org.apache.hadoop.fs.s3native
Class NativeS3FileSystem

java.lang.Object
  org.apache.hadoop.conf.Configured
      org.apache.hadoop.fs.FileSystem
          org.apache.hadoop.fs.s3native.NativeS3FileSystem

All Implemented Interfaces:

Closeable, Configurable

@InterfaceAudience.Public
@InterfaceStability.Stable
public class NativeS3FileSystem
extends FileSystem

A FileSystem for reading and writing files stored on Amazon S3. Unlike S3FileSystem this implementation stores files on S3 in their native form so they can be read by other S3 tools. A note about directories. S3 of course has no "native" support for them. The idiom we choose then is: for any directory created by this class, we use an empty object "#{dirpath}_$folder$" as a marker. Further, to interoperate with other S3 tools, we also accept the following: - an object "#{dirpath}/' denoting a directory marker - if there exists any objects with the prefix "#{dirpath}/", then the directory is said to exist - if both a file with the name of a directory and a marker for that directory exists, then the *file masks the directory*, and the directory is never returned.

See Also:

S3FileSystem

Field Summary

static org.apache.commons.logging.Log

LOG

Fields inherited from class org.apache.hadoop.fs.FileSystem

DEFAULT_FS, FS_DEFAULT_NAME_KEY, SHUTDOWN_HOOK_PRIORITY, statistics

Constructor Summary

NativeS3FileSystem()

NativeS3FileSystem(org.apache.hadoop.fs.s3native.NativeFileSystemStore store)

Method Summary

FSDataOutputStream	append(Path f, int bufferSize, Progressable progress) This optional operation is not yet supported.
FSDataOutputStream	create(Path f, FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress) Create an FSDataOutputStream at the indicated Path with write-progress reporting.
boolean	delete(Path f, boolean recurse) Delete a file.
String	getCanonicalServiceName() Get a canonical service name for this file system.
long	getDefaultBlockSize() Return the number of bytes that large input files should be optimally be split into to minimize i/o time.
FileStatus	getFileStatus(Path f) Return a file status object that represents the path.
String	getScheme() Return the protocol scheme for the FileSystem.
URI	getUri() Returns a URI whose scheme and authority identify this FileSystem.
Path	getWorkingDirectory() Get the current working directory for the given file system
void	initialize(URI uri, Configuration conf) Called after a new FileSystem instance is constructed.
FileStatus[]	listStatus(Path f) If f is a file, this method will make a single call to S3.
boolean	mkdirs(Path f, FsPermission permission) Make the given file and all non-existent parents into directories.
FSDataInputStream	open(Path f, int bufferSize) Opens an FSDataInputStream at the indicated Path.
boolean	rename(Path src, Path dst) Renames Path src to Path dst.
void	setWorkingDirectory(Path newDir) Set the working directory to the given directory.

Methods inherited from class org.apache.hadoop.fs.FileSystem

append, append, areSymlinksEnabled, cancelDeleteOnExit, canonicalizeUri, checkPath, clearStatistics, close, closeAll, closeAllForUGI, completeLocalOutput, concat, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyToLocalFile, copyToLocalFile, copyToLocalFile, create, create, create, create, create, create, create, create, create, create, create, create, createNewFile, createNonRecursive, createNonRecursive, createNonRecursive, createSnapshot, createSnapshot, createSymlink, delete, deleteOnExit, deleteSnapshot, enableSymlinks, exists, fixRelativePart, get, get, get, getAclStatus, getAllStatistics, getBlockSize, getCanonicalUri, getContentSummary, getDefaultBlockSize, getDefaultPort, getDefaultReplication, getDefaultReplication, getDefaultUri, getFileBlockLocations, getFileBlockLocations, getFileChecksum, getFileLinkStatus, getFileSystemClass, getFSofPath, getHomeDirectory, getInitialWorkingDirectory, getLength, getLinkTarget, getLocal, getName, getNamed, getReplication, getServerDefaults, getServerDefaults, getStatistics, getStatistics, getStatus, getStatus, getUsed, globStatus, globStatus, isDirectory, isFile, listCorruptFileBlocks, listFiles, listLocatedStatus, listLocatedStatus, listStatus, listStatus, listStatus, makeQualified, mkdirs, mkdirs, modifyAclEntries, moveFromLocalFile, moveFromLocalFile, moveToLocalFile, newInstance, newInstance, newInstance, newInstanceLocal, open, primitiveCreate, primitiveMkdir, primitiveMkdir, printStatistics, processDeleteOnExit, removeAcl, removeAclEntries, removeDefaultAcl, rename, renameSnapshot, resolveLink, resolvePath, setAcl, setDefaultUri, setDefaultUri, setOwner, setPermission, setReplication, setTimes, setVerifyChecksum, setWriteChecksum, startLocalOutput, supportsSymlinks

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

public static final org.apache.commons.logging.Log LOG

Constructor Detail

NativeS3FileSystem

public NativeS3FileSystem()

NativeS3FileSystem

public NativeS3FileSystem(org.apache.hadoop.fs.s3native.NativeFileSystemStore store)

Method Detail

getScheme

public String getScheme()

Return the protocol scheme for the FileSystem.

