Geoserver - Can't get LegendGraphic of WMS in Cascade

Question

I have configured a Cascade WMS in Geoserver and published some layers of this server. The Styles are shown correctly in Client Side Openlayers. But when I look at the capabilities no Online Resource is generated, so I can't get the legend URL. Also there's no menu for styles when I try to edit those layers.

Why Openlayers is rendering the layers with the correct style if there's no style in my geoserver and the GetMap request has no style key?

http://192.168.1.14:8080/geoserver/jahr/wms?SERVICE=WMS&VERSION=1.1.0&REQUEST=GetMap&FORMAT=image%2Fpng&TRANSPARENT=true&tiled=true&LAYERS=jahr%3ACentros_Municipales&STYLES&WIDTH=256&HEIGHT=256&SRS=EPSG%3A4258&BBOX=-0.4625%2C39.42875%2C-0.43125%2C39.46

Someone had the same problem?

Answer 1

The GeoServer documentation about cascaded WMS services http://docs.geoserver.org/stable/en/user/data/cascaded/wms.html has a section "Limitations"

Layers served through an external WMS have some, but not all of the functionality of a local WMS.

• Layers cannot be styled with SLD.
• Alternate (local) styles cannot be used.
• Extra request parameters (time, elevation, cql_filter, etc.) cannot be used.
• GetLegendGraphic requests aren’t supported.
• Image format cannot be specified. GeoServer will attempt to request PNG images, and if that fails will use the remote server’s default image format.
• Authentication for the remote WMS isn’t supported. The remote WMS must be unsecured. (This part of documentation is old, you can give username/password of the remote WMS in the connection details)

You asked three questions:

1. Q: Why not GetLegendGraphics link? A: It is not supported.
2. Q: Why I can't set local styles? A: It is not supported
3. Q: Why WMS shows correct styles even I have not set any? A: The default style of the remote WMS layer is used.