WFS vendor parameters¶

CQL filters¶

In WFS GetFeature GET requests, the cql_filter parameter can be used to specify a filter in ECQL (Extended Common Query Language) format. ECQL provides a more compact and readable syntax compared to OGC XML filters.

For full details see the ECQL Reference and CQL and ECQL tutorial.

The following example illustrates a GET request OGC filter:

filter=%3CFilter%20xmlns:gml=%22http://www.opengis.net/gml%22%3E%3CIntersects%3E%3CPropertyName%3Ethe_geom%3C/PropertyName%3E%3Cgml:Point%20srsName=%224326%22%3E%3Cgml:coordinates%3E-74.817265,40.5296504%3C/gml:coordinates%3E%3C/gml:Point%3E%3C/Intersects%3E%3C/Filter%3E

Using ECQL, the identical filter would be defined as follows:

cql_filter=INTERSECTS(the_geom,%20POINT%20(-74.817265%2040.5296504))

Format options¶

The format_options parameter is a container for other parameters that are format-specific. The syntax is:

format_options=param1:value1;param2:value2;...

The supported format option is:

• callback (default is parseResponse)—Specifies the callback function name for the JSONP response format

• id_policy (default is true)- Specifies id generation for the JSON output format. To include feature id in output use an attribute name, or use format_options=id_policy:true for feature id generation. To avoid the use of feature id completely use format_options=id_policy:false.

• filename (default is features or generated from feature type name)- provide a Content-Disposition header indicating the attachment filename (used as a suggestion by browsers saving content to disk using Save-As). For example format_options=filename:content.txt.

• csvseparator (default is `,` )- Specifies a separator that can be used in output csv file

Reprojection¶

As WFS 1.1.0 and 2.0.0 both support data reprojection, GeoServer can store the data in one projection and return GML in another projection. While not part of the specification, GeoServer supports this using WFS 1.0.0 as well. When submitting a WFS GetFeature GET request, you can add this parameter to specify the reprojection SRS as follows:

srsName=<srsName>

The code for the projection is represented by <srsName>, for example EPSG:4326. For POST requests, you can add the same code to the Query element.

XML request validation¶

GeoServer is less strict than the WFS specification when it comes to the validity of an XML request. To force incoming XML requests to be valid, use the following parameter:

strict=[true|false]

The default option for this parameter is false.

For example, the following request is invalid:

<wfs:GetFeature service="WFS" version="1.0.0"
 xmlns:wfs="http://www.opengis.net/wfs">
  <Query typeName="topp:states"/>
</wfs:GetFeature>

The request is invalid for two reasons:

• The Query element should be prefixed with wfs:.

• The namespace prefix has not been mapped to a namespace URI.

That said, the request would still be processed by default. Executing the above command with the strict=true parameter, however, would result in an error. The correct syntax should be:

<wfs:GetFeature service="WFS" version="1.0.0"
 xmlns:wfs="http://www.opengis.net/wfs"
 xmlns:topp="http://www.openplans.org/topp">
  <wfs:Query typeName="topp:states"/>
</wfs:GetFeature>

GetCapabilities namespace filter¶

WFS GetCapabilities requests may be filtered to return only those layers that correspond to a particular namespace by adding the <namespace> parameter to the request.

To apply this filter, add the following code to your request:

namespace=<namespace>

Although providing an invalid namespace will not result in any errors, the GetCapabilities document returned will not contain any layer information.