hequn8128 commented on a change in pull request #9748: [FLINK-14016][python][flink-table-planner] Introduce DataStreamPythonCalc for Python function execution URL: https://github.com/apache/flink/pull/9748#discussion_r328408371
########## File path: flink-table/flink-table-planner/src/main/scala/org/apache/flink/table/plan/rules/logical/PythonScalarFunctionSplitRule.scala ########## @@ -0,0 +1,211 @@ +/* + * 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.plan.rules.logical + +import org.apache.calcite.plan.RelOptRule.{any, operand} +import org.apache.calcite.plan.{RelOptRule, RelOptRuleCall} +import org.apache.calcite.rex.{RexCall, RexInputRef, RexNode, RexProgram} +import org.apache.calcite.sql.validate.SqlValidatorUtil +import org.apache.flink.table.functions.FunctionLanguage +import org.apache.flink.table.functions.ScalarFunction +import org.apache.flink.table.functions.utils.ScalarSqlFunction +import org.apache.flink.table.plan.nodes.logical.FlinkLogicalCalc +import org.apache.flink.table.plan.util.PythonUtil.containsFunctionOf +import org.apache.flink.table.plan.util.{InputRefVisitor, RexDefaultVisitor} +import org.apache.flink.table.plan.rules.logical.PythonScalarFunctionSplitRule.extractRefInputFields + +import scala.collection.JavaConverters._ +import scala.collection.JavaConversions._ +import scala.collection.mutable + +/** + * Rule that splits [[FlinkLogicalCalc]] into multiple [[FlinkLogicalCalc]]s. After this rule + * is applied, each [[FlinkLogicalCalc]] will only contain Python [[ScalarFunction]]s or Java + * [[ScalarFunction]]s. This is to ensure that the Python [[ScalarFunction]]s which could be + * executed in a batch are grouped into the same [[FlinkLogicalCalc]] node. + */ +class PythonScalarFunctionSplitRule extends RelOptRule( + operand(classOf[FlinkLogicalCalc], any), + "PythonScalarFunctionSplitRule") { + + override def matches(call: RelOptRuleCall): Boolean = { + val calc: FlinkLogicalCalc = call.rel(0).asInstanceOf[FlinkLogicalCalc] + val program = calc.getProgram + program.getExprList.exists(containsFunctionOf(_, FunctionLanguage.PYTHON)) && + program.getExprList.exists(containsFunctionOf(_, FunctionLanguage.JVM)) + } + + override def onMatch(call: RelOptRuleCall): Unit = { + val calc: FlinkLogicalCalc = call.rel(0).asInstanceOf[FlinkLogicalCalc] + val input = calc.getInput + val rexBuilder = call.builder().getRexBuilder + val program = calc.getProgram + val extractedRexCalls = new mutable.ArrayBuffer[RexCall]() + + val outerCallContainsJavaFunction = + program.getProjectList + .map(program.expandLocalRef) + .exists(containsFunctionOf(_, FunctionLanguage.JVM, recursive = false)) || + Option(program.getCondition) + .map(program.expandLocalRef) + .exists(containsFunctionOf(_, FunctionLanguage.JVM, recursive = false)) + + val extractedFunctionOffset = input.getRowType.getFieldCount + val splitter = new ScalarFunctionSplitter( + extractedFunctionOffset, + extractedRexCalls, + outerCallContainsJavaFunction) + + val newProjects = program.getProjectList + .map(program.expandLocalRef) + .map(_.accept(splitter)) + + val newCondition = Option(program.getCondition) + .map(program.expandLocalRef) + .map(_.accept(splitter)) + + val accessedFields = extractRefInputFields( + newProjects, newCondition, extractedFunctionOffset) + + val bottomCalcProjects = + accessedFields.map(RexInputRef.of(_, input.getRowType)) ++ extractedRexCalls + val bottomCalcFieldNames = SqlValidatorUtil.uniquify( + accessedFields.map(i => input.getRowType.getFieldNames.get(i)).toSeq ++ + extractedRexCalls.indices.map("f" + _), + rexBuilder.getTypeFactory.getTypeSystem.isSchemaCaseSensitive) + + val bottomCalc = new FlinkLogicalCalc( + calc.getCluster, + calc.getTraitSet, + input, + RexProgram.create( + input.getRowType, + bottomCalcProjects.toList, + null, + bottomCalcFieldNames, + rexBuilder)) + + val inputRewriter = new ExtractedFunctionInputRewriter( + extractedFunctionOffset, accessedFields) + val topCalc = new FlinkLogicalCalc( + calc.getCluster, + calc.getTraitSet, + bottomCalc, + RexProgram.create( + bottomCalc.getRowType, + newProjects.map(_.accept(inputRewriter)), + newCondition.map(_.accept(inputRewriter)).orNull, + calc.getRowType, + rexBuilder)) + + call.transformTo(topCalc) + } +} + +private class ScalarFunctionSplitter( + extractedFunctionOffset: Int, + extractedRexCalls: mutable.ArrayBuffer[RexCall], + convertPythonFunction: Boolean) + extends RexDefaultVisitor[RexNode] { + + override def visitCall(call: RexCall): RexNode = { + call.getOperator match { + case sfc: ScalarSqlFunction if sfc.getScalarFunction.getLanguage == + FunctionLanguage.PYTHON => + visit(convertPythonFunction, call) + + case _ => + visit(!convertPythonFunction, call) + } + } + + override def visitNode(rexNode: RexNode): RexNode = rexNode + + private def visit(needConvert: Boolean, call: RexCall): RexNode = { + if (needConvert) { + val newNode = new RexInputRef( + extractedFunctionOffset + extractedRexCalls.length, call.getType) + extractedRexCalls.append(call) + newNode + } else { + call.clone(call.getType, call.getOperands.asScala.map(_.accept(this))) + } + } +} + +/** + * Rewrite field accesses of a RexNode as not all the fields from the original input are forwarded: + * 1) Fields of index greater than or equal to extractedFunctionOffset refer to the + * extracted function. + * 2) Fields of index less than extractedFunctionOffset refer to the original input field. + * + * @param extractedFunctionOffset the original start offset of the extracted functions + * @param accessedFields the accessed fields which will be forwarded + */ +class ExtractedFunctionInputRewriter( + extractedFunctionOffset: Int, + accessedFields: Array[Int]) + extends RexDefaultVisitor[RexNode] { + + /** old input fields ref index -> new input fields ref index mappings */ + private val fieldMap: Map[Int, Int] = accessedFields.zipWithIndex.toMap + + override def visitInputRef(inputRef: RexInputRef): RexNode = { + if (inputRef.getIndex >= extractedFunctionOffset) { + new RexInputRef( + inputRef.getIndex - extractedFunctionOffset + accessedFields.length, + inputRef.getType) + } else { + new RexInputRef( + fieldMap.getOrElse(inputRef.getIndex, + throw new IllegalArgumentException("input field contains invalid index")), + inputRef.getType) + } + } + + override def visitCall(call: RexCall): RexNode = { + call.clone(call.getType, call.getOperands.asScala.map(_.accept(this))) + } + + override def visitNode(rexNode: RexNode): RexNode = rexNode +} + +object PythonScalarFunctionSplitRule { + val INSTANCE: RelOptRule = new PythonScalarFunctionSplitRule + + /** + * Extracts the indices of the input fields referred by the specified projects and condition. + */ + def extractRefInputFields( Review comment: Put this method into the `PythonScalarFunctionSplitRule` class and make it private? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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