itsvikramagr commented on a change in pull request #24922: [SPARK-28120][SS] Rocksdb state storage implementation URL: https://github.com/apache/spark/pull/24922#discussion_r297004509
########## File path: sql/core/src/main/scala/org/apache/spark/sql/execution/streaming/state/WALUtils.scala ########## @@ -0,0 +1,286 @@ +/* + * 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.io._ +import java.util.Locale + +import com.google.common.io.ByteStreams +import org.apache.commons.io.IOUtils +import org.apache.hadoop.fs.{FileStatus, FSDataInputStream, FSError, Path} +import scala.collection.mutable + +import org.apache.spark.SparkConf +import org.apache.spark.io.LZ4CompressionCodec +import org.apache.spark.sql.catalyst.expressions.UnsafeRow +import org.apache.spark.sql.execution.streaming.CheckpointFileManager +import org.apache.spark.sql.execution.streaming.CheckpointFileManager.CancellableFSDataOutputStream +import org.apache.spark.sql.types.StructType + + +object WALUtils { + + case class StoreFile(version: Long, path: Path, isSnapshot: Boolean) + + /** Files needed to recover the given version of the store */ + def filesForVersion(allFiles: Seq[StoreFile], version: Long): Seq[StoreFile] = { + require(version >= 0) + require(allFiles.exists(_.version == version)) + + val latestSnapshotFileBeforeVersion = allFiles + .filter(_.isSnapshot == true) + .takeWhile(_.version <= version) + .lastOption + val deltaBatchFiles = latestSnapshotFileBeforeVersion match { + case Some(snapshotFile) => + + val deltaFiles = allFiles.filter { file => + file.version > snapshotFile.version && file.version <= version + }.toList + verify( + deltaFiles.size == version - snapshotFile.version, + s"Unexpected list of delta files for version $version for $this: $deltaFiles" + ) + deltaFiles + + case None => + allFiles.takeWhile(_.version <= version) + } + latestSnapshotFileBeforeVersion.toSeq ++ deltaBatchFiles + } + + /** Fetch all the files that back the store */ + def fetchFiles(fm: CheckpointFileManager, baseDir: Path): Seq[StoreFile] = { + val files: Seq[FileStatus] = try { + fm.list(baseDir) + } catch { + case _: java.io.FileNotFoundException => + Seq.empty + } + val versionToFiles = new mutable.HashMap[Long, StoreFile] + files.foreach { status => + val path = status.getPath + val nameParts = path.getName.split("\\.") + if (nameParts.size == 2) { + val version = nameParts(0).toLong + nameParts(1).toLowerCase(Locale.ROOT) match { + case "delta" => + // ignore the file otherwise, snapshot file already exists for that batch id + if (!versionToFiles.contains(version)) { + versionToFiles.put(version, StoreFile(version, path, isSnapshot = false)) + } + case "snapshot" => + versionToFiles.put(version, StoreFile(version, path, isSnapshot = true)) + case _ => + // logWarning(s"Could not identify file $path for $this") + } + } + } + val storeFiles = versionToFiles.values.toSeq.sortBy(_.version) + // logDebug(s"Current set of files for $this: ${storeFiles.mkString(", ")}") + storeFiles + } + + def compressStream(outputStream: DataOutputStream, sparkConf: SparkConf): DataOutputStream = { + val compressed = new LZ4CompressionCodec(sparkConf).compressedOutputStream(outputStream) + new DataOutputStream(compressed) + } + + def decompressStream(inputStream: DataInputStream, sparkConf: SparkConf): DataInputStream = { + val compressed = new LZ4CompressionCodec(sparkConf).compressedInputStream(inputStream) + new DataInputStream(compressed) + } + + + def writeUpdateToDeltaFile( + output: DataOutputStream, + key: UnsafeRow, + value: UnsafeRow): Unit = { + val keyBytes = key.getBytes() + val valueBytes = value.getBytes() + output.writeInt(keyBytes.size) + output.write(keyBytes) + output.writeInt(valueBytes.size) + output.write(valueBytes) + } + + def writeRemoveToDeltaFile(output: DataOutputStream, key: UnsafeRow): Unit = { + val keyBytes = key.getBytes() + output.writeInt(keyBytes.size) + output.write(keyBytes) + output.writeInt(-1) + } + + def finalizeDeltaFile(output: DataOutputStream): Unit = { + output.writeInt(-1) // Write this magic number to signify end of file + output.close() + } + + def updateFromDeltaFile( fm: CheckpointFileManager, + fileToRead: Path, + keySchema: StructType, + valueSchema: StructType, + newRocksDb: OptimisticTransactionDbInstance, + sparkConf: SparkConf): Unit = { + var input: DataInputStream = null + val sourceStream = try { + fm.open(fileToRead) + } catch { + case f: FileNotFoundException => + throw new IllegalStateException( + s"Error reading delta file $fileToRead of $this: $fileToRead does not exist", f) + } + try { + input = decompressStream(sourceStream, sparkConf) + var eof = false + + while(!eof) { + val keySize = input.readInt() + if (keySize == -1) { + eof = true + } else if (keySize < 0) { + newRocksDb.abort + newRocksDb.close() + throw new IOException( + s"Error reading delta file $fileToRead of $this: key size cannot be $keySize") + } else { + val keyRowBuffer = new Array[Byte](keySize) + ByteStreams.readFully(input, keyRowBuffer, 0, keySize) + + val keyRow = new UnsafeRow(keySchema.fields.length) + keyRow.pointTo(keyRowBuffer, keySize) + + val valueSize = input.readInt() + if (valueSize < 0) { + newRocksDb.remove(key = keyRow) + } else { + val valueRowBuffer = new Array[Byte](valueSize) + ByteStreams.readFully(input, valueRowBuffer, 0, valueSize) + val valueRow = new UnsafeRow(valueSchema.fields.length) + // If valueSize in existing file is not multiple of 8, floor it to multiple of 8. + // This is a workaround for the following: + // Prior to Spark 2.3 mistakenly append 4 bytes to the value row in + // `RowBasedKeyValueBatch`, which gets persisted into the checkpoint data + valueRow.pointTo(valueRowBuffer, (valueSize / 8) * 8) + newRocksDb.put(keyRow, valueRow) + } + } + } + } finally { + if (input != null) input.close() + } + } + + /* + * Try to cancel the underlying stream and safely close the compressed stream. + * + * @param compressedStream the compressed stream. + * @param rawStream the underlying stream which needs to be cancelled. + */ + def cancelDeltaFile( + compressedStream: DataOutputStream, Review comment: Ran ./dev/scalafmt now to fix all indentation issues. Missed to run it before raising the PR ---------------------------------------------------------------- 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 With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
