Gregory Mantelet (Observatoire astronomique de Strasbourg,CDS), Wenger M. (Observatoire astronomique de Strasbourg,CDS), Michel L. (Observatoire astronomique de Strasbourg)
We are currently implementing in the Simbad service the Table Access Protocol (TAP),
a standard of the Virtual Observatory defining a protocol for accessing astronomical
catalogs and database tables using queries written in ADQL (Astronomical Data Query Language,
another VO standard).
Implementing TAP requires several steps: the definition of a database schema with the
data the users will be able to query, the translation of ADQL queries into regular
SQL language performing the queries in Simbad, and the implementation of the UWS
(Universal Worker Service) standard to manage asynchronous queries, useful for long queries,
either through their duration or their output size.
These standards were implemented as much as possible in a generic way, allowing them to be
reused in other services, as it has already been done in the database generator SAADA.
The ADQL to SQL translator uses callbacks to implement the specific routines for a given
service. UWS has been implemented as an autonomous package, easy to reuse with very few
specific developments. The whole development is in the Java language.
The poster will show the technologies used to implement the TAP protocol, the difficulties
encountered and their solutions, and the current state of the interface, which should be
made available by the end of this year.
Poster in PDF format
Paper ID: P090