Open Grid Forum: Data Format Description Language Working Group

OGF DFDL Working Group Call, March 10-2010

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

Apologies
Mike Beckerle (Oco)

1. Spec issues

documentFinalTerminatorCanBeMissing:
Let's try to avoid creating another property for the postfix separator scenario. I think this property provides a way of modelling the data naturally.
We can recommend use of infix-with-a-terminator rather than 'postfix' if the final terminator can be missing.
WG deferred any changes the property at this stage



dfdl:lengthKind endOfParent
'endOfParent' has almost the same meaning as 'delimited' so should have the same semantics.
·        the item’s terminator (if specified)
·        an enclosing construct’s separator or terminator
·        the end of an enclosing construct designated by its known length
·        the end of the data stream
The effect would be the the element could be ended by the nearest known length parent not just the immediate parent. Also the immediate parent could have lengthKind 'implicit'

Agreed with the definition and that dfdl:lengthKind 'endOfParent should apply to simpleTypes only.

dfdl:lengthUnits 'characaters'
LengthUnits 'characters' is currently for simple representation 'text' only. Should it be allowed for complex?
Agreed dfdl:lengthUnits should be allowed on complex elements. The characters are in the encoding of the complex element. The endocings of the children must be the same as the parent..

Selectors
Should they be moved to an appendix.
Agreed should moved

DFDL Expression Syntax
Value comparison operators are 'eq' 'lt' 'gt' etc not '=' '<' '>' because these were defined poorly in XPATH v1 and replaced in XPATH V2. Unfortunately most examples us '=' etc
The examples need changing and '=' '<' will not be accepted

Syntax of expressions in string literals.  Add

The syntax rules for expressions are
·        Must start with a '{' in the first position and end with '}' in the last position.
·        '{' in any other position if treated as a literal
·        '}' in any position other than the last position is treated as a literal.
·        '{{' as the first characters are treated as the literal '{' and not a DFDL expression.


IgnoreCase
Should ignoreCase apply to numberInfinityRep and numberNaNRep
Agreed

Escapes.
Should escapeCharacter, escapeEscapeCharacater etc allow DFDL expressions.
Agreed

OutputNewLine should allow an expression
Agreed

Clarify dfdl: InputValueCalc and outputValueCalc
It is a schema definition error if both inputvalueCalc and outputValueCalc are specified.
InputValueCalc is examined on unparsing so needs to be added to unparsing property precedence.

Action to review inputValueCalc and putputValueCalc
 
2. Current Actions:
Updated below  

3 Status of specification  (for OGF28)
Draft 40 will be published by tomorrow and submitted to OGF on friday.


Meeting closed, 14:10

Next call  Wednesday 10 March January 2010  13:00 UK  (9:00 ET)
NOTE: East coast is 4 hours behind the UK for the next two weeks

Next action: 085

Actions raised at this meeting
No
Action
084
Check behaviour of dfdl:inputValueCalc and outputValueCalc.

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
09/12: no update
16/12: reminded dent to project manager
23/12: SH will send another reminder.
06/01: Another reminder will be sent
13/01: no update
20/01: no update
27/01: no progress
29/01: no progress
03/02: IBM is still investigating
10/02: IBM is still investigating
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
084
Check behaviour of dfdl:inputValueCalc and outputValueCalc.

Closed actions
No
Action
080
AP:Clarify semantics of fn:poisition and fn:count
17/02: no progress
24/03: No progress
03/03: no progress. There are other functions which return a duration which need investgating
10/03: changed to dfdl:position and dfdl:count. closed

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



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