zifeif2 commented on code in PR #53703: URL: https://github.com/apache/spark/pull/53703#discussion_r2666698849
########## sql/core/src/main/scala/org/apache/spark/sql/execution/streaming/state/StateRewriter.scala: ########## @@ -0,0 +1,373 @@ +/* + * 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.execution.streaming.state + +import java.util.UUID + +import org.apache.hadoop.conf.Configuration +import org.apache.hadoop.fs.Path + +import org.apache.spark.{SparkIllegalStateException, TaskContext} +import org.apache.spark.internal.Logging +import org.apache.spark.internal.LogKeys._ +import org.apache.spark.sql.DataFrame +import org.apache.spark.sql.SparkSession +import org.apache.spark.sql.execution.datasources.v2.state.StateSourceOptions +import org.apache.spark.sql.execution.datasources.v2.state.metadata.StateMetadataPartitionReader +import org.apache.spark.sql.execution.streaming.checkpointing.OffsetSeqMetadata +import org.apache.spark.sql.execution.streaming.operators.stateful.StatefulOperatorsUtils +import org.apache.spark.sql.execution.streaming.operators.stateful.transformwithstate.{StateVariableType, TransformWithStateOperatorProperties, TransformWithStateVariableInfo} +import org.apache.spark.sql.execution.streaming.runtime.{StreamingCheckpointConstants, StreamingQueryCheckpointMetadata} +import org.apache.spark.sql.execution.streaming.state.{StatePartitionAllColumnFamiliesWriter, StateSchemaCompatibilityChecker} +import org.apache.spark.sql.internal.SQLConf +import org.apache.spark.util.SerializableConfiguration + +/** + * State Rewriter is used to rewrite the state stores for a stateful streaming query. + * It reads state from a checkpoint location, optionally applies transformation to the state, + * and then writes the state back to a (possibly different) checkpoint location for a new batch ID. + * + * Example use case is for offline state repartitioning. + * Can also be used to support state rewind and other use cases. + * + * @param sparkSession The active Spark session. + * @param readBatchId The batch ID for reading state. + * @param writeBatchId The batch ID to which the (transformed) state will be written. + * @param resolvedCheckpointLocation The resolved checkpoint path where state will be written. + * @param hadoopConf Hadoop configuration for file system operations. + * @param readResolvedCheckpointLocation Optional separate checkpoint location to read state from. + * If None, reads from resolvedCheckpointLocation. + * @param transformFunc Optional transformation function applied to each operator's state + * DataFrame. If None, state is written as-is. + * @param writeCheckpointMetadata Optional checkpoint metadata for the resolvedCheckpointLocation. + * If None, will create a new one for resolvedCheckpointLocation. + * Helps us to reuse already cached checkpoint log entries, + * instead of starting from scratch. + */ +class StateRewriter( + sparkSession: SparkSession, + readBatchId: Long, + writeBatchId: Long, + resolvedCheckpointLocation: String, + hadoopConf: Configuration, + readResolvedCheckpointLocation: Option[String] = None, + transformFunc: Option[DataFrame => DataFrame] = None, + writeCheckpointMetadata: Option[StreamingQueryCheckpointMetadata] = None +) extends Logging { + require(readResolvedCheckpointLocation.isDefined || readBatchId < writeBatchId, + s"Read batch id $readBatchId must be less than write batch id $writeBatchId " + + "when reading and writing to the same checkpoint location") + + // If a different location was specified for reading state, use it. + // Else, use same location for reading and writing state. + private val checkpointLocationForRead = + readResolvedCheckpointLocation.getOrElse(resolvedCheckpointLocation) + private val stateRootLocation = new Path( + resolvedCheckpointLocation, StreamingCheckpointConstants.DIR_NAME_STATE).toString + + def run(): Unit = { Review Comment: Though writer doesn't support checkpointV2 yet, do we still want to return `StateStoreCheckpointInfo` to unblock rewind/replay? -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
