org.apache.flink.runtime.state.memory.PersistentMetadataCheckpointStorageLocation Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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*/
package org.apache.flink.runtime.state.memory;
import org.apache.flink.core.fs.FileSystem;
import org.apache.flink.core.fs.Path;
import org.apache.flink.runtime.state.CheckpointMetadataOutputStream;
import org.apache.flink.runtime.state.CheckpointStorageLocation;
import org.apache.flink.runtime.state.CheckpointStorageLocationReference;
import org.apache.flink.runtime.state.filesystem.AbstractFsCheckpointStorage;
import org.apache.flink.runtime.state.filesystem.FsCheckpointMetadataOutputStream;
import java.io.IOException;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* A checkpoint storage location for the {@link MemoryStateBackend} when it durably
* persists the metadata in a file system.
*/
public class PersistentMetadataCheckpointStorageLocation
extends MemCheckpointStreamFactory
implements CheckpointStorageLocation {
private final FileSystem fileSystem;
private final Path checkpointDirectory;
private final Path metadataFilePath;
/**
* Creates a checkpoint storage persists metadata to a file system and stores state
* in line in state handles with the metadata.
*
* @param fileSystem The file system to which the metadata will be written.
* @param checkpointDir The directory where the checkpoint metadata will be written.
*/
public PersistentMetadataCheckpointStorageLocation(
FileSystem fileSystem,
Path checkpointDir,
int maxStateSize) {
super(maxStateSize);
this.fileSystem = checkNotNull(fileSystem);
this.checkpointDirectory = checkNotNull(checkpointDir);
this.metadataFilePath = new Path(checkpointDir, AbstractFsCheckpointStorage.METADATA_FILE_NAME);
}
// ------------------------------------------------------------------------
@Override
public CheckpointMetadataOutputStream createMetadataOutputStream() throws IOException {
return new FsCheckpointMetadataOutputStream(fileSystem, metadataFilePath, checkpointDirectory);
}
@Override
public void disposeOnFailure() throws IOException {
// on a failure, no chunk in the checkpoint directory needs to be saved, so
// we can drop it as a whole
fileSystem.delete(checkpointDirectory, true);
}
@Override
public CheckpointStorageLocationReference getLocationReference() {
return CheckpointStorageLocationReference.getDefault();
}
}