spatial-d4science/doc/spatial-search.rst

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Spatial Search
==============
To enable the spatial query you need to add the `spatial_query` plugin to your
ini file (See `Configuration`_). This plugin requires the `spatial_metadata`
plugin.
The extension adds the following call to the CKAN search API, which returns
datasets with an extent that intersects with the bounding box provided::
/api/2/search/dataset/geo?bbox={minx,miny,maxx,maxy}[&crs={srid}]
If the bounding box coordinates are not in the same projection as the one
defined in the database, a CRS must be provided, in one of the following
forms:
- urn:ogc:def:crs:EPSG::4326
- EPSG:4326
- 4326
As of CKAN 1.6, you can integrate your spatial query in the full CKAN
search, via the web interface (see the `Spatial Query Widget`_) or
via the `action API`__, e.g.::
POST http://localhost:5000/api/action/package_search
{
"q": "Pollution",
"extras": {
"ext_bbox": "-7.535093,49.208494,3.890688,57.372349"
}
}
__ http://docs.ckan.org/en/latest/apiv3.html
Geo-Indexing your datasets
--------------------------
In order to make a dataset queryable by location, an special extra must
be defined, with its key named 'spatial'. The value must be a valid GeoJSON_
geometry, for example::
{"type":"Polygon","coordinates":[[[2.05827, 49.8625],[2.05827, 55.7447], [-6.41736, 55.7447], [-6.41736, 49.8625], [2.05827, 49.8625]]]}
or::
{ "type": "Point", "coordinates": [-3.145,53.078] }
.. _GeoJSON: http://geojson.org
Every time a dataset is created, updated or deleted, the extension will synchronize
the information stored in the extra with the geometry table.
Spatial Search Widget
---------------------
**Note**: this plugin requires CKAN 1.6 or higher.
To enable the search map widget you need to add the `spatial_query_widget` plugin to your
ini file (See `Configuration`_). You also need to load both the `spatial_metadata`
and the `spatial_query` plugins.
When the plugin is enabled, a map widget will be shown in the dataset search form,
where users can refine their searchs drawing an area of interest.