Allow parameter filters to be private and not exposed in capabilities OL preview and the like (#1545)

Author: aaime

geowebcache/core/src/main/java/org/geowebcache/demo/Demo.java

@@ -406,6 +406,9 @@ private static String makeModifiableParameters(TileLayer tl) {
         doc.append("<table>\n");
         for (ParameterFilter pf : parameterFilters) {
             Assert.notNull(pf, "The parameter filter must be non null");
+            if (!pf.isUserVisible()) {
+                continue;
+            }
             String key = pf.getKey();
             String defaultValue = pf.getDefaultValue();
             List<String> legalValues = pf.getLegalValues();

geowebcache/core/src/main/java/org/geowebcache/filter/parameters/ParameterFilter.java

@@ -56,6 +56,17 @@ public String getKey() {
         return key;
     }
 
+    /**
+     * Whether this filter should be shown to clients in user-facing surfaces (preview, seed form, WMS/WMTS
+     * capabilities). Synthetic filters that exist only to partition the cache should return {@code false} so they stay
+     * out of those surfaces while still taking part in cache key computation. One example of such a parameter is an
+     * internal filter matching the current security setup, or whatever other machinery might change the contents of a
+     * tile (e.g., a dispatcher callback clipping rasters as a home-grown security system).
+     */
+    public boolean isUserVisible() {
+        return true;
+    }
+
     /** Get the default value to use if the parameter is not specified. */
     public String getDefaultValue() {
         if (defaultValue == null) return "";

geowebcache/rest/src/main/java/org/geowebcache/rest/service/FormService.java

@@ -337,6 +337,9 @@ private void makeModifiableParameters(StringBuilder doc, TileLayer tl) {
         doc.append("<table>");
         for (ParameterFilter pf : parameterFilters) {
             Assert.notNull(pf, "Parameter filter must be non null");
+            if (!pf.isUserVisible()) {
+                continue;
+            }
             String key = pf.getKey();
             String defaultValue = pf.getDefaultValue();
             List<String> legalValues = pf.getLegalValues();

geowebcache/wms/src/main/java/org/geowebcache/service/wms/WMSGetCapabilities.java

@@ -542,6 +542,9 @@ private void capabilityLayerInner(XMLBuilder xml, TileLayer layer) throws GeoWeb
             StringBuilder dims = new StringBuilder();
             StringBuilder extents = new StringBuilder();
             for (ParameterFilter parameterFilter : layer.getParameterFilters()) {
+                if (!parameterFilter.isUserVisible()) {
+                    continue;
+                }
                 if (parameterFilter instanceof WMSDimensionProvider provider) {
                     provider.appendDimensionElement(dims, "      ");
                     provider.appendExtentElement(extents, "      ");

geowebcache/wmts/src/main/java/org/geowebcache/service/wmts/WMTSGetCapabilities.java

@@ -470,8 +470,11 @@ private void layer(XMLBuilder xml, TileLayer layer, String baseurl, Set<GridSet>
             }
         }
 
-        // We need the filters for styles and dimensions
+        // We need the filters for styles and dimensions; drop synthetic, non user-visible ones (e.g. security)
         List<ParameterFilter> filters = layer.getParameterFilters();
+        if (filters != null) {
+            filters = filters.stream().filter(ParameterFilter::isUserVisible).toList();
+        }
 
         layerStyles(xml, layer, filters);
 

geowebcache/wmts/src/test/java/org/geowebcache/service/wmts/WMTSServiceTest.java

@@ -755,6 +755,7 @@ public void testGetCapUnboundedStyleFilter() throws Exception {
             List<String> gridSetNames = Arrays.asList("GlobalCRS84Pixel", "GlobalCRS84Scale", "EPSG:4326");
 
             ParameterFilter styleFilter = mock(ParameterFilter.class);
+            when(styleFilter.isUserVisible()).thenReturn(true);
             when(styleFilter.getKey()).thenReturn("STYLES");
             when(styleFilter.getDefaultValue()).thenReturn("Foo");
             when(styleFilter.getLegalValues()).thenReturn(null);
@@ -813,6 +814,7 @@ public void testGetCapEmptyStyleFilter() throws Exception {
             List<String> gridSetNames = Arrays.asList("GlobalCRS84Pixel", "GlobalCRS84Scale", "EPSG:4326");
 
             ParameterFilter styleFilter = mock(ParameterFilter.class);
+            when(styleFilter.isUserVisible()).thenReturn(true);
             when(styleFilter.getKey()).thenReturn("STYLES");
             when(styleFilter.getDefaultValue()).thenReturn("Foo");
             when(styleFilter.getLegalValues()).thenReturn(Collections.emptyList());
@@ -871,6 +873,7 @@ public void testGetCapMultipleStyles() throws Exception {
             List<String> gridSetNames = Arrays.asList("GlobalCRS84Pixel", "GlobalCRS84Scale", "EPSG:4326");
 
             ParameterFilter styleFilter = mock(ParameterFilter.class);
+            when(styleFilter.isUserVisible()).thenReturn(true);
             when(styleFilter.getKey()).thenReturn("STYLES");
             when(styleFilter.getDefaultValue()).thenReturn("Foo");
             when(styleFilter.getLegalValues()).thenReturn(Arrays.asList("Foo", "Bar", "Baz"));
@@ -972,16 +975,19 @@ public void testGetCapWithMultipleDimensions() throws Exception {
             List<String> gridSetNames = Arrays.asList("GlobalCRS84Pixel", "GlobalCRS84Scale", "EPSG:4326");
 
             ParameterFilter styleFilter = mock(ParameterFilter.class);
+            when(styleFilter.isUserVisible()).thenReturn(true);
             when(styleFilter.getKey()).thenReturn("STYLES");
             when(styleFilter.getDefaultValue()).thenReturn("Foo");
             when(styleFilter.getLegalValues()).thenReturn(Arrays.asList("Foo", "Bar", "Baz"));
 
             ParameterFilter elevationDimension = mock(ParameterFilter.class);
+            when(elevationDimension.isUserVisible()).thenReturn(true);
             when(elevationDimension.getKey()).thenReturn("elevation");
             when(elevationDimension.getDefaultValue()).thenReturn("0");
             when(elevationDimension.getLegalValues()).thenReturn(Arrays.asList("0", "200", "400", "600"));
 
             ParameterFilter timeDimension = mock(ParameterFilter.class);
+            when(timeDimension.isUserVisible()).thenReturn(true);
             when(timeDimension.getKey()).thenReturn("time");
             when(timeDimension.getDefaultValue()).thenReturn("2016-02-23T03:00:00.00");
             when(timeDimension.getLegalValues()).thenReturn(Collections.emptyList());
@@ -1049,6 +1055,7 @@ public void testGetTileWithStyle() throws Exception {
             List<String> gridSetNames = Arrays.asList("GlobalCRS84Pixel", "GlobalCRS84Scale", "EPSG:4326");
 
             ParameterFilter styleFilter = mock(ParameterFilter.class);
+            when(styleFilter.isUserVisible()).thenReturn(true);
             when(styleFilter.getKey()).thenReturn("STYLES");
             when(styleFilter.getDefaultValue()).thenReturn("Foo");
             when(styleFilter.getLegalValues()).thenReturn(Arrays.asList("Foo", "Bar", "Baz"));