How to specify a fallback font for a GeoServer style

Question

I am trying to add place names to a map with GeoServer. This works as expected, except that I am unable to add a fallback font family. When I try to add one, the displayed names use a serif font, suggesting that the font family information is being ignored entirely. This is a code snippet:

<sld:TextSymbolizer>
            <sld:Label>
              <ogc:PropertyName>name</ogc:PropertyName>
            </sld:Label>
            <sld:Font>
              <sld:CssParameter name="font-family">Noto Sans</sld:CssParameter>
              <sld:CssParameter name="font-size">34</sld:CssParameter>
            </sld:Font>
            <sld:LabelPlacement>
              <sld:PointPlacement>
                <sld:AnchorPoint>
                  <sld:AnchorPointX>0.5</sld:AnchorPointX>
                  <sld:AnchorPointY>1</sld:AnchorPointY>
                </sld:AnchorPoint>
                <sld:Displacement>
                  <sld:DisplacementX>0</sld:DisplacementX>
                  <sld:DisplacementY>-7</sld:DisplacementY>
                </sld:Displacement>
              </sld:PointPlacement>
            </sld:LabelPlacement>

            <Halo>
              <Radius>1.5</Radius>
              <Fill>
                <CssParameter name="fill">#FFFFFF</CssParameter>
                <CssParameter name="fill-opacity">0.75</CssParameter>
              </Fill>
            </Halo>

            <sld:Fill>
              <sld:CssParameter name="fill">#000000</sld:CssParameter>
            </sld:Fill>
            <sld:Priority>
              <ogc:Sub>
                <ogc:Literal>100</ogc:Literal>
                <ogc:PropertyName>labelrank</ogc:PropertyName>
              </ogc:Sub>
            </sld:Priority>


            <sld:VendorOption name="conflictResolution">true</sld:VendorOption>
            <sld:VendorOption name="maxDisplacement">18</sld:VendorOption>
            <sld:VendorOption name="spaceAround">6</sld:VendorOption>
            <sld:VendorOption name="autoWrap">60</sld:VendorOption>
          </sld:TextSymbolizer>

I have successfully installed both Lato and Noto Sans, and using either of these individually works as expected. But if I try something like the following I get neither (and instead just a system serif font), e.g.

<sld:CssParameter name="font-family">Lato, Noto Sans</sld:CssParameter>

How can I correctly specify a fallback font family?

I'm using GeoServer vn 2.25.3

Answer 1

You can just list all the font families one after the other:

  <CssParameter name="font-family">Cantarell Light</CssParameter>
  <CssParameter name="font-family">Times New Roman</CssParameter>

GeoServer will pick the first it recognises.