com.unboundid.directory.sdk.proxy.api

Class ProxiedExtendedOperationHandler

java.lang.Object

com.unboundid.directory.sdk.proxy.api.ProxiedExtendedOperationHandler

All Implemented Interfaces:

Configurable, ExampleUsageProvider, Reconfigurable<ProxiedExtendedOperationHandlerConfig>, UnboundIDExtension

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

This class defines an API that must be implemented by extensions which are used to forward extended operations to one or more backend servers. This API makes it possible to select the backend set(s) to which the operation should be forwarded, and to aggregate the responses into a single response to return to the client.

Configuring Proxied Extended Operation Handlers

In order to configure a proxied extended operation handler created using this API, use a command like:

      dsconfig create-extended-operation-handler \
           --handler-name "{handler-name}" \
           --type third-party-proxied \
           --set enabled:true \
           --set "extension-class:{class-name}" \
           --set "extension-argument:{name=value}"
 

where "{handler-name}" is the name to use for the proxied extended operation handler instance, "{class-name}" is the fully-qualified name of the Java class that extends com.unboundid.directory.sdk.proxy.api.ProxiedExtendedOperationHandler, and "{name=value}" represents name-value pairs for any arguments to provide to the proxied extended operation handler. If multiple arguments should be provided to the proxied extended operation handler, then the "--set extension-argument:{name=value}" option should be provided multiple times.

Constructor Summary

Constructors

Constructor and Description
ProxiedExtendedOperationHandler() Creates a new instance of this proxied extended operation handler.

Method Summary

Modifier and Type	Method and Description
ResultCode	applyConfiguration(ProxiedExtendedOperationHandlerConfig 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.
abstract ExtendedResult	createFinalResult(OperationContext operationContext, ExtendedRequest request, java.util.List<ExtendedResult> results) Creates the final extended result to return to the client from the provided list of results obtained from the set of entry-balanced and/or proxying request processors to which the request was forwarded.
void	defineConfigArguments(ArgumentParser parser) Updates the provided argument parser to define any configuration arguments which may be used by this extension.
void	finalizeProxiedExtendedOperationHandler() Performs any cleanup which may be necessary when this proxied extended operation handler is to be taken out of service.
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	getExtendedOperationName(java.lang.String oid) Retrieves the name of the extended operation with the provided OID.
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.
java.util.Set<java.lang.String>	getSupportedControls() Retrieves the OIDs of any controls supported by this proxied extended operation handler.
abstract java.util.Set<java.lang.String>	getSupportedExtensions() Retrieves the OIDs of the extended operation types supported by this proxied extended operation handler.
java.util.Set<java.lang.String>	getSupportedFeatures() Retrieves the OIDs of any features supported by this proxied extended operation handler that should be advertised in the server root DSE.
void	initializeProxiedExtendedOperationHandler(ProxyServerContext serverContext, ProxiedExtendedOperationHandlerConfig config, ArgumentParser parser) Initializes this proxied extended operation handler.
boolean	isConfigurationAcceptable(ProxiedExtendedOperationHandlerConfig 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 ExtendedResult	mergeEntryBalancedResults(OperationContext operationContext, ExtendedRequest request, EntryBalancingRequestProcessor requestProcessor, java.util.List<ObjectPair<ExtendedResult,BackendSet>> results, boolean fallbackAvailable) Obtains the extended result that should be used as a result of processing an operation in one or more entry-balanced backend sets, or throws an exception to indicate that the request should instead be forwarded to the fallback server set(s).
abstract ObjectPair<java.util.Set<BackendSet>,java.util.Set<BackendSet>>	selectBackendSets(OperationContext operationContext, ExtendedRequest request, EntryBalancingRequestProcessor requestProcessor) Selects the entry-balancing backend set(s) to which the provided extended request should be forwarded.
abstract boolean	shouldForward(OperationContext operationContext, ExtendedRequest request, ProxyingRequestProcessor requestProcessor) Indicates whether the provided extended request should be forwarded to one of the servers associated with the provided proxying request processor.

Methods inherited from class java.lang.Object

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

Constructor Detail

ProxiedExtendedOperationHandler

public ProxiedExtendedOperationHandler()

Creates a new instance of this proxied extended operation handler. All proxied extended operation handler implementations must include a default constructor, but any initialization should generally be done in the initializeProxiedExtendedOperationHandler 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.

initializeProxiedExtendedOperationHandler

public void initializeProxiedExtendedOperationHandler(ProxyServerContext serverContext,
                                                      ProxiedExtendedOperationHandlerConfig config,
                                                      ArgumentParser parser)
                                               throws LDAPException

Initializes this proxied extended operation handler.

Parameters:

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

config - The general configuration for this extended operation handler.

parser - The argument parser which has been initialized from the configuration for this extended operation handler.

Throws:

LDAPException - If a problem occurs while initializing this extended operation handler.

isConfigurationAcceptable

public boolean isConfigurationAcceptable(ProxiedExtendedOperationHandlerConfig 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<ProxiedExtendedOperationHandlerConfig>

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(ProxiedExtendedOperationHandlerConfig 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<ProxiedExtendedOperationHandlerConfig>

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.

finalizeProxiedExtendedOperationHandler

public void finalizeProxiedExtendedOperationHandler()

Performs any cleanup which may be necessary when this proxied extended operation handler is to be taken out of service.

getExtendedOperationName

public abstract java.lang.String getExtendedOperationName(java.lang.String oid)

Retrieves the name of the extended operation with the provided OID.

Parameters:

oid - The OID of the extended operation for which to retrieve the corresponding name.

