Return to readme.pulloperations CVS log

Up to [Pegasus] / pegasus

BUG#: 9676
TITLE: TASK-PEP317_pullop-branch Compile Error, Windows

DESCRIPTION: Correct error and couple of other minor editorial issues.

        Using the CIM/XML Pull Operations

STATUS

<<< The TODO section is being maintained during the review and checkin process
to keep track of problems, errors, notes, etc.  Must be deleted before
checkin to head of tree. Please feel free to add notes, etc in this
section as you review/test.>>>>>>

TODO list:
   1. Binary operation from OOP.  Need to add counter to binary
      protocol to be able to count objects in response. Generates
      warnings in things like messageserializer and does not work with
      OOP right now.  Fixed by converting to XML. Concluded that we do not
      need to do this. The binary response is not really used often
      in the current environment So double mapping it is not a major issue.
      Leave this as FUTURE
   2. DONE OpenExecQuery - Code is incomplete in that it does not include the
      return from the exec query function to the aggregator yet. Code for Pull
      part of OpenQueryInstancesRequest a) should be part of the common
      CIMOperationRequestDispatcher execCommon code. DONE, not tested. 29 May
       30 May tested with simple cli calls.
   3. DONE The changes to WQLCIMOperationRequestDispatcher and CQL... for handling
      pull not completed so we feed the responses back to the EnmerationContext
      queues. DONE Not tested 29 May 30 May DONE,  some testing done
   4. Minor TODOs, diagnostics, etc. still in the code. Reduced almost to
      none now.  We are leaving some in as PEGASUS_DEBUG
   5. Extension to avoid double move of objects in CIMResponseData (one
      into enumerationContext queue and second to new cimResponseData for
      response.  Want to avoid second move by extending Open/Pull response
      messages to include count and CIMResponse data to count objects out
      of queue when converting (avoids the second move). This would mean
      extending the output writers to allow the count field to be supplied
      so they would only create output for up to the count supplied.(Make
      this future beyond bug 9676). This is fairly extensive because it
      extends beyond CIMResponseData to SCMO and XML writers where the
      XmlWriters used by encodeXmlResponse would have to have counters
      added. Then instead of copying on getCache we would simply pass the
      cache and count on and the writer would take and remove.
   6. Add more static tests (currently only OpenEnumerateInstances and
      OpenEnumerateInstanceNames covered). 
      Low priority because most of this except exact XML covered in other
      tests. note that we can only add very limited tests since a) no
      way to test multiple operations in sequence(i.e. open/pull) and
      cannot be sure how many responses will come back in all cases even
      for open.  The only reason for most of these tests is to assure that
      we do not change XML inadvertendtly in future with change that is
      compatible to both our server and client but breaks other clients or
      servers. In any case we can do only minimal tests because most real
      testing involves both open and pull and the static tests are by their
      nature single operation.
   8. Correct issue between operations and HTTP where we are sending
      trailers with exceptions. Modify response mechanisms so that we
      set non-chunked for all responses where we send error responses to
      avoid the trailers. NOTE: There should be now a bug on this in general
      where we would want to send an initial error without the trailer. Should
      have always done that.
   9. It would be more efficient in dispatcher to always use exception for
       rejects and change the _reject functions so that they never return
       when they reject. This is VERY LOW PRIORITY and primarily saves
       a few lines of code in the reject functions and their calls.  Means we
       would code.
       _rejectIfEnumerationToBroad(...);
       _rejectIfThisParameterIncorrect(...);

