EO Satellite Tasking Extension for SPS OGC 10-135
8 Additional operations and SOAP binding
8.1 Requirements Class: GetSensorAvailability Operation
Requirements Class http:www.opengis.netspecEOSPS2.0reqgsa
Target Type Server Implementation
Dependency http:www.opengis.netspecEOSPS2.0reqcore
8.1.1 Introduction
This section defines an additional operation that can be implemented by EO SPS servers and clients. The standardization target of this class is a server implementation supporting
retrieval of future sensor availability but most requirements are also applicable to client implementations seeking to support this feature.
Requirement http:www.opengis.netspecEOSPS2.0reqgsacapabilities
Req 40. The GetSensorAvailability operation shall be listed in the capabilities
document of the service.
An EO system may not be available over a period of time for different reasons such as workload, maintenance, etc. The GetSensorAvailability operation allows the client to
obtain a preview of the periods of availability of a sensor before a feasibility study is requested.
The granularity of the provided information is up to the data provider who can choose to describe its exact workload or simply list approximate periods of availability. For
instance, a provider may wish to list a period of one week as soon as the sensor is available for tasking at least during 50 of the period. This allows a provider to choose
the most appropriate granularity of information to help the users while maintaining its exact workload secret.
8.1.2 Data model
The following UML diagram shows the exact model of the GetSensorAvailability operation:
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2011 Open
Geospatial Consortium
77
OGC 10-135 EO Satellite Tasking Extension for SPS
«DataType»
SWES Common:: ExtensibleRequest
«property» «DataType»
SWES Common:: ExtensibleResponse
«property» + extension:
Any [0..]
+ service: CharacterString
+ version: CharacterString
+ extension: Any [0..]
«DataType»
GetSensorAv ailability
«DataType»
GetSensorAv ailabilityResponse
«property» «property»
+ sensor: ScopedName
+ requestPeriod: TM_Period
+ availabilityPeriod: TM_Period [0..] + responsePeriod:
TM_Period
Figure 22 – UML diagram of the GetSensorAvailability operation
8.1.2.1 Operation request – GetSensorAvailability
Sending an instance of the GetSensorAvailability data type to the service performs an SPS EO GetSensorAvailability operation request.
The GetSensorAvailability data type is derived from the ExtensibleRequest data type specified in the SWE Service Model standard [OGC 09-001] and therefore inherits all the
properties contained in that data type. GetSensorAvailability does not restrict the content model of ExtensibleRequest. It shall contain the properties defined for ExtensibleRequest.
In addition, it shall include the properties listed in the following table.
Name Definition
Data Type Multiplicity
sensor Identifier of a sensorprocedure as advertised
in the capabilities. ScopedName One
mandatory requestPeriod
Period during which the client asks for sensor availability.
TM_Period One
1
mandatory 1. The number of periods that can be sent to the server by the client is voluntary restricted to one because the
GetSensorAvailability operation is meant to give the client an overall view of the sensor availability over a certain period of time. If a more precise information is needed the GetFeasibility operation should be used.
8.1.2.2 Operation response – GetSensorAvailabilityResponse
The GetSensorAvailabilityResponse data type represents the response to an SPS EO GetSensorAvailability operation request.
The GetSensorAvailabilityResponse data type is derived from the ExtensibleResponse data type defined in [OGC 09-001] and therefore inherits all the properties contained in
78 Copyright
© 2011
Open Geospatial
Consortium