org.apache.flink.table.planner.plan.nodes.logical.FlinkLogicalLegacyTableSourceScan.scala Maven / Gradle / Ivy

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 * 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
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package org.apache.flink.table.planner.plan.nodes.logical

import org.apache.flink.table.planner.plan.nodes.FlinkConventions
import org.apache.flink.table.planner.plan.nodes.logical.FlinkLogicalLegacyTableSourceScan.isTableSourceScan
import org.apache.flink.table.planner.plan.schema.{FlinkPreparingTableBase, LegacyTableSourceTable}
import org.apache.flink.table.sources._

import com.google.common.collect.ImmutableList
import org.apache.calcite.plan._
import org.apache.calcite.rel.`type`.RelDataType
import org.apache.calcite.rel.convert.ConverterRule
import org.apache.calcite.rel.core.TableScan
import org.apache.calcite.rel.hint.RelHint
import org.apache.calcite.rel.logical.LogicalTableScan
import org.apache.calcite.rel.metadata.RelMetadataQuery
import org.apache.calcite.rel.{RelCollation, RelCollationTraitDef, RelNode, RelWriter}

import java.util
import java.util.Collections
import java.util.function.Supplier

/**
  * Sub-class of [[TableScan]] that is a relational operator
  * which returns the contents of a [[TableSource]] in Flink.
  */
class FlinkLogicalLegacyTableSourceScan(
    cluster: RelOptCluster,
    traitSet: RelTraitSet,
    relOptTable: LegacyTableSourceTable[_])
  extends TableScan(cluster, traitSet, Collections.emptyList[RelHint](), relOptTable)
  with FlinkLogicalRel {

  lazy val tableSource: TableSource[_] = tableSourceTable.tableSource

  private lazy val tableSourceTable = relOptTable.unwrap(classOf[LegacyTableSourceTable[_]])

  def copy(
      traitSet: RelTraitSet,
      tableSourceTable: LegacyTableSourceTable[_]): FlinkLogicalLegacyTableSourceScan = {
    new FlinkLogicalLegacyTableSourceScan(cluster, traitSet, tableSourceTable)
  }

  override def copy(traitSet: RelTraitSet, inputs: java.util.List[RelNode]): RelNode = {
    new FlinkLogicalLegacyTableSourceScan(cluster, traitSet, relOptTable)
  }

  override def deriveRowType(): RelDataType = {
    // TableScan row type should always keep same with its
    // interval RelOptTable's row type.
    relOptTable.getRowType
  }

  override def computeSelfCost(planner: RelOptPlanner, mq: RelMetadataQuery): RelOptCost = {
    val rowCnt = mq.getRowCount(this)
    val rowSize = mq.getAverageRowSize(this)
    planner.getCostFactory.makeCost(rowCnt, rowCnt, rowCnt * rowSize)
  }

  override def explainTerms(pw: RelWriter): RelWriter = {
    super.explainTerms(pw)
      .item("fields", tableSource.getTableSchema.getFieldNames.mkString(", "))
  }

}

class FlinkLogicalLegacyTableSourceScanConverter
  extends ConverterRule(
    classOf[LogicalTableScan],
    Convention.NONE,
    FlinkConventions.LOGICAL,
    "FlinkLogicalLegacyTableSourceScanConverter") {

  override def matches(call: RelOptRuleCall): Boolean = {
    val scan: TableScan = call.rel(0)
    isTableSourceScan(scan)
  }

  def convert(rel: RelNode): RelNode = {
    val scan = rel.asInstanceOf[TableScan]
    val table = scan.getTable.asInstanceOf[FlinkPreparingTableBase]
    FlinkLogicalLegacyTableSourceScan.create(rel.getCluster, table)
  }
}

object FlinkLogicalLegacyTableSourceScan {
  val CONVERTER = new FlinkLogicalLegacyTableSourceScanConverter

  def isTableSourceScan(scan: TableScan): Boolean = {
    val tableSourceTable = scan.getTable.unwrap(classOf[LegacyTableSourceTable[_]])
    tableSourceTable != null
  }

  def create(cluster: RelOptCluster, relOptTable: FlinkPreparingTableBase)
      : FlinkLogicalLegacyTableSourceScan = {
    val table = relOptTable.unwrap(classOf[LegacyTableSourceTable[_]])
    val traitSet = cluster.traitSetOf(FlinkConventions.LOGICAL).replaceIfs(
      RelCollationTraitDef.INSTANCE, new Supplier[util.List[RelCollation]]() {
        def get: util.List[RelCollation] = {
          if (table != null) {
            table.getStatistic.getCollations
          } else {
            ImmutableList.of[RelCollation]
          }
        }
      }).simplify()
    new FlinkLogicalLegacyTableSourceScan(cluster, traitSet, table)
  }
}