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Meaning Parameter
Parameter name=Metadata AnyValue
Meaning A comma-separated ordered list of zero or more names of sections of metadata
to be returned. If not set or empty, it means do not send metadata with node information.
If set to All, it means send all metadata with node information. At least the value of All shall be implemented.
A complete list shall be provided as part of the Capabilities response to the GetCollections request.
Shall be implemented by both client and server. Meaning
Parameter Parameter name=Depth
AllowedValues Value0Value
Value1Value ValueAllValue
AllowedValues DefaultValue0DefaultValue
MeaningSpecifies how deep the collection counter shall go down the tree. It has three possible values: 0, 1 or All.
If not set or empty, implies Depth=0. Shall be implemented by both client and server.
0: only send information about this node. 1: Client received number of child nodes under root or specified node.
All: Client receives all the node counts below specified node. Meaning
Parameter Parameter name=Bbox
AnyValue MeaningBounding box to filter collections wholly outside the box.Meaning
Parameter
Parameter name=CRS AllowedValues
ValueEPSG:4326Value ValueEPSG:4269Value
ValueEPSG:32645Value AllowedValues
MeaningCoordinate reference system for BBoxMeaning Parameter
Parameter name=Time AnyValue
MeaningISO 8601 time intervalMeaning Parameter
Operation
20.4.7 Response
The response from a GetCollectionsrequest can be in a format of the clients choosing from a list of formats that the server supports. If the response is of MIME type applicationxml then
the XSD for the response is specified below.
20.4.7.1 XML Response schema
See [WAMI XSD] element “ExceptionReport” for requests with errors. See [WAMI XSD] element “CS_Collections” for normal applicationxml result content.
20.4.7.2 Exceptions
An error in a GetCollections request may generate the following exceptionCodes:
Copyright © 2012 Open Geospatial Consortium
67 1. MissingParameterValue
2. InvalidParameterValue 3. OptionNotSupported
4. NoApplicableCode
20.4.7.3 Example GetCollection Response
A sample request:
http:example.compath?Service=CSRequest=GetCollectionsVersion=1.0.2NID=node6Metadata=Co llection,GeoBoxDepth=1Format=applicationxml
A sample response:
?xml version=1.0 encoding=UTF-8? CS_Collections xmlns=http:www.pixia.comwamiv101 xmlns:ows=http:www.opengis.netows2.0
xmlns:xlink=http:www.w3.org1999xlink xmlns:xsi=http:www.w3.org2001XMLSchema-instance xsi:schemaLocation=http:www.pixia.comwami wami_1_0_1.xsd
http:www.opengis.netows2.0 owsAll.xsd http:www.w3.org1999xlink xlinks.xsd
-- depth could have been All -- DescriptionDetailed statistics about a snapshot of the tree from a given Node ID
NIDDescription Parent NID=node5
Service name=CS ows:DCP
ows:HTTP ows:Get xlink:href=http:example.comCS?Request=GetCollectionsamp;NID=node5
ows:HTTP ows:DCP
Service Parent
Node NID=node6 parentNID=node5 DescriptionNode 6 descriptionDescription
Node NID=node7 CID=collection7 parentNID=node6 Metadata
Collection startFrame=0
endFrame=15 frameCount=16
startTime=2010-01-01T15:15:15.0Z endTime=2010-01-01T11:15:15.0Z
timeSpan=PT1H frameInterval=PT1S
GeoBox nativeCRS=EPSG:4236 BoundingBox crs=EPSG:4326 minx=1.0 maxx=2.0 miny=1.0 maxy=2.0 resx=50 resy=50
GeoBox Metadata
Node Node
CS_Collections
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Time
Collectio n A
Colle ction
B Colle
ction D
Collection C
A B
C D
Collections A, C and D intersect with this Bbox
Collections A, B and C intersect with this Bbox
Collections A, B and D intersect with this Time window
Collections B, C and D intersect with this Time window
Only Collections A and B intersect with this Bbox and Time window
Only Collections C and D intersect with this Bbox and Time window
Interaction of GetCollectionCount and GetCollections with Bbox and Time
T
in‐1
T
out‐1
T
in‐2
T
out‐2
Figure 9: Filter GetCollectionCount and GetCollections by Bbox and Time
20.5 Filtering on Bbox, Time, NID, Depth and Metadata
Time and Bbox act as filters in tandem. If Time andor Bbox are set in a client request, all Collections wholly outside the bounding box or temporal range are excluded from the response.
The rest are included. Quantity and count of data is further controlled by NID and Depth. The amount of metadata included in the response is controlled by Metadata. This applies to both
GetCollectionCount and GetCollections.
21 What a Collection Service shall not do
Collection Service is not a search service. It shall not perform arbitrary search operations on collection trees. Metadata based tree filtering and similar non-linear search query operations on a
set of collections shall be implemented within a Query Service.
A CS has CRS, Bbox, and Time parameters allowing it to be consistent with and IS, VS requests. By virtue of having these requests, a client can filter or discover data spatiotemporally. Further, it
can limit the quantity of data travelling on the network by starting from a specific node and going down tree levels incrementally. This filtering enables data discovery. Search is, as stated
above, in the realm of a Query Service.
