Dap:Attribute Extension Example 4

From OPeNDAP Documentation

1 Example 4

Here we mingle WCS content into the DDX document. In this example the wcs:CoverageDescription contains/encapsulated the DDX content. In addition, key components of the coverage such as the wcs:Field elements are correctly associated with the DDX elements that they are describing.


1.1 Source XML

<?xml version="1.0" encoding="UTF-8"?>
<Dataset name="200803061600_HFRadar_USEGC_6km_rtv_SIO.nc"
        xmlns="http://xml.opendap.org/ns/DAP2"
        xmlns:wcs="http://www.opengis.net/wcs/1.1"
        xmlns:ows="http://www.opengis.net/ows/1.1"
        xmlns:owcs="http://www.opengis.net/wcs/1.1/ows"
        xmlns:gml="http://www.opengis.net/gml/3.2"
        xmlns:xlink="http://www.w3.org/1999/xlink"
       >

   <wcs:CoverageDescription>

       <ows:Title>Near-Real Time Surface Ocean Velocity</ows:Title>
       <ows:Abstract>CoverageDescription generated by OPeNDAP WCS UseCase 2.0</ows:Abstract>
       <wcs:Identifier>coverage/200803061600_HFRadar_USEGC_6km_rtv_SIO.nc</wcs:Identifier>
       <wcs:Domain>
           <wcs:SpatialDomain>
               <ows:BoundingBox crs="urn:ogc:def:crs:EPSG::4326">
                   <ows:LowerCorner>-97.8839 21.736</ows:LowerCorner>
                   <ows:UpperCorner>-57.2312 46.4944</ows:UpperCorner>
               </ows:BoundingBox>
           </wcs:SpatialDomain>
           <wcs:TemporalDomain>
               <gml:timePosition>2008-03-27T16:00:00.000Z</gml:timePosition>
           </wcs:TemporalDomain>
       </wcs:Domain>
       <wcs:Range>

           <Attribute name="NC_GLOBAL" type="Container">
               <Attribute name="Conventions" type="String">
                   <value>CF-1.1</value>
               </Attribute>
               <Attribute name="title" type="String">
                   <value>Near-Real Time Surface Ocean Velocity</value>
               </Attribute>
               <Attribute name="institution" type="String">
                   <value>Scripps Institution of Oceanography</value>
               </Attribute>
               <Attribute name="source" type="String">
                   <value>Surface Ocean HF-Radar</value>
               </Attribute>
               <Attribute name="history" type="String">
                   <value>12-Mar-2008 22:26:19: NetCDF file created</value>
               </Attribute>
           </Attribute>

           <Grid name="u">
                 <wcs:Field>
                    <ows:Title>surface_eastward_sea_water_velocity</ows:Title>
                    <ows:Abstract>Eastward component of a 2D sea surface velocity vector.</ows:Abstract>
                    <wcs:Identifier>u</wcs:Identifier>
                    <wcs:Definition>
                       <ows:AnyValue/>
                    </wcs:Definition>
                    <wcs:NullValue>-32768</wcs:NullValue>
                    <owcs:InterpolationMethods>
                       <owcs:DefaultMethod>nearest</owcs:DefaultMethod>
                    </owcs:InterpolationMethods>
                 </wcs:Field>
               <Attribute name="standard_name" type="String">
                   <value>surface_eastward_sea_water_velocity</value>
               </Attribute>
               <Attribute name="units" type="String">
                   <value>m s-1</value>
               </Attribute>
               <Attribute name="_FillValue" type="Int16">
                   <value>-32768</value>
               </Attribute>
               <Attribute name="scale_factor" type="Float32">
                   <value>0.009999999776</value>
               </Attribute>
               <Attribute name="ancillary_variables" type="String">
                   <value>DOPx</value>
               </Attribute>
               <Array name="u">
                   <Int16/>
                   <dimension name="time" size="1"/>
                   <dimension name="lat" size="460"/>
                   <dimension name="lon" size="701"/>
               </Array>
               <Map name="time">
                   <Int32/>
                   <dimension name="time" size="1"/>
               </Map>
               <Map name="lat">
                   <Float32/>
                   <dimension name="lat" size="460"/>
               </Map>
               <Map name="lon">
                   <Float32/>
                   <dimension name="lon" size="701"/>
               </Map>
           </Grid>

