arne-bdt commented on issue #2473: URL: https://github.com/apache/jena/issues/2473#issuecomment-2118306695
I think it is fair to say: All occurrences of the bare `parseType="Statements"` are due to sloppy implementations or copy-and-paste errors. The namespace should always be `rdf:parseType="Statements"`. Google discovered an old draft of the IEC standard [Part 5xx: CIM XML Model Exchange Format](https://cimug.ucaiug.org/WG13/Part%20552%20CIM%20XML%20Model%20Exchange%20Format%20[Martin%20Miller]/Edition%201/57_1262e_CDV.pdf) . For example, on page 21, the RDF example lacks the namespace, but the text explicitly mentions the correct namespace. > Just for clarification with the namespace “dm” new statements are introduced that are valid extensions to the standard RDF syntax through the new property rdf:parseType, which is called Statements. <property parseType=”Statements”> <!-- Content: (definition|description)* --> </property> The content model of an element with rdf:parseType=”Statements” is the same as the content model of the rdf:RDF element. Today I also discovered the [RDF Syntax User Guide](https://eepublicdownloads.entsoe.eu/clean-documents/CIM_documents/Grid_Model_CIM/RDF-SyntaxUserGuide_v1-0.pdf) listed on https://www.entsoe.eu/data/cim/cim-for-grid-models-exchange/, which contains a chapter "General differences between CIM XML (552) and RDF XML (W3C)". This chapter explains a lot right at the beginning: > The CIM XML is defined in the IEC 61970-552:2016. This version of the standard is based on a much earlier edition in which some serialization assumptions were made. Important: When the initial version of IEC 61970-552 was developed, the W3C recommendations on RDF XML were not released. Therefore, there was a growing gap during the last two decades. The latest RDF XML was standardized by W3C in 2014 (RDF 1.1 XML Syntax (w3.org)) and IEC 61970-552 did not align with this due to existing implementations objecting changes in CIM XML. It lists many of the issues I've stumbled upon over the last few years. Unfortunately, the rdf:parseType="Statements" issue is missing from this chapter. There, I also found the latest [Metadata and Document Header Data Exchange Specification](https://www.entsoe.eu/Documents/CIM_documents/Grid_Model_CIM/MetadataAndHeaderDataExchangeSpecification_v2.3.0.pdf), which includes parts of the Difference Model Specification: > The content [of the DifferenceModel] is described by the Model class, the association role forwardDifferences and association role reverseDifferences. Both association roles may have one set of Statements. [chapter "7.3 (dm) DifferenceModel", page 33] Description for "forwardDifferences": > A property of the difference model whose value is a collection of statements (i.e., resources of type rdf:Statement) representing the forward difference statements. With Jena, I would want to be able to parse the forwardDifferences and backwardDifferences into separate graphs, so that I can apply them as additions and deletions, or use them in a `org.apache.jena.graph.compose.Delta`. Here is sample code to illustrate a way to read the forwardDifferences as a graph: ``` String xml = "<rdf:RDF \n" + " xml:base=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:dm=\"http://iec.ch/2002/schema/CIM_difference_model#\"; \n" + " xmlns:md=\"http://iec.ch/TC57/61970-552/ModelDescription/1#\"\n"; + " xmlns:cim=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:meta=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\";>\n" + "<dm:DifferenceModel rdf:about=\"#_248c809d-1d7b-397c-830f-6928007ae6d9\"> \n" + "<md:Model.version>1715589426</md:Model.version>\n" + "<md:Model.created>2024-05-13T08:37:06.830Z</md:Model.created>\n" + "<md:Model.scenarioTime>2024-05-13T08:37:06.830Z</md:Model.scenarioTime>\n" + "<md:Model.profile>http://profile/</md:Model.profile>\n" + "<md:Model.modelingAuthoritySet>unknown</md:Model.modelingAuthoritySet>\n" + "<meta:Model.modelVersionIri>http://ontology.adms.ru/UIP/md/2021-1</meta:Model.modelVersionIri>\n" + "<meta:Model.differenceFrom>2024-04-01T07:55:06.779475Z</meta:Model.differenceFrom>\n" + "<meta:Model.differenceTo>2027-10-01T08:37:06.779475Z</meta:Model.differenceTo>\n" + "<dm:forwardDifferences rdf:parseType=\"Statements\">\n" + "<cim:A rdf:about=\"#_individual-A-1\">\n" + "<cim:A-2-B rdf:resource=\"#_individual-B-1\"/>\n" + "</cim:A>\n" + "<cim:B rdf:about=\"#_individual-B-1\"/>\n" + "<cim:D rdf:about=\"#_individual-D-1\"/>\n" + "</dm:forwardDifferences>\n" + "<dm:reverseDifferences parseType=\"Statements\">\n" + "</dm:reverseDifferences>\n" + "</dm:DifferenceModel>\n" + "</rdf:RDF> "; Model res = ModelFactory.createDefaultModel(); RDFParserBuilder .create() .fromString(xml) .forceLang(Lang.RDFXML) .build() .parse(res); RDFDataMgr.write(System.out, res, RDFFormat.JSONLD11_PRETTY); var subjDiffModel = NodeFactory.createURI("http://iec.ch/TC57/2014/CIM-schema-cim16#_248c809d-1d7b-397c-830f-6928007ae6d9";); var predForwardDifferences = NodeFactory.createURI("http://iec.ch/2002/schema/CIM_difference_model#forwardDifferences";); //get the forward differences var objForwardDifferences = res.getGraph().find(subjDiffModel, predForwardDifferences, Node.ANY).next().getObject(); //create a new RDF/XML graph var forwardRDF = "<rdf:RDF \n" + " xml:base=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:dm=\"http://iec.ch/2002/schema/CIM_difference_model#\"; \n" + " xmlns:md=\"http://iec.ch/TC57/61970-552/ModelDescription/1#\"\n"; + " xmlns:cim=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:meta=\"http://iec.ch/TC57/2014/CIM-schema-cim16#\"\n"; + " xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\";>\n" + objForwardDifferences.getLiteralLexicalForm() + "</rdf:RDF>"; var forwardGraph = GraphFactory.createGraphMem(); forwardGraph.getPrefixMapping().setNsPrefixes(res.getNsPrefixMap()); RDFParserBuilder .create() .fromString(forwardRDF) .forceLang(Lang.RDFXML) .build() .parse(forwardGraph); RDFDataMgr.write(System.out, forwardGraph, RDFFormat.JSONLD11_PRETTY); ``` This process is not pretty, and writing DifferenceModels might even be uglier. Accepting `rdf:parseType="Statements"` seems to be a good compromise to ensure that Jena is regarded as a stable component in any CIM/XML tool chain. ### Next Steps ? I would like to approach ENTSO-E so that they may extend their chapter "General differences between CIM XML (552) and RDF XML (W3C)." Proposing the use of rdf:parseType="Literal" to improve general compatibility with RDF/XML could be one suggestion. However, does anyone have a good idea on how to express DifferenceModels with nested graphs for forwardDifferences and backwardDifferences in RDF/XML? (My knowledge of the standards and parsers is not sufficient to devise a practical solution.) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. 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