HuangXingBo commented on a change in pull request #14473: URL: https://github.com/apache/flink/pull/14473#discussion_r547951233
########## File path: flink-table/flink-table-planner-blink/src/main/java/org/apache/flink/table/planner/plan/rules/logical/PythonCalcMergeRule.java ########## @@ -0,0 +1,167 @@ +/* + * 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.flink.table.planner.plan.rules.logical; + +import org.apache.flink.table.planner.plan.nodes.logical.FlinkLogicalCalc; +import org.apache.flink.table.planner.plan.utils.PythonUtil; + +import org.apache.calcite.plan.RelOptRule; +import org.apache.calcite.plan.RelOptRuleCall; +import org.apache.calcite.rel.core.Calc; +import org.apache.calcite.rex.RexBuilder; +import org.apache.calcite.rex.RexCall; +import org.apache.calcite.rex.RexFieldAccess; +import org.apache.calcite.rex.RexInputRef; +import org.apache.calcite.rex.RexNode; +import org.apache.calcite.rex.RexProgram; +import org.apache.calcite.rex.RexProgramBuilder; + +import java.util.Collections; +import java.util.List; +import java.util.stream.Collectors; + +/** + * Rule will merge Python {@link FlinkLogicalCalc} used in Map operation, Flatten {@link FlinkLogicalCalc} + * and Python {@link FlinkLogicalCalc} used in Map operation together. + */ +public class PythonCalcMergeRule extends RelOptRule { + + public static final PythonCalcMergeRule INSTANCE = new PythonCalcMergeRule(); + + private PythonCalcMergeRule() { + super(operand(FlinkLogicalCalc.class, + operand(FlinkLogicalCalc.class, + operand(FlinkLogicalCalc.class, none()))), + "PythonCalcMergeRule"); + } + + @Override + public boolean matches(RelOptRuleCall call) { + FlinkLogicalCalc bottomCalc = call.rel(0); + FlinkLogicalCalc middleCalc = call.rel(1); + FlinkLogicalCalc topCalc = call.rel(2); + return isChainedRowBasedPythonFunction(bottomCalc, middleCalc, topCalc); + } + + private boolean isChainedRowBasedPythonFunction( + FlinkLogicalCalc bottomCalc, FlinkLogicalCalc middleCalc, FlinkLogicalCalc topCalc) { + RexProgram bottomProgram = bottomCalc.getProgram(); + List<RexNode> bottomProjects = bottomProgram.getProjectList() + .stream() + .map(bottomProgram::expandLocalRef) + .collect(Collectors.toList()); + + if (bottomProjects.size() != 1 || PythonUtil.isNonPythonCall(bottomProjects.get(0))) { + return false; + } + + RexProgram topProgram = topCalc.getProgram(); + List<RexNode> topProjects = topProgram.getProjectList() + .stream() + .map(topProgram::expandLocalRef) + .collect(Collectors.toList()); + if (topProjects.size() != 1 || PythonUtil.isNonPythonCall(topProjects.get(0))) { + return false; + } + + RexProgram middleProgram = middleCalc.getProgram(); + List<RexNode> middleProjects = middleProgram.getProjectList() + .stream() + .map(middleProgram::expandLocalRef) + .collect(Collectors.toList()); + + return isInputsCorrespondWithUpstreamOutputs(bottomProjects, middleProjects) && + isFlattenCalc(middleProjects); + } + + private boolean isInputsCorrespondWithUpstreamOutputs(List<RexNode> bottomProjects, List<RexNode> middleProjects) { + RexCall pythonCall = (RexCall) bottomProjects.get(0); + List<RexNode> pythonCallInputs = pythonCall.getOperands(); + if (pythonCallInputs.size() != middleProjects.size()) { + return false; + } + for (int i = 0; i < pythonCallInputs.size(); i++) { + RexNode input = pythonCallInputs.get(i); + if (input instanceof RexInputRef) { + if (((RexInputRef) input).getIndex() != i) { + return false; + } + } else { + return false; + } + } + return true; + } + + private boolean isFlattenCalc(List<RexNode> middleProjects) { + for (RexNode middleProject : middleProjects) { + if (middleProject instanceof RexFieldAccess) { + RexNode expr = ((RexFieldAccess) middleProject).getReferenceExpr(); + if (expr instanceof RexInputRef) { + if (((RexInputRef) expr).getIndex() != 0) { Review comment: Yes. Good Catch. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
