HR: 10:50h
AN: IN32A-03 [Abstracts]
TI: The Live Access Server - A Web-Services Framework for Earth Science Data
AU: * Schweitzer, R
EM: Roland.Schweitzer@noaa.gov
AF: Weathertop Consulting, LLC, 2802 Cimarron Ct., College Station, TX 77845
United States
AU: Hankin, S C
EM: Steven.C.Hankin@noaa.gov
AF: Pacific Marine Environmental Laboratory, NOAA R/PMEL
7600 Sand Point Way N.E., Seattle, WA 98115
United States
AU: Callahan, J S
EM: Jonathan.S.Callahan@noaa.gov
AF: Joint Institute for the Study of the Atmosphere and Ocean, Lisa Li Building
4909 25th Ave NE
University of Washington, Box 354235, Seattle, WA 98195
AU: O'Brien, K
EM: Kevin.M.O'Brien
AF: Joint Institute for the Study of the Atmosphere and Ocean, Lisa Li Building
4909 25th Ave NE
University of Washington, Box 354235, Seattle, WA 98195
AU: Manke, A
EM: Ansley.B.Manke@noaa.gov
AF: Pacific Marine Environmental Laboratory, NOAA R/PMEL
7600 Sand Point Way N.E., Seattle, WA 98115
United States
AU: Wang, X Y
EM: Xiaoping.Y.Wang@noaa.gov
AF: Joint Institute for the Study of the Atmosphere and Ocean, Lisa Li Building
4909 25th Ave NE
University of Washington, Box 354235, Seattle, WA 98195
AB:
The Live Access Server (LAS) is a general purpose Web-server for delivering services related to geo-science data sets. Data
providers can use the LAS architecture to build custom Web interfaces to their scientific data. Users and client programs
can then access the LAS site to search the provider's on-line data holdings, make plots of data, create sub-sets in a variety
of formats, compare data sets and perform analysis on the data.
The Live Access server software has continued to evolve by expanding the types of data (in-situ observations and curvilinear
grids) it can serve and by taking advantages of advances in software infrastructure both in the earth sciences community
(THREDDS, the GrADS Data Server, the Anagram framework and Java netCDF 2.2) and in the Web community (Java Servlet and the
Apache Jakarta frameworks). This presentation will explore the continued evolution of the LAS architecture towards a
complete Web-services-based framework. Additionally, we will discuss the redesign and modernization of some of the support
tools available to LAS installers.
Soon after the initial implementation, the LAS architecture was redesigned to separate the components that are responsible
for the user interaction (the User Interface Server) from the components that are responsible for interacting with the data
and producing the output requested by the user (the Product Server). During this redesign, we changed the implementation of
the User Interface Server from CGI and JavaScript to the Java Servlet specification using Apache Jakarta Velocity backed by a
database store for holding the user interface widget components. The User Interface server is now quite flexible and highly
configurable because we modernized the components used for the implementation.
Meanwhile, the implementation of the Product Server has remained a Perl CGI-based system. Clearly, the time has come to
modernize this part of the LAS architecture. Before undertaking such a modernization it is important to understand what we
hope to gain. Specifically we would like to make it even easier to add new output products into our core system based on the
Ferret analysis and visualization package. By carefully factoring the tasks needed to create a product we will be able to
create new products simply by adding a description of the product into the configuration and by writing the Ferret script
needed to create the product. No code will need to be added to the Product Server to bring the new product on-line. The new
architecture should be faster at extracting and processing configuration information needed to address each request.
Finally, the new Product Server architecture should make it even easier to pass specialized configuration information to the
Product Server to deal with unanticipated special data structures or processing requirements.
DE: 1225 Global change from geodesy (1222, 1622, 1630, 1641, 1645, 4556)
DE: 1600 GLOBAL CHANGE
DE: 9800 GENERAL OR MISCELLANEOUS
DE: 9820 Techniques applicable in three or more fields
SC: Earth and Space Science Informatics [IN]
MN: Fall Meeting 2005