Does GeoServer support FILTERs in GetFeature requests?

Question

I have a web client that filters WFS layers from various servers such as MapServer and GeoServer.

The following URL (encoding and removing whitespace does not make a difference):

https://ows-demo.terrestris.de/geoserver/osm/ows?version=2.0.0&request=GetFeature&service=WFS&typeNames=osm-fuel&count=10&exceptions=xml&filter=<fes:Filter xsi:schemaLocation="http://www.opengis.net/fes/2.0 http://schemas.opengis.net/filter/2.0/filterAll.xsd http://www.opengis.net/gml/3.2 http://schemas.opengis.net/gml/3.2.1/gml.xsd" xmlns:fes="http://www.opengis.net/fes/2.0" xmlns:gml="http://www.opengis.net/gml/3.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><ogc:BBOX>    <ogc:PropertyName>the_geom</ogc:PropertyName><gml:Envelope xmlns:gml="http://www.opengis.net/gml" srsName="EPSG:3857"><gml:lowerCorner>-1400194.9520285155 6560917.375753866</gml:lowerCorner>      <gml:upperCorner>270219.8351193511 7459453.681587799</gml:upperCorner></gml:Envelope>  </ogc:BBOX></fes:Filter>

Returns an exception:

<?xml version="1.0" encoding="UTF-8"?><ows:ExceptionReport xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:ows="http://www.opengis.net/ows/1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0.0" xsi:schemaLocation="http://www.opengis.net/ows/1.1 http://ows-demo.terrestris.de/geoserver/schemas/ows/1.1.0/owsAll.xsd">
<ows:Exception exceptionCode="XML getFeature request SAX parsing error" locator="org.geoserver.ows.XmlRequestReader">
<ows:ExceptionText>org.xml.sax.SAXException: Attempted to construct illegal filter - I dont understand the tag: ogc:BBOX.  HINT: tags are case-sensitive!
Attempted to construct illegal filter - I dont understand the tag: ogc:BBOX.  HINT: tags are case-sensitive!</ows:ExceptionText>
</ows:Exception>
</ows:ExceptionReport>

If I remove the outer <filter></filter> tags I get results:

https://ows-demo.terrestris.de/geoserver/osm/ows?version=2.0.0&request=GetFeature&service=WFS&typeNames=osm-fuel&count=10&exceptions=xml&filter=<ogc:BBOX>    <ogc:PropertyName>the_geom</ogc:PropertyName><gml:Envelope xmlns:gml="http://www.opengis.net/gml" srsName="EPSG:3857"><gml:lowerCorner>-1400194.9520285155 6560917.375753866</gml:lowerCorner>      <gml:upperCorner>270219.8351193511 7459453.681587799</gml:upperCorner></gml:Envelope></ogc:BBOX>

However these results don't appear to be spatially filtered - the same number of results are returned with or without the filter.

The bbox approach (suggested in the GeoServer docs works fine. The following returns the expected results:

https://ows-demo.terrestris.de/geoserver/osm/ows?version=2.0.0&request=GetFeature&service=WFS&typeNames=osm-fuel&count=10&exceptions=xml&bbox=-1400194.9520285155,6560917.375753866,270219.8351193511,7459453.681587799

However I was hoping for an approach that works with both MapServer and GeoServer. Note this approach was working (in 2020) so I'm wondering if something has changed, or a config setting has changed in a more recent version of GeoServer.

With some basic testing it seems as though MapServer does also support the bbox option so it could be possible to switch to this for all servers.

Update

The following request brings back the expected results:

https://ows-demo.terrestris.de/geoserver/osm/ows?version=2.0.0&request=GetFeature&service=WFS&typeNames=osm-fuel&count=10&exceptions=xml&filter=<fes:Filter xmlns:fes="http://www.opengis.net/fes/2.0"><fes:BBOX><fes:ValueReference>the_geom</fes:ValueReference><gml:Envelope xmlns:gml="http://www.opengis.net/gml/3.2" srsName="EPSG:3857"><gml:lowerCorner>-1400194.9520285155 6560917.375753866</gml:lowerCorner><gml:upperCorner>270219.8351193511 7459453.681587799</gml:upperCorner></gml:Envelope></fes:BBOX></fes:Filter>

Note:

• BBOX is in the fes namespace (thanks @ian-turton)
• <fes:ValueReference>the_geom</fes:ValueReference> instead of <ogc:PropertyName>
• namespaces have to be included - without them there is no error but there is no spatial filtering

Answer 1

BBOX lives in the fes namespace not the ogc one if you are using a WFS 2.0.0 server, I have a feeling it might work if you define an ogc namespace rather than an fes one. However, I suspect you need the ogc one for the PropertyName - sadly the examples in the spec don't have any namespaces (which is why I try not to use FES).