VOResource Extensions for Describing SSA, SIA, SLA, and ConeSearch Services

Note:

This standard SimpleDALRegExt is formerly known as RegSimpleDAL; discussion of the standard has moved here.

The page tracks the development of the IVOA specification document defining VOResource Extensions for SSA, SIA, SLA, and ConeSearch Services. The draft abstract is as follows:

An application that queries or consumes descriptions of VO resources must be able to recognize a resource's support for standard IVOA protocols. This specification describes how to describe a services that supports four fundemental data access protocols--Simple Cone Search (SCS), Simple Image Access (SIA), Simple Spectral Access (SSA), Simple Line Access (SLA)--using the VOResource XML encoding standard. A key part of this specification is the set of VOResource XML extension schemas that define new metadata that are specific to those protocols. This document describes in particular rules for describing such services within the context of IVOA Registries and data discovery as well as the VO Stadard Interface (VOSI) and service self-description. In particular, this document spells out the essential mark-up needed to identify support for a standard protocol and the base URL required to access the interface that supports that protocol.

Contents

Documents

Proposed Recommendation

Describing Simple Data Access Services v1.0 -- 20120517

• The RFC is closed; a new version will be posted soon for TCG review

Internal PR Revision

Describing Simple Data Access Services v1.0 -- 20121026 (upload to repository pending)

• This PDF is formatted for a TOC w/ page numbers and nicer page breaks.
• This abbreviated PDF does not include the appendix listing the full XML Schemas for 50% fewer pages.

Internal PR Schemas (upload to repository pending)

ConeSearch-v1.0pr4.xsd
SIA-v1.0pr3.xsd
SSA-v1.0pr2.xsd
SLAP-v1.0pr2.xsd

Working Draft Schemas

ConeSearch-v1.0.xsd
SIA-v1.0.xsd
SSA-v1.0.xsd
SLAP-v0.1.xsd

Samples

• conesearch.xml
• sia.xml
• ssa.xml
• sia2ver.xml -- illustrates how to describe simultaneous support for 2 different versions of SIA.
• sla.xml

Status

• SimpleDALRegExt is currently in RFC Review period: May 23, 2012 - June 27, 2012
• Two major changes were incorporated into the latest draft as a result of the Oct 2011 Interop:
  • recommended prefix changed from ssa to ssap
  • re-added <supportedFrame>
  The details can be reviewed in this follow-up report
• The volute google code repository is being used to manage the internal versions of the documents and samples. You can find them under trunk/projects/registry/SimpleDALRegExt

-- GretchenGreene - August 3, 2012

Schema-to-Spec Stylesheet

To support this effort, a few people (Harrison, Plante) have author XSL stylesheets to convert XML Schemas into HTML. Ray Plante's efforts have been uploaded to the volute google code repository under trunk/projects/registry/tools. more info coming

Comments to current draft

The suggested ssa: prefix for the SSAP extension schema is unfortunate. This is due to the abuse of xmlns in "binding" the model name (the thing before the colon in a utype) to a data model URL in the SSA spec. Withit, in any document that contains SSA utypes (e.g., table definitions of SSA services), the ssa XML prefix is taken. So -- can we use ssap? Or ssareg?

-- MarkusDemleitner - 18 May 2011

The suggestion was incorporated into the latest draft.

-- RayPlante

Historical materials

This work used to be traced via the RegSimpleDAL page. That page is now deprecated. Attachments to that page include:

• RegSimpleDAL-wd.html