Supporting TCRS configuration through gridset selector

doc/en/user/source/extensions/mapml/installation.rst

@@ -47,6 +47,33 @@ If the ``Represent multi-layer requests as multiple elements`` is checked (and t
 
 .. figure:: images/mapml_wms_multi_extent.png
 
+TiledCRS
+--------
+MapML supports 4 built-in TiledCRS:
+
+- MapML:WGS84 (or EPSG:4326)
+- MapML:OSMTILE (or EPSG:3857)
+- MapML:CBMTILE (or EPSG:3978)
+- MapML:APSTILE (or EPSG:5936)
+
+In addition, is it possible to configure custom TiledCRS based on the available WMTS GridSets.
+A new MapML TCRS Settings menu is available in the GeoServer UI on the Settings section:
+
+.. figure:: images/mapml_tcrs_menu.png
+
+
+It provides a selector containing available GridSets. Administrator can select GridSets from the left list that will be converted to TiledCRSs.
+
+
+.. figure:: images/mapml_tcrs_selector.png
+
+
+Notes:
+
+- Gridsets containing ":" character in the name won't be listed
+- Gridsets with not-numeric levels or without a common prefix won't be listed
+
+
 Styles
 ------
 
@@ -262,7 +289,7 @@ MapML resources will be available for any published WMS layers by making a GetMa
 
 **SRS/CRS**
 
-Note that the WMS SRS or CRS must be one of the projections supported by MapML:
+Note that the WMS SRS or CRS must be one of the built-in projections supported by MapML or one of the TCRS configured through the dedicated section. Built-in MapML CRS are:
 
 - MapML:WGS84 (or EPSG:4326)
 - MapML:OSMTILE (or EPSG:3857)

src/extension/mapml/src/main/java/org/geoserver/mapml/MapMLFeatureUtil.java

@@ -37,15 +37,13 @@
 import org.geoserver.mapml.xml.Link;
 import org.geoserver.mapml.xml.Mapml;
 import org.geoserver.mapml.xml.Meta;
-import org.geoserver.mapml.xml.ProjType;
 import org.geoserver.mapml.xml.RelType;
 import org.geoserver.ows.Request;
 import org.geoserver.ows.URLMangler;
 import org.geoserver.ows.util.ResponseUtils;
 import org.geoserver.platform.ServiceException;
 import org.geoserver.wms.featureinfo.FeatureTemplate;
 import org.geotools.api.feature.simple.SimpleFeature;
-import org.geotools.api.referencing.FactoryException;
 import org.geotools.api.referencing.crs.CoordinateReferenceSystem;
 import org.geotools.api.referencing.crs.GeodeticCRS;
 import org.geotools.api.style.Style;
@@ -409,7 +407,7 @@ private static Set<Meta> deduceProjectionAndExtent(
             if (requestCRS != null) {
                 responseCRS = requestCRS;
                 responseCRSCode = CRS.toSRS(requestCRS);
-                tcrs = TiledCRSConstants.lookupTCRS(responseCRSCode);
+                tcrs = TiledCRSConstants.lookupTCRSParams(responseCRSCode);
                 if (tcrs != null) {
                     projection.setContent(tcrs.getName());
                     crs = (responseCRS instanceof GeodeticCRS) ? "gcrs" : "pcrs";
@@ -453,7 +451,7 @@ private static String getExtent(
                 "top-left-easting=%1$.2f,top-left-northing=%2$.2f,bottom-right-easting=%3$.2f,bottom-right-northing=%4$.2f";
         double minLong, minLat, maxLong, maxLat;
         double minEasting, minNorthing, maxEasting, maxNorthing;
-        TiledCRSParams tcrs = TiledCRSConstants.lookupTCRS(responseCRSCode);
+        TiledCRSParams tcrs = TiledCRSConstants.lookupTCRSParams(responseCRSCode);
         try {
             if (responseCRS instanceof GeodeticCRS) {
                 re = r.getLatLonBoundingBox();
@@ -506,30 +504,27 @@ public static List<Link> alternateProjections(
             String base, String path, Map<String, Object> query) {
         ArrayList<Link> links = new ArrayList<>();
         Set<String> projections = TiledCRSConstants.tiledCRSBySrsName.keySet();
-        projections.forEach(
-                (String p) -> {
-                    Link l = new Link();
-                    TiledCRSParams projection = TiledCRSConstants.lookupTCRS(p);
-                    try {
-                        l.setProjection(ProjType.fromValue(projection.getName()));
-                    } catch (FactoryException e) {
-                        throw new ServiceException("Invalid TCRS name");
-                    }
-                    l.setRel(RelType.ALTERNATE);
-                    query.put("srsName", "MapML:" + projection.getName());
-                    HashMap<String, String> kvp = new HashMap<>(query.size());
-                    query.keySet()
-                            .forEach(
-                                    key -> {
-                                        kvp.put(key, query.getOrDefault(key, "").toString());
-                                    });
-                    l.setHref(
-                            ResponseUtils.urlDecode(
-                                    ResponseUtils.buildURL(
-                                            base, path, kvp, URLMangler.URLType.SERVICE)));
-                    links.add(l);
-                });
-
+        for (String proj : projections) {
+            Link l = new Link();
+            TiledCRSParams projection = TiledCRSConstants.lookupTCRSParams(proj);
+            boolean addMe = false;
+            l.setProjection(projection.getName());
+            addMe = true;
+
+            if (!addMe) continue;
+            l.setRel(RelType.ALTERNATE);
+            query.put("srsName", "MapML:" + projection.getName());
+            HashMap<String, String> kvp = new HashMap<>(query.size());
+            query.keySet()
+                    .forEach(
+                            key -> {
+                                kvp.put(key, query.getOrDefault(key, "").toString());
+                            });
+            l.setHref(
+                    ResponseUtils.urlDecode(
+                            ResponseUtils.buildURL(base, path, kvp, URLMangler.URLType.SERVICE)));
+            links.add(l);
+        }
         return links;
     }
 