Overrides:

getScheme in class FileSystem

Returns:

s3n

initialize

public void initialize(URI uri,
                       Configuration conf)
                throws IOException

Description copied from class: FileSystem

Called after a new FileSystem instance is constructed.

Overrides:

initialize in class FileSystem

Parameters:

uri - a uri whose authority section names the host, port, etc. for this FileSystem

conf - the configuration

Throws:

IOException

append

public FSDataOutputStream append(Path f,
                                 int bufferSize,
                                 Progressable progress)
                          throws IOException

This optional operation is not yet supported.

Specified by:

append in class FileSystem

Parameters:

f - the existing file to be appended.

bufferSize - the size of the buffer to be used.

progress - for reporting progress if it is not null.

Throws:

IOException

create

public FSDataOutputStream create(Path f,
                                 FsPermission permission,
                                 boolean overwrite,
                                 int bufferSize,
                                 short replication,
                                 long blockSize,
                                 Progressable progress)
                          throws IOException

Description copied from class: FileSystem

Create an FSDataOutputStream at the indicated Path with write-progress reporting.

Specified by:

create in class FileSystem

Parameters:

f - the file name to open

overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.

bufferSize - the size of the buffer to be used.

replication - required block replication for the file.

Throws:

IOException

See Also:

FileSystem.setPermission(Path, FsPermission)

delete

public boolean delete(Path f,
                      boolean recurse)
               throws IOException

Description copied from class: FileSystem

Delete a file.

Specified by:

delete in class FileSystem

Parameters:

f - the path to delete.

recurse - if path is a directory and set to true, the directory is deleted else throws an exception. In case of a file the recursive can be set to either true or false.

Returns:

true if delete is successful else false.

Throws:

IOException

getFileStatus

public FileStatus getFileStatus(Path f)
                         throws IOException

Description copied from class: FileSystem

Return a file status object that represents the path.

Specified by:

getFileStatus in class FileSystem

Parameters:

f - The path we want information from

Returns:

a FileStatus object

Throws:

FileNotFoundException - when the path does not exist; IOException see specific implementation

IOException

getUri

public URI getUri()

Description copied from class: FileSystem

Returns a URI whose scheme and authority identify this FileSystem.

Specified by:

getUri in class FileSystem

listStatus

public FileStatus[] listStatus(Path f)
                        throws IOException

If f is a file, this method will make a single call to S3. If f is a directory, this method will make a maximum of (n / 1000) + 2 calls to S3, where n is the total number of files and directories contained directly in f.

Specified by:

listStatus in class FileSystem

Parameters:

f - given path

Returns:

the statuses of the files/directories in the given patch

Throws:

FileNotFoundException - when the path does not exist; IOException see specific implementation

IOException

mkdirs

public boolean mkdirs(Path f,
                      FsPermission permission)
               throws IOException

Description copied from class: FileSystem

Make the given file and all non-existent parents into directories. Has the semantics of Unix 'mkdir -p'. Existence of the directory hierarchy is not an error.

Specified by:

mkdirs in class FileSystem

Parameters:

f - path to create

permission - to apply to f

Throws:

IOException

open

public FSDataInputStream open(Path f,
                              int bufferSize)
                       throws IOException

Description copied from class: FileSystem

Opens an FSDataInputStream at the indicated Path.

Specified by:

open in class FileSystem

Parameters:

f - the file name to open

bufferSize - the size of the buffer to be used.

Throws:

IOException

rename

public boolean rename(Path src,
                      Path dst)
               throws IOException

Description copied from class: FileSystem

Renames Path src to Path dst. Can take place on local fs or remote DFS.

Specified by:

rename in class FileSystem

Parameters:

src - path to be renamed

dst - new path after rename

Returns:

true if rename is successful

Throws:

IOException - on failure

getDefaultBlockSize

public long getDefaultBlockSize()

Description copied from class: FileSystem

Return the number of bytes that large input files should be optimally be split into to minimize i/o time.

Overrides:

getDefaultBlockSize in class FileSystem

setWorkingDirectory

public void setWorkingDirectory(Path newDir)

Set the working directory to the given directory.

Specified by:

setWorkingDirectory in class FileSystem

getWorkingDirectory

public Path getWorkingDirectory()

Description copied from class: FileSystem

Get the current working directory for the given file system

Specified by:

getWorkingDirectory in class FileSystem

Returns:

the directory pathname

getCanonicalServiceName

public String getCanonicalServiceName()

Description copied from class: FileSystem

Get a canonical service name for this file system. The token cache is the only user of the canonical service name, and uses it to lookup this filesystem's service tokens. If file system provides a token of its own then it must have a canonical name, otherwise canonical name can be null. Default Impl: If the file system has child file systems (such as an embedded file system) then it is assumed that the fs has no tokens of its own and hence returns a null name; otherwise a service name is built using Uri and port.

Returns:

a service string that uniquely identifies this file system, null if the filesystem does not implement tokens

See Also:

SecurityUtil.buildDTServiceName(URI, int)