OpenGIS
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Specification OGC 04-094
Copyright © Open Geospatial Consortium, Inc 2005
12
Response objects should be accompanied by other HTTP entity headers as appropriate and to the extent possible. In particular, the Expires and Last-Modified headers provide
important information for caching; Content-Length may be used by clients to know when data transmission is complete and to efficiently allocate space for results, and Content-
Encoding or Content-Transfer-Encoding may be necessary for proper interpretation of the results.
6.5 Request encoding
This document defines two methods of encoding WFS requests. The first uses XML as the encoding language, and is intended to be used with HTTP POST method. The second
encoding uses keyword-value pairs KVP to encode the various parameters of a request and is intended to be used with HTTP GET. An example of a keyword value pair is:
REQUEST=GetCapabilities
where REQUEST is the keyword and GetCapabilities is the value. In both cases, the response to a request or exception reporting must be identical.
Table 2 correlates WFS operations and their encoding semantics as defined in this specification.
Table 2 – Operation Request Encoding
Operation Request Encoding
GetCapabilities XML KVP
DescribeFeatureType XML KVP
GetGmlObject XML KVP
LockFeature XML KVP
Transaction XML limited KVP
KVP =
keyword-value pair
This document mandates the use of GML for the XML encoding of the state of geographic features. A complete description of this encoding can be found in document
[2].
6.5.1 Request encoding and HTTP method
The following matrix correlated WFS request encoding with each of the supported HTTP methods GET and POST. The value in each cell defines the expected MIME type for
the encodingrequest method combination. The value Not Applicable means that the encodingrequest method combination is supported but a MIME type is not applicable.
An empty cell indicates that the combination is not supported.
OpenGIS
©
Specification OGC 04-094
Copyright © Open Geospatial Consortium, Inc 2005
13
Table 2b – Request encoding and transport methods