       </wcs:Range>

       <wcs:SupportedCRS>urn:ogc:def:crs:EPSG::4326</wcs:SupportedCRS>
       <wcs:SupportedFormat>netcdf-cf1.0</wcs:SupportedFormat>
       <wcs:SupportedFormat>dap2.0</wcs:SupportedFormat>
   </wcs:CoverageDescription>
   <dataBLOB href=""/>

</Dataset>

1.2 Namespace Blocking Transform

Returns all elements NOT in the DAP2 namespace. Or in other words, discard elements in the DAP2 namespace:

<xsl:stylesheet version="1.0"
               xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
               xmlns:dap="http://xml.opendap.org/ns/DAP2" >
   <xsl:output method='xml' version='1.0' encoding='UTF-8' indent='yes'/>

   <xsl:strip-space elements="*" />

   <xsl:template match="*">
       <xsl:choose>
           <xsl:when test="namespace-uri()!='http://xml.opendap.org/ns/DAP2'">
               <xsl:copy >
                   <xsl:call-template name="textAndattributes" />
                   <xsl:apply-templates />
               </xsl:copy>
           </xsl:when>
           <xsl:otherwise>
               <xsl:apply-templates />
           </xsl:otherwise>
       </xsl:choose>
   </xsl:template>

   <xsl:template  match="@*|text()" />

   <xsl:template name="textAndattributes" ><xsl:copy-of select="text()|@*" /></xsl:template>

</xsl:stylesheet>

1.3 Result

The extracted wcs:CoverageDescription element:

<wcs:CoverageDescription xmlns="http://xml.opendap.org/ns/DAP2" xmlns:wcs="http://www.opengis.net/wcs/1.1"
                        xmlns:ows="http://www.opengis.net/ows/1.1"
                        xmlns:owcs="http://www.opengis.net/wcs/1.1/ows"
                        xmlns:gml="http://www.opengis.net/gml/3.2"
                        xmlns:xlink="http://www.w3.org/1999/xlink">
  <ows:Title>Near-Real Time Surface Ocean Velocity</ows:Title>
  <ows:Abstract>CoverageDescription generated by OPeNDAP WCS UseCase 2.0</ows:Abstract>
  <wcs:Identifier>coverage/200803061600_HFRadar_USEGC_6km_rtv_SIO.nc</wcs:Identifier>
  <wcs:Domain>
     <wcs:SpatialDomain>
        <ows:BoundingBox crs="urn:ogc:def:crs:EPSG::4326">
           <ows:LowerCorner>-97.8839 21.736</ows:LowerCorner>
           <ows:UpperCorner>-57.2312 46.4944</ows:UpperCorner>
        </ows:BoundingBox>
     </wcs:SpatialDomain>
     <wcs:TemporalDomain>
        <gml:timePosition>2008-03-27T16:00:00.000Z</gml:timePosition>
     </wcs:TemporalDomain>
  </wcs:Domain>
  <wcs:Range>
     <wcs:Field>
        <ows:Title>surface_eastward_sea_water_velocity</ows:Title>
        <ows:Abstract>Eastward component of a 2D sea surface velocity vector.</ows:Abstract>
        <wcs:Identifier>u</wcs:Identifier>
        <wcs:Definition>
           <ows:AnyValue/>
        </wcs:Definition>
        <wcs:NullValue>-32768</wcs:NullValue>
        <owcs:InterpolationMethods>
           <owcs:DefaultMethod>nearest</owcs:DefaultMethod>
        </owcs:InterpolationMethods>
     </wcs:Field>
  </wcs:Range>
  <wcs:SupportedCRS>urn:ogc:def:crs:EPSG::4326</wcs:SupportedCRS>
  <wcs:SupportedFormat>netcdf-cf1.0</wcs:SupportedFormat>
  <wcs:SupportedFormat>dap2.0</wcs:SupportedFormat>
</wcs:CoverageDescription>