       instead of
       if (_rejectIfEnum...)
       {
           return true
       }
       It would mean that the method trace for the handlers would not return
       an exit if we rejected. VERY LOW PRIORITY. Possibly FUTURE. No behavior
       change, just more compact source code but it messes with the method
       trace logic.
    10. There are still a couple of template functions around the task of
       distributing requests to the multiple providers.
       In fact there are two similiar but different templates for
       the associators(i.e. assoc, ref, etc.) functions and the parallel
       openAssoc functions.  It would be nice to consolidate that logic and
       further to try to create a non-template form for those functions. LOW
       PRIORITY and not for bug 9676 ACTION: Define in new bug
    11. External runtime variables. bug 9676 leaves these variables as
       internal to CIMOperationRequestDispatcher.cpp.  
       See bug 9819 for the changes to externalize these variables, both
       the runtime and buildtime variables.  The Work group discussion
       documents what the variables are and how they tie to statistics info.
       See the OpenPegasus Wiki, Pull operations work group.
    12. Trace functions in CIMResponseData,h & cpp should be PEGASUS_DEBUG.
       Same for trace function in EnumerationContext and
       EnumerationContextTable
    13.Question. We added trace in CIMRequestOperationDispatcher.cpp if
       query enum is recevied with no object path.  However, since this is
       a provider problem should we be doing something other than a trace
       (ex. log) since traces are often not really used and they do generate
       lots of data whereby something like this could get lost. Also, need
       to review what level of trace if we keep trace.
   14. Note that the build-a-class argument on OpenQueryInstances always
       returns error since we do not build the class.  We propose to deprecate
       this in DMTF and not implement in in OpenPegasus. TODO add a bug
       defining this limitation. This is not a TODO, just a warning for
       the future. TODO add bug about this and add to release notes
   15. Clarify trace of completion of each enumeration sequence.
   16. Statistics keeping for open, etc. through cimperf.


   NEXT TASKS: 
      a. finish 8, 12 above. Test against cimperf since there was a bug
      in cimperf from before.

11. August 2014
1. Correct error in compile in windows (bad reference to sleep(...)

29 July 2014
1. Cleanup functionality in the unittests for EnumerationContext and
   its table.

23 July 2014
1. Mergeout from head of tree to Task branch

21 July 2014
1. Removed strings.h from pullop.cpp
2. Minor cleanup per testing

17 July 2014
1. Correct error in CIMOperationRequestDispatcher.cpp OpenQueryInstances
   when PEGASUS_DISABLE_QUERY set.
2. Correct issue in diagnostic code in CIMResponseData.cpp that used 
   snprintf function not available in windows.
3. Clean up some miscellaneous code in pullop and Makefile.
4. Minor change to PullErrosrs.

2 July 2014
1. Corrected error in the new getoopt functions that caused it to fail
   in build and also in it unit test with the --help option.

28 June 2014
1. Corrected issue where ZOs was getting errors from pullop because we
   used getopt to parse command line and the linux getopt is not behavior
   consistent with ZOs.  Note that the ZOs getopt matches the posix expect and
   the linux one has extensions (notably it permutes non option arguments to
   the end of the arguments array.  The easiest and most logical was to move
   the whole parser to use the internal getoopt which is what we should be
   using all the time in any case.
18 June 2014
1. Correct errors in pullop and CMIMessage.cpp identified by Ji Lee as comments 58,59
2. Correct error in Makefile identified by Ji Lee as bug comment 60

14 June 2014
1. Mergeout from head of tree.

12 June 2014
1. Implement the basic code for the CIMOperationDispatcher portion of bug 9819
   Note that the CIMConfig calls are disabled with comments.
2. Corrected a number of differences in const declaration and definition for
   continueOnError and maxObjectCount in CIMClient. This corrects issue
   documented in bug 9676 comment 53
3. Corrected some documentation for Pull operations in CIMClient.
4. Corrected similar issue In EnumerationContext class. See comment 54
5. Removed ExecInfo.h header from Client/tests/PullErrors/PullErrors.cpp

30 May 2014
1. Correct issue in UintArgs.  Modified to use smart pointers, consistent
   with public interfaces. Tested
2. Complete code for OpenQueryInstances and PullInstances so that the complete
   sequence works for both the server and client (i.e. 2, 3 above done
   except for more tests in pullop).
3. Fix issue in cimcli where the OpenQueryInstances was outputting a path
   component where there is no path transmitted from the server.
4. Moved large block of common code in CQLOperationRequestDispatcher.cpp
   and WQLOperationRequestDispatcher.cpp to common function
   handleQueryRequestCommon in CIMOperationRequestDispatcher.cpp. These
   handlers now reduced to just the parser processing and minimal error
   checks.
5. Cleaned up some code in EnumerationContextTable.CreateContext so only
   single interface for all requests.
6, Commented out a number of PEG_TRACE messages.  Note that they are
   commented with 4 /s at line beginning to be easily identified.
   //// code
   There are still a number of KS_TODOs but they are mostly some questsions,
   some internationalization (note that almost none of this environment is
   completely internationlaized (see the decoders)) and a couple of questions
   about the existing code or exactly what message should be sent.  I argue
   that the current TODOs should not stop checkin. Will remove after we
   have tested couple of days and prove that there is no real need.
7. Added trace in Query response code if there is no objectPath since that
   is really an error in the provider


