I'm trying to customize rendering of map tiles from a government WMS server. When I use the GetStyles WMS query to retrieve the SLD for a layer, then feed that SLD directly back in a GetMap query, the server returns an error.
I'm a newbie at GIS stuff so I'm probably missing something basic. Here are the gory details.
Here's a request to display a tile from this server using two layers: http://openmaps.gov.bc.ca/mapserver/base3?service=wms&version=1.1.1&request=GetMap&styles=&srs=EPSG%3A4326&width=256&height=256&format=image%2Fpng&layers=BC_WATER_LINES_500M,BC_MAJOR_CITIES_POINTS_500M&BBOX=-122.343750,54.977614,-120.937500,55.776573
The capabilities for the WMS do include user styles:
<UserDefinedSymbolization SupportSLD="1" UserLayer="0" UserStyle="1" RemoteWFS="0"/>
I used this request to get the SLD XML document for just the cities layer: http://openmaps.gov.bc.ca/mapserver/base3?service=WMS&version=1.1.1&request=GetStyles&layers=BC_MAJOR_CITIES_POINTS_500M
It returns good looking XML:
<?xml version="1.0" encoding="UTF-8"?>
<StyledLayerDescriptor version="1.0.0" xmlns="http://www.opengis.net/sld" xmlns:gml="http://www.opengis.net/gml" xmlns:ogc="http://www.opengis.net/ogc" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/sld http://schemas.opengis.net/sld/1.0.0/StyledLayerDescriptor.xsd">
<NamedLayer>
<Name>BC_MAJOR_CITIES_POINTS_500M</Name>
<UserStyle>
<FeatureTypeStyle>
<Rule>
<Name>City</Name>
<ogc:Filter><ogc:PropertyIsEqualTo><ogc:PropertyName>fcode</ogc:PropertyName><ogc:Literal>AR05500000</ogc:Literal></ogc:PropertyIsEqualTo></ogc:Filter>
<MinScaleDenominator>325000.010000</MinScaleDenominator>
<MaxScaleDenominator>2000000.000000</MaxScaleDenominator>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>circle</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>10</Size>
</Graphic>
</PointSymbolizer>
<TextSymbolizer>
<Label>NAME</Label>
<Font>
<CssParameter name="font-family">arial</CssParameter>
<CssParameter name="font-weight">bold</CssParameter>
<CssParameter name="font-size">9.00</CssParameter>
</Font>
<LabelPlacement>
<PointPlacement>
<AnchorPoint>
<AnchorPointX>0.5</AnchorPointX>
<AnchorPointY>0.5</AnchorPointY>
</AnchorPoint>
</PointPlacement>
</LabelPlacement>
<Fill>
<CssParameter name="fill">#ffffff</CssParameter>
</Fill>
</TextSymbolizer>
</Rule>
<Rule>
<Name>District Municipality</Name>
<ogc:Filter><ogc:PropertyIsEqualTo><ogc:PropertyName>fcode</ogc:PropertyName><ogc:Literal>AR08750000</ogc:Literal></ogc:PropertyIsEqualTo></ogc:Filter>
<MinScaleDenominator>325000.010000</MinScaleDenominator>
<MaxScaleDenominator>2000000.000000</MaxScaleDenominator>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>circle</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>8</Size>
</Graphic>
</PointSymbolizer>
<TextSymbolizer>
<Label>NAME</Label>
<Font>
<CssParameter name="font-family">arial</CssParameter>
<CssParameter name="font-weight">bold</CssParameter>
<CssParameter name="font-size">9.00</CssParameter>
</Font>
<LabelPlacement>
<PointPlacement>
<AnchorPoint>
<AnchorPointX>0.5</AnchorPointX>
<AnchorPointY>0.5</AnchorPointY>
</AnchorPoint>
</PointPlacement>
</LabelPlacement>
<Fill>
<CssParameter name="fill">#ffffff</CssParameter>
</Fill>
</TextSymbolizer>
</Rule>
<Rule>
<Name>Town</Name>
<ogc:Filter><ogc:PropertyIsEqualTo><ogc:PropertyName>fcode</ogc:PropertyName><ogc:Literal>AR31250000</ogc:Literal></ogc:PropertyIsEqualTo></ogc:Filter>
<MinScaleDenominator>325000.010000</MinScaleDenominator>
<MaxScaleDenominator>2000000.000000</MaxScaleDenominator>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>square</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>4</Size>
</Graphic>
</PointSymbolizer>
<TextSymbolizer>
<Label>NAME</Label>
<Font>
<CssParameter name="font-family">arial</CssParameter>
<CssParameter name="font-weight">bold</CssParameter>
<CssParameter name="font-size">9.00</CssParameter>
</Font>
<LabelPlacement>
<PointPlacement>
<AnchorPoint>
<AnchorPointX>0.5</AnchorPointX>
<AnchorPointY>0.5</AnchorPointY>
</AnchorPoint>
</PointPlacement>
