com.unboundid.directory.sdk.ds.api

Class VirtualAttributeProvider

java.lang.Object

com.unboundid.directory.sdk.ds.api.VirtualAttributeProvider

All Implemented Interfaces:

Configurable, ExampleUsageProvider, Reconfigurable<VirtualAttributeProviderConfig>, UnboundIDExtension

@Extensible
 @DirectoryServerExtension
 @DirectoryProxyServerExtension(appliesToLocalContent=true,
                               appliesToRemoteContent=false)
 @SynchronizationServerExtension(appliesToLocalContent=true,
                                appliesToSynchronizedContent=false)
 @ThreadSafety(level=INTERFACE_THREADSAFE)
public abstract class VirtualAttributeProvider
extends java.lang.Object
implements UnboundIDExtension, Reconfigurable<VirtualAttributeProviderConfig>, ExampleUsageProvider

This class defines an API that must be implemented by extensions which construct attribute values which may be included in entries instead of or in addition to real values which are actually stored in the backend. The other attributes in the entry will be available for use in the process of generating the entry, and internal or external operations may also be performed if the generated values should incorporate data from other locations.

Each virtual attribute provider may be configured to indicate whether the associated virtual attribute should be included in a given entry. This criteria may include the entry's location in the DIT, whether it matches a given filter, whether it is a member of a specified group, and whether the requesting client has been assigned a given client connection policy. This is handled automatically by the server, so individual virtual attribute provider implementations do not need to attempt to perform that filtering on their own. However, they may perform additional processing if desired to further narrow the set of entries for which the virtual attribute should be generated.

In addition, virtual attribute providers may be configured to indicate the behavior that should be exhibited in the event that the target attribute already exists in the entry with one or more real values. In this case, the real values may be used instead of generating virtual values, the virtual values may be used in place of the real values, or both the real and virtual values may be merged and presented together. This work is also automatically performed by the server, so virtual attribute providers do not need to do any processing to determine whether to generate a value based on whether the target attribute already exists in the entry.

The server supports multiple virtual attribute providers targeting the same attribute applying to the same entry. Evaluation order and value selection is determined by the server based on configuration of the virtual attribute providers.

Configuring Virtual Attribute Providers

In order to configure a virtual attribute provider created using this API, use a command like:

      dsconfig create-virtual-attribute \
           --name "{name}" \
           --type third-party \
           --set enabled:true \
           --set attribute-type:{attribute} \
           --set "extension-class:{class-name}" \
           --set "extension-argument:{name=value}"
 

where "{name}" is the name to use for the virtual attribute provider instance, "{attribute}" is the name of the attribute for which the virtual attribute provider should be used to generate values, "{class-name}" is the fully-qualified name of the Java class that extends com.unboundid.directory.sdk.ds.api.VirtualAttributeProvider, and "{name=value}" represents name-value pairs for any arguments to provide to the virtual attribute provider. If multiple arguments should be provided to the virtual attribute provider, then the "--set extension-argument:{name=value}" option should be provided multiple times.

See Also:

ScriptedVirtualAttributeProvider

Constructor Summary

Constructors

Constructor and Description
VirtualAttributeProvider() Creates a new instance of this virtual attribute provider.

Method Summary

Modifier and Type	Method and Description
ResultCode	applyConfiguration(VirtualAttributeProviderConfig config, ArgumentParser parser, java.util.List<java.lang.String> adminActionsRequired, java.util.List<java.lang.String> messages) Attempts to apply the configuration from the provided argument parser to this extension.
void	defineConfigArguments(ArgumentParser parser) Updates the provided argument parser to define any configuration arguments which may be used by this extension.
void	finalizeVirtualAttributeProvider() Performs any cleanup which may be necessary when this virtual attribute provider is to be taken out of service.
abstract Attribute	generateAttribute(OperationContext operationContext, Entry entry, java.lang.String attributeName) Generates an attribute for inclusion in the provided entry.
java.util.Map<java.util.List<java.lang.String>,java.lang.String>	getExamplesArgumentSets() Retrieves a map containing examples of configurations that may be used for this extension.
abstract java.lang.String[]	getExtensionDescription() Retrieves a human-readable description for this extension.
abstract java.lang.String	getExtensionName() Retrieves a human-readable name for this extension.
void	initializeVirtualAttributeProvider(DirectoryServerContext serverContext, VirtualAttributeProviderConfig config, ArgumentParser parser) Initializes this virtual attribute provider.
boolean	isConfigurationAcceptable(VirtualAttributeProviderConfig config, ArgumentParser parser, java.util.List<java.lang.String> unacceptableReasons) Indicates whether the configuration represented by the provided argument parser is acceptable for use by this extension.
abstract boolean	isMultiValued() Indicates whether this virtual attribute provider may generate attributes with multiple values.
boolean	mayCacheInOperation() Indicates whether the server may cache values generated by this virtual attribute provider for reuse against the same entry in the course of processing the same operation.

Methods inherited from class java.lang.Object

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

Constructor Detail

VirtualAttributeProvider

public VirtualAttributeProvider()

Creates a new instance of this virtual attribute provider. All virtual attribute provider implementations must include a default constructor, but any initialization should generally be done in the initializeVirtualAttributeProvider method.

