1 files changed, 198 insertions, 0 deletions
diff --git a/aai-core/src/main/java/org/onap/aai/serialization/engines/query/GraphTraversalQueryEngine.java b/aai-core/src/main/java/org/onap/aai/serialization/engines/query/GraphTraversalQueryEngine.java
new file mode 100644
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--- /dev/null
+++ b/aai-core/src/main/java/org/onap/aai/serialization/engines/query/GraphTraversalQueryEngine.java
@@ -0,0 +1,198 @@
+/**
+ * ============LICENSE_START=======================================================
+ * org.onap.aai
+ * ================================================================================
+ * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ *
+ * ECOMP is a trademark and service mark of AT&T Intellectual Property.
+ */
+package org.onap.aai.serialization.engines.query;
+
+
+import static org.onap.aai.serialization.db.AAIDirection.IN;
+import static org.onap.aai.serialization.db.AAIDirection.NONE;
+import static org.onap.aai.serialization.db.AAIDirection.OUT;
+import static org.onap.aai.serialization.db.EdgeProperty.CONTAINS;
+import static org.onap.aai.serialization.db.EdgeProperty.DELETE_OTHER_V;
+
+import java.util.List;
+import java.util.Set;
+
+import org.apache.tinkerpop.gremlin.process.traversal.P;
+import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal;
+import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
+import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.__;
+import org.apache.tinkerpop.gremlin.process.traversal.step.util.Tree;
+import org.apache.tinkerpop.gremlin.structure.Direction;
+import org.apache.tinkerpop.gremlin.structure.Edge;
+import org.apache.tinkerpop.gremlin.structure.Element;
+import org.apache.tinkerpop.gremlin.structure.Vertex;
+import org.onap.aai.db.props.AAIProperties;
+import org.onap.aai.introspection.Loader;
+
+/*
+ * This class needs some big explanation despite its compact size.
+ * This controls all the queries performed by the CRUD API in A&AI. 
+ * findParents, findChildren, and findDeletable require special attention
+ *   These methods use 'repeat'. You cannot use 'emit' with repeat currently
+ *   as it is extremely buggy as of tinkerpop-3.0.1-incubating. The way around
+ *   it (for now) is to sideEffect all the vertices we traverse into an ArrayList.
+ * 
+ */
+public class GraphTraversalQueryEngine extends QueryEngine {
+
+	/**
+	 * Instantiates a new graph traversal query engine.
+	 *
+	 * @param graphEngine the graph engine
+	 */
+	public GraphTraversalQueryEngine(GraphTraversalSource g) {
+		super(g);
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public List<Vertex> findParents(Vertex start) {
+		
+		final GraphTraversal<Vertex, Vertex> pipe = this.g.V(start).emit(v -> true).repeat(__.union(__.inE().has(CONTAINS.toString(), OUT.toString()).outV(), __.outE().has(CONTAINS.toString(), IN.toString()).inV()));
+		return pipe.toList();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public List<Vertex> findAllChildren(Vertex start) {
+		
+		GraphTraversal<Vertex, Vertex> pipe =  this.g
+				.V(start).emit(v -> true).repeat(__.union(__.outE().has(CONTAINS.toString(), OUT.toString()).inV(), __.inE().has(CONTAINS.toString(), IN.toString()).outV()));
+		
+
+		return pipe.toList();
+		
+	}
+
+	public List<Vertex> findChildrenOfType(Vertex start, String type) {
+		GraphTraversal<Vertex, Vertex> pipe =  this.g.V(start).union(
+					__.outE().has(CONTAINS.toString(), OUT.toString()).inV(),
+					__.inE().has(CONTAINS.toString(), IN.toString()).outV()
+				).has(AAIProperties.NODE_TYPE, type).dedup();
+ 
+		return pipe.toList();
+	}
+	
+	public List<Vertex> findChildren(Vertex start) {
+		GraphTraversal<Vertex, Vertex> pipe =  this.g.V(start).union(
+					__.outE().has(CONTAINS.toString(), OUT.toString()),
+					__.inE().has(CONTAINS.toString(), IN.toString())
+				).otherV().dedup();
+ 
+		return pipe.toList();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public List<Vertex> findDeletable(Vertex start) {
+		GraphTraversal<Vertex, Vertex> pipe = this.g
+				.V(start).emit(v -> true).repeat(
+					__.union(
+						__.outE().or(
+							__.has(CONTAINS.toString(), OUT.toString()),
+							__.has(DELETE_OTHER_V.toString(), OUT.toString())
+						).inV(),
+						__.inE().or(
+								__.has(CONTAINS.toString(), IN.toString()),
+								__.has(DELETE_OTHER_V.toString(), IN.toString())
+						).outV()
+					)
+				);
+		
+		return pipe.toList();
+	}
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public List<Vertex> findRelatedVertices(Vertex start, Direction direction, String label, String nodeType) {
+		GraphTraversal<Vertex, Vertex> pipe = this.g.V(start);
+		switch (direction) {
+			case OUT:
+				pipe.out(label);
+				break;
+			case IN:
+				pipe.in(label);
+				break;
+			case BOTH:
+				pipe.both(label);
+				break;
+			 default:
+				break;
+		}
+		
+		pipe.has(AAIProperties.NODE_TYPE, nodeType).dedup();
+		return pipe.toList();
+	}
+	
+	@Override
+	public Tree<Element> findSubGraph(Vertex start, int iterations, boolean nodeOnly) {
+		final GraphTraversal<Vertex, ?> t = this.g.V(start).emit(v -> true).times(iterations).repeat(
+				__.union(
+					__.outE().has(CONTAINS.toString(), OUT.toString()).inV(),
+					__.inE().has(CONTAINS.toString(), IN.toString()).outV())
+				);
+			
+		if (!nodeOnly) {
+			t.union(
+					__.identity(),
+					__.bothE().has(CONTAINS.toString(), NONE.toString()).dedup().otherV()
+			);
+		}
+		t.tree();
+		if (t.hasNext()) {
+			return (Tree)t.next();
+		} else {
+			return new Tree();
+		}
+	}
+
+	@Override
+	public List<Edge> findEdgesForVersion(Vertex start, Loader loader) {
+		final Set<String> objects = loader.getAllObjects().keySet();
+		GraphTraversal<Vertex, Edge> pipeline = this.g.V(start).union(
+				__.inE().has(CONTAINS.toString(), NONE.toString()).where(__.outV().has(AAIProperties.NODE_TYPE, P.within(objects))),
+				__.outE().has(CONTAINS.toString(), NONE.toString()).where(__.inV().has(AAIProperties.NODE_TYPE, P.within(objects)))
+			).dedup();
+		
+		return pipeline.toList();
+	}
+
+
+	@Override
+	public List<Vertex> findCousinVertices(Vertex start) {
+		GraphTraversal<Vertex, Vertex> pipeline = this.g.V(start).union(
+				__.inE().has(CONTAINS.toString(), NONE.toString()),
+				__.outE().has(CONTAINS.toString(), NONE.toString())).otherV().dedup();
+				
+		return pipeline.toList();
+	}
+	
+}
+