org.dspace.storage.bitstore

Class S3BitStoreService

java.lang.Object

org.dspace.storage.bitstore.S3BitStoreService

All Implemented Interfaces:

BitStoreService

public class S3BitStoreService
extends Object
implements BitStoreService

Asset store using Amazon's Simple Storage Service (S3). S3 is a commercial, web-service accessible, remote storage facility. NB: you must have obtained an account with Amazon to use this store

Author:

Richard Rodgers, Peter Dietz

Constructor Summary

Constructors

Constructor and Description
S3BitStoreService()

Method Summary

Modifier and Type	Method and Description
Map	about(Bitstream bitstream, Map attrs) Obtain technical metadata about an asset in the asset store.
String	generateId() Return an identifier unique to this asset store instance
InputStream	get(Bitstream bitstream) Retrieve the bits for the asset with ID.
String	getAwsAccessKey()
String	getAwsRegionName()
String	getAwsSecretKey()
String	getBucketName()
String	getFullKey(String id) Utility Method: Prefix the key with a subfolder, if this instance assets are stored within subfolder
String	getSubfolder()
void	init() Initialize the asset store S3 Requires: - access key - secret key - bucket name
static void	main(String[] args) Contains a command-line testing tool.
void	put(Bitstream bitstream, InputStream in) Store a stream of bits.
void	remove(Bitstream bitstream) Remove an asset from the asset store.
void	setAwsAccessKey(String awsAccessKey)
void	setAwsRegionName(String awsRegionName)
void	setAwsSecretKey(String awsSecretKey)
void	setBucketName(String bucketName)
void	setSubfolder(String subfolder)

Methods inherited from class java.lang.Object

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

Constructor Detail

S3BitStoreService

public S3BitStoreService()

Method Detail

init

public void init()
          throws IOException

Initialize the asset store S3 Requires: - access key - secret key - bucket name

Specified by:

init in interface BitStoreService

Throws:

IOException

generateId

public String generateId()

Return an identifier unique to this asset store instance

Specified by:

generateId in interface BitStoreService

Returns:

a unique ID

get

public InputStream get(Bitstream bitstream)
                throws IOException

Retrieve the bits for the asset with ID. If the asset does not exist, returns null.

Specified by:

get in interface BitStoreService

Parameters:

bitstream - The ID of the asset to retrieve

Returns:

The stream of bits, or null

Throws:

IOException - If a problem occurs while retrieving the bits

put

public void put(Bitstream bitstream,
                InputStream in)
         throws IOException

Store a stream of bits.

If this method returns successfully, the bits have been stored. If an exception is thrown, the bits have not been stored.

Specified by:

put in interface BitStoreService

Parameters:

in - The stream of bits to store

bitstream - The bitstream object

Throws:

IOException - If a problem occurs while storing the bits

about

public Map about(Bitstream bitstream,
                 Map attrs)
          throws IOException

Obtain technical metadata about an asset in the asset store. Checksum used is (ETag) hex encoded 128-bit MD5 digest of an object's content as calculated by Amazon S3 (Does not use getContentMD5, as that is 128-bit MD5 digest calculated on caller's side)

Specified by:

about in interface BitStoreService

Parameters:

bitstream - The asset to describe

attrs - A Map whose keys consist of desired metadata fields

Returns:

attrs A Map with key/value pairs of desired metadata If file not found, then return null

Throws:

IOException - If a problem occurs while obtaining metadata

remove

public void remove(Bitstream bitstream)
            throws IOException

Remove an asset from the asset store. An irreversible operation.

Specified by:

remove in interface BitStoreService

Parameters:

bitstream - The asset to delete

Throws:

IOException - If a problem occurs while removing the asset

getFullKey

public String getFullKey(String id)

Utility Method: Prefix the key with a subfolder, if this instance assets are stored within subfolder

Parameters:

id -

Returns:

full key prefixed with a subfolder, if applicable

getAwsAccessKey

public String getAwsAccessKey()

setAwsAccessKey

public void setAwsAccessKey(String awsAccessKey)

getAwsSecretKey

public String getAwsSecretKey()

setAwsSecretKey

public void setAwsSecretKey(String awsSecretKey)

getAwsRegionName

public String getAwsRegionName()

setAwsRegionName

public void setAwsRegionName(String awsRegionName)

getBucketName

public String getBucketName()

setBucketName

public void setBucketName(String bucketName)

getSubfolder

public String getSubfolder()

setSubfolder

public void setSubfolder(String subfolder)

main

public static void main(String[] args)
                 throws Exception

Contains a command-line testing tool. Expects arguments: -a accessKey -s secretKey -f assetFileName

Parameters:

args - Command line arguments

Throws:

Exception