</LabelPlacement>
<Fill>
<CssParameter name="fill">#ffffff</CssParameter>
</Fill>
</TextSymbolizer>
</Rule>
<Rule>
<Name>Village</Name>
<ogc:Filter><ogc:PropertyIsEqualTo><ogc:PropertyName>fcode</ogc:PropertyName><ogc:Literal>AR32700000</ogc:Literal></ogc:PropertyIsEqualTo></ogc:Filter>
<MinScaleDenominator>325000.010000</MinScaleDenominator>
<MaxScaleDenominator>2000000.000000</MaxScaleDenominator>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>square</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>4</Size>
</Graphic>
</PointSymbolizer>
<TextSymbolizer>
<Label>NAME</Label>
<Font>
<CssParameter name="font-family">arial</CssParameter>
<CssParameter name="font-weight">bold</CssParameter>
<CssParameter name="font-size">9.00</CssParameter>
</Font>
<LabelPlacement>
<PointPlacement>
<AnchorPoint>
<AnchorPointX>0.5</AnchorPointX>
<AnchorPointY>0.5</AnchorPointY>
</AnchorPoint>
</PointPlacement>
</LabelPlacement>
<Fill>
<CssParameter name="fill">#ffffff</CssParameter>
</Fill>
</TextSymbolizer>
</Rule>
<Rule>
<Name>Village - Unincorporated</Name>
<ogc:Filter><ogc:PropertyIsEqualTo><ogc:PropertyName>fcode</ogc:PropertyName><ogc:Literal>AR32700110</ogc:Literal></ogc:PropertyIsEqualTo></ogc:Filter>
<MinScaleDenominator>325000.010000</MinScaleDenominator>
<MaxScaleDenominator>2000000.000000</MaxScaleDenominator>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>square</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>4</Size>
</Graphic>
</PointSymbolizer>
<TextSymbolizer>
<Label>NAME</Label>
<Font>
<CssParameter name="font-family">arial</CssParameter>
<CssParameter name="font-weight">bold</CssParameter>
<CssParameter name="font-size">9.00</CssParameter>
</Font>
<LabelPlacement>
<PointPlacement>
<AnchorPoint>
<AnchorPointX>0.5</AnchorPointX>
<AnchorPointY>0.5</AnchorPointY>
</AnchorPoint>
</PointPlacement>
</LabelPlacement>
<Fill>
<CssParameter name="fill">#ffffff</CssParameter>
</Fill>
</TextSymbolizer>
</Rule>
</FeatureTypeStyle>
</UserStyle>
</NamedLayer>
</StyledLayerDescriptor>
I made this file available, unmodified, on the web at http://junkpile.net/misc/sld_unmodified.xml
If I then make a request using this SLD in the URL: http://openmaps.gov.bc.ca/mapserver/base3?service=WMS&version=1.1.1&request=GetMap&styles=&srs=EPSG%3A4326&width=256&height=256&format=image%2Fpng&layers=BC_WATER_LINES_500M,BC_MAJOR_CITIES_POINTS_500M&BBOX=-122.343750,54.977614,-120.937500,55.776573&sld=http%3A%2F%2Fjunkpile.net%2Fmisc%2Fsld_unmodified.xml
The server returns this error:
<?xml version='1.0' encoding="ISO-8859-1" standalone="no" ?>
<!DOCTYPE ServiceExceptionReport SYSTEM "http://schemas.opengis.net/wms/1.1.1/exception_1_1_1.dtd">
<ServiceExceptionReport version="1.1.1">
<ServiceException>
msDrawMap(): Image handling error. Failed to draw layer named 'BC_MAJOR_CITIES_POINTS_500M'.
msSDELayerNextShape(): SDE error. SE_stream_fetch(): Underlying DBMS error. (-51)
agg2RenderTruetypeSymbol(): TrueType Font error. AGG error loading font ()
agg2RenderTruetypeSymbol(): TrueType Font error. AGG error loading font ()
msDrawMap(): Image handling error. Unable to initialize image.
msPrepareImage(): GD library error. Unable to initialize image.
msDrawMap(): Image handling error. Unable to initialize image.
msPrepareImage(): GD library error. Unable to initialize image.
</ServiceException>
</ServiceExceptionReport>
What am I doing wrong? Is there some misconfiguration on the server side, or do I have a fundamental misunderstanding about how user SLD files are applied, or both?
FWIW, I also tried including the SLD in SLD_BODY but ran into URL length limits... tried including the SLD in post data but couldn't find a DTD or XSD for the GetMap XML post format that MapServer expects. The lack of documentation/examples is a challenge.
EDIT: I still don't understand why this isn't working, since the SLD came directly from the server in question. But I am able to successfully apply styles if I use ogc:PropertyIsLike instead of ogc:PropertyIsEqualTo. I guess this is a bug in MapServer?
