8.16. TrackLabelProcess

The TrackLabelProcess returns a single feature that is the head of a track of related simple features, useful for styling. It accepts the following parameters:

Parameter	Description
data	Input features
track	Track attribute to use for grouping features
dtg	Date attribute to use for ordering tracks

8.16.1. TrackLabel Example

The following XML is an example of the TrackLabelProcess:

<?xml version="1.0" encoding="UTF-8"?>
<wps:Execute version="1.0.0"
    service="WPS"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://www.opengis.net/wps/1.0.0"
    xmlns:wfs="http://www.opengis.net/wfs"
    xmlns:wps="http://www.opengis.net/wps/1.0.0"
    xmlns:ows="http://www.opengis.net/ows/1.1"
    xmlns:xlink="http://www.w3.org/1999/xlink"
    xsi:schemaLocation="http://www.opengis.net/wps/1.0.0 http://schemas.opengis.net/wps/1.0.0/wpsAll.xsd">
  <ows:Identifier>geomesa:TrackLabel</ows:Identifier>
  <wps:DataInputs>
    <wps:Input>
      <ows:Identifier>data</ows:Identifier>
      <wps:Reference mimeType="text/xml" xlink:href="http://geoserver/wfs" method="POST">
        <wps:Body>
          <wfs:GetFeature service="WFS" version="1.0.0" outputFormat="GML2" xmlns:cabs="cabs">
            <wfs:Query typeName="cabs:Cabs_features"/>
          </wfs:GetFeature>
        </wps:Body>
      </wps:Reference>
    </wps:Input>
    <wps:Input>
      <ows:Identifier>track</ows:Identifier>
      <wps:Data>
        <wps:LiteralData>CabId</wps:LiteralData>
      </wps:Data>
    </wps:Input>
    <wps:Input>
      <ows:Identifier>dtg</ows:Identifier>
      <wps:Data>
        <wps:LiteralData>Date</wps:LiteralData>
      </wps:Data>
    </wps:Input>
  </wps:DataInputs>
  <wps:ResponseForm>
    <wps:RawDataOutput mimeType="application/json">
      <ows:Identifier>result</ows:Identifier>
    </wps:RawDataOutput>
  </wps:ResponseForm>
</wps:Execute>

Assuming the above XML is in a file named TrackLabelProcess_wps.xml, it can be invoked with the following curl to GeoServer:

curl -v -u admin:geoserver -H "Content-Type: text/xml" -d@TrackLabelProcess_wps.xml localhost:8080/geoserver/wps