DescribeFeatureType request

Request parameter
Request example

Request parameter

Parameters for the DescribeFeatureType operation are listed in the following table.

Table 1 Parameters for DescribeFeatureType operation

Request parameter	O/M	Description
VERSION	Mandatory	Request version. Request WFS 2.0.0 service. The request version number needs to be set to 2.0.0.
SERVICE	Mandatory	Service type. Request WFS 2.0.0 service. The request type needs to be set to WFS.
REQUEST	Mandatory	Name of WFS request. Request DescribeFeatureType operation. The request name should be set to DescribeFeatureType.
TYPENAME	Optional	Feature types. A comma separated list of feature types to describe. If no value is specified that is to be interpreted as all feature types provided by WFS 2.0.0.
OUTPUTFORMAT	Optional	Output format. Defines the encoding format of the response result after implementing the DescribeFeatureType operation. Two output formats are supported by default and the two formats are declared in the Capabilities XML document. The two formats are "application/gml+xml;version=3.2" and "text/xml;subtype=gml/3.2".
NAMESPACES	Optional	Namespace. Used to specify namespaces and their prefixes. The format shall be xmlns(prefix,escaped_url). If the prefix is not specified then the default namespace shall be assumed. More that one namespace may be bound by specifying a comma separated list of xmlns() values.
VSPs	Optional	Vendor-specific parameter. A server may implement additional KVP parameters that are not part of this International Standard. These are known as vendor-specific parameters. VSPs allow vendors to specify additional parameters that will enhance the results of requests. A server shall produce valid results even if the VSPs are missing, malformed or if VSPs are supplied that are not known to the server. Unknown VSPs shall be ignored. A server may choose not to advertise some or all of its VSPs. If VSPs are included in the Capabilities XML, the ows:ExtendedCapabilities element shall be extended accordingly. Additional schema documents may be imported containing the extension(s) of the ows:ExtendedCapabilities element. Any advertised VSP shall include or reference additional metadata describing its meaning. WFS implementers should choose VSP names with care to avoid clashes with WFS parameters defined in this International Standard. This parameter is not supported by SuperMap iServer currently.

Request example

KVP encoding request method for the DescribeFeatureType operation is as follows:

<ServiceRoot>?SERVICE=WFS&VERSION=version&REQUEST=DescribeFeatureType&OUTPUTFORMAT=outputformat&TYPENAME=type_list

ServiceRoot is the URI root directory of the service, please refer to Setting the Service URI.

For example, when the SuperMap iServer WFS 2.0.0 server at local computer has been started successfully, the URI to access the DescribeFeatureType operation is: http://localhost:8090/iserver/services/data-world/wfs200?SERVICE=WFS&VERSION=2.0.0&REQUEST=DescribeFeatureType&OUTPUTFORMAT=text/xml;subtype=gml/3.2&TYPENAME=World:Countries.

Please refer to Response example to see the result.

XML encoding request method for the DescribeFeatureType operation is as follows:

That is, to implement the POST request onhttp://localhost:8090/iserver/services/data-world/wfs200 and the request body is as follows:

<?xml version="1.0" ?>

<DescribeFeatureType service="WFS" version="2.0.0"

xmlns="http://www.opengis.net/wfs/2.0" xmlns:World="http://www.supermap.com.cn/World"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://www.opengis.net/wfs/2.0

http://schemas.opengis.net/wfs/2.0.0/wfs.xsd">

<TypeName>World:Countries</TypeName>

</DescribeFeatureType>

The response to this request example is the same as the response of KVP encoding request, see: Response example.