Returns:

The name of the extended operation with the specified OID, or null if the specified OID is not recognized by this proxied extended operation handler.

getSupportedExtensions

public abstract java.util.Set<java.lang.String> getSupportedExtensions()

Retrieves the OIDs of the extended operation types supported by this proxied extended operation handler.

Returns:

The OIDs of the extended operation types supported by this proxied extended operation handler. It must not be null or empty, and the contents of the set returned must not change over the life of this proxied extended operation handler.

getSupportedControls

public java.util.Set<java.lang.String> getSupportedControls()

Retrieves the OIDs of any controls supported by this proxied extended operation handler.

Returns:

The OIDs of any controls supported by this proxied extended operation handler. It may be null or empty if this proxied extended operation handler does not support any controls.

getSupportedFeatures

public java.util.Set<java.lang.String> getSupportedFeatures()

Retrieves the OIDs of any features supported by this proxied extended operation handler that should be advertised in the server root DSE.

Returns:

The OIDs of any features supported by this proxied extended operation handler. It may be null or empty if this proxied extended operation handler does not support any features.

selectBackendSets

public abstract ObjectPair<java.util.Set<BackendSet>,java.util.Set<BackendSet>> selectBackendSets(OperationContext operationContext,
                                                                                                  ExtendedRequest request,
                                                                                                  EntryBalancingRequestProcessor requestProcessor)
                                                                                           throws LDAPException

Selects the entry-balancing backend set(s) to which the provided extended request should be forwarded. This method will only be invoked for operations in which the requester's client connection policy includes one or more subtree views which reference an entry-balancing request processor.

This method returns two groups of backend sets, with the first representing an initial guess (e.g., based on information obtained from the entry-balancing global index), and the second representing a fallback if the initial guess was found to be incorrect.

If it can be determined that no backend sets associated with the provided entry-balancing request processor should be used to process the extended operation, then the object returned may have both elements set to null or empty sets. If it is possible to definitively determine the set of backend sets to which the operation should be forwarded and no fallback option is required, then the first element of the returned object should be populated with a non-empty set and the second element should be null or empty.

Parameters:

operationContext - The operation context for the extended operation.

request - The extended request to be processed.

requestProcessor - The entry-balancing request processor in which the extended operation should be processed.

Returns:

The set of backend sets to which the request should be forwarded. It may be null (or it may be an ObjectPair with both elements empty or null) if the request should not be forwarded to any backend set for the entry-balancing request processor.

Throws:

LDAPException - If the request should not be forwarded to any of the backend sets for the provided entry-balancing request processor, and the result contained in the exception should be used instead.

mergeEntryBalancedResults

public abstract ExtendedResult mergeEntryBalancedResults(OperationContext operationContext,
                                                         ExtendedRequest request,
                                                         EntryBalancingRequestProcessor requestProcessor,
                                                         java.util.List<ObjectPair<ExtendedResult,BackendSet>> results,
                                                         boolean fallbackAvailable)
                                                  throws LDAPException

Obtains the extended result that should be used as a result of processing an operation in one or more entry-balanced backend sets, or throws an exception to indicate that the request should instead be forwarded to the fallback server set(s).

This method will only be invoked for cases in which the selectBackendSets(com.unboundid.directory.sdk.common.types.OperationContext, com.unboundid.directory.sdk.common.operation.ExtendedRequest, com.unboundid.directory.sdk.proxy.types.EntryBalancingRequestProcessor) method indicates that multiple backend sets should be accessed in the course of processing an extended request.

Parameters:

operationContext - The operation context for the extended operation.

request - The extended request that was processed.

requestProcessor - The entry-balancing request processor in which the extended operation was processed.

results - A list of the extended results obtained from processing the operation in the selected set of backend sets, with each result paired with information about the backend set from which it was obtained.

fallbackAvailable - Indicates whether a fallback group of backend sets is available and may be used as a second attempt at processing the operation if the result from the initial attempt is not acceptable.

Returns:

An extended result that represents the merged result from the provided list of results. It must not be null.

Throws:

LDAPException - To indicate that the initial set of results was not acceptable and that the operation should instead be forwarded to the fallback group of backend sets. If no fallback set of results is available, then an extended result will be generated from the content of this exception.

shouldForward

public abstract boolean shouldForward(OperationContext operationContext,
                                      ExtendedRequest request,
                                      ProxyingRequestProcessor requestProcessor)
                               throws LDAPException

Indicates whether the provided extended request should be forwarded to one of the servers associated with the provided proxying request processor. Note that this method will not be invoked for proxying request processors associated with an entry-balancing request processor.

Parameters:

operationContext - The operation context for the extended operation.

request - The extended request to be processed.

requestProcessor - The proxying request processor for which to make the determination.

Returns:

true if the extended request should be forwarded to one of the servers associated with the proxying request processor, or false if not.

Throws:

LDAPException - If the request should not be forwarded to a backend server associated with the proxying request processor, but the result contained in the exception should be used instead.

createFinalResult

public abstract ExtendedResult createFinalResult(OperationContext operationContext,
                                                 ExtendedRequest request,
                                                 java.util.List<ExtendedResult> results)

Creates the final extended result to return to the client from the provided list of results obtained from the set of entry-balanced and/or proxying request processors to which the request was forwarded.

Parameters:

operationContext - The operation context for the extended operation.

request - The extended request that was processed.

results - The results from all request processors to which the request was forwarded. It may be empty if the request was not forwarded to any backend servers, in which case this method must construct an appropriate result. It may have only a single element if the request was only forwarded to one server, and in many cases it may be desirable to simply use that result as the final result. It may also have multiple elements if the request was forwarded to multiple backend servers, in which case this method must determine whether to return one of them to the client, or to construct a new result to return instead.

Returns:

The final extended result to be returned to the client.

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.