29 May 2014
1. Correct issue in cimcli that was causing rejects of open operations when
   there were no filters requested. The standard default is WQL in cimcli
   so we overrode this for the pull operations.
2. Clean up OpenQueryInstances in CIMMessage.h and CIMMessage.cpp.
3. Modify CIMOperationRequestDispatcher and
   EnumerationContextTable.CreateContext to pass request rather than request
   parameters.
4. Remove a number of diagnostic messages.  Note that there are still some.
   They are marked KS_TODO with with note to remove before checkin. They are
   all traces and validations.
5. Correct error in inclusion of execinfo.h include in CIMOperationRequestDis.
   found by Ji Lee.
6. Cleaned up execQuery and extended it for OpenQueryInstances.  ExecQuery
   tested but have not tested OpenQueryInstances yet. One more checkin and we
   should be able to close 2,3 above (OpenQueryInstances).

26 May 2014
1. Remove a number of diagnostics.
2. Make cache size in EnumerationContextTable dynamic and remove function
   to set default values. MaximumEnums set from Dispatcher on constructor for
   EnumerationContextTable and table size set to 1/2 of maximum number of
   open contexts.
3. Clean up some statistics in EnumerationContextTable
4. Correct error in query and queryLanguage parameters in cimcli in that
   the default for queryLanguage is WQL but must be "" for pull operations.
   If WQL found they set it to "".


9 May 2104
1. Converted several  template functions in CIMOperationRequestDispatcher
   to real functions
2. Added intermediate CIMMessage for CIMPullOperationRequestMessage since
   all of the pulls have exactly the same data. This allowed us to
   convert the template function processPullRequest from template to
   real function
3. Added intermediate CIMMessage for CIMOpenOperationRequestMessage betweeh\n
   all of the Opens and the  CIMRequestData message.  This will allow
   common code to test all of these variables in all 6
   CIMOperationRequestDispatcher handleOpen... functions
3. Added variable in  CIMOperationRequestDispatcher handleEnqueue to make
   releasing the original request conditional on return from the handle... 
   for open... and pull... handlers.
   This allowed us to drop one place where we were creating a new request msg
   for the delayed response and use the original request.  This meant that
   we could convert the issueOpenOrPullResponse from template function to
   real function.
4. Moved open and pull constructors in CIMMessage.h to CIMMessage.cpp. NOTE:
   openQueryInstances not moved.  Will do when we get this funciton running.
5. Added test for correct namespace in pull operations.  Note that it is
   never really used but since supplied with request, we test to be sure it is
   same as open request namespace.  added internationalized exception for this.
6. We should probably add same test to close just as an input parameter
   validation.  
6. Modified processPullRequest to close the enumeration context if
   incorrect response type received.  Before we just returned exception and
   left context open for next request.  Closing is much more logical since the
   client really did send an erronous request.
7. Modified PullErrors to correctly test above changed in behavior.
8. Removed a significant number of diagnostic messages.
9. Added query and querylanguage parameters to cimcli.


4 May 2014
1. Clean interface with EnumerationContext timeout thread
2. Remove more diagnostics
3. Correct issue with enumerationContext Release that was causing
   failures during nightly tests.

2 May 2014
1. Remove Diagnostics from ResponseData.cpp
2. Correct setup and start of EnumerationContextTimerThread
3. Change limit on max number of enum contexts to be set from Dispatcher.
4. Increase size of hashtable for enum contexts.
5. Corrected issue causing failures in removeContext. Now runs through nightly
   tests most of the time.
1 May 2014
1. Cleanup of code and variable names.
2. Removed namespace variable from EnumerationContext.  It was never used.
3. Added test for max number of open enumerations.  Right now it is fixed
   and set about 100. Note that this is tied to the size of hash table
   so that there is a issue with more dynamic setting of max and the
   hash table size.
4. Removed several unused functions.
5. Found one possible issue causing thread conflict but not the core one
   yet.  

