Repository configuration template - how it works¶

The diagram below provides an illustration of an RDF graph that describes a repository configuration:

Often, it is helpful to ensure that a repository starts with a predefined set of RDF statements - usually one or more schema graphs. This is possible by using the owlim:imports property. After start up, these files are parsed and their contents are permanently added to the repository.

In short, the configuration is an RDF graph, where the root node is of rdf:type rep:Repository, and it must be connected through the rep:RepositoryID property to a Literal that contains the human readable name of the repository. The root node must be connected via the rep:repositoryImpl property to a node that describes the configuration.

The type of the repository is defined via the rep:repositoryType property and its value must be graphdb:FreeSailRepository to allow for custom Sail implementations (such as GraphDB) to be used in RDF4J 2.0. Then, a node that specifies the Sail implementation to be instantiated must be connected through the sr:sailImpl property. To instantiate GraphDB, this last node must have a property sail:sailType with the value graphdb:FreeSail - the RDF4J framework will locate the correct SailFactory within the application classpath that will be used to instantiate the Java implementation class.

The namespaces corresponding to the prefixes used in the above paragraph are as follows:

rep:   <http://www.openrdf.org/config/repository#>
sr:    <http://www.openrdf.org/config/repository/sail#>
sail:  <http://www.openrdf.org/config/sail#>
owlim: <http://www.ontotext.com/trree/owlim#>

All properties used to specify the GraphDB configuration parameters use the owlim:prefix and the local names match up with the Configuration parameters, e.g., the value of the ruleset parameter can be specified using the http://www.ontotext.com/trree/owlim#ruleset property.