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Service Object Type
WMS WMS_Layer
WFS FeatureType
SOS ObservationOffering
GVS VideoFeed
A recent version of the ebRIM profile document provides more flexibility for objectType, in that it may take on a URN of the form:
urn:ogc:specification:csw-ebrim:objectType:Dataset: Here are representative URNs proposed by CubeWerx that may be considered in future
ebRIM catalog implementations: Service
Object Type WMS
urn:ogc:specification:csw-ebrim:objectType:Dataset:WMS_Layer WFS
urn:ogc:specification:csw-ebrim:objectType:Dataset:WFS_Feature
13.2.2 Association Types
A key concept of the ebRIM catalog model is the Association. Clients make use of an association to relate an extrinsic object to a service. To promote catalog interoperability,
we feel it is important to standardize a core set of association types. Here are interoperability issues we encountered in working with associations:
operatesOn vs. OperatesOn: We noted variations in the capitalization of the association name.
OperatesOn vs. HasForContents: Does an SOS OperatesOn an ObservationOffering or does it HasForContents same?
13.2.3 Case of Keywords
We believe it should be possible for a catalog to ignore case in user-specified keywords. More generally, this means allowing for the possibility of case-insensitive treatment of
the value of Literal elements in the OGC Filter expression.
13.2.4 Predicate on Spatially Restricted Searches
When specifying a geometry to bound a search, it is important for Catalog clients and services to agree on the meaning of spatial predicates. For instance, for the use case of
finding extrinsic objects that lie within a boundary of interest, is the appropriate predicate Contains or ContainedBy? After some discussion in the Common Architecture thread
Copyright © 2006 Open Geospatial Consortium – All rights reserved
57 on this specific issue, we agreed on the latter. Lesson: common understanding of the
meaning of these spatial predicates is essential to achieving interoperability.
13.2.5 Service Type
As argued previously, it is convenient to be able to locate extrinsic objects by type via the objectType attribute. One could also argue that it should be relatively easy to locate
service objects by type. The ebRIM model does not provide an attribute that might be called serviceType on service objects. However, it does provide for the use of profile-
defined slots. Although the Common Architecture thread participants agreed on the usefulness of including of a slot to define the service type, this was not actually
implemented and tested for OWS-3.
13.2.6 AccessURI Attribute in Service Binding Elements
Intergraph noted that the accessURI attribute returned on a ServiceBinding element sometimes included a query string. For example:
ebxml:ServiceBinding id=urn:uuid:836c333e-189d-459d-8571-92c883d1dde0
accessURI=http:vast.uah.edu:8080owsdopplerSos?service= SOSamp;version=0.0.31amp;request=GetCapabilities
Our understanding is that the value of accessURI should be set to what is generally referred to a prefix, that is that portion of a URI to which standard service parameters
are appended. The prefix may include a query string consisting of one or more proprietary parameters if required by a vendor.
13.2.7 Exceptions
Intergraph noted differences in the schema for the exceptions returned by the catalogs. Although this was discussed briefly during the initiative, it seems there may be some
ambiguity as to the proper schema and reported version of an exception response.
ServiceExceptionReport Example
?xml version=1.0 encoding=utf-8? ServiceExceptionReport
version=1.2.0 xmlns=http:www.opengis.netogc xmlns:xlink=http:www.w3.org1999xlink
ServiceException code=InvalidParameter Exception text...
ServiceException ServiceExceptionReport
ExceptionReport Example
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?xml version=1.0 encoding=ISO-8859-1? ows:ExceptionReport
version=0.2.3 xmlns:ows=http:www.opengeospatial.netows
ows:Exception exceptionCode=CWWRS-00002 ows:ExceptionTextException text...ows:ExceptionText
ows:Exception ows:ExceptionReport
13.3 Implementation Comments
