Defining RDF Classes in the Framework¶

After deciding what rdf:Classes that you will be using in the application it is now time to start specifying your classes in a RDF turtle formated file.

Steps¶

Open a text editor and add your turtle prefixes for the namespaces that you will be using:

# Required namespaces
@prefix acl: <http://www.w3.org/ns/auth/acl#> .
@prefix kds: <http://knowledgelinks.io/ns/data-structures/> .
@prefix kdr: <http://knowledgelinks.io/ns/data-resources/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

# Any addtional namespaces
@prefix schema: <https://schema.org/> .

Next add the basic information about the first class:

schema:Person a rdf:Class;
    rdfs:label "Person";
    rdfs:comment "A person (alive, dead, undead, or fictional).".

Tag the class with kds:ControlledClass. This tells the Framework what are the classes in the application:
```
schema:Person a kds:ControlledClass .
```
Now specify how the class instance data should be stored. Options are “object” or “blanknode”. This tells the Framework whether to create a new URI or store it as the blanknode in the object position of a triple:
```
schema:Person kds:storageType "object" .
```
Next determine if there is a Primary Key for the class. The Primary Key tells the framework that when adding a new instance of the class to the database that the specified properties must be unique or some combination of the properties must be unique:
```
schema:Person kds:primaryKey schema:email.
```

Note

Make the primary key a combination of properties like this:

schema:Person kds:primaryKey [
    kds:keyCombo schema:givenName;
    kds:keyCombo schema:familyName
] .

Lastly we need to define the security rules for the class:

schema:Person kds:classSecurity [
            acl:agent kdr:Admin-SG;
            acl:mode acl:Read, acl:Write
] ;

This means that anyone in the kds:Admin-SG has read and write privileges to the class.

Note

To add more permissions repeat the above information.

Putting it all together would look like this:

schema:Person a rdf:Class;
    rdfs:label "Person";
    rdfs:comment "A person (alive, dead, undead, or fictional).";
    a kds:ControlledClass ;
    kds:storageType "object" ;
    kds:primaryKey schema:email;
    kds:classSecurity [
                    acl:agent kdr:Admin-SG;
                    acl:mode acl:Read, acl:Write
    ] ;
    kds:classSecurity [
                    acl:agent kdr:LoggedIn-SG;
                    acl:mode acl:Read
    ] .

Next define your rdf:Properties!