patrick.dowler at nrc-cnrc.gc.ca
Fri Sep 10 12:34:07 PDT 2010
Now that summer is over I want to get some discussions going and make some
progress in the DAL-WG. I encourage everyone with an interest in defining and
implementing data access *and* in writing applications that use the data
access services to contribute. Although we will have most of the discussions
on this mailing list, I am looking into the plausibility of having some more
specific discussions via telecon in order to make progress in key areas.
* Where are we now?
The Standing Committee on Science Priorities has outlined a few high priority
science cases that we as a community need to tackle.
First, the ObsTAP project is nearing completion. This is mainly a DM-WG
project (ObsCore DM) but for use in a TAP service we need to define an
extension schema so TAP services can advertise that they support this (and
other) data models.
The next priority is to deliver services to support the SED science cases.
This has already been identified to require the photometry data model (PhotDM)
and is closely related to SSA; in the coming months we will need to study the
science cases and determine what is required in DAL to expose this model and
support the use cases.
The final science use case that impacts DAL is for users to be able to search
by list of sources and types of sources; this sounds like functionality that
is available via TAP but likely requires wider implementation, additional
content, and orchestrated use of multiple services.
We currently have several standards under development or being considered for
update. Inconsistencies have been identified in SpecDM that require an update
to the model and may require an update to the SSA specification. We also have
several ongoing efforts that have been languishing (PQL, SIAv2), transfers from
other groups (SimDAP), and several new proposals (simple event access, simple
light curve access).
* priorities for DAL
- TAP (or DAL) extension schema
- possible SSA maintainence release (1.x?) when SpecDM changes are known
- new SSA (1.x or v2?) to support the SED science case
- understanding new ideas/proposals and where they fit in
There is not much to discuss here unless I inadvertently left something out.
In a follow-up message, I will present a modest proposal for a roadmap of DAL
activities (relatively short-term), which I am sure will prompt some
Once we have defined the various parts, I will re-organise the DAL-WG wiki
pages to make them a useful point of coordination.
Tel/Tél: (250) 363-0044
Canadian Astronomy Data Centre
National Research Council Canada
5071 West Saanich Road
Victoria, BC V9E 2M7
Centre canadien de donnees astronomiques
Conseil national de recherches Canada
5071, chemin West Saanich
Victoria (C.-B.) V9E 2M7
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