| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| package org.apache.apex.malhar.sql.planner; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.apex.malhar.sql.operators.OperatorUtils; |
| import org.apache.apex.malhar.sql.schema.TupleSchemaRegistry; |
| |
| import org.apache.calcite.adapter.java.JavaTypeFactory; |
| import org.apache.calcite.rel.RelNode; |
| |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| import com.datatorrent.api.Context; |
| import com.datatorrent.api.DAG; |
| import com.datatorrent.api.Operator; |
| |
| /** |
| * This class is the main class that converts relational algebra to a sub-DAG. |
| * |
| * @since 3.6.0 |
| */ |
| @InterfaceStability.Evolving |
| public class RelNodeVisitor |
| { |
| private final DAG dag; |
| private final TupleSchemaRegistry tupleSchemaRegistry; |
| private final JavaTypeFactory typeFactory; |
| |
| public RelNodeVisitor(DAG dag, JavaTypeFactory typeFactory) |
| { |
| this.dag = dag; |
| this.typeFactory = typeFactory; |
| this.tupleSchemaRegistry = new TupleSchemaRegistry(); |
| } |
| |
| /** |
| * This is the main method in this relational node visitor which traverses the relational algebra in reverse direction |
| * and populate the given underlying DAG object. |
| * |
| * @param relNode RelNode which needs to be traversed. |
| * |
| * @return RelInfo representing information of current stage |
| * @throws Exception |
| */ |
| public final RelInfo traverse(RelNode relNode) throws Exception |
| { |
| List<RelInfo> inputStreams = new ArrayList<>(); |
| for (RelNode input : relNode.getInputs()) { |
| inputStreams.add(traverse(input)); |
| } |
| |
| ApexRelNode.RelContext relContext = new ApexRelNode.RelContext(dag, typeFactory, tupleSchemaRegistry); |
| |
| RelInfo currentNodeRelInfo; |
| ApexRelNode apexRelNode = ApexRelNode.relNodeMapping.get(relNode.getClass()); |
| if (apexRelNode == null) { |
| throw new UnsupportedOperationException("RelNode " + relNode.getRelTypeName() + " is not supported."); |
| } |
| currentNodeRelInfo = apexRelNode.visit(relContext, relNode, inputStreams); |
| |
| if (currentNodeRelInfo != null && inputStreams.size() != 0) { |
| for (int i = 0; i < inputStreams.size(); i++) { |
| RelInfo inputStream = inputStreams.get(i); |
| Operator.OutputPort outputPort = inputStream.getOutPort(); |
| Operator.InputPort inputPort = currentNodeRelInfo.getInputPorts().get(i); |
| |
| String streamName = OperatorUtils.getUniqueStreamName(inputStream.getRelName(), |
| currentNodeRelInfo.getRelName()); |
| Class schema; |
| if (inputStream.getOutRelDataType() != null) { |
| schema = TupleSchemaRegistry.getSchemaForRelDataType(tupleSchemaRegistry, streamName, |
| inputStream.getOutRelDataType()); |
| } else if (inputStream.getClazz() != null) { |
| schema = inputStream.getClazz(); |
| } else { |
| throw new RuntimeException("Unexpected condition reached."); |
| } |
| dag.setOutputPortAttribute(outputPort, Context.PortContext.TUPLE_CLASS, schema); |
| dag.setInputPortAttribute(inputPort, Context.PortContext.TUPLE_CLASS, schema); |
| dag.addStream(streamName, outputPort, inputPort); |
| } |
| } |
| |
| if (currentNodeRelInfo.getOutPort() == null) { |
| // End of the pipeline. |
| String schemaJar = tupleSchemaRegistry.generateCommonJar(); |
| |
| String jars = dag.getAttributes().get(Context.DAGContext.LIBRARY_JARS); |
| dag.setAttribute(Context.DAGContext.LIBRARY_JARS, |
| ((jars != null) && (jars.length() != 0)) ? jars + "," + schemaJar : schemaJar); |
| } |
| |
| return currentNodeRelInfo; |
| } |
| } |