GWC local workspace URLs not working

[groldan]

Can't access local workspace urls for gwc (e.g. <context-path>/<workspace>/gwc/...)

[pmauduit]

reproduced / tested with the docker composition advised in the README (shared datadir), and a blank catalog. Creating a workspace / DS / layer works, I can access the following urls:

• http://localhost:9090/geoserver/cloud/gwc/demo/ns:layer?gridSet=EPSG:4326&format=image/png
• http://localhost:9090/geoserver/cloud//wms?[...]&layers=...
• http://localhost:9090/geoserver/cloud//wms?[...]&layers=:...

But indeed accessing http://localhost:9090/geoserver/cloud/<ns>/gwc/demo/<ns:layer> or http://localhost:9090/geoserver/cloud/<ns>/gwc/demo/<layer> does not.

It looks like the gateway configuration is already correct, and the issue is situated in the GWC microservice:

gwc_1        | 2024-01-09 15:57:44.375  WARN 1 --- [nio-8080-exec-7] o.s.web.servlet.PageNotFound             : No mapping for GET /geoserver/cloud/<ns>/gwc/demo/<layer>

[pmauduit]

My guess was that the controller was lacking a request path here:
https://github.com/geoserver/geoserver-cloud/blob/main/src/gwc/services/src/main/java/org/gwc/web/rest/GeoWebCacheController.java#L28

And the following beans were missing:
https://github.com/geoserver/geoserver/blob/main/src/web/gwc/src/main/java/applicationContext.xml#L97-L111

but it is still not sufficient

[pmauduit]

Digging further and comparing with a regular geoserver, I wonder if we should use a gwcDispatcher directly, or one class from the following package:
https://github.com/geoserver/geoserver/blob/main/src/gwc/src/main/java/org/geoserver/gwc/dispatch/package-info.java#L6-L37

[pmauduit]

turned out that using the geoserverDispatcher instead of the gwcDispatcher seems to make it.

[pmauduit]

We need to figure out why the gateway's base path sent as x-forwarded-path is duplicated in the getcaps responses.

Checking the WMTS GetCapabilities with my modifications, we indeed end up with duplicated path in the urls:

[...]
<ows:Operation name="GetCapabilities">
  <ows:DCP>
    <ows:HTTP>
      <ows:Get xlink:href="http://localhost:9090/geoserver/cloud/geoserver/cloud/gwc/service/wmts?">
        <ows:Constraint name="GetEncoding">
          <ows:AllowedValues>
            <ows:Value>KVP</ows:Value>
          </ows:AllowedValues>
        </ows:Constraint>
      </ows:Get>
    </ows:HTTP>
  </ows:DCP>
</ows:Operation>
[...]

In the case of the GetCapabilities, the responsible code is here:
https://github.com/GeoWebCache/geowebcache/blob/main/geowebcache/wmts/src/main/java/org/geowebcache/service/wmts/WMTSService.java#L585-L593

The urlMangler being passed to the constructor is of type org.geoserver.gwc.ResponseUtilsURLMangler, which transforms the baseUrl (https://github.com/GeoWebCache/geowebcache/blob/main/geowebcache/wmts/src/main/java/org/geowebcache/service/wmts/WMTSGetCapabilities.java#L104) to http://localhost:9090/geoserver/cloud/geoserver/cloud/gwc/service/wmts. This mangler also calls ResponseUtils.buildURL() which in turn iterates over all the URLMangler objects (https://github.com/geoserver/geoserver/blob/main/src/ows/src/main/java/org/geoserver/ows/util/ResponseUtils.java#L390-L393). Considering the gwc service from the composition, I have the following ones instanciated:

• org.geoserver.security.AuthenticationKeyMangler
• org.geoserver.ows.LocalWorkspaceURLMangler (ows = "ows")
• org.geoserver.ows.LanguageURLMangler
• org.geoserver.ows.LocalWorkspaceURLMangler (ows = "wms")
• org.geoserver.ows.LocalWorkspaceURLMangler (ows = "gwc")