30 April
1. Added exception response to dispatcher for Limits exceeded on
   CreateEnumerationContext. Returns Exceeded server limits CIMException.
2. Fixed possible deadlock where we were not unlocking EnumerationContext
   under error condition


27 April - mergeout to head of tree
1. Mergeout of the code to the head of tree. Documented that mergeout in
   the bug

27 April 2014
1. Clean up in a number of areas, mostly just code without changing
   functionality.
2. Modified CIMMessage.h slightly to clarify names of the pull intermediate
   messages (the common open and pull response);
3. Removed a number of diagnostics from CIMResponseData
4. Added new function to ResponseStressTestProvider to be able to terminate
   output after a defined number of objects with a CIMException.
5. Removed a number of other TODOs
6. Corrected a couple of errors in the server message bundle.
7. Modified ResponseEncoder to only output the error for pull errors.
   It was errounously outputting the EndOfSequence, EnumerationContext and
   the error.  This way, only the error is sent which is spec.
8. Removed number of TODOs and cleaned up a couple of others.
9. Added static tests for OpenEnumerateInstanceNames.
10. Modified a number of the temporary diagnostics to be permanent by
    changing them to PEGASUS_DEBUG_ASSERTs

22 April 2014
1. Clean up some messages.
2. Still trying to find issue that randomly keeps messages in timeout
   queue long after they have been closed and returned.
3. Fixed memory loss error.
4. Added zero reject for OperationTimeout because that effectively disables
   the whole timeout mechanism so that enumerations could be started, never
   completed by the client and would just hang around in memory. That
   would be a significant DDOS attack (start very large enum with no
   timeout) and never do pulls after open.

21 April 2014
1. Reorganized code in CIMOperationRequestDecoder.cpp ...Iparam classes.
   Cleaned up the rejectCIMException code.
2. Cleanup some issues in the EnumerationContextTimeout Thread.
3. Fixed issue in pullop where it was using zero as default for default
   operation timeout where it should have been NULL, the DMTF specified
   default.
4. Enabled the test to reject 0 as operation timeout on a request and but
   controled by a #define in CIMOperationRequestDispatcher.cpp
5. Added test for excessive new OperationContext entries in table.

18 April 2014
1. Internationalize remaining messages in CIMOperationRequestDecoder.cpp and
   clean up the decoders for some of the messages so they use the
   ...Iparam classes.  Note that we did not clean up all of the old message
   decoders, just the new ones and we did not clean up the Count message
   since it is deprecated. TODO clean these up so the decoder is really
   consistent.
2. Enabled the EnumerationContext Timer and removed code for alternate
   non-thread solution.

17 April 2014
1. Reorganized the lock/unlock for handling the EnumerationContext because
   there were thread windows (i.e. using the context after it was released
   by other thread).
2. Modified code for the InteroperationTimerThread and deleted old code that
   allowed this whole thread to by bypassed.
3. Internationalized a number of CIMOperationRequestDispatcher CIMException
   response messages.
4. Fixed stress tests in Client/tests/pullop that were getting timeout. The
   issue was not the pull code but that fact that the idle client timeout
   appears to be measureing to the end of the operation and the operation
   was taking more than 40 seconds which is the default timeout. The idle
   timeout takes no account of the fact that chunks are being regularly
   delivered.
5. Several minor code changes.
NOTE: At this point the code passes extensive tests of the pull operations
   both in OOP and none OOP mode (but with lots of diagnostics that may
   be affecting timing).

