An%20HDF-EOS%20Data%20Server%20Based%20on%20OPeNDAP%20and%20ECHO

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An HDF-EOS Data ServerBased on OPeNDAP and ECHO

• Bob Bane, Mohammad Rabi, Weijun Su, Richard
  Ullman, Jingli Yang, Zhangshi Yin
• Data Usability Group, NASA/GSFC

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HDF-EOS data access via web

• Findable
• With standard search engines
• With domain-specific engines
• Browseable
• Per-granule web page
• Readable metadata
• Links for fetching data
• Retrievable
• Whole dataset
• Metadata only
• Individual fields
• Sectorized fields

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Intended Audience

• Groups that are generating HDF-EOS products
• Need a straightforward, inexpensive way to
  publish them to the web
• Major archives already have their own systems -
  this is for everyone else

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Tools used

• Standard tools
• Unix shell scripts
• Apache web server
• Earth science standards and protocols
• OPeNDAP
• ECHO
• Our tools
• ODL lt-gt XML lt-gt HTML

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OPeNDAP

• netCDF via HTTP
• Also works for HDF 4/5 and HDF-EOS 2/5
• http//opendap.org

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ECHO

• EOS ClearingHouse
• Searchable repository for earth science metadata
• Based on standard commercial tools
• Databases
• E-commerce middleware
• http//echo.eos.nasa.gov

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Our Tools

• hemu - extracts ODL metadata
• odl2xml - converts ODL to EOS-compatible XML
• heex - breaks an HDF-EOS dataset into field files
  with an HTML/XML table of contents
• XSLT stylesheets - convert XML to pretty HTML

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HDF_EOS files
OPeNDAP server
Fetch/sectorize
hemu
heex
DODS client
ODL metadata
Web server
Web browser
Field files
XML contents
Browse/fetch
odl2xml
ECHO client
Search/query
XML metadata
Search engines
Pretty HTML
XSLT
File transfer
ECHO server
ECHO XML
XSLT
Web/HTTP
Implemented by us
Other tools
Client-side services
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Installation

• Foundation
• Unix
• Apache
• Java
• Libraries
• HDF4/5, HDF-EOS2/5
• SDP Toolkit
• OPeNDAP server
• Our software
• heex, odl2xml, hemu
• heserve scripts

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Use

• Two shell scripts
• ingest granule-file.hdf
• Publishes granule to the web
• echoingest metadata.xml
• Publishes web links for granule to ECHO
• Optionally called by ingest

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Granule Web Pages
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Granule Web Pages
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Granule Web Pages
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Granule Web Pages
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(No Transcript)
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Screen shot

• Showing link dragged into DODS client

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Where is the software?

• http//hdfeos.gsfc.nasa.gov
• Tools link
• heserve system