src/extension/mapml/src/main/java/org/geoserver/mapml/MapMLHTMLGetFeatureOutputFormat.java

@@ -20,7 +20,7 @@
 import javax.servlet.http.HttpServletRequest;
 import org.geoserver.catalog.LayerInfo;
 import org.geoserver.config.GeoServer;
-import org.geoserver.mapml.xml.ProjType;
+import org.geoserver.mapml.tcrs.WrappingProjType;
 import org.geoserver.ows.Dispatcher;
 import org.geoserver.ows.Request;
 import org.geoserver.ows.URLMangler;
@@ -83,7 +83,7 @@ protected void write(
         ReferencedEnvelope projectedBbox = extractBbox(fc);
         LayerInfo layerInfo = gs.getCatalog().getLayerByName(fc.getSchema().getTypeName());
         CoordinateReferenceSystem crs = projectedBbox.getCoordinateReferenceSystem();
-        ProjType projType = parseProjType(request);
+        WrappingProjType projType = parseProjType(request);
         double longitude;
         double latitude;
         ReferencedEnvelope geographicBox;
@@ -116,7 +116,7 @@ protected void write(
         osw.flush();
     }
 
-    private ProjType parseProjType(Request request) throws ServiceException {
+    private WrappingProjType parseProjType(Request request) throws ServiceException {
         try {
             Map<String, Object> rawKvp = request.getRawKvp();
             String srs;
@@ -127,7 +127,7 @@ private ProjType parseProjType(Request request) throws ServiceException {
             } else {
                 srs = "EPSG:4326";
             }
-            return ProjType.fromValue(srs.toUpperCase());
+            return new WrappingProjType(srs.toUpperCase());
         } catch (IllegalArgumentException | FactoryException iae) {
             // figure out the parameter name (version dependent) and the actual original
             // string value for the srs/crs parameter

src/extension/mapml/src/main/java/org/geoserver/mapml/MapMLHTMLOutput.java

@@ -6,32 +6,26 @@
 
 import static org.apache.commons.text.StringEscapeUtils.escapeHtml4;
 
-import java.util.HashMap;
+import java.util.Locale;
 import javax.servlet.http.HttpServletRequest;
 import org.geoserver.mapml.tcrs.Bounds;
 import org.geoserver.mapml.tcrs.Point;
 import org.geoserver.mapml.tcrs.TiledCRS;
-import org.geoserver.mapml.xml.ProjType;
+import org.geoserver.mapml.tcrs.TiledCRSParams;
+import org.geoserver.mapml.tcrs.WrappingProjType;
 import org.geoserver.ows.URLMangler;
 import org.geoserver.ows.util.ResponseUtils;
+import org.geotools.api.referencing.crs.CoordinateReferenceSystem;
 import org.geotools.geometry.jts.ReferencedEnvelope;
 import org.geotools.referencing.CRS;
+import org.geotools.referencing.proj.PROJFormatter;
 
 /** Class delegated to build an HTML Document embedding a MapML Viewer. */
 public class MapMLHTMLOutput {
 
-    public static final HashMap<String, TiledCRS> PREVIEW_TCRS_MAP = new HashMap<>();
-
-    static {
-        PREVIEW_TCRS_MAP.put("OSMTILE", new TiledCRS("OSMTILE"));
-        PREVIEW_TCRS_MAP.put("CBMTILE", new TiledCRS("CBMTILE"));
-        PREVIEW_TCRS_MAP.put("APSTILE", new TiledCRS("APSTILE"));
-        PREVIEW_TCRS_MAP.put("WGS84", new TiledCRS("WGS84"));
-    }
-
     private String layerLabel;
     private HttpServletRequest request;
-    private ProjType projType;
+    private WrappingProjType projType;
     private String sourceUrL;
     private int zoom = 0;
     private Double latitude = 0.0;
@@ -54,7 +48,7 @@ private MapMLHTMLOutput(HTMLOutputBuilder builder) {
     public static class HTMLOutputBuilder {
         private String layerLabel;
         private HttpServletRequest request;
-        private ProjType projType;
+        private WrappingProjType projType;
         private String sourceUrL;
         private ReferencedEnvelope projectedBbox;
         private int zoom = 0;
@@ -72,7 +66,7 @@ public HTMLOutputBuilder setRequest(HttpServletRequest request) {
             return this;
         }
 
