org.elasticsearch.spark.sql.streaming.EsCommitProtocol.scala Maven / Gradle / Ivy
package org.elasticsearch.spark.sql.streaming
import org.apache.commons.logging.Log
import org.apache.commons.logging.LogFactory
import org.apache.spark.sql.execution.streaming.MetadataLog
import org.elasticsearch.hadoop.util.Assert
/**
* Defines job-side and task-side logic for committing batches of writes
* to Elasticsearch for Spark Structured Streaming
*/
class EsCommitProtocol(@transient val commitLog: MetadataLog[Array[EsSinkStatus]]) extends Serializable {
@transient lazy val logger: Log = LogFactory.getLog(classOf[EsCommitProtocol])
/**
* Prepare the driver side of the commit protocol.
* @param jobState the current Job information
*/
def initJob(jobState: JobState): Unit = {
Assert.notNull(commitLog, "commitLog cannot be null")
}
/**
* Commit the results of each of the tasks to the execution log.
* @param jobState the current Job information
* @param taskCommits the results from each of the tasks
*/
def commitJob(jobState: JobState, taskCommits: Seq[TaskCommit]): Unit = {
val commits = taskCommits.flatMap(_.statuses).toArray[EsSinkStatus]
if (commitLog.add(jobState.batchId, commits)) {
logger.debug(s"Committed batch ${jobState.batchId}")
} else {
throw new IllegalStateException(s"Batch Id [${jobState.batchId}] is already committed")
}
}
/**
* Abort this job execution.
* @param jobState the current Job information
*/
def abortJob(jobState: JobState): Unit = {
// Nothing to do, here for extension if needed
}
@transient var recordsWritten: Long = _
@transient var executionStart: Long = _
/**
* Initialize the executor side of the commit protocol.
* @param taskState the current Task information
*/
def initTask(taskState: TaskState): Unit = {
recordsWritten = 0L
executionStart = System.currentTimeMillis()
}
/**
* Signal that a record has been processed in this transaction.
*/
def recordSeen(): Unit = {
recordsWritten = recordsWritten + 1
}
/**
* Commit this task's transaction.
* @param taskState the current Task information
* @return a summary of this Task's actions as a commit message to be added to the log
*/
def commitTask(taskState: TaskState): TaskCommit = {
if (recordsWritten > 0) {
TaskCommit(Some(EsSinkStatus(taskState.taskId, executionStart, taskState.resource, recordsWritten)))
} else {
TaskCommit(None)
}
}
/**
* Abort this task execution
* @param taskState the current Task information
*/
def abortTask(taskState: TaskState): Unit = {
// Nothing to do, here for extension if needed
}
}
// Envelope classes for the commit protocol
case class JobState(jobId: String, batchId: Long)
case class TaskState(taskId: Int, resource: String)
case class TaskCommit(statuses: Option[EsSinkStatus])