2008 NVO Summer School1 Finding Services in the NVO Registry Gretchen Greene T HE US N ATIONAL V IRTUAL O BSERVATORY

Session Topics The first part of this session will be a demonstration and follow-along using the new NVO registry web portal The second part of the session will be a hands on exercise for following some basic java and python client interfaces to the progammatic registry services 2008 NVO Summer School2

3 Registry Web Portal Operational NVO Registry is changing functionality to adopt a new standard IVOA schema model –IVOA Registry Working Group –1.0 VO Resource schema model The Registry web portal is a major component to the NVO Search Portal We will be working with the following public web portal URL – NVO Home page reflects an earlier prototype. It will remain in operation yet soon to be phased out as the primary registry

2008 NVO Summer School4 Out with the old….

In with the New… NVO Summer School5

Registry Portal Search Keyword Search input –Space separated text input Example 1: binary star Example 2: galex Example 3: HEASARC –The default combination of entered keywords is boolean AND (OR future enhancement) Full text database index –Scans through all the standard VO Resource metadata for a contains string match Newly published resources may not appear immediately (~ 15 min delay) Will not perform direct Spatial query or source name resolution (See NVO Search Portal) 2008 NVO Summer School6

Registry Advanced Search Advanced – very basic search interface that allows sql like predicate query –Allows more refined search criterion –Search for service specific, capability, resources –Current limitation: partial ADQL implementation and full compliance will be in the future See link for metadata tags available 2008 NVO Summer School7

Search Results Table Keyword search results Tabular View –Reformats VO Resource metadata into VOTable representation –Subset of full resource metadata in this view Tabular information is arranged in a javascript filterable and sortable format –Consistent with NVO Search Portal application views and is based on a shared library STScI HLA VOView available via NVO Trac SVN Table columns may be changed using the column control list at the bottom of the page Each Row represents a single Resource 2008 NVO Summer School8

Table Filtering and Sorting Filtering allows wildcard (*) for partial matching Examples using the keyword galex –Example: *hubble* on title column –Example: *gr1* on shortname –Example: *skynode* on identifier column The filter or sort is applied to the full table, not the page only view Columns can be sorted before or after the filtering 2008 NVO Summer School9

Service Metadata Service Capabilities are mapped into user friendly service category descriptions: –Images, catalog, spectra, http request, web page, custom, … –Correspond to VO DAL protocols –Note the original NVO registry contains jargon in VO standard service terms e.g. simple image access, SIAP, SSAP, skynode, tabularskyservice…. Resources may be COMPOSITES of multiple service types 2008 NVO Summer School10

Service Categories Category column represents a generic service type definition –Catalog: Cone Search –Images: Simple Image Access Protocol (SIAP) –Spectra: Simple Spectral Access Protocol (SSAP) Additional types of Resource interfaces available: –includes NON STANDARD VO services –Web page, http request, CEA (Astrogrid Workflow), Custom… 2008 NVO Summer School11

Service Portal Data Access Catalogs and Images are accessible through a link to Simple Data Query –Search Me link appears under Browse/Query column All service types provide interface access URL which are listed in the column accessURL –Invocation requires a priori knowledge of standard protocol implementation 2008 NVO Summer School12

Full Resource Metadata Click on Full Resource link for a row in the Search results table Stylized version of the complete set of metadata is viewable under Full Record Service data access also available through the Search Me link –under the section on Service Interfaces The complete VO Resource XML instance can be viewed by clicking on the View XML link –Need to have associated app for xml viewing 2008 NVO Summer School13

Results Save or Send Features The keyword search results can be downloaded and saved to the desktop in various formats. For direct exchange between the Registry search results and other VO Portal Applications, you can Send Results to VIM, Datascope or Inventory –Automatically will transfer result table resources to these web applications 2008 NVO Summer School14

Developers - Registry Clients The registry has 3 sets of web service programmatic interfaces that are based on –IVOA standard Registry Interface –NVO Registry Portal service interfaces –IVOA Registry Open Archives Initiatives (OAI) harvesting service NVO Summer School15

Registry Interface 1.0 A standard IVOA SOAP WSDL defines a set of functions for accessing and querying registry resources –W3C web service protocol Client applications can develop code which is independent of IVOA registry implementation –To interface with a fully searchable registry Contains harvested resources from all RofR publishing registries Additional reference documentation located on the IVOA TWiki site or NVO Book – Registry Client 2008 NVO Summer School16

NVOSS Registry Client Software NVOSS software library contains sample sets for developing registry client software –JAVA version for IVOA Standard Search Interface: NVOSS_HOME/java/src/ivoaregistry –Python version for IVOA Standard Search Interface and NVO Search Portal service interface: NVOSS_HOME/python/src/registryClient 2008 NVO Summer School17

Getting Started Click on the link for this session program for Client EXERCISE NVO Summer School18