10 April 2014
1. Fix issues causing failure with repeated pull operations.
2. Consolidate some of the CIMOperationRequestDispatcher.cpp template code

7 April 2104
  MergeOut of head of tree.

7 April 2014
1. Permanently fixed issue with getting correct number of objects on response.
   This was introduced when did a temp fix to the OOP processing, in particular
   removed the condition variable wait in the CIMOperationDispatcher handle
   functions for opens and pulls.  This moved the functionality to kick off
   open and pull responses to the provider threads if there are not enough
   objects when the handle is processed. Also added a variable to allow us to
   test with either a) responses are required to satisfy the original 
   request size or) b, responses are required only to return some objects.
   We will add statistics to see which of these works best.
2. Modified WsmProcessor EnumerationContext class since the name conflicts
   with the pull Operation EnumerationContext class.
3. Created a new intermediate level of CIMMessage, the CIMPullResponseData
   Message so that all of the open and Pull responses can use common code
   since there are only two variables (endOfSequence and EnumerationContext)
   and they are common across all the open and pull responses.
4. Removed a number of diagnostics.
5. Cleaned up the Dispcatcher so that the open and pulls have common response
   code and that code can be used from the dispatcher handle functions and
   the provider response functions.

31 March 2014 - Checkin
1. Fixed issues in OOP processing of pull operations, in particular
   issues with cimxml output format when processed through the
   *InternalXmlEncoder functions.
2. Clean up some of the internalXml functionality
3. Found issues causing timeout with a particular provider.  The issue
   is that the dispatcher and monitor end up using the same thread so the
   condition variable in the dispatcher thread stops the monitor. Turned
   off the conditionVariable in getCache for the moment which means that
   we get number of responses for open... with 0 objects before the
   providers can begin to respond.  This is only for test.
4. Added some statistics for enumerations and display the statistics 
   when we close the server (same as cache statistics)

12 March 2014 - Mergeout and Mergein
1. Mergeout to head of tree for this date and mergein for patch update
   to bug 9676
2. Extensions to pullop tests program and tests.
3. Added some diagnostics in looking for OOP issue.
4. Removed a number of diagnostics messages and cleaned up code in
   dispatcher to simplify pull operation processing.

15 December 2013
1. Mergeout and mergein up to 15 December 2013
2. Clean up issues from tests documented in bug 9676 last week.
3. Clean up some code in dispatcher
4. Remove the filter function from ResponseStressc++Provider.

21 November 2013
1. Mergeout from head of tree to 21 November 2013.

18 November 2013
1. Cleanup of a bunch of minor errors and completion of all of the code for
   the openQueryInstances except for the PullInstances in Dispatcher and
   the aggregator function.
2. OpenqueryInstances added to cimcli.

13 October 2013 CVS branch update.
1. Integrated bug 9786 into the branch.  Note that we need to test the
   generated statistics.
2. Mergeout executed to update to head of tree as of 8:00 am 13 October 2013.
3. Cleaned up several errors in OOP processing.  Note that there is at least
   one issue left when we to a pull on ManagedElement in at least one of the
   namespaces.
4. Cleaned up some of the outstanding diagnostic code
5. Generally passes all tests except for one test of pullop where it is trying
   to pull enum instances CIM_ManagedElement from a particular namespace.

NOTE: I did not make comments here for changes in October despite the fact
that I did 2 mergouts, number of fixes, and a mergein.

30 September 2013 - CVS Update
Mergeout head of tree up to 29 September 2013.

29 September 2013. CVS update.
1. Modified calls to statisticalData.cpp to a) directly call with request
   type, b) incorporate the open, pull, etc. messages.  However, since these
   are not part of the CIM class, we must do something special with them.
   See bug 9785 for full solution to this issue.
2. Corrected OOP interface to enable new flag to indicate internal operations
   and set host, etc.
3. Add code to CQLOperationsDispatcher and WQLOperationDispatcher to clean
   up CIMResponseDataCounter after filtering.
4. Modified ProviderAgent to set Host info for some pull operations.
5. Added new flag to CIMBinMsgSerializer and Deserializer.

