------------------------------------------------------------------------------------------
Service Registration Rules
------------------------------------------------------------------------------------------
This file contains a copy of the parsing rules used for Service Registration.
These dictate what data will be extracted from a science metadata document, to be indexed,
if said document represents a (member node) service description.
The fields we attempt to index are:
IsService whether the document holds a service description
ServiceTitle the service's title
ServiceDescription the description of the service
ServiceType the type of service being described (ex: WMS, )
SerivceInput may refer to either an identifier for valid data for the service, or may be an input format
ServiceOutput the output format for the service
ServiceEndpoint a URL that indicates where to access the service
ServiceCoupling whether the service is 'tightly' coupled to a set of data, or is a general ('loosely' coupled) service
Note: For a more general overview of indexing implementation & design, see:
https://repository.dataone.org/documents/Projects/cicore/reference/source/search_index_config.txt
Also see:
https://repository.dataone.org/documents/Projects/cicore/architecture/MemberNodeServices/build/html/MNServices.html
https://repository.dataone.org/documents/Projects/cicore/architecture/MemberNodeServices/MemberNodeServices.pdf
The below rules should coincide with the XPath expressions in the corresponding
application-context-*-base.xml files.
--------------------------------
ISO 19119
--------------------------------
(See application-context-isotc211-base.xml)
In ISO 19119, services may be tightly or loosely-coupled to data they operate on and
sit under the srv:SV_ServiceIdentification element. Or they may be limited to
tightly-coupled distribution info and sit under the gmd:distributionInfo element.
The solr fields may be populated either with one expression checking and/or concatenating
both the srv:srv:SV_ServiceIdentification and gmd:distributionInfo locations.
(for example: isotc.isService or isotc.serviceCoupling)
Or there may be 2 separate expressions for the different scenarios
that affect the same field.
(for example: sotc.serviceEndpoint and isotc.distribServiceEndpoint)
Two expressions are only used for multivalue SolrFields; this way both results are
added - both srv:SV_ServiceIdentification and gmd:distributionInfo subelements
are indexed).
field: xpath & comments:
IsService boolean(//srv:SV_ServiceIdentification or //gmd:distributionInfo/gmd:MD_Distribution)
This checks for existence of either srv service description OR distribution "service" info.
ServiceTitle (//srv:SV_ServiceIdentification/gmd:citation/gmd:CI_Citation/gmd:title/gco:CharacterString | //gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:onLine/gmd:CI_OnlineResource/gmd:name/gco:CharacterString)/text()
This combines the srv service title with the distribution "service" info's titles.
ServiceDescription (//srv:SV_ServiceIdentification/gmd:abstract/gco:CharacterString | //gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:onLine/gmd:CI_OnlineResource/gmd:description/gco:CharacterString)/text()
This combines the srv service description with the distribution "service" info's descriptions.
ServiceType //srv:SV_ServiceIdentification/srv:serviceType/gco:LocalName/text()
//gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:onLine/gmd:CI_OnlineResource/gmd:protocol/gco:CharacterString/text()
Both are evaluated / indexed, checking the srv and distributionInfo locations for a service type.
SerivceInput //srv:SV_ServiceIdentification/srv:operatesOn/@xlink:href
//gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/@xlink:href
Both are evaluated / indexed, checking the srv and distributionInfo locations for service input.
ServiceOutput //srv:SV_ServiceIdentification/gmd:resourceFormat/@xlink:href
//gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorFormat/gmd:MD_Format/gmd:version/gco:CharacterString/text()
Both are evaluated / indexed, checking the srv and distributionInfo locations for service output.
ServiceEndpoint //srv:SV_ServiceIdentification/srv:containsOperations/srv:SV_OperationMetadata/srv:connectPoint/gmd:CI_OnlineResource/gmd:linkage/gmd:URL/text()
//gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:onLine/gmd:CI_OnlineResource/gmd:linkage/gmd:URL/text() | //gmd:distributionInfo/gmd:MD_Distribution/gmd:transferOptions/gmd:MD_DigitalTransferOptions/gmd:onLine/gmd:CI_OnlineResource/gmd:linkage/gmd:URL/text()
Both are evaluated / indexed, checking the srv and distributionInfo locations for service endpoints.
ServiceCoupling concat( substring('loose', 1 div boolean( //srv:SV_ServiceIdentification/srv:couplingType/srv:SV_CouplingType/@codeListValue = 'loose')),
substring('tight', 1 div boolean( //srv:SV_ServiceIdentification/srv:couplingType/srv:SV_CouplingType/@codeListValue = 'tight')),
substring('tight', 1 div boolean( //gmd:distributionInfo/gmd:MD_Distribution and not(//srv:SV_ServiceIdentification/srv:couplingType/srv:SV_CouplingType/@codeListValue))),
substring('', 1 div boolean( not( //srv:SV_ServiceIdentification/srv:couplingType/srv:SV_CouplingType/@codeListValue)
and not( //gmd:distributionInfo/gmd:MD_Distribution))))
The srv location can explicitly set this and if set will override distributionInfo.
The above will set:
'loose' coupling if srv:SV_CouplingType is loose
'tight' coupling if srv:SV_CouplingType is tight
'tight' coupling if distribution service info exists and srv:SV_CouplingType doesn't / is unspecified
empty if neither exists
--------------------------------
EML
--------------------------------
(See application-context-eml-base.xml)
The EML spec is rather limited in what info it can hold about services.
EML holds no elements that correspond to these fields:
ServiceType, SerivceInput, ServiceOutput, ServiceCoupling
So info about these can't be indexed.
Supported fields are below.
field: xpath & comments:
IsService boolean(//software/implementation/distribution/online/url)
Checks for the presence of a distribution url.
ServiceTitle //software/title//text()[normalize-space()]
Fetches the software title.
ServiceDescription //software/abstract//text()[normalize-space()]
Fetches the software abstract.
ServiceEndpoint //software/implementation/distribution/online/url/text()
Fetches the distribution url.