Method Detail

getExtensionName

public abstract java.lang.String getExtensionName()

Retrieves a human-readable name for this extension.

Specified by:

getExtensionName in interface UnboundIDExtension

Returns:

A human-readable name for this extension.

getExtensionDescription

public abstract java.lang.String[] getExtensionDescription()

Retrieves a human-readable description for this extension. Each element of the array that is returned will be considered a separate paragraph in generated documentation.

Specified by:

getExtensionDescription in interface UnboundIDExtension

Returns:

A human-readable description for this extension, or null or an empty array if no description should be available.

defineConfigArguments

public void defineConfigArguments(ArgumentParser parser)
                           throws ArgumentException

Updates the provided argument parser to define any configuration arguments which may be used by this extension. The argument parser may also be updated to define relationships between arguments (e.g., to specify required, exclusive, or dependent argument sets).

Specified by:

defineConfigArguments in interface Configurable

Parameters:

parser - The argument parser to be updated with the configuration arguments which may be used by this extension.

Throws:

ArgumentException - If a problem is encountered while updating the provided argument parser.

initializeVirtualAttributeProvider

public void initializeVirtualAttributeProvider(DirectoryServerContext serverContext,
                                               VirtualAttributeProviderConfig config,
                                               ArgumentParser parser)
                                        throws LDAPException

Initializes this virtual attribute provider.

Parameters:

serverContext - A handle to the server context for the server in which this extension is running.

config - The general configuration for this virtual attribute provider.

parser - The argument parser which has been initialized from the configuration for this virtual attribute provider.

Throws:

LDAPException - If a problem occurs while initializing this virtual attribute provider.

isConfigurationAcceptable

public boolean isConfigurationAcceptable(VirtualAttributeProviderConfig config,
                                         ArgumentParser parser,
                                         java.util.List<java.lang.String> unacceptableReasons)

Indicates whether the configuration represented by the provided argument parser is acceptable for use by this extension. The parser will have been used to parse any configuration available for this extension, and any automatic validation will have been performed. This method may be used to perform any more complex validation which cannot be performed automatically by the argument parser.

Specified by:

isConfigurationAcceptable in interface Reconfigurable<VirtualAttributeProviderConfig>

Parameters:

config - The general configuration for this extension.

parser - The argument parser that has been used to parse the proposed configuration for this extension.

unacceptableReasons - A list to which messages may be added to provide additional information about why the provided configuration is not acceptable.

Returns:

true if the configuration in the provided argument parser appears to be acceptable, or false if not.

applyConfiguration

public ResultCode applyConfiguration(VirtualAttributeProviderConfig config,
                                     ArgumentParser parser,
                                     java.util.List<java.lang.String> adminActionsRequired,
                                     java.util.List<java.lang.String> messages)

Attempts to apply the configuration from the provided argument parser to this extension.

Specified by:

applyConfiguration in interface Reconfigurable<VirtualAttributeProviderConfig>

Parameters:

config - The general configuration for this extension.

parser - The argument parser that has been used to parse the new configuration for this extension.

adminActionsRequired - A list to which messages may be added to provide additional information about any additional administrative actions that may be required to apply some of the configuration changes.

messages - A list to which messages may be added to provide additional information about the processing performed by this method.

Returns:

A result code providing information about the result of applying the configuration change. A result of SUCCESS should be used to indicate that all processing completed successfully. Any other result will indicate that a problem occurred during processing.

finalizeVirtualAttributeProvider

public void finalizeVirtualAttributeProvider()

Performs any cleanup which may be necessary when this virtual attribute provider is to be taken out of service.

mayCacheInOperation

public boolean mayCacheInOperation()

Indicates whether the server may cache values generated by this virtual attribute provider for reuse against the same entry in the course of processing the same operation.

Returns:

true if the server may cache the value generated by this virtual attribute provider for reuse with the same entry in the same operation, or false if not.

isMultiValued

public abstract boolean isMultiValued()

Indicates whether this virtual attribute provider may generate attributes with multiple values.

Returns:

true if this virtual attribute provider may generate attributes with multiple values, or false if it will only generate single-valued attributes.

generateAttribute

public abstract Attribute generateAttribute(OperationContext operationContext,
                                            Entry entry,
                                            java.lang.String attributeName)

Generates an attribute for inclusion in the provided entry.

Parameters:

operationContext - The operation context for the operation in progress, if any. It may be null if no operation is available.

entry - The entry for which the attribute is to be generated.

attributeName - The name of the attribute to be generated.

Returns:

The generated attribute, or null if no attribute should be generated.

getExamplesArgumentSets

public java.util.Map<java.util.List<java.lang.String>,java.lang.String> getExamplesArgumentSets()

Retrieves a map containing examples of configurations that may be used for this extension. The map key should be a list of sample arguments, and the corresponding value should be a description of the behavior that will be exhibited by the extension when used with that configuration.

Specified by:

getExamplesArgumentSets in interface ExampleUsageProvider

Returns:

A map containing examples of configurations that may be used for this extension. It may be null or empty if there should not be any example argument sets.