17 September 2013 CVS update (Actually two different updates over 3 days)
1. Clean up some issues in CIMMessage.h and CIMMessage.cpp
2. Extend OpenExecQuery to WQL and CQL processors but return not complete
3. Remove memory leak in EnumerationContext and EnumerationContextTable
   handling.
4. Created template functions for much of the pull operations.
5. Reversed order of queryLanguage and query (and changed names to match
   execQuery) in client and server.  Note that these are the execQuery
   WQL and CQL filters and NOT FQL filters.
6. Some code cleanup in dispatcher
7. Today, passes all tests in pullop but issue in alltests. For some reason
   not finding CIMObjectManager instance. Also, leaves enumeration contexts
   if client terminates since cleanup thread not operating.
8. XML from OOP not correctly processed.

14 September 2013 CVS update
Merged out up to 25 August.  Cleaned up all operations and standardized code.
At this point the non pull operations code is in a set of templates but the
pull is not yet.
Fixed a significant number of problems so that it appears that the operations
except for OpenExecQuery run stably, at least with the pullop test program.
Note that there is a problem in that the Interop control provider is not
returning its singleton wbemserver object for some reason.  Causes a test
failure

Fixed for 16 June CVS Update
   1. Cleaned up the enumerationContext and Table release functions and tested
      to confirm that we do not lose memory in either normal sequences or
      sequences that close early. Cleaned up pullop and added more tests
Taged Before: PREAUG25UPDATE and after POSTAUG25UPDATE

Fixed for 9 June CVS update
   1. Cleaned up code for OpenQueryInstances.  Note that this is incomplete.
      No support in WQL or CQL Operations
   2. 

What was fixed for 5 June checkin.
   1. Extended ResponseTest MOF for for both CMPI and C++ subclasses
   2. Fixed issues with pullop.
   3. Fixed temp issue with CIMResponseData size by putting in mutex. That
      is not a permanent fix but it gets around issue probably in the control
      of the move logic that meant counts were off.
   4. Fixed issues in Dispatcher so that associator code works. Still messy
      code in the dispatcher.
   5. Changed name of Enumerationtable.h & cpp to EnumerationContextTable.*
   6  Changed name of ResponseStressTest module, classes, etc.

TAG: TASK_PEP317_5JUNE_2013_2

2 June 2013

Issues  - KS

 - Still way to many TODO and KS comments and KS_TEMPS.  Removing bit by bit.

 - Runtime variable connection for the config parameters not installed. That
   has been made into a separate bug (see bug 9819)

5. Issue with the threaded timer.  For some reason during tests it
eventually calls the timer thread with trash for the parm (which is
pointer to the EnumerationTable object). Caught because we do a valid
test at beginning of the function.

6. Still using the templates in CIMOperationRequestDispatcher to simplify
the handle... processing.  

7. I think I have a way around the double move of objects in the
EnumerationContext so that the outputter will just take a defined number
of objects directly from the gathering cache and save the second move.

8. Not yet passing all tests but getting closer now. The major test that is
causing an error today is the execution of a full enumeration with the
forceProviders = true.  This causes a client timeout sometimes.



===========================================

OVERVIEW:

The operation extensions for pull operations defined in the DMTF specification
DSP0200 V 1.4 were implemented in Pegasus effective Pegasus version 2.11
including Client and Server.

These operations extend the CIM/XML  individual operations to operation
sequences where the server must maintain state between operations in a
sequence and the client must execute multiple operations to get the full
set of instances or instance paths.

The following new CIM/XML operations as defined in DSP0200 are included;

    -OpenEnumerateInstances
    -openEnumerateInstancePaths
    -OpenReferenceInstances
    -OpenReferenceInstancePaths
    -OpenAssociatiorInstances
    -OpenAssociatorInstancePaths
    -OpenQueryInstances
    -PullInstancesWithPath
    -PullInstancePaths
    -PullInstances
    -CloseEnumeration
    -EnumerationCount
     OpenExecQuery

The following  operations have not been implemented in this version of Pegasus:

    -OpenQueryInstances

The following limitations on the implementation exist;

1. The filterQueryLanguage and filterQuery parameters are processed by
   the Pegasus client but the server returns error if there is any data in
   either parameter. This work does not include the development of the
   query language.  Note that a separate effort to extend Pegasus to use
   the DMTF FQL query language is in process.

