Lattice%20QCD%20%20%20%20%20Data%20Grid%20Middleware:%20Meta%20Data%20Catalog%20(MDC)%20and%20Simple%20Replica%20Catalog%20(RC)%20Demo

1
Lattice QCD Data Grid MiddlewareMeta
Data Catalog (MDC) andSimple Replica Catalog
(RC)Demo

• M. Sato, for ILDG Middleware WG
• ILDG5, Dec, 03, 2004

2
Grid-of-Grids on MDC

• Clients can access multiple MDCs at different
  sites
• Directory service tells the locations of MDCs,
  which may be managed by LDAP

MDC
user
Japan
WS
server-side client, or user app
web browser
MDC
WS
UK
WS
MDC
US
MDC directory service
3
Interface for MDC (1)

• Query to ensemble query service (in Java)
• returns a set of GFNs in EnsembleQueryResults

EnsembleQueryResults doEnsembleQuery(String
queryFormat, / ALL, Xpath, SQL, /
String queryString, / string for query /
int startIndex, / the start index to be returned
/ int maxResults) / maximum to be
returned / class EnsembleQueryResults
String Status String queryFormat / same
as input / String queryString / same as
input / int totalRresults / total
number of matched ensemble / int
startIndex / same as input / int
numberOfGFNs / of GFNs returned /
String GFNs / the array of GFNs matched
/ String QueryTime / query time
(optional) /

• If queryFormt ALL, retrieve all data.
• SQL-style query may be useful and efficient

4
Interface for MDC (2)

• Query to metadata query service
• returns a set of metadata GFNs
• Almost the same to doEnsambleQuery.

MetadataQueryResults doMetadataQuery(String
queryFormat, / ALL, Xpath, SQL, /
String queryString, / string for query /
int startIndex, / the start index to be returned
/ int maxResults) / maximum to be
returned / class MetadataQueryResults
String Status String queryFormat / same
as input / String queryString / same as
input / int totalRresults / total
number of matched metadata / int
startIndex / same as input / int
numberOfGFNs / of GFNs returned /
String GFNs / the array of GFNs matched
/ String QueryTime / query time
(optional) /
5
A Use Case
query (MDC)
ensemble query service(MDC)
doEnsembleQuery
EnsembleQueryResults
get the ensemble file using GFN by RC and TRUL
GFN (RC)
RC
ensemble data
TURL for ensemble XML and the file itself
query (MDC)
metadata query service
doMetadataQuery
MetadataQueryResults
GFN (RC)
get the metadata file using GFN by RC and TURL
RC
metadata
TRUL for metadata XML and the file itself
GFN
RC
configuration data
get the configuration file using GFN and TURL
configuration (binary?)
6
Demo

• Design of MDC interface in WSDL
• Using Axis (an apache project) to generate
  interface
• A prototype implementation of WS by Axis
• Demo info page
• http//www.lqa.ccs.tsukuba.ac.jp/WS

7
Plan

• Documentation of the definitions of MDC interface
  (for single MDC)
• Finish the implementation and some command
  interface
• Multiple MDCs
• Directory service of MDCs (project info?)
• Web browser interface for Multiple MDCs