geoserver CSS-Styling call WPS function

Question

I've a custom WPS function gs:GetStyleSize, that I used to call from SLD like the following:

<FeatureTypeStyle>
    <Rule>
        <PointSymbolizer>
            <Graphic>
                <Mark>
                    <WellKnownName>circle</WellKnownName>
                    <Fill>
                        <CssParameter name="fill">#FF0000</CssParameter>
                    </Fill>
                </Mark>
                <Size>
                   <ogc:Function name="gs:GetStyleSize">
                    <ogc:Function name="parameter">
                        <ogc:Literal>style</ogc:Literal>
                        <ogc:PropertyName>style</ogc:PropertyName>
                    </ogc:Function>
                  </ogc:Function>
                </Size>
            </Graphic>
        </PointSymbolizer>
    </Rule>
</FeatureTypeStyle>

I need to convert this SLD to CSS, I tried the following:

/* @title gold point */
*{
    mark: symbol(circle);
    mark-size: gs:GetStyleSize(style);
    :mark {
        fill: #ffcc00;
    }
}

But when I click validate in the Geoserver's New Style page, I gives me the following error:

Invalid input ')', expected NameCharacter, OptionalWhiteSpace or Colon (line 4, column 37)

What's the correct way to call that function, or any other WPS function?

Answer 1

The CSS syntax does not allow to use functions with a colon in the middle of the name. Instead of building it as a WPS process, built it as a filter function instead, and you'll be able to give it a simple name callable by CSS.

See: http://docs.geotools.org/latest/userguide/tutorial/function.html