Make SupportsDelete to be simple mix-in of DSV2

Author: xy_xin

sql/catalyst/src/main/java/org/apache/spark/sql/sources/v2/SupportsDelete.java

@@ -0,0 +1,39 @@
+/*
+ * 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.spark.sql.sources.v2;
+
+import org.apache.spark.sql.sources.Filter;
+
+public interface SupportsDelete {
+  /**
+   * Delete data from a data source table that matches filter expressions.
+   * <p>
+   * Rows are deleted from the data source iff all of the filter expressions match. That is, the
+   * expressions must be interpreted as a set of filters that are ANDed together.
+   * <p>
+   * Implementations may reject a delete operation if the delete isn't possible without significant
+   * effort. For example, partitioned data sources may reject deletes that do not filter by
+   * partition columns because the filter may require rewriting files without deleted records.
+   * To reject a delete implementations should throw {@link IllegalArgumentException} with a clear
+   * error message that identifies which expression was rejected.
+   *
+   * @param filters filter expressions, used to select rows to delete when all expressions match
+   * @throws IllegalArgumentException If the delete is rejected due to required effort
+   */
+  void deleteWhere(Filter[] filters);
+}

sql/catalyst/src/main/java/org/apache/spark/sql/sources/v2/SupportsMaintenance.java

@@ -40,12 +40,12 @@ object DataSourceV2Implicits {
       }
     }
 
-    def asMaintainable: SupportsMaintenance = {
+    def asDeletable: SupportsDelete = {
       table match {
-        case support: SupportsMaintenance =>
+        case support: SupportsDelete =>
           support
         case _ =>
-          throw new AnalysisException(s"Table does not support maintenance: ${table.name}")
+          throw new AnalysisException(s"Table does not support deletes: ${table.name}")
       }
     }
 

sql/catalyst/src/main/java/org/apache/spark/sql/sources/v2/maintain/Maintainer.java

@@ -23,8 +23,7 @@ import scala.collection.mutable
 import org.apache.spark.sql.{AnalysisException, Strategy}
 import org.apache.spark.sql.catalyst.expressions.{And, AttributeReference, AttributeSet, Expression, PredicateHelper, SubqueryExpression}
 import org.apache.spark.sql.catalyst.planning.PhysicalOperation
-import org.apache.spark.sql.catalyst.plans.logical.{AlterTable, AppendData, CreateTableAsSelect, CreateV2Table, DropTable, LogicalPlan, OverwriteByExpression, OverwritePartitionsDynamic, Repartition}
-import org.apache.spark.sql.catalyst.plans.logical._
+import org.apache.spark.sql.catalyst.plans.logical.{AlterTable, AppendData, CreateTableAsSelect, CreateV2Table, DeleteFromTable, DropTable, LogicalPlan, OverwriteByExpression, OverwritePartitionsDynamic, Repartition}
 import org.apache.spark.sql.execution.{FilterExec, ProjectExec, SparkPlan}
 import org.apache.spark.sql.execution.datasources.{DataSourceStrategy, LogicalRelation}
 import org.apache.spark.sql.execution.streaming.continuous.{ContinuousCoalesceExec, WriteToContinuousDataSource, WriteToContinuousDataSourceExec}
@@ -191,7 +190,7 @@ object DataSourceV2Strategy extends Strategy with PredicateHelper {
         filter => DataSourceStrategy.translateFilter(deleteExpr).getOrElse(
           throw new AnalysisException(s"Cannot translate expression to source filter: $filter"))
       }.toArray
-      DeleteFromTableExec(r.table.asMaintainable, r.options, filters, planLater(r)) :: Nil
+      DeleteFromTableExec(r.table.asDeletable, r.options, filters, planLater(r)) :: Nil
 
     case WriteToContinuousDataSource(writer, query) =>
       WriteToContinuousDataSourceExec(writer, planLater(query)) :: Nil

sql/catalyst/src/main/java/org/apache/spark/sql/sources/v2/maintain/MaintainerBuilder.java

