Package org.apache.hadoop.fs.azurebfs.commit

Interface ResilientCommitByRename

All Superinterfaces:

org.apache.hadoop.fs.statistics.IOStatisticsSource

All Known Implementing Classes:

AzureBlobFileSystem.ResilientCommitByRenameImpl

@Private
@Unstable
public interface ResilientCommitByRename
extends org.apache.hadoop.fs.statistics.IOStatisticsSource

API exclusively for committing files. This is only for use by (@link AbfsManifestStoreOperations, and is intended to be implemented by ABFS. To ensure that there is no need to add mapreduce JARs to the classpath just to work with ABFS, this interface MUST NOT refer to anything in the org.apache.hadoop.mapreduce package.

Method Summary

Modifier and Type	Method	Description
org.apache.commons.lang3.tuple.Pair<java.lang.Boolean,java.time.Duration>	commitSingleFileByRename(org.apache.hadoop.fs.Path source, org.apache.hadoop.fs.Path dest, java.lang.String sourceEtag)	Rename source file to dest path *Exactly*; no subdirectory games here.

Methods inherited from interface org.apache.hadoop.fs.statistics.IOStatisticsSource

getIOStatistics

Method Detail

commitSingleFileByRename

org.apache.commons.lang3.tuple.Pair<java.lang.Boolean,java.time.Duration> commitSingleFileByRename(org.apache.hadoop.fs.Path source,
                                                                                                         org.apache.hadoop.fs.Path dest,
                                                                                                         @Nullable
                                                                                                         java.lang.String sourceEtag)
                                                                                                  throws java.io.IOException

Rename source file to dest path *Exactly*; no subdirectory games here. if the method does not raise an exception,then the data at dest is the data which was at source. Requirements

   exists(FS, source) else raise FileNotFoundException
   source != dest else raise PathIOException
   not exists(FS, dest)
   isDir(FS, dest.getParent)
 

1. source != dest else raise PathIOException
2. source must exist else raise FileNotFoundException
3. source must exist and be a file
4. dest must not exist;
5. dest.getParent() must be a dir
6. if sourceEtag is non-empty, it MAY be used to qualify/validate the rename.

The outcome of the operation is undefined if source is not a file, dest exists, dest.getParent() doesn't exist/is a file. That is: implementations SHOULD assume that the code calling this method has set up the destination directory tree and is only invoking this call on a file. Accordingly: implementations MAY skip validation checks Post Conditions on a successful operation:

 FS' where:
     not exists(FS', source)
     and exists(FS', dest)
     and data(FS', dest) == data (FS, source)
 

This is exactly the same outcome as `FileSystem.rename()` when the same preconditions are met. This API call simply restricts the operation to file rename with strict conditions, (no need to be 'clever' about dest path calculation) and the ability to pass in etags, modtimes and file status values.

Parameters:

source - path to source file

dest - destination of rename.

sourceEtag - etag of source file. may be null or empty

Returns:

true if recovery was needed.

Throws:

java.io.FileNotFoundException - source file not found

org.apache.hadoop.fs.PathIOException - failure, including source and dest being the same path

java.io.IOException - any other exception