Perhaps you want to review JSON-LD and RML to understand what the two standards are doing then suddenly your question become very obvious.
With JSON-LD, you add "extra elements" to existing JSON data to translate JSON to triples with almost no control about how should subjects, predicates and objects in the triples be generated from JSON. With RML, you specify exactly what XML/JSON elements should become whether subjects or predicates or objects. You can even specify the format of the URI to be generated etc... Have a look at the example here http://rml.io/RML_examples.html On Wed, Nov 7, 2018 at 9:41 PM Laura Morales <[email protected]> wrote: > This made me thinking... if I can convert CSV, XML, and other formats to > JSON, and then use JSON-LD context and framing to change the data to my > linking, why do tools such as RML, YARRRML, and SPARQL-Generate exist at > all? Do they do anything at all that can't be done with JSON-LD? > > > > > Sent: Monday, November 05, 2018 at 9:10 AM > From: "Christopher Johnson" <[email protected]> > To: [email protected] > Subject: Re: Loosely converting JSON/XML to RDF > Another approach is to use JSON-LD. A JSON document can be "converted" to > RDF by adding a context and using the toRDF method[1] in one of the JSON-LD > libraries. Defining the context is similar to what is done with RML, > basically mapping data objects to structured vocabulary terms. If your XML > is sufficiently denormalized, you can also convert that to JSON and repeat > the same process as above. > > Christopher Johnson > Scientific Associate > Universitätsbibliothek Leipzig > > [1] https://json-ld.org/spec/latest/json-ld-api/#object-to-rdf-conversion > > On Mon, 5 Nov 2018 at 08:55, Alex To <[email protected]> wrote: > > > We have web services returning XML and JSON in our environment. We use > > > https://github.com/RMLio/rmlmapper-java[https://github.com/RMLio/rmlmapper-java] > to map XML/JSON to RDF with > > satisfied results. > > > > Or course you need a valid URI for your XML or Json elements for e.g. in > > our XML, if we have <Student id="...">...</Student> then we use RML to > map > > it to > > > > > http://ourdomain.com/resources/students/[http://ourdomain.com/resources/students/]{id} > rdfs:type > > http://ourdomain.com/ont/Student[http://ourdomain.com/ont/Student] > > > > You can define your own URI generation scheme whatever works for you > > > > You can read more about RDF Mapping Language (RML) from W3C website. > > > > Regards > > > > On Mon, 5 Nov 2018 at 6:34 pm, Laura Morales <[email protected]> wrote: > > > > > I have a mixed set of datasets in XML, JSON, and RDF formats. I would > > like > > > to convert all the XML/JSON ones to RDF such that I can only use one > > query > > > language/library to access all the data, instead of having three > > different > > > ones. I'm also not interested in using any particular ontology or > > > vocabulary for the conversion, so anything will work as long as I can > > make > > > the conversion. > > > What would be an appropriate strategy for this? Since RDF requires > > > absolute IRIs, would it be a good idea for example to convert all > > > properties to > http://example.org/property-name-1[http://example.org/property-name-1], > > > http://example.org/property-name-2[http://example.org/property-name-2], > ...? And maybe use UUIDs for nodes? > > > Or is there a better way of doing this? > > > > > > --
