XrdSsiService Class Reference

#include <XrdSsiService.hh>

Inheritance diagram for XrdSsiService:

Public Member Functions
int	GetVersion ()
virtual bool	Attach (XrdSsiErrInfo &eInfo, const std::string &handle, XrdSsiRequest &reqRef, XrdSsiResource *resP=0)
	Attach to a backgrounded request.
virtual bool	Prepare (XrdSsiErrInfo &eInfo, const XrdSsiResource &rDesc)
	Prepare for processing subsequent resource request.
virtual void	ProcessRequest (XrdSsiRequest &reqRef, XrdSsiResource &resRef)=0
	Process a request; client-side or server-side.
virtual bool	Stop (bool immed=false)
	Stop the client-side service. This is never called server-side.
	XrdSsiService ()
	Constructor.

Static Public Attributes
static const int	SsiVersion = 0x00020000

Protected Member Functions
virtual	~XrdSsiService ()
	Destructor. The service object cannot be explicitly deleted. Use Stop().

Constructor & Destructor Documentation

XrdSsiService()

XrdSsiService::XrdSsiService ( )

inline

Constructor.

~XrdSsiService()

virtual XrdSsiService::~XrdSsiService ( )

inlineprotectedvirtual

Destructor. The service object cannot be explicitly deleted. Use Stop().

Member Function Documentation

Attach()

virtual bool XrdSsiService::Attach ( XrdSsiErrInfo &  eInfo, const std::string &  handle, XrdSsiRequest &  reqRef, XrdSsiResource *  resP = 0  )

inlinevirtual

Attach to a backgrounded request.

When a client calls Attach() the server-side Attach() is invoked to indicate that the backgrounded request is now a foreground request. Many times such notification is not needed so a default nil implementation is provided. Server-side Attach() calls are always passed the original request object reference so that it can pair up the request with the attach.

Parameters

eInfo	Reference to an error info object which will contain the error describing why the attach failed (i.e. return false).
handle	Reference to the handle provided to the callback method XrdSsiRequest::ProcessResponse() via isHandle response type. This is always an empty string on server-side calls.
reqRef	Reference to the request object that is to attach to the backgrounded request. It need not be the original request object (client-side) but it always is the original request object server-side.
resP	A pointer to the resource object describing the request resources. This is meaningless for client calls and should not be specified. For server-side calls, it can be used to reauthorize the request since the client performing the attach may be different from the client that actually started the request.

Returns

true Continue normally, no issues detected. false An exception occurred, the eInfo object has the reason. For server side calls this provides the service the ability to reject request reattachment.

GetVersion()

int XrdSsiService::GetVersion ( )

inline

References SsiVersion.

Prepare()

virtual bool XrdSsiService::Prepare ( XrdSsiErrInfo &  eInfo, const XrdSsiResource &  rDesc  )

virtual

Prepare for processing subsequent resource request.

This method is meant to be used server-side to optimize subsequent request processing, perform authorization, and allow a service to stall or redirect requests. It is optional and a default implementation is provided that simply asks the provider if the resource exists on the server. Clients need not call or implement this method.

Parameters

eInfo	The object where error information is to be placed.
rDesc	Reference to the resource object that describes the resource subsequent requests will use.

Returns

true Continue normally, no issues detected. false An exception occurred, the eInfo object has the reason.

Special notes for server-side processing:

1) Two special errors are recognized that allow for a client retry:

resP->eInfo.eNum = EAGAIN (client should retry elsewhere) resP->eInfo.eMsg = the host name where the client is redirected resP->eInfo.eArg = the port number to be used by the client

resP->eInfo.eNum = EBUSY (client should wait and then retry). resP->eInfo.eMsg = an optional reason for the wait. resP->eInfo.eArg = the number of seconds the client should wait.

ProcessRequest()

virtual void XrdSsiService::ProcessRequest ( XrdSsiRequest &  reqRef, XrdSsiResource &  resRef  )

pure virtual

Process a request; client-side or server-side.

When a client calls ProcessRequest() the same method is called server-side with the same parameters that the client specified except for timeOut which is always set to zero server-side.

Parameters

reqRef	Reference to the Request object that describes the request.
resRef	Reference to the Resource object that describes the resource that the request will be using.

All results are returned via the request object callback methods. For background queries, the XrdSsiRequest::ProcessResponse() is called with a response type of isHandle when the request is handed off to the endpoint for execution (see XrdSsiRequest::SetDetachTTL).

Implemented in XrdSsiServReal.

Stop()

virtual bool XrdSsiService::Stop ( bool  immed = false )

inlinevirtual

Stop the client-side service. This is never called server-side.

Parameters

immed

When true, the service is only stopped if here are no active requests. Otherwise, after all requests have finished. the service object is deleted.

Returns

true Service has been stopped. Once all requests have been completed, the service object will be deleted.

false Service cannot be stopped because there are still active foreground requests and the immed parameter was true.

Reimplemented in XrdSsiServReal.

Member Data Documentation

SsiVersion

const int XrdSsiService::SsiVersion = 0x00020000

static

Obtain the version of the abstract class used by underlying implementation. The version returned must match the version compiled in the loading library. If it does not, initialization fails.

Referenced by GetVersion().

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The documentation for this class was generated from the following file:

• XrdSsiService.hh