Extended Regions

Date	2012/09/14
Contact(s)	​Jesse Eichar
Last edited
Status	Proposed
Assigned to release	2.9.x
Resources	Jesse personal time
Code	​https://github.com/jesseeichar/core-geonetwork/tree/improvement/regions

Overview

This proposal intends to extend the existing Regions API with the following features:

• Add category for each region so they can be displayed in categories (for example continent, country, province)
• Add API for searching regions based:
  • name
  • category
  • bbox
• Add optional geometry for each region (in addition to bbox)
• integrate into XmlSearch and Csw so that the region id can be used to look up the geometry of the region for a spatial filter
• Add a configurable strategy object for that allows the region implementation to be easily pluggable. For example it might be based on a table in the database or wfs

Proposal Type

• Type: Improvement
• App: Geonetwork
• Module: Web

Links

• Email discussions:
• IRC discussions:
• Related work:

Voting History

• None as yet

---

Proposal

The Regions will be backwards compatible but will simply extend the functionality. Currently the Regions API provides a list of regions, each with a unique id. Each region has translated labels and a bounding box. The proposal will extend that API. The new API will be:

• Get
  • Params
    • id - required
  • Example Response:

    <response>
      <record>
        <id>338</id>
        <north>38.2</north>
        <south>-34.6</south>
        <west>-17.3</west>
        <east>51.1</east>
        <label>
          <eng>Africa</eng>
          <fre>Afrique</fre>
          <ger>Afrika</ger>
          <spa>Africa</spa>
          <rus>Africa</rus>
          <por>Africa</por>
          <chi>Africa</chi>
          <dut>Afrika</dut>
          <nor>Africa</nor>
          <fin>Africa</fin>
          <ara>Africa</ara>
          <ita>Africa</ita>
        </label>
        <category>continent</category>
        <hasGeom>false</hasGeom>
      </record>
    </response>
    

• List
  • Params
    • category - optional
    • bbox (minx,maxx,miny,maxy, srs) - optional. SRS is optional and assumed to be EPSG:4326
    • label - searches the labels for regions that contain the text in this parameters - optional
  • Example Response

    <regions count="1">
      <region>
        <id>country.1</id>
        <label>
          <eng>France</eng>
        </label>
      </region>
    </regions>
    

• GetGeom - will return the geometry for the region. If the geometry does not have a geometry then the bbox will be used to construct a polygon.
  • Params
    • id - required (if multiple are provided then multiple geometries will be returned)
    • simplified - optional (if present and true then the geometry will be a simplified version. Some implementations may ignore this hint and return full geometry)
  • Example Response:

    <response>
      <geom id="2"> MULTIPOLYGON (((30 20, 10 40, 45 40, 30 20)), ((15 5, 40 10, 10 20, 5 10, 15 5)))</geom>
      <geom id="3"> MULTIPOLYGON (((30 20, 10 40, 45 40, 30 20)), ((15 5, 40 10, 10 20, 5 10, 15 5)))</geom>
    </response>
    

The XmlSearch API will be modified so the geom parameter can either be WKT or have the form: region:id, where id is the id of the region to use as a geometry. If the region has a geometry then that geometry will be loaded otherwise the bbox will be used to create a polygon geometry.

The CatalogSearcher (part of Csw GetRecords) will be modified to replace elements with the attribute gml:id which have the form: region:id

The actual implementation will consist of the services and a strategy object that can be configured the geonetwork configuration files. The intention is that for a particular application the strategy object can be implemented and configured for use. The default implementation will be the same as

Backwards Compatibility Issues

none

Risks

Participants

• As above