Open Grid Forum: Data Format Description Language Working Group OGF DFDL Working Group Call, June 02-2010 Attendees Steve Hanson (IBM) Alan Powell (IBM) Stephanie Fetzer (IBM) Apologies Tim Kimber(IBM) Suman Kalia (IBM) Mike Beckerle (Oco) 1 Nils, defaults and unparsing Continue review proposal emailed by Alan The proposal was not discussed on the call. Please send comments to Alan by next Monday. Stephanie sent an email discussing whether using discriminators had any effect on defaulting using a COBOL occursDependingOn example. It seems as though there is not a problem. However the discussion prompted questions about how occursCountKind effected defaulting. In particular if the occureCountKind is expression referring to another field in the data which doesn't match the number of occurences is it an error should defaulting occur?. Action raised to follow up. 2 OGF 29 Chicago, June 20-22 Suman was unable to get authorization to attend. 3 Current Actions Updated below 4 Trailing alignment with lengthKind delimited or endOfParent Is it sensible to allow Trailing skip bytes with LK delimited The grammar says that trailing alignment is applied before the separator So the parser must search for the separator then remove the trailing bytes from the value and length. @Data1 *Data2*# - Test1 value=Data1 length=5 @Data1*Data2*# - Test1 value=Da length=2 (do we require that the trailing data must be the fillByte?) But bear in mind that the grammar effectively says: RightFraming = Terminator TrailingSkipBytes So the combination of dfdl:lengthKind="delimited" & dfdl:trailingSkipBytes would work when the delimiter is a terminator Steve was keen that there was consistent behaviour over different lengthKinds so that we shouldn't just disallow trailingSkipBytes for delimited. We discussed allowing TSB when terminator was specified. Alan to propose wording. 5 More on bit oriented formats Steve has been looking at a bit oriented format from the space industry The 'unused' fields could be defined as hidden or as leading/trailing skip bytes of a nearby field. But LSB and TSB are specified in bytes only. Steve proposed that LSB and TSB should be renamed leadingSkip and trailingSkip and can be specified in bits or bytes as specified by alignmentUnits or a new property skipUnits 6 separatorPolicy with optional fields and variable arrays. In particular: - separatorPolicy 'required' with variable arrays - supressAtEnd with required fields that have defaults. Meeting closed, 16:00 Next call Wednesday 09 June 2010 15:00 UK (10:00 ET) Next action: 094 Actions raised at this meeting No Action 092 AP: Confirm behaviour of defaulting with various occursCountKinds 093 AP: Describe trailingSkipBytes for delimited formats. 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. 21/04. Schema for TDML defined. Need to define how this and the test cases will be made public 05/05: Work still progressing 12/05: Work still progressing 02/06: Work still progressing on technical and legal considerations 085 ALL: publicize Public comments phase to ensure a good review.. 14/04: see minutes 21/04: Press release, OMG and other standards bodies. 05/05: Alan and Steve H have contacted other standards bodies. Will ask them to add comments on spec 15/05: still no public comments 02/06: No public comments 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. 21/04: After investigation a new property is not required. New rules developed and tables updated. Need examples of complexTypes to confirm tables apply. Review Nils, defaulting spec section. 05/05: Discussed defaulting complex elements. Tables updated but need to add terminator. SH; to confirm WMD behaviour when infoset item has no value on unparsing Need to describe defaulting choices. 15/05: More discussion. Alan updating sections 26/05: Discussed draft updates. Stephanie to confirm asserts do not make an element required. Alan will update draft.. All: review rest of draft. 02/06: Alan updated description. Please review. Discussed Stephanie's example using discriminators. Decided no changes needed. 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. 21/04: Need to define 'calculable length' and WMB importer ODO behaviour. 05/05: TK: Still need definition of calculable length. SKK: WMB COBOL imported behaviour with ODO 15/05: Suman sent an expmle of an imported Cobol ODo which suggested that the maximum space was reserved. He will extend the example. 02/06: no progress 092 AP: Confirm behaviour of defaulting with various occursCountKinds 093 AP: Describe trailingSkipBytes for delimited formats. Closed actions No Action 084 Check behaviour of dfdl:inputValueCalc and outputValueCalc. 14/04: no prorgess 21/04: no progress 05/05: no progress 26/05: Alan has looked at the precedence tables and the look OK. Suggest closing. 02/06: Closed 091 The IBM team had questioned whether timezones should be just UTC+/- offset or should GMT and other short time zones be allowed. Alan to investigate 15/05: Alan to talk to Ruth. 26/05: Ruth confirmed that it was only the offset from UTC or GMT. For DFDL purposes thates are the same. Suggest closing. 02/06: 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 097 Remove functions that returns duration 041 098 occursCountKind="expression" is parsing only 041 099 nilValue and OccuresStopValue cannot have an expression. On unparsing only outputValueCalc can have a forward reference. 041 100 Need to state in 4.1.2 Infoset that value is optional. 041 101 When dfdl:textNumberRep is ?zoned? only the pattern for positive numbers is used. Only the following pattern characters may be used: '+' MUST BE present at the beginning or end of the pattern to indicate whether the leading or trailing digit carries the overpunched sign, if the logical type is signed '+' MAY BE present at the beginning or end of the pattern to indicate whether the leading or trailing digit carries the overpunched sign, if the logical type is unsigned 'V' MAY BE used to indicate the location of an implied decimal point '0' indicates the number of required digits (including overpunched). '#' indicates the number optional digits. 041 102 Also textNumberPolicy implies it applies to zoned, but doesn't state what zoned behaviour it covers. I think it should be consistent with binaryNumberCheckPolicy for packed, and control whether positive punched data is accepted or rejected when parsing an unsigned type, and whether unpunched data is accepted or rejected when parsing a signed type. 041 103 - textStandardBase - textStandardGroupSeparator - textStandardExponentCharacter - textStandardInfinityRep - textStandardNanRep - textStandardZeroRep - textZonedSignStyle 041 104 4 Unsigned decimal Proposed solution: - Allow xs:nonNegativeInteger which enables unsigned unbounded integers to be modelled. The problem to solve is then just for xs:decimal. - Call the new property dfdl:decimalSigned. It only applies to xs:decimal or user defined restrictions thereof. It applies to all physical decimals, as its name implies (not just zoned or packed). 041 Regards Alan Powell Development - MQSeries, Message Broker, ESB IBM Software Group, Application and Integration Middleware Software ------------------------------------------------------------------------------------------------------------------------------------------- IBM MP211, Hursley Park Hursley, SO21 2JN United Kingdom Phone: +44-1962-815073 e-mail: alan_powell@uk.ibm.com Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU
