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Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved.
8.3.7 GetCapabilities exceptions
When a WPS server encounters an error while performing a GetCapabilities operation, it shall return an exception report message as specified in Clause 8 of [OGC 06-121r3].
The allowed exception codes shall include those listed in Table 5 of Subclause 7.4.1 of [OGC 06-121r3].
9 DescribeProcess operation mandatory
9.1 Introduction
The mandatory DescribeProcess operation allows WPS clients to request a full description of one or more processes that can be executed by the Execute operation. This
description includes the input and output parameters and formats. This description can be used to automatically build a user interface to capture the parameter values to be used to
execute a process instance.
9.2 DescribeProcess operation request
9.2.1 DescribeProcess request parameters
A request to perform the DescribeProcess operation shall include the parameters listed and defined in Table 13. This table specifies the UML data type, source of values, and
multiplicity of each listed parameter, plus the meaning to servers when each optional parameter is not included in the operation request. Although some values listed in the
―Name‖ column appear to contain spaces, they shall not contain spaces.
Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved.
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NOTE 1 The first three parameters listed below are largely copied from Table 26 in Subclause 9.2.1 of
[OGC 06-121r3]. The Identifier parameter is partially copied from Table 31 in Subclause 10.6.1 of that document.
Table 13 — Parameters in DescribeProcess operation request
Name
a
Definition Data type and value
Multiplicity and use
service Service type identifier
Character String type Value is ―WPS‖
One mandatory request
Operation name Character String type
Value is ―DescribeProcess‖ One mandatory
version Specification version
for operation Character String type, not empty
Value is specified by each WPS Implementation Specification and
Schemas version One mandatory
language Language identifier
Character string type, RFC4646 language code of the
human readable text. Must be a language listed in the Capabilities
Languages element. Zero or one optional
Identifier Identifier
Process identifier Character String type, not empty
Value is process Identifier defined in ProcessOfferings section of service
metadata Capabilities document One or more mandatory
One for each desired Process, unordered list
a The name capitalization rules being used here are specified in Subclause 11.6.2 of [OGC 06-121r3].
NOTE 2 The data type of many parameters is specified as ―Character String type, not empty‖. In the
XML Schema Documents specified herein, these parameters are encoded with the xsd:string type, which does NOT require that these strings not be empty.
NOTE 3 The UML class diagrams contained in Subclause C.5 provides a graphical view of the contents
of the DescribeProcess operation request listed in Table 13.
9.2.2 DescribeProcess HTTP GET request KVP encoding mandatory
All WPS servers shall implement HTTP GET transfer of the DescribeProcess operation request, using KVP encoding. The KVP encoding of the DescribeProcess operation
request shall use the parameters specified in Table 14. The parameters listed in Table 14 shall be as specified in Table 13 above.