Spatial Filter in LUcene

Date	2008/11/04
Contact(s)	fxprunayre, jesse
Last edited	Timestamp
Status	draft
Assigned to release	to be determined
Resources	Resource available

Overview

Actually GeoNetwork only handle bbox search using Lucene

In a metadata record you could define an extent using

• a description
• a bbox in latlong
• or a gml object

In the search interface, we could search using a geographic keyword (matched to description in the metadata) or bbox matched to bbox in metadata

Requirements:

• handle geographic search between user search criteria (which could be description (eg. canton, commune), bbox, geomtries and metadata records extent information

Proposal Type

• Type: Index
• App: GeoNetwork
• Module: Lucene Index : LuceneSearcher (main, xml, rss, pdf search) and CatalogueSearcher (CSW search)

Links

• Documents:
• Email discussions:
• Other wiki discussions:

Voting History

• Vote proposed by X on Y, result was +/-n (m non-voting members).

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Motivations

Improve spatial search support in GeoNetwork.

Proposal

On indexing procedure, populate a spatial index based on Shapefile (stored in WEB-INF/lucene/spatial). Store the shapefile index in memory to run the spatial filter after the search.

The following operations are supported :

• ENCLOSES
• CROSSES,
• OUTSIDEOF,
• EQUAL,
• INTERSECTION,
• OVERLAPS,
• TOUCHES,
• WITHIN,

Query Examples :

• ​http://localhost:8080/geonetwork/srv/en/xml.search?geometry=POLYGON((10%2010,10%2020,20%2020,20%2015,10%2010))&relation=intersection
• ​http://localhost:8080/geonetwork/srv/en/xml.search?geometry=POLYGON((10%2010,10%2020,20%2020,20%2015,10%2010))&relation=equal
• ​http://localhost:8080/geonetwork/srv/en/xml.search?geometry=POLYGON((7%2046,7%2047,8%2047,7%2046,7%2046))&relation=equal
• ​http://localhost:8080/geonetwork/srv/en/xml.search?geometry=POINT(7%2046)

Backwards Compatibility Issues

Risks

Participants

• fxprunayre, jesse