I'm posting this as a new question as a follow-up to this one Geoserver SLD: Dynamic Variable Substitution
I am struggling to get SLD variable substitution to work where I have an environment variable representing an attribute table column heading. The layer is rendered via Leaflet from GeoServer. Example is here https://www.climatejust.org.uk/map-dev/ (two map layers: 'Social Heat Vulnerability Index' and 'Sensitivity').
Here my two layers in Leaflet, one with an attribute column named ZH_VULN_IN and other SENS_IND.
var ZH_VULN_IN = L.tileLayer.wms(cj_server, {
layers: 'cj18:FINAL_SSVI_FLOOD_HEAT_04022014',
env: 'att:ZH_VULN_IN',
tiles: true,
format: 'image/png',
transparent: true
})
var SENS_IND = L.tileLayer.wms(cj_server, {
layers: 'FINAL_SSVI_FLOOD_HEAT_04022014',
env: 'att:SENS_IND',
tiles: true,
format: 'image/png',
transparent: true
})
The Geoserver log file seems to get the correct env variable passed and I can see this changing when I select either of the two layers but the map does not render.
Log output:
Elevation = []
Env = {ATT=ZH_VULN_IN}
Exceptions = SE_XML
FeatureId = null
FeatureVersion = null
Filter = null
Format = image/png
FormatOptions = {}
Get = true
Height = 256
Interpolations = []
Layers = [org.geoserver.wms.MapLayerInfo@832dfcaf]
MaxFeatures = null
Palette = null
RawKvp = {FORMAT=image/png, TILES=true, STYLES=, WIDTH=256, ENV=att:ZH_VULN_IN, HEIGHT=256, LAYERS=cj18:FINAL_SSVI_FLOOD_HEAT_04022014, REQUEST=GetMap, SRS=EPSG:3857, BBOX=-313086.06785608194,7200979.560689886,0,7514065.628545967, VERSION=1.1.1, SERVICE=WMS, TRANSPARENT=true}
This is my sld file:
<?xml version="1.0" encoding="UTF-8"?>
<StyledLayerDescriptor xmlns="http://www.opengis.net/sld" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:se="http://www.opengis.net/se" xsi:schemaLocation="http://www.opengis.net/sld http://schemas.opengis.net/sld/1.1.0/StyledLayerDescriptor.xsd" xmlns:ogc="http://www.opengis.net/ogc" version="1.1.0" xmlns:xlink="http://www.w3.org/1999/xlink">
<NamedLayer>
<se:Name>FINAL_SSVI_FLOOD_HEAT_04022014</se:Name>
<UserStyle>
<se:Name>FINAL_SSVI_FLOOD_HEAT_04022014</se:Name>
<se:FeatureTypeStyle>
<se:Rule>
<se:Name>-3 - 0</se:Name>
<se:Description>
<se:Title>-3 - 0</se:Title>
</se:Description>
<ogc:Filter xmlns:ogc="http://www.opengis.net/ogc">
<ogc:And>
<ogc:PropertyIsGreaterThanOrEqualTo>
<!--ogc:PropertyName>ZH_VULN_IN</ogc:PropertyName-->
<!-- replace about line with next three lines -->
<ogc:Function name="env">
<ogc:Literal>att</ogc:Literal>
</ogc:Function>
<ogc:Literal>-3</ogc:Literal>
</ogc:PropertyIsGreaterThanOrEqualTo>
<ogc:PropertyIsLessThanOrEqualTo>
<!--ogc:PropertyName>ZH_VULN_IN</ogc:PropertyName-->
<!-- replace about line with next three lines -->
<ogc:Function name="env">
<ogc:Literal>att</ogc:Literal>
</ogc:Function>
<ogc:Literal>0</ogc:Literal>
</ogc:PropertyIsLessThanOrEqualTo>
</ogc:And>
</ogc:Filter>
<se:PolygonSymbolizer>
<se:Fill>
<se:SvgParameter name="fill">#404040</se:SvgParameter>
</se:Fill>
<se:Stroke>
<se:SvgParameter name="stroke">#232323</se:SvgParameter>
<se:SvgParameter name="stroke-width">1</se:SvgParameter>
<se:SvgParameter name="stroke-linejoin">bevel</se:SvgParameter>
</se:Stroke>
</se:PolygonSymbolizer>
</se:Rule>
<se:Rule>
<se:Name>> 0 - 6.8</se:Name>
<se:Description>
<se:Title>> 0 - 7</se:Title>
</se:Description>
<ogc:Filter xmlns:ogc="http://www.opengis.net/ogc">
<ogc:And>
<ogc:PropertyIsGreaterThan>
<!--ogc:PropertyName>ZH_VULN_IN</ogc:PropertyName-->
<!-- replace about line with next three lines -->
<ogc:Function name="env">
<ogc:Literal>att</ogc:Literal>
</ogc:Function>
<ogc:Literal>0</ogc:Literal>
</ogc:PropertyIsGreaterThan>
<ogc:PropertyIsLessThanOrEqualTo>
<!--ogc:PropertyName>ZH_VULN_IN</ogc:PropertyName-->
<!-- replace about line with next three lines -->
<ogc:Function name="env">
<ogc:Literal>att</ogc:Literal>
</ogc:Function>
<ogc:Literal>7</ogc:Literal>
</ogc:PropertyIsLessThanOrEqualTo>
</ogc:And>
</ogc:Filter>
<se:PolygonSymbolizer>
<se:Fill>
<se:SvgParameter name="fill">#ca0020</se:SvgParameter>
</se:Fill>
<se:Stroke>
<se:SvgParameter name="stroke">#232323</se:SvgParameter>
<se:SvgParameter name="stroke-width">1</se:SvgParameter>
<se:SvgParameter name="stroke-linejoin">bevel</se:SvgParameter>
</se:Stroke>
</se:PolygonSymbolizer>
</se:Rule>
</se:FeatureTypeStyle>
</UserStyle>
</NamedLayer>
</StyledLayerDescriptor>
If I uncomment these lines in the SLD file
<!–ogc:PropertyName>ZH_VULN_IN</ogc:PropertyName–>
and then comment out the next three lines the map renders fine using data from the ZH_VULN_IN column but that's not what I want. I want this to change based on the selected map layer. I have tried various approaches based on the previous questions asked about this but with no positive outcome.
Am I missing something obvious?
Best Answer
What you are expanding there is the value of the env variable,
ZH_VULN_IN, which is then compared, as a static string, to7(not very meaningful).What you want to do instead:
The "property" function allows for dynamic property lookup, which would be otherwise unsupported in SLD.