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Copyright © 2010 Open Geospatial Consortium
9.2 Request 9.2.1 Request Semantics
Figure 14 describes the schema of a DescribeFeatureType request.
DescribeFeatureType + typeName [0..] : ScopedName
+ outputFormat : CharacterString = textx ml; subtype=gml 3.2 BaseRequest
+ service : Charact erSt ring = W FS {frozen} + version : Charact erSt ring = 2.0. 0 {frozen}
+ handle [0..1] : CharacterString
Figure 14 — DescribeFeatureType request 9.2.2 XML Encoding
The following XML Schema fragment defines the XML encoding of a DescribeFeatureType request:
xsd:element name=DescribeFeatureType type=wfs:DescribeFeatureTypeType xsd:complexType name=DescribeFeatureTypeType
xsd:complexContent xsd:extension base=wfs:BaseRequestType
xsd:sequence xsd:element name=TypeName type=xsd:QName
minOccurs=0 maxOccurs=unbounded xsd:sequence
xsd:attribute name=outputFormat type=xsd:string default=applicationgml+xml; version=3.2
xsd:extension xsd:complexContent
xsd:complexType
9.2.3 KVP Encoding
Table 15 defines the KVP encoding for the DescribeFeatureType request.
Copyright © 2010 Open Geospatial Consortium
57 Table 15 — DescribeFeatureType KVP encoding
URL Component OMa
Description
Common Keywords REQUEST=DescribeFeatureType
See Table 7. Only keywords for all operations or the DescribeFeatureType
operation. TYPENAME
O A comma separated list of feature types to describe. If no value is
specified, the complete application schema offered by the server shall be described.
OUTPUTFORMAT O
Shall support the value applicationgml+xml; version=3.2 indicating that a GML see ISO19136:2007 application schema
shall be generated. A server may support other values to which this International Standard does not assign any meaning.
a O = Optional, M = Mandatory
9.2.4 Parameter discussion 9.2.4.1
typeNames parameter
For XML-encoded requests the typeNames parameter shall be encoded using the typeNames attribute on the wfs:DescribeFeatureType element.
For KVP-encoded requests the typeNames parameter shall be encoded using the TYPENAMES keyword. The typeNames parameter encodes the names of one or more features types that shall be described by the
DescribeFeatureType operation. The set of permissible values for the typeNames parameter shall be the set of feature type names listed in a
servers capabilities document see 8.3.3. If the typeName parameter is omitted, the complete application schemas supported by the server shall be
returned in response.
9.2.4.2 outputFormat parameter
For XML-encoded requests the outputFormat parameter shall encoded using an attribute of the same name on the wfs:DescribeFeatureType element.
For KVP-encoded requests the outputFormat parameter shall be encoded using the keyword OUTPUTFORMAT see 7.6.3.3.
The outputFormat parameter is used to indicate the schema description language that shall be used to describe feature types.
The default value of applicationgml+xml; version=3.2 shall be used to indicate that the features types shall be described using a GML see ISO 19136:2007 application schema. Every WFS that conforms to this
International Standard shall support this default value.
A server may advertise additional values for the outputFormat attribute in its capabilities document see Table 12 indicating that multiple output formats, including previous versions of GML, are supported. However, this
International Standard only assigns meaning to the value applicationgml+xml; version=3.2.
If any such additional outputFormat values are listed in the capabilities document, this International Standard recommends that additional metadata see OGC 06-121r3:2009, Table 32 describing the meaning of the
additional values be included in the capabilities document see 8.3.3.