2. The input parameter continueOnError is processed correctly by the client
   but the Pegasus server only provides for false since the server does not
   include logic to continue processing responses after an error is
   encountered. 
   This is consistent with the statement in the specification that use of 
   this functionality is optional and the fact that the DMTF agrees that all 
   of the issues of continuing after errors have not been clarified.  

3. The operation enumerationCount is not processed by the server today since
   a) really getting the count would be the same cost as the corresponding
   enumeration, b) the server does not include a history or estimating
   mechanism for this to date.
   NOTE: After a through review as part of the development of the next version
   of CMPI we have concluded that this operation is probably not worth the
   effort.  Since it is optional, Pegasus will only return the unknown status
   at this point

Since the concept of sequences of operations linked together (open, pull, close)
is a major extension to the original CIM/XML operation concept of completely
independent operations several new pieces of functionality are implemented
to control interOperationTimeouts, counts of objects to be returned, etc.

TBD - Review this

CLIENT

The new operations follow the same pattern as the APIs for existing operations
in that:

1. All errors are handled as CIMException and Exception

2. The means of inputting parameters are the same except that there are
   significantly more input parameters with the open operations and for the 
   first time operations return parameters as well as objects in the 
   response.  Specifically the open and pull operations return values for 
   enumerationContext which is the identity for a pull sequence and 
   endOfSequence which is the marker the server sends in open and pull 
   responses when it has no more objects to send.

The significant differences include:

1. Processing of parameters on responses (i.e. the endOfSequence and
   enumerationContext parameters are returned for open and pull operations).

2. Numeric arguments (Uint32 and Uint64 include the option of NULL in some
   cases so they are packaged inside classes Uint32Arg and Uint64Arg in the
   client api.

3. The association and reference operations ONLY process instances.  They do
   not include the capability to return classes like reference and associator
   do and therefore return CIMInstance rather than CIMObject.

4. Paths are returned in all cases (i.e OpenEnumerateInstances and
   PullInstancesWithPath where they were not with EnumeratInstances.

5. The client must maintain state between operations in a sequence (using
   the enumerationContext parameter).

TBD- Are there more differences.


SERVER

The Pegasus server attempts to always deliver the requested number of objects
for any open or pull request (the specification allows for the server to
deliver less than the requested number of objects and specifically to return
zero objects on open).  We felt that it was worth any extra cost in processing
to provide the client with exactly what it had requested.

The pegasus server always closes an enumeration sequence upon receipt of any
error from the providers, repository, etc. Therefore the server will reject
any request that has continueOnError = true;

Expansion to allow the continue on error may be added in a future version.
In any case, the whole purpose of the continue on error is really to allow
input from good providers to be mixed with providers that return errors so
that generally this would mean simply changing the logic in the return mechanism 
to not shutdown when an error is received from any given provider.

Generally we do not believe that the providers need to do much more in the
future to support the continueOnError other than possibly allowing the provider
to continue processing after it has received an error.

PROVIDERS

This implementation requires NO changes to the existing providers.  The
provider APIs operate just as they do with the original operations.

Because the server processing is different however, there may be some
behavior differences primarily because the client now controls the speed of
delivery of objects.

In previous versions of Pegasus, the server attempts to deliver objects as
rapidly as then can be put on the network.  In the case of HTTP chunked requests
they are delivered in chunks of about 100 objects. The primary delay for the
providers was the processing of each segment through the server.  The server
is blocked so that no other segment can proceed through the server until that
segment is processed and sent on the network.
In the case of non-chunkedresponses, they are completely gathered in the serve
and then delivered as one non-chunked response. There were no delays for the
providers, just lots of possible memory use in the server.

The responses from providers (delivered through the deliver(...) interface are
gathered into segments of about 100 objects and this group of objects is moved
through the server to be delivered to the client.

However with the inclusion of the pull operations,   The segments of objects
from the providers are cached in the server response path until the 
maxObjectCount for that request (open or pull) and that number returned in a
non-chunked response. Thus, if the client is slow to issue pull requests,
the providers might be delayed at some point to reduce memory usage in the
server (the delay appears as slow response tothe deliver operation).

In other words, the time to process large sets of responses from the provider
now depends on the speed of handling the client.

