Openlayers 4 – a parametric view is defined in Geoserver, and flitered in Openlayers through javascript – filter parameters are retrieved through an Ajax request querying the source layer in Postgres/Postgis. The layer is refined and point locations are returned and displayed. In addition, on-click events trigger retrieval of point attributes based on GeoJson.
A corresponding bounding-box is returned through an additional Postgis request, querying st_extent of the features’ geometries.
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