org.apache.hadoop.security.alias

Class CredentialProvider

java.lang.Object

org.apache.hadoop.security.alias.CredentialProvider

@InterfaceAudience.Public
 @InterfaceStability.Unstable
public abstract class CredentialProvider
extends Object

A provider of credentials or password for Hadoop applications. Provides an abstraction to separate credential storage from users of them. It is intended to support getting or storing passwords in a variety of ways, including third party bindings. CredentialProvider implementations must be thread safe.

Field Summary

Fields

Modifier and Type	Field and Description
static String	CLEAR_TEXT_FALLBACK

Constructor Summary

Constructors

Constructor and Description
CredentialProvider()

Method Summary

Modifier and Type	Method and Description
abstract org.apache.hadoop.security.alias.CredentialProvider.CredentialEntry	createCredentialEntry(String name, char[] credential) Create a new credential.
abstract void	deleteCredentialEntry(String name) Delete the given credential.
abstract void	flush() Ensures that any changes to the credentials are written to persistent store.
abstract List<String>	getAliases() Get the aliases for all credentials.
abstract org.apache.hadoop.security.alias.CredentialProvider.CredentialEntry	getCredentialEntry(String alias) Get the credential entry for a specific alias.
boolean	isTransient() Indicates whether this provider represents a store that is intended for transient use - such as the UserProvider is.
boolean	needsPassword() Does this provider require a password? This means that a password is required for normal operation, and it has not been found through normal means.
String	noPasswordError() If a password for the provider is needed, but is not provided, this will return an error message and instructions for supplying said password to the provider.
String	noPasswordWarning() If a password for the provider is needed, but is not provided, this will return a warning and instructions for supplying said password to the provider.

Methods inherited from class java.lang.Object

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

Field Detail

CLEAR_TEXT_FALLBACK

public static final String CLEAR_TEXT_FALLBACK

See Also:

Constant Field Values

Constructor Detail

CredentialProvider

public CredentialProvider()

Method Detail

isTransient

public boolean isTransient()

Indicates whether this provider represents a store that is intended for transient use - such as the UserProvider is. These providers are generally used to provide job access to passwords rather than for long term storage.

Returns:

true if transient, false otherwise

flush

public abstract void flush()
                    throws IOException

Ensures that any changes to the credentials are written to persistent store.

Throws:

IOException - raised on errors performing I/O.

getCredentialEntry

public abstract org.apache.hadoop.security.alias.CredentialProvider.CredentialEntry getCredentialEntry(String alias)
                                                                                                throws IOException

Get the credential entry for a specific alias.

Parameters:

alias - the name of a specific credential

Returns:

the credentialEntry

Throws:

IOException - raised on errors performing I/O.

getAliases

public abstract List<String> getAliases()
                                 throws IOException

Get the aliases for all credentials.

Returns:

the list of alias names

Throws:

IOException - raised on errors performing I/O.

createCredentialEntry

public abstract org.apache.hadoop.security.alias.CredentialProvider.CredentialEntry createCredentialEntry(String name,
                                                                                                          char[] credential)
                                                                                                   throws IOException

Create a new credential. The given alias must not already exist.

Parameters:

name - the alias of the credential

credential - the credential value for the alias.

Returns:

CredentialEntry.

Throws:

IOException - raised on errors performing I/O.

deleteCredentialEntry

public abstract void deleteCredentialEntry(String name)
                                    throws IOException

Delete the given credential.

Parameters:

name - the alias of the credential to delete

Throws:

IOException - raised on errors performing I/O.

needsPassword

public boolean needsPassword()
                      throws IOException

Does this provider require a password? This means that a password is required for normal operation, and it has not been found through normal means. If true, the password should be provided by the caller using setPassword().

Returns:

Whether or not the provider requires a password

Throws:

IOException - raised on errors performing I/O.

noPasswordWarning

public String noPasswordWarning()

If a password for the provider is needed, but is not provided, this will return a warning and instructions for supplying said password to the provider.

Returns:

A warning and instructions for supplying the password

noPasswordError

public String noPasswordError()

If a password for the provider is needed, but is not provided, this will return an error message and instructions for supplying said password to the provider.

Returns:

An error message and instructions for supplying the password