Draft Feta Interface

This is a draft proposal for the new Feta interface. (It has not been implemented).

Feta service representation

A seperate client side software is written to publish and reconstruct feta services. The software is based on the feta service schema attached.

All elements in this XML schema are mapped to existing entities in the registry's WSDL, metadata and UDDI interfaces. For each serviceDescription, a WSDL file is automatically generated to store the operations and parameters.

ServiceDescription?	UDDI businessService
serviceName	UDDI businessService name
organisation	UDDI businessEntity (see *)
author	service metadata
location URL	binding template
interface WSDL	tModel
serviceDescriptionText	UDDI businessService description
operations	WSDL operations
serviceType	service metadata

* All s in a belong to the same business Entity.

ServiceOperation?	WSDL operation
operationName	WSDL operation name
operationSpec	operation metadata
operationDescriptionText	operation metadata
operationInputs	WSDL message part
operationOutputs	WSDL message part
operationTask	operation metadata
operationResource	operation metadata
operationResourceContent	operation metadata
operationMethod	operation metadata
operationApplication	operation metadata

OrganisationType?	UDDI businessEntity
name	UDDI business name
description	UDDI business description

InterfaceType?	UDDI bindingTemplate
name	binding metadata
description	binding description
locationURI	binding access point
operation	tModelInstanceDetails -> tModelKeys

ParameterType?	WSDL message part
name	message part name
transportDataType	message part type
description	message part metadata
semanticType	message part metadata
isConfigurationParameter	message part metadata
formats	message part metadata

service publication

save_service

This will be in the format of

<save_service serviceKey="">
    <fetaServiceDecription/>
</save_service>

Returns a serviceDetail with an assigned fetaServiceKey on success. If a serviceKey is supplied and already exist in grimoires, it will replace the existing entry. This can be used to update an existing fetaService.

delete_service

<delete_service>
    <fetaServiceKey>.....</fetaServiceKey>
</delete_service>

queries

find_service

This operation searches for a list of services matching certain specified criteria. Composite search is achieved by using more than one elements. The elements defined are those supplied by Pinar.

<complextType name="find_service">
  <sequence>
    <element name="input" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="output" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="task" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="resource" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="method" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="application" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="name" type="string" minOccurs="0" maxOccurs="unbounded">
    <element name="description" type="string" minOccurs="0" maxOccurs="unbounded">
  </sequence>
</find_service>

The query returns the hasServiceNameText and hasOperationNameText in the feta service. We could do something similar:

<serviceList>
   <fetaService><serviceName/><operationName/></fetaService>
   <fetaService/>
</serviceList>

We already have the RDQLs for query by application, input, output, method, resource and task.

get_serviceDetail

Returns a feta service with a given fetaServiceKey

get_allServices

Returns a list of all feta service registered. This is equivalent to GetAll^?.

Ontology publication

A new Inference Model will need to be added to grimoires for RDFS type reasoning. This is how we could set it up in Jena:

   Model GrimoiresTripleStore;
   Model FetaOntology;
   InfModel InferenceModel = new InfModel(FetaOntology, GrimoiresTripleStore);

Triples added from the existing interfaces and feta services will be stored in the GrimoiresTripleStore^? model. The FetaOntology^? Model is for storing feta ontology files. Queries from the feta interface is done via the InferenceModel^?, all queries in other interfaces are done via the GrimoiresTripleStore^? Model. This means reasoning is not turned on in other interfaces.

Every time a new triple is added to GrimoiresTripleStore^?, we need to call InfModel^?::rebind() to reconsult the underlying data. I believe we only need to do the rebind only for publishing in the feta interface.

Changes in the ontology model is not re-read with a rebind(). A new InfModel^? has to be created.

If we decide to store feta data in a separate Model (say FetaTripleStore^?), and want the Model's data to be available to other interfaces, then a union operation of GrimoiresTripleStore^? and FetaTripleStore^? is needed whenever either model is updated. (We assume there will be more inquiries than publications).

add_ontology

<add_ontology>
   <url>http://example.com/example.rdfs</url>
</add_ontology>

remove_ontologies

Either or both:

1. Clears all statements in the feta ontology model.
2. Supply a URL of the ontology to remove. The ontology file must still exist as this operation involves removing triples contained in the file.

General metadata

The requirments document mentions the annotation of metadata to feta services. This can be achieved using grimoires metadata interface by adding a new entityReference type for it. Proposed entityType is http://www.mygrid.org.uk/feta#fetaServiceKey. (We may use the namespace we give for the feta.wsdl).

Client libraries and testing

We would provide the Java classes created by WSDL2Java as the client library. This should allow feta to call the new interface directly within Java. As such, I'd suggest writing junit tests using the Java classes as well.

-- SylviaWong - 22 Feb 2005
direct publication of feta services, ontology, general metadata, testing
-- SylviaWong - 23 Feb 2005
representation of feta services
-- SylviaWong - 24 Feb 2005 more ontology stuff
-- SylviaWong - 20 Apr 2005 feta XML schema and how it's mapped to grimoire's existing entities.

• common.xsd: feta service description XML schema v1.4 2005/07/10

to top