It is important to remember in developing providers that the Pegasus server
can most efficiently process responses if they are passed from the provider
to the server individually or in small arrays of objects rather than the
provider gathering very large arrays of objects and sending them to the
server.

NEXT GENERATION PROVIDERS
KS_TODO

CONFIGURATION PARAMETERS

The server includes several configuration parameters to set limits on the
processing of pull operations.  All of these configuration parameters are
compile time parameters rather than runtime.

1. Maximum value of minimum interoperation time.  This parameter defines the
maximum time allowed between the return of an open or pull response and 
the receipt of the next pull or a close operation before the server may 
close the enumeration.  The specification allows the server to set a 
maximum interoperation time and refuse open requests that with requested 
operationTimeout greater than that time.  
CIM_ERR_INVALID_OPERATION_TIMEOUT

This value is set with the Pegasus environment variable
PEGASUS_PULL....

2. Maximum objects returned in a single open or pull operation.  The server
can set a maximum limit on the number of objects that can be returned in
a single open or pull oepration with the maxObjectCount parameter.

3. Whether the server allows 0 as an interoperation timeout value. The value
zero is s special value for the interoperationTimeout in that it tells the
server to not timeout any enumeration sequence.

With this value for interoperationTimeout, the only way to close an 
enumeration sequence is to complete all of the pulls or issue the close.  
If for some reason the sequence is not completed, that enumeration context 
would remain open indefinitly.  Since in Pegasus any open enumeration 
context uses resources (the context object and any provider resposnes that 
have not yet been issued in a response) it would appear that most 
platforms would not want to allow the existence of enumeration contexts 
that cannot be closed by the server.  

4, maximum consecutive pull requests with 0 maxObjectCount.  The use of the
pull operation with maxObjectCount set to zero could be used to keep an
enumeration context open indefinitly (this tells the server to restart the
interoperationTimeout but not send any objects in the response). Therefore the
specification allows for the server setting maximum limits on this behavior
and returning the error CIM_ERR_SERVER_LIMITS_EXCEEDED if this limit is
exceeded.
Note that this is maximum CONSECUTIVE pulls so that issuing a pull with
a non-zero count resets this counter.

KS-TBD - Is this really logical since we can still block by just issuing
lots of zero request and an occansional request for one object.

Pegaus sets the value of this limit to 1000 and allows the implementer to
modify it with the PEGASUS_MAXIMUM_ZERO_OBJECTCOUNT environment variable.

5. Default operationTimeout - 

The default of this parameter is to refuse operat

In the current release of Pegasus these are all compile time parameters.


NOTES On working with task branch.

Merge out Process

   To keep our TASK branch in sync with the current head of tree we need
   to do a regular merge out.  the TaskMakefile contains the makefile
   procedures to do this efficiently.  NOTE: Following these procedures is
   important in that you are merging out new material each time you do
   the merge out.  If you were just to repeatedly merge out, you would be
   merging previously merged changes a second time causing a real mess.

    Start with new directory and put TaskMakefile above pegasus (needed so you
    have this file for the initial operations.  

      make -f TaskMakefile branch_merge_out BNAME=PEP317-pullop  ## takes a long time

   This checks out current head, merges it into task branch and sets tags
   for the mergeout.  Note that at the end of this step this work is
   part of the TASK... branch.

   NOW check for conflicts, errors, etc. that resulted from the merge.
   Look for conflict flags, compare the results (I use linux merge as a
   good graphic compare tool) and build and test. When you are satisfied
   that the merge out is clean, you can commit the results to the TASK...
   branch
   
   To commit the work to  this into Task branch

      make -f mak/TaskMakefile branch_merge_out_commit BNAME=PEP317-pullop

  or manually commit and finish as follows

    cvs commit
    make -f mak/TaskMakefile  branch_merge_out_finish BNAME=PEP317-pullop

## This last step is important since it cleans up temporary tags to prepare
   you for the next checkout
   
COMPARE TASKBRANCH WITH HEAD

    In a new pegasus work space do same as above for merge out.

    make -f TaskMakefile BNAME=PEP317-pullop

    This produces a result which is all of the head merged into the branch.
    A diff of this is all the new changes to the head of tree that you will
    include into the merge.