-        public HTMLOutputBuilder setProjType(ProjType projType) {
+        public HTMLOutputBuilder setProjType(WrappingProjType projType) {
             this.projType = projType;
             return this;
         }
@@ -127,6 +121,7 @@ public String toHTML() {
                 .append("mapml-viewer:not(:defined) > * { display: none; } n")
                 .append("map-layer { display: none; }\n")
                 .append("</style>\n")
+                .append(buildProjectionScript(projType))
                 .append("<noscript>\n")
                 .append("<style>\n")
                 .append("mapml-viewer:not(:defined) > :not(map-layer) { display: initial; }\n")
@@ -136,7 +131,7 @@ public String toHTML() {
                 .append("</head>\n")
                 .append("<body>\n")
                 .append("<mapml-viewer projection=\"")
-                .append(projType.value())
+                .append(projType.getTiledCRS().getParams().getName())
                 .append("\" ")
                 .append("zoom=\"")
                 .append(computeZoom(projType, projectedBbox))
@@ -158,14 +153,91 @@ public String toHTML() {
         return sb.toString();
     }
 
+    private String buildProjectionScript(WrappingProjType projType) {
+        String projectionScript = "";
+        if (!projType.isBuiltIn()) {
+            StringBuilder sb = new StringBuilder();
+            sb.append("<script type=\"module\">\n")
+                    .append("let customProjectionDefinition = `\n")
+                    .append(buildDefinition(projType.getTiledCRS(), 10))
+                    .append("let map = document.querySelector(\"mapml-viewer\");\n")
+                    .append(
+                            "let cProjection = map.defineCustomProjection(customProjectionDefinition);\n")
+                    .append("map.projection = cProjection;\n")
+                    .append("</script>");
+            projectionScript = sb.toString();
+        }
+        return projectionScript;
+    }
+
+    private String buildDefinition(TiledCRS tiledCRS, int indentChars) {
+        TiledCRSParams params = tiledCRS.getParams();
+        int tileSize = params.getTILE_SIZE();
+        String name = params.getName();
+        Point origin = params.getOrigin();
+        String indent = " ".repeat(indentChars);
+        String originString = String.format("[%.8f, %.8f]", origin.getX(), origin.getY());
+
+        double[] resolutions = params.getResolutions();
+        StringBuilder resolutionsString = new StringBuilder("[");
+        for (int i = 0; i < resolutions.length; i++) {
+            resolutionsString.append(resolutions[i]);
+            if (i != resolutions.length - 1) {
+                resolutionsString.append(", ");
+            }
+        }
+        resolutionsString.append("]");
+
+        Bounds bounds = params.getBounds();
+        String boundsString =
+                String.format(
+                        Locale.ENGLISH,
+                        "[[%.8f, %.8f], [%.8f, %.8f]]",
+                        bounds.getMin().getX(),
+                        bounds.getMin().getY(),
+                        bounds.getMax().getX(),
+                        bounds.getMax().getY());
+
+        CoordinateReferenceSystem crs = tiledCRS.getCRS();
+        PROJFormatter formatter = new PROJFormatter();
+        String projString = formatter.toPROJ(crs);
+        StringBuilder sb =
+                new StringBuilder("{\n")
+                        .append("\"projection\": \"")
+                        .append(name)
+                        .append("\",\n")
+                        .append(indent)
+                        .append("\"origin\": ")
+                        .append(originString)
+                        .append(",\n")
+                        .append(indent)
+                        .append("\"resolutions\": ")
+                        .append(resolutionsString)
+                        .append(",\n")
+                        .append(indent)
+                        .append("\"bounds\": ")
+                        .append(boundsString)
+                        .append(",\n")
+                        .append(indent)
+                        .append("\"tilesize\": ")
+                        .append(tileSize)
+                        .append(",\n")
+                        .append(indent)
+                        .append("\"proj4string\" : \"")
+                        .append(projString)
+                        .append("\"\n")
+                        .append("}`;\n");
+        return sb.toString();
+    }
+
     private String buildViewerPath(HttpServletRequest request) {
         String base = ResponseUtils.baseURL(request);
         return ResponseUtils.buildURL(
                 base, "/mapml/viewer/widget/mapml.js", null, URLMangler.URLType.RESOURCE);
     }
 
-    private int computeZoom(ProjType projType, ReferencedEnvelope projectedBbox) {
-        TiledCRS tcrs = PREVIEW_TCRS_MAP.get(projType.value());
+    private int computeZoom(WrappingProjType projType, ReferencedEnvelope projectedBbox) {
+        TiledCRS tcrs = projType.getTiledCRS();
         boolean flipAxis =
                 CRS.getAxisOrder(projectedBbox.getCoordinateReferenceSystem())
                         .equals(CRS.AxisOrder.NORTH_EAST);