VODML < IVOA

---+ VO Data Modeling Language Specification

Current WD:
   * _VO-DML: a consistent modelling language for IVOA data models_ ([[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/doc/VO-DML-WD-v1.0.docx][docx]], [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/doc/VO-DML-WD-v1.0.pdf][pdf]])
The documentation collaborative page, including ongoing versions and other documentation, is located at [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/doc][volute]] although this should not be used as an official reference

Schema files providing normative definitions vor valid VO-DML/XML files can be found here:
   * XML schema (XSD) for main structure of document: https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/xsd/vo-dml-v1.0.xsd
   * [[http://www.schematron.com/][Schematron]] for extra rules that cannot be (easily) implemented in XSD: https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/xsd/vo-dml.sch.xml
[GL 2014-04-25: I will try to keep track of comments from the mailing list on [[VoDmlWGComments][this page]]

A set of data models created according to the specification can be found on volute as well in the [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/][dm/vo-dml/models]] folder. Of special relevance for this specification are
   * ivoa: a core model defining various primitive types as well as quantity types. This model should be reused by all other models.
   * photdm-alt: a version of the [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/photdm-alt][photdm]] data model, should be synchronized with that spec.
   * source: TOY model for describing astronomical sources. ONLY used in the VO-DML and UTYPE specs for illustrating the various modelling and mapping concepts. The real source model is still ongoing.
We have made a first superficial pass at porting other IVOA data models to VO-DML, in particular characteriation, stc, simdm. These can be used as starting points for a more formal IVOA DM effort to create VO-DML representations for all models, but such an effort MUST include domain experts for those models, i.e. likely the original modellers.

Both DatasetMetadata and [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/STC2/][STC2]] have been ported to the last VO-DML version (Spring 2016).

Many of these models have been created from a UML definition using an XSLT script available in the [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/xslt/][xslt]] sub-folder. For each model an HTML documentation file has been generated from the vo-dml/xml representation using another xslt script. These can be executed using appopriate ttargets in the ant build.xml file. This also contains a target for validating vo-dml/xml files, which is especially useful for such files written by hand.

Please read the [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/README.txt][README.txt]] for a first draft of a documentation of the structure of the vo-dml folder on volute and and hints how to use the ant build.xml script for the various XSLT scripts. This documentation will be copied on this page over time.

A group of IVOA members from SAO, HST, and JHU had a face to face meeting in February 2016 to work on the current drafts and move them towards the RFC stage. Notes from the meeting and blackboard snapshot are [[https://confluence.stsci.edu/display/MastDist/VODML+Meeting][publicly available]]

A model template [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/templates/][template]] has been made available for Modelio 3.0 has. It must be first imported in Modelio and then used as a base for the new model. Before to be converted in VO-DML, the model must be exported as an XMI (UML2.4) file. The others steps are described in [[https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/README.txt][README.txt]]. In some cases the XMI file must be patched by hand (UML namspace 1st row) to pass the VO-DML transformation. This has been tested on Lunix with Modelio 3.0 and on MacOS (El Captain) with Modelion 3.3.
---++ Notes for Proposed Recommendation

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This topic: IVOA > WebHome > IvoaDataModel > VODML
Topic revision: r6 - 2016-05-05 - OmarLaurino