelationship> relationshipToDelete
-          = champApi.retrieveRelationship(getRelKey(id));
-
-
-      // Did we find it?
-      if (!relationshipToDelete.isPresent() || !relationshipToDelete.get().getType().equals(type)) {
-        throw new CrudException("Failed to delete edge with id: " + id + " - edge does not exist",
-            javax.ws.rs.core.Response.Status.NOT_FOUND);
-      }
-
-      // Now we can delete the edge.
-      champApi.deleteRelationship(relationshipToDelete.get());
-
-    } catch (ChampRelationshipNotExistsException
-        | NumberFormatException
-        | ChampUnmarshallingException 
-        | ChampTransactionException e) {
-
-      throw new CrudException(e.getMessage(),
-          javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR);
-    }
-  }
-
-
-  /**
-   * This helper method generates a string representation of a properties map for
-   * logging purposes.
-   *
-   * @param properties - The properties map to be converted.
-   * @return - The log statement friendly conversion of the properties map.
-   */
-  private String propertiesMapToString(Map<String, Object> properties) {
-
-    StringBuilder sb = new StringBuilder();
-    sb.append("{");
-
-    for (String key : properties.keySet()) {
-      sb.append("(").append(key).append(" -> ").append(properties.get(key)).append(") ");
-    }
-
-    sb.append("}");
-
-    return sb.toString();
-  }
-
-
-  /**
-   * This helper method constructs a {@link ChampObject} suitable for passing to the Champ library.
-   *
-   * @param type       - The type to assign to our ChampObject
-   * @param properties - The set of properties to assign to our ChampObject
-   * @return - A populated ChampObject
-   */
-  private ChampObject buildChampObject(String type, Map<String, Object> properties) {
-
-    ObjectBuildOrPropertiesStep objectInProgress = ChampObject.create()
-        .ofType(type)
-        .withoutKey();
-
-    for (String key : properties.keySet()) {
-      objectInProgress.withProperty(key, properties.get(key));
-    }
-    return objectInProgress.build();
-  }
-
-
-  /**
-   * This helper method constructs a {@link ChampObject} suitable for passing to the Champ library.
-   *
-   * @param id         - Unique identifier for this object.
-   * @param type       - The type to assign to our ChampObject
-   * @param properties - The set of properties to assign to our ChampObject
-   * @return - A populated ChampObject
-   */
-  private ChampObject buildChampObject(String id, String type, Map<String, Object> properties) {
-
-    ObjectBuildOrPropertiesStep objectInProgress = ChampObject.create()
-        .ofType(type)
-        .withKey(Long.parseLong(id));
-
-    for (String key : properties.keySet()) {
-      objectInProgress.withProperty(key, properties.get(key));
-    }
-    return objectInProgress.build();
-  }
-
-
-  
-  
-  private Vertex vertexFromChampObject(ChampObject champObject, String type) {
-
-    // Get the identifier for this vertex from the Champ object.
-    Object id = champObject.getKey().orElse("");
-
-    // Start building our {@link Vertex} object.
-    Vertex.Builder vertexBuilder = new Vertex.Builder(type);
-    vertexBuilder.id(id.toString());
-
-    // Convert the properties associated with the Champ object into the form expected for
-    // a Vertex object.
-    for (String key : champObject.getProperties().keySet()) {
-      vertexBuilder.property(key, champObject.getProperties().get(key));
-    }
-
-    // ...and return it.
-    return vertexBuilder.build();
-  }
-
-
-  /**
-   * This helper method converts a {@link ChampRelationship} from the Champ library into an
-   * equivalent {@link Edge} object that is understood by the CRUD Service.
-   *
-   * @param relationship - The ChampRelationship object to be converted.
-   * @return - An Edge object corresponding to the supplied ChampRelationship
-   */
-  private Edge edgeFromChampRelationship(ChampRelationship relationship) {
-
-    // Populate the edge's id, if available.
-    Object relationshipId = relationship.getKey().orElse("");
-
-    Edge.Builder edgeBuilder = new Edge.Builder(relationship.getType())
-        .id(relationshipId.toString());
-    edgeBuilder.source(vertexFromChampObject(relationship.getSource(),
-        relationship.getSource().getProperties()
-            .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()) == null
-                ? relationship.getSource().getType()
-                : relationship.getSource().getProperties()
-                    .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()));
-    edgeBuilder.target(vertexFromChampObject(relationship.getTarget(),
-        relationship.getTarget().getProperties()
-            .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()) == null
-                ? relationship.getTarget().getType()
-                : relationship.getTarget().getProperties()
-                    .get(org.openecomp.schema.OxmModelValidator.Metadata.NODE_TYPE.propertyName()).toString()));
-
-    for (String key : relationship.getProperties().keySet()) {
-      edgeBuilder.property(key, relationship.getProperties().get(key).toString());
-    }
-
-    return edgeBuilder.build();
-  }
-
-  /**
-   * Performs any necessary shut down operations when the DAO is no longer needed.
-   */
-  public void close() {
-
-    if (champApi != null) {
-
-      logger.info(CrudServiceMsgs.STOPPING_CHAMP_DAO);
-
-      champApi.shutdown();
-    }
-  }
 }