Open Grid Forum: Data Format Description Language Working Group

OGF DFDL Working Group Call, April 14-2010

Attendees
Steve Hanson (IBM)
Alan Powell (IBM)  
Steve Marting (Progeny)  
Stephanie Fetzer (IBM)
Suman Kalia (IBM)
Tim Kimber(IBM)

Apologies
Mike Beckerle (Oco)


1. DFDL Specification status
After a slight delay the DFDL v1 Specification was opened to public comment on April 15th until June 15th.
There was some discussion about publicizing the review. Steve H mentioned he started the process for getting approval for IBM to be included in a press release. Steve M indicated that Progeny may also be willing.
Steve M mentioned that Progeny were working on an OMG mediation framework that requires DFDL and theat Progeny will have at least a partial implementation of DFDL that may satisfy the OGF requirement.


2 Nils, defaults and unparsing  
Tim had distributed some uses cases of fixed and delimited formats with initiated and non-initaited element. The was considerable discussion of the initiated, delimited cases

ONE:one,THREE:three<END>
ONE:one,,THREE:three<END>

The discussion was mainly about whether was any difference in intent between missing and zero length in these examples and whether zero length string or default should be inserted into the infoset, Tim suggested using separatorPolicy required as a trigger. Alan pointed out that the table in the spec used the presence or absence of a default value to decide is the default or empty string should be the result.  Eventually concluded that an additional property may be needed and a proposal will be developed.

In addition it was noted that the interaction between dfdl:initiatedContent and dfdl:missingValueInitiatorPoilcy may need clarifying.
It was also question whether XSDL allows the empty space to be specified as a default value.

3 dfdl:separatorPoilicy.

The main discussion was about how to detect when complex types should be defaulted which was similar to the defaulting discussion for simpleTypes. The added complication for complex types is that the content region is the children so should you detect missing by parsing the first child? It was agreed that examples simpler to the ones above would be helpful.

Meeting closed, 14:45

Next call  Wednesday 21 April January 2010  13:00 UK  (8:00 ET)

Next action: 091

Actions raised at this meeting
No
Action

Current Actions:
No
Action
066
Investigate format for defining test cases
25/11:IBM to see if it is possible to publish its test case format.
04/12: no update
...
17/02: IBM is willing in principle to publish the test case format and some of the test cases. May need some time to build a 'compliance suite'
24/03: No progress
03/03: Discussions have been taking place on the subset of tests that will be provided.
10/03: work is progressing
17/03: work is progressing
31/03: work is progressing
14/04: And XML test case format has been defined and is being tested.
084
Check behaviour of dfdl:inputValueCalc and outputValueCalc.
14/04: no prorgess
085
ALL: publicize Public comments phase to ensure a good review..
14/04: see minutes
086
AP: Nils and Defaults during unparsing - update table
31/03: TK to documetn use cases for parsing
14/04: Investigate new property to control empty string behaviour.
088
define semantics of choiceKind 'fixedLength'
31/03: TK to provide definition of calculable length.
Investigate  PL/I varchars and Cobol occurs dependingon.
14/04Tim had distributed a document starting the definition of calculable length for the longest choice member.
Alan had done some investigation of COBOL occurs depending on and when used in the working section of a program then the maximum storage was reserved but when used in the linkage section the dependent number was uses. We need to understand how the WMB COBOL importer deals with ODO.
089
Need to be able to define unsigned decimal and integer
31/03: MB to agree proposed solution
14/04: MB to agree proposed solution
090
Semantics of separatorPolicy
14/04: Discussion on detecting when complex types should be defaulted. Examples needed.

Closed actions
No
Action

Work items:
No
Item target version status
005
Improvements on property descriptions not started
012
Reordering the properties discussion: move representation earlier, improve flow of topics not started
036
Update dfdl schema with change properties ongoing
042
Mapping of the DFDL infoset to XDM none not required for V1 specification
070
Write DFDL primer
071
Write test cases.
083
Implement RFC2116
097
Remove functions that returns duration
098
occursCountKind is parsing only


 
Regards
 
Alan Powell
 
Development - MQSeries, Message Broker, ESB
IBM Software Group, Application and Integration Middleware Software
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