Information about RDF data

The data command can be used to parse one or more RDF data files in different formats.

Obtaining information about an RDF data file

Assuming the following content appears in a file called simple.ttl:

prefix : <http://example.org/>
prefix xsd: <http://www.w3.org/2001/XMLSchema#>

:a :name "Alice" ;
   :birthdate "1990-05-02"^^xsd:date ;
   :enrolledIn :cs101 .

:b :name "Bob", "Robert" .

:cs101 :name "Computer Science" .   

The following command parses the file simple.ttl and shows its contents:

rudof data simple.ttl

Converting between different RDF data syntaxes

It is possible to specify the output format to serialize the RDF data using the -r option. Possible values are: rdfxml, ntriples, trig, etc.:

rudof data -r rdfxml simple.ttl

The output would be something like:

<?xml version="1.0" encoding="UTF-8"?>
<rdf:RDF xmlns:="http://example.org/" 
   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
   xmlns:xsd="http://www.w3.org/2001/XMLSchema#">
        <rdf:Description rdf:about="http://example.org/cs101">
                <name>Computer Science</name>
        </rdf:Description>
        <rdf:Description rdf:about="http://example.org/b">
                <name>Bob</name>
                <name>Robert</name>
        </rdf:Description>
        <rdf:Description rdf:about="http://example.org/a">
                <enrolledIn rdf:resource="http://example.org/cs101"/>
                <birthdate rdf:datatype="http://www.w3.org/2001/XMLSchema#date">1990-05-02</birthdate>
                <name>Alice</name>
        </rdf:Description>
</rdf:RDF>

It is possible to convert RDF data to a visual representation using the options svg, png or plantuml (see RDF visualization section).

Obtaining information about an RDF data located remotely

It is also possible to get RDF data from files which are remotely available through URIs like:

rudof data https://raw.githubusercontent.com/rudof-project/rudof/refs/heads/master/examples/simple.ttl

Merging RDF data

The data command can also be used to parse more than one RDF data files, merge them and serialize them to any of the RDF formats supported.

We carse several files, merge and serialize them in any of the RDF supported formats.

rudof data user.ttl simple.ttl -r rdfxml -o output.rdf

It is possible to serialize the files using a different format, like ntriples, rdfxml, etc.

RDF visualization

It is possible to generate a visual representation of simple RDF graphs by using the --result-format option and selecting a visual format like svg or png.

The visualization is leveraged on PlantUML so it is necessary to have the PlantUML binary downloaded and available through the PLANTUML variable.

Another alternative is to use the plantuml result format to generate an intermediate file and pass that file to some PlantUML processor.

As an example, the following command generates a plantuml file:

rudof data examples/simple.ttl -r plantuml -o file.plantuml

If you have PLANT_UML available you can use directly:

rudof data examples/simple.ttl -r svg -o file.svg

RDF Config file

The parameter --config-file (-c in short form) can be used to pass a configuration file in TOML format.

The fields that it can contain are:

• base (IRI): Default base declaration to resulve relative IRIs