1.4 Namespace Passing Transform

Returns all elements NOT in the DAP2 namespace. Or in other words, discard elements in the DAP2 namespace:

<xsl:stylesheet version="1.0"
               xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
               xmlns:dap="http://xml.opendap.org/ns/DAP2" >
   <xsl:output method='xml' version='1.0' encoding='UTF-8' indent='yes'/>

   <xsl:strip-space elements="*" />

   <xsl:template match="*">
       <xsl:choose>
           <xsl:when test="namespace-uri()='http://xml.opendap.org/ns/DAP2'">
               <xsl:copy >
                   <xsl:call-template name="textAndattributes" />
                   <xsl:apply-templates />
               </xsl:copy>
           </xsl:when>
           <xsl:otherwise>
               <xsl:apply-templates />
           </xsl:otherwise>
       </xsl:choose>
   </xsl:template>

   <xsl:template  match="@*|text()" />

   <xsl:template name="textAndattributes" ><xsl:copy-of select="text()|@*" /></xsl:template>

</xsl:stylesheet>

1.5 Result

The DAP2 DDX document minus the foreign namespace XML:
<Dataset xmlns="http://xml.opendap.org/ns/DAP2" xmlns:wcs="http://www.opengis.net/wcs/1.1"
         xmlns:ows="http://www.opengis.net/ows/1.1"
         xmlns:owcs="http://www.opengis.net/wcs/1.1/ows"
         xmlns:gml="http://www.opengis.net/gml/3.2"
         xmlns:xlink="http://www.w3.org/1999/xlink"
         name="200803061600_HFRadar_USEGC_6km_rtv_SIO.nc">
   <Attribute name="NC_GLOBAL" type="Container">
      <Attribute name="Conventions" type="String">
         <value>CF-1.1</value>
      </Attribute>
      <Attribute name="title" type="String">
         <value>Near-Real Time Surface Ocean Velocity</value>
      </Attribute>
      <Attribute name="institution" type="String">
         <value>Scripps Institution of Oceanography</value>
      </Attribute>
      <Attribute name="source" type="String">
         <value>Surface Ocean HF-Radar</value>
      </Attribute>
      <Attribute name="history" type="String">
         <value>12-Mar-2008 22:26:19: NetCDF file created</value>
      </Attribute>
   </Attribute>
   <Grid name="u">
      <Attribute name="standard_name" type="String">
         <value>surface_eastward_sea_water_velocity</value>
      </Attribute>
      <Attribute name="units" type="String">
         <value>m s-1</value>
      </Attribute>
      <Attribute name="_FillValue" type="Int16">
         <value>-32768</value>
      </Attribute>
      <Attribute name="scale_factor" type="Float32">
         <value>0.009999999776</value>
      </Attribute>
      <Attribute name="ancillary_variables" type="String">
         <value>DOPx</value>
      </Attribute>
      <Array name="u">
         <Int16/>
         <dimension name="time" size="1"/>
         <dimension name="lat" size="460"/>
         <dimension name="lon" size="701"/>
      </Array>
      <Map name="time">
         <Int32/>
         <dimension name="time" size="1"/>
      </Map>
      <Map name="lat">
         <Float32/>
         <dimension name="lat" size="460"/>
      </Map>
      <Map name="lon">
         <Float32/>
         <dimension name="lon" size="701"/>
      </Map>
   </Grid>
   <dataBLOB href=""/>
</Dataset>