@@ -17,30 +17,23 @@
 
 package org.apache.spark.sql.execution.datasources.v2
 
-import org.apache.spark.SparkException
 import org.apache.spark.rdd.RDD
 import org.apache.spark.sql.catalyst.InternalRow
 import org.apache.spark.sql.catalyst.expressions.Attribute
 import org.apache.spark.sql.execution.{SparkPlan, UnaryExecNode}
 import org.apache.spark.sql.sources.Filter
-import org.apache.spark.sql.sources.v2.SupportsMaintenance
-import org.apache.spark.sql.sources.v2.maintain.SupportsDelete
+import org.apache.spark.sql.sources.v2.SupportsDelete
 import org.apache.spark.sql.util.CaseInsensitiveStringMap
 
 case class DeleteFromTableExec(
-    table: SupportsMaintenance,
+    table: SupportsDelete,
     options: CaseInsensitiveStringMap,
     deleteWhere: Array[Filter],
     query: SparkPlan) extends UnaryExecNode {
 
   override protected def doExecute(): RDD[InternalRow] = {
-    table.newMaintainerBuilder(options).build() match {
-      case maintainer: SupportsDelete =>
-        maintainer.delete(deleteWhere)
-      case _ =>
-        throw new SparkException(s"Table does not support delete: $table")
-    }
 
+    table.deleteWhere(deleteWhere)
     sparkContext.emptyRDD
   }
 

sql/catalyst/src/main/java/org/apache/spark/sql/sources/v2/maintain/SupportsDelete.java

@@ -26,7 +26,6 @@ import org.apache.spark.sql.{Column, SparkSession}
 import org.apache.spark.sql.catalyst.InternalRow
 import org.apache.spark.sql.catalyst.expressions.{EqualNullSafe, Literal, Not}
 import org.apache.spark.sql.sources.Filter
-import org.apache.spark.sql.sources.v2.maintain.{Maintainer, MaintainerBuilder, SupportsDelete}
 import org.apache.spark.sql.sources.v2.reader._
 import org.apache.spark.sql.sources.v2.writer._
 import org.apache.spark.sql.types._
@@ -41,7 +40,7 @@ private[v2] class InMemoryTable(
     val name: String,
     val schema: StructType,
     override val properties: util.Map[String, String])
-    extends Table with SupportsRead with SupportsWrite with SupportsMaintenance {
+    extends Table with SupportsRead with SupportsWrite with SupportsDelete {
 
   def this(
       name: String,
@@ -92,26 +91,6 @@ private[v2] class InMemoryTable(
     }
   }
 
-  override def newMaintainerBuilder(options: CaseInsensitiveStringMap): MaintainerBuilder = {
-    () => {
-      Delete
-    }
-  }
-
-  private object Delete extends Maintainer with SupportsDelete {
-
-    override def delete(filters: Array[Filter]): Unit = {
-      val filtered = data.map {
-        rows =>
-          val newRows = filter(rows.rows, filters)
-          val newBufferedRows = new BufferedRows()
-          newBufferedRows.rows.appendAll(newRows)
-          newBufferedRows
-      }.filter(_.rows.nonEmpty)
-      replaceData(filtered)
-    }
-  }
-
   def filter(rows: mutable.ArrayBuffer[InternalRow],
       filters: Array[Filter]): Array[InternalRow] = {
     if (rows.isEmpty) {
@@ -164,6 +143,17 @@ private[v2] class InMemoryTable(
     override def abort(messages: Array[WriterCommitMessage]): Unit = {
     }
   }
+
+  override def deleteWhere(filters: Array[Filter]): Unit = {
+    val filtered = data.map {
+      rows =>
+        val newRows = filter(rows.rows, filters)
+        val newBufferedRows = new BufferedRows()
+        newBufferedRows.rows.appendAll(newRows)
+        newBufferedRows
+    }.filter(_.rows.nonEmpty)
+    replaceData(filtered)
+  }
 }
 
 private class BufferedRows extends WriterCommitMessage with InputPartition with Serializable {