gov.loc.repository.bagit.verify

Class BagVerifier

java.lang.Object

gov.loc.repository.bagit.verify.BagVerifier

All Implemented Interfaces:

java.lang.AutoCloseable

public final class BagVerifier
extends java.lang.Object
implements java.lang.AutoCloseable

Responsible for verifying if a bag is valid, complete

Constructor Summary

Constructors

Constructor and Description
BagVerifier() Create a BagVerifier with a cached thread pool and a StandardBagitAlgorithmNameToSupportedAlgorithmMapping
BagVerifier(BagitAlgorithmNameToSupportedAlgorithmMapping nameMapping) Create a BagVerifier with a cached thread pool and a custom mapping
BagVerifier(java.util.concurrent.ExecutorService executor) Create a BagVerifier with a custom thread pool and a StandardBagitAlgorithmNameToSupportedAlgorithmMapping
BagVerifier(java.util.concurrent.ExecutorService executor, BagitAlgorithmNameToSupportedAlgorithmMapping nameMapping) Create a BagVerifier with a custom thread pool and a custom mapping

Method Summary

Modifier and Type	Method and Description
static boolean	canQuickVerify(Bag bag) Determine if we can quickly verify by comparing the number of files and the total number of bytes expected
void	close()
java.util.concurrent.ExecutorService	getExecutor()
ManifestVerifier	getManifestVerifier()
void	isComplete(Bag bag, boolean ignoreHiddenFiles) See https://tools.ietf.org/html/draft-kunze-bagit-13#section-3 A bag is complete if every element is present every file in the payload manifest(s) are present every file in the tag manifest(s) are present.
void	isValid(Bag bag, boolean ignoreHiddenFiles) See https://tools.ietf.org/html/draft-kunze-bagit-13#section-3 A bag is valid if the bag is complete and every checksum has been verified against the contents of its corresponding file.
static void	quicklyVerify(Bag bag) Quickly verify by comparing the number of files and the total number of bytes expected

Methods inherited from class java.lang.Object

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

Constructor Detail

BagVerifier

public BagVerifier()

Create a BagVerifier with a cached thread pool and a StandardBagitAlgorithmNameToSupportedAlgorithmMapping

BagVerifier

public BagVerifier(BagitAlgorithmNameToSupportedAlgorithmMapping nameMapping)

Create a BagVerifier with a cached thread pool and a custom mapping

Parameters:

nameMapping - the mapping between BagIt algorithm name and the java supported algorithm

BagVerifier

public BagVerifier(java.util.concurrent.ExecutorService executor)

Create a BagVerifier with a custom thread pool and a StandardBagitAlgorithmNameToSupportedAlgorithmMapping

Parameters:

executor - the thread pool to use when doing work

BagVerifier

public BagVerifier(java.util.concurrent.ExecutorService executor,
                   BagitAlgorithmNameToSupportedAlgorithmMapping nameMapping)

Create a BagVerifier with a custom thread pool and a custom mapping

Parameters:

nameMapping - the mapping between BagIt algorithm name and the java supported algorithm

executor - the thread pool to use when doing work

Method Detail

close

public void close()
           throws java.lang.SecurityException

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.lang.SecurityException

canQuickVerify

public static boolean canQuickVerify(Bag bag)

Determine if we can quickly verify by comparing the number of files and the total number of bytes expected

Parameters:

bag - the Bag object you wish to check

Returns:

true if the bag can be quickly verified

quicklyVerify

public static void quicklyVerify(Bag bag)
                          throws java.io.IOException,
                                 InvalidPayloadOxumException

Quickly verify by comparing the number of files and the total number of bytes expected

Parameters:

bag - the bag to verify by payload-oxum

Throws:

java.io.IOException - if there is an error reading a file

InvalidPayloadOxumException - if either the total bytes or the number of files calculated for the payload directory of the bag is different than the supplied values

PayloadOxumDoesNotExistException - if the bag does not contain a payload-oxum. To check, run canQuickVerify(gov.loc.repository.bagit.domain.Bag)

isValid

public void isValid(Bag bag,
                    boolean ignoreHiddenFiles)
             throws java.io.IOException,
                    FileNotInManifestException,
                    MissingPayloadManifestException,
                    MissingBagitFileException,
                    MissingPayloadDirectoryException,
                    FileNotInPayloadDirectoryException,
                    java.lang.InterruptedException,
                    MaliciousPathException,
                    CorruptChecksumException,
                    VerificationException,
                    UnsupportedAlgorithmException,
                    InvalidBagitFileFormatException

See https://tools.ietf.org/html/draft-kunze-bagit-13#section-3
A bag is valid if the bag is complete and every checksum has been verified against the contents of its corresponding file.

Parameters:

bag - the Bag object to check

ignoreHiddenFiles - ignore hidden files unless explicitly listed in manifest(s)

Throws:

CorruptChecksumException - when the computed hash doesn't match given hash

java.io.IOException - if there was an error with the file

FileNotInManifestException - if a file is found in the payload directory but not in manifest(s)

MissingPayloadManifestException - if there is not at least one payload manifest

MissingBagitFileException - if there is no bagit.txt file

MissingPayloadDirectoryException - if there is no /data directory

FileNotInPayloadDirectoryException - if a manifest lists a file but it is not in the payload directory

java.lang.InterruptedException - if the threads are interrupted when checking if all files are listed in manifest(s)

MaliciousPathException - if there is path that is referenced in the manifest that is outside the bag root directory

VerificationException - some other exception happened during processing so capture it here.

UnsupportedAlgorithmException - if the manifest uses a algorithm that isn't supported

InvalidBagitFileFormatException - if the manifest is not formatted properly

isComplete

public void isComplete(Bag bag,
                       boolean ignoreHiddenFiles)
                throws java.io.IOException,
                       MissingPayloadManifestException,
                       MissingBagitFileException,
                       MissingPayloadDirectoryException,
                       FileNotInPayloadDirectoryException,
                       java.lang.InterruptedException,
                       MaliciousPathException,
                       UnsupportedAlgorithmException,
                       InvalidBagitFileFormatException

See https://tools.ietf.org/html/draft-kunze-bagit-13#section-3
A bag is complete if

• every element is present
• every file in the payload manifest(s) are present
• every file in the tag manifest(s) are present. Tag files not listed in a tag manifest may be present.
• every file in the data directory must be listed in at least one payload manifest
• each element must comply with the bagit spec

Parameters:

bag - the Bag object to check

ignoreHiddenFiles - ignore hidden files unless explicitly listed in manifest(s)

Throws:

java.io.IOException - if there was an error with the file

MissingPayloadManifestException - if there is not at least one payload manifest

MissingBagitFileException - if there is no bagit.txt file

MissingPayloadDirectoryException - if there is no /data directory

FileNotInPayloadDirectoryException - if a manifest lists a file but it is not in the payload directory

java.lang.InterruptedException - if the threads are interrupted when checking if all files are listed in manifest(s)

MaliciousPathException - if there is path that is referenced in the manifest that is outside the bag root directory

UnsupportedAlgorithmException - if the manifest uses a algorithm that isn't supported

InvalidBagitFileFormatException - if the manifest is not formatted properly

getExecutor

public java.util.concurrent.ExecutorService getExecutor()

getManifestVerifier

public ManifestVerifier getManifestVerifier()