fcrepo-event-ontology

An ontology for describing Fedora events.

Namespace

The Fedora event ontology namespace is http://fedora.info/definitions/v4/event#.

Classes

Each event will be described with one or more rdf:type values from the Fedora event ontology. These types include:

• event:ResourceCreation
• event:ResourceDeletion
• event:ResourceModification
• event:ResourceRelocation

Application profile for Fedora events (proof-of-concept)

This ontology is only one part of a larger application profile for describing Fedora events. That application profile is still a work in progress and is dependent on a finalization of the Fedora Messaging SPI specification.

Data described in events

According to the draft Fedora SPI specification, each event must contain the following data:

• The URL of the affected resource
• The dateTime of the resource modification
• The rdf:type of the affected resource
• A unique identifier for the event
• The type of repository event (e.g. event:ResourceModification)

In addition, these properties are optional:

• The location of the repository (e.g. the root of the repository)
• The resource path (i.e. the URL with the repository root removed)
• The user(s) on whose behalf the resource was changed
• The software agent(s) used to modify the resource

Using PROV to describe events

In this proof of concept, Fedora events are described using the PROV ontology along with some other commonly used ontologies (foaf, dcterms).

RDF structure (TTL)

A message could be described in RDF like so:

@prefix prov: <http://www.w3.org/ns/prov#> .
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix event: <http://fedora.info/definitions/v4/event#> .
@prefix fedora: <http://fedora.info/definitions/v4/repository#> .
@prefix ex: <http://example.org/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<http://localhost:8080/fcrepo/rest/path/to/resource> a ex:CustomType,
      fedora:Container, fedora:Resource, prov:Entity;
  prov:wasAttributedTo [ a prov:Person; foaf:name "fedo raAdmin"],
      [ a prov:SoftwareAgent; foaf:name "CLAW client/1.0"];
  prov:wasGeneratedBy [
      a event:ResourceCreation, prov:Activity;
      prov:atTime "2016-05-19T17:17:39-04:00Z"^^xsd:dateTime;
      dcterms:identifier <urn:uuid:3c834a8f-5638-4412-aa4b-35ea80416a18> ];
  dcterms:isPartOf <http://localhost:8080/fcrepo/rest> .

Example Event (JSON-LD)

In a messaging system, it would be more common that a message would be serialized as compact JSON-LD. A compact JSON-LD serialization could, therefore, take the following form:

{
  "@context" : "http://fedora.info/definitions/v4/event.json" ,
  "id" : "http://localhost:8080/fcrepo/rest/path/to/resource" ,
  "type" : [
    "http://www.w3.org/ns/prov#Entity" ,
    "http://fedora.info/definitions/v4/repository#Resource" ,
    "http://fedora.info/definitions/v4/repository#Container" ,
    "http://example.org/CustomType" ] ,
  "isPartOf" : "http://localhost:8080/fcrepo/rest" ,
  "wasGeneratedBy" : {
    "type" : [
      "http://www.w3.org/ns/prov#Activity" ,
      "http://fedora.info/definitions/v4/event#ResourceCreation" ] ,
    "identifier" : "urn:uuid:3c834a8f-5638-4412-aa4b-35ea80416a18" ,
    "atTime" : "2016-05-19T17:17:39-04:00Z" } ,
  "wasAttributedTo" : [
    { "type" : "http://www.w3.org/ns/prov#Person" ,
      "name" : "fedo raAdmin" },
    { "type" : "http://www.w3.org/ns/prov#SoftwareAgent" ,
      "name" : "CLAW client/1.0" } ]
}

Or, with the @context included inline:

{
  "@context" : {
    "xsd" : "http://www.w3.org/2001/XMLSchema#" ,
    "type" : "@type" ,
    "id" : "@id" ,

    "atTime" : { "@id" : "http://www.w3.org/ns/prov#atTime", "@type" : "xsd:dateTime" } ,
    "identifier" : { "@id" : "http://purl.org/dc/terms/identifier" , "@type" : "@id" } ,
    "isPartOf" : { "@id" : "http://purl.org/dc/terms/isPartOf", "@type" : "@id" } ,
    "name" : { "@id" : "http://xmlns.com/foaf/0.1/name" } ,
    "wasAttributedTo" : { "@id" : "http://www.w3.org/ns/prov#wasAttributedTo", "@type" : "@id" } ,
    "wasGeneratedBy" : { "@id" : "http://www.w3.org/ns/prov#wasGeneratedBy", "@type" : "@id" }
  } ,

  "id" : "http://localhost:8080/fcrepo/rest/path/to/resource" ,
  "type" : [
    "http://www.w3.org/ns/prov#Entity" ,
    "http://fedora.info/definitions/v4/repository#Resource" ,
    "http://fedora.info/definitions/v4/repository#Container" ,
    "http://example.org/CustomType" ] ,
  "isPartOf" : "http://localhost:8080/fcrepo/rest" ,
  "wasGeneratedBy" : {
    "type" : [
      "http://www.w3.org/ns/prov#Activity" ,
      "http://fedora.info/definitions/v4/event#ResourceCreation" ] ,
    "identifier" : "urn:uuid:3c834a8f-5638-4412-aa4b-35ea80416a18" ,
    "atTime" : "2016-05-19T17:17:39-04:00Z" } ,
  "wasAttributedTo" : [
    { "type" : "http://www.w3.org/ns/prov#Person" ,
      "name" : "fedo raAdmin" },
    { "type" : "http://www.w3.org/ns/prov#SoftwareAgent" ,
      "name" : "CLAW client/1.0" } ]
}