Github user rxin commented on a diff in the pull request:
https://github.com/apache/spark/pull/15731#discussion_r86087278
--- Diff:
core/src/main/scala/org/apache/spark/internal/io/FileCommitProtocol.scala ---
@@ -0,0 +1,131 @@
+/*
+ * 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.internal.io
+
+import org.apache.hadoop.mapreduce._
+
+import org.apache.spark.util.Utils
+
+
+/**
+ * An interface to define how a single Spark job commits its outputs. Two
notes:
+ *
+ * 1. Implementations must be serializable, as the committer instance
instantiated on the driver
+ * will be used for tasks on executors.
+ * 2. Implementations should have a constructor with either 2 or 3
arguments:
+ * (jobId: String, path: String) or (jobId: String, path: String,
isAppend: Boolean).
+ * 3. A committer should not be reused across multiple Spark jobs.
+ *
+ * The proper call sequence is:
+ *
+ * 1. Driver calls setupJob.
+ * 2. As part of each task's execution, executor calls setupTask and then
commitTask
+ * (or abortTask if task failed).
+ * 3. When all necessary tasks completed successfully, the driver calls
commitJob. If the job
+ * failed to execute (e.g. too many failed tasks), the job should call
abortJob.
+ */
+abstract class FileCommitProtocol {
+ import FileCommitProtocol._
+
+ /**
+ * Setups up a job. Must be called on the driver before any other
methods can be invoked.
+ */
+ def setupJob(jobContext: JobContext): Unit
+
+ /**
+ * Commits a job after the writes succeed. Must be called on the driver.
+ */
+ def commitJob(jobContext: JobContext, taskCommits:
Seq[TaskCommitMessage]): Unit
+
+ /**
+ * Aborts a job after the writes fail. Must be called on the driver.
+ *
+ * Calling this function is a best-effort attempt, because it is
possible that the driver
+ * just crashes (or killed) before it can call abort.
+ */
+ def abortJob(jobContext: JobContext): Unit
+
+ /**
+ * Sets up a task within a job.
+ * Must be called before any other task related methods can be invoked.
+ */
+ def setupTask(taskContext: TaskAttemptContext): Unit
+
+ /**
+ * Notifies the commit protocol to add a new file, and gets back the
full path that should be
+ * used. Must be called on the executors when running tasks.
+ *
+ * Note that the returned temp file may have an arbitrary path. The
commit protocol only
+ * promises that the file will be at the location specified by the
arguments after job commit.
+ *
+ * A full file path consists of the following parts:
+ * 1. the base path
+ * 2. some sub-directory within the base path, used to specify
partitioning
+ * 3. file prefix, usually some unique job id with the task id
+ * 4. bucket id
+ * 5. source specific file extension, e.g. ".snappy.parquet"
+ *
+ * The "dir" parameter specifies 2, and "ext" parameter specifies both 4
and 5, and the rest
+ * are left to the commit protocol implementation to decide.
+ */
+ def newTaskTempFile(taskContext: TaskAttemptContext, dir:
Option[String], ext: String): String
+
+ /**
+ * Commits a task after the writes succeed. Must be called on the
executors when running tasks.
+ */
+ def commitTask(taskContext: TaskAttemptContext): TaskCommitMessage
+
+ /**
+ * Aborts a task after the writes have failed. Must be called on the
executors when running tasks.
+ *
+ * Calling this function is a best-effort attempt, because it is
possible that the executor
+ * just crashes (or killed) before it can call abort.
+ */
+ def abortTask(taskContext: TaskAttemptContext): Unit
+}
+
+
+object FileCommitProtocol {
+ class TaskCommitMessage(val obj: Any) extends Serializable
+
+ object EmptyTaskCommitMessage extends TaskCommitMessage(null)
+
+ /**
+ * Instantiates a FileCommitProtocol using the given className.
+ */
+ def instantiate(className: String, jobId: String, outputPath: String,
isAppend: Boolean)
--- End diff --
the main change here is the introduction of a "jobId".
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
