fix WMS getMap unhandled exception

web/client/components/map/openlayers/plugins/WMSLayer.js

@@ -29,7 +29,7 @@ import VectorTileSource from 'ol/source/VectorTile';
 import VectorTileLayer from 'ol/layer/VectorTile';
 
 import { isVectorFormat } from '../../../../utils/VectorTileUtils';
-import { isValidResponse } from '../../../../utils/WMSUtils';
+import { isValidResponse, parseOGCException } from '../../../../utils/WMSUtils';
 import { OL_VECTOR_FORMATS, applyStyle } from '../../../../utils/openlayers/VectorTileUtils';
 
 import { proxySource, getWMSURLs, wmsToOpenlayersOptions, toOLAttributions, generateTileGrid } from '../../../../utils/openlayers/WMSUtils';
@@ -66,26 +66,25 @@ const loadFunction = (options, headers) => function(image, src) {
                 }
             }
         }).catch(e => {
+            image.setState(3);
             console.error(e);
         });
     } else {
-        if (headers) {
+        if (headers) { // case of custom headers is setted in localConfig, example requestsConfigurationRules
             axios.get(newSrc, {
                 headers,
                 responseType: 'blob'
-            }).then(response => {
-                if (isValidResponse(response)) {
+            }).then(async response => {
+                if (isValidResponse(response)) { // not contains OGC exception
                     image.getImage().src = URL.createObjectURL(response.data);
                 } else {
-                    // #10701 this is needed to trigger the imageloaderror event
-                    // in ol otherwise this event is not triggered if you assign
-                    // the xml content of the exception to the src attribute
-                    image.getImage().src = null;
-                    console.error("error: " + response.data);
+                    const exception = await parseOGCException(response);
+                    throw new Error('response exception: ' + exception);
                 }
             }).catch(e => {
-                image.getImage().src = null;
-                console.error(e);
+                image.getImage().src = null; // needed to trigger the MS imageloaderror event in Map.onLayerError
+                image.setState(3); // set error state for tile and removed from the queue and will block, prevent reloading loops
+                console.error(e);  // show ogc exception in console for debugging
             });
         } else {
             img.src = newSrc;

web/client/utils/WMSUtils.js

@@ -59,6 +59,35 @@ export const isValidResponse = (response) => {
     return response?.status === 200 && response?.data && response?.data?.type !== "text/xml";
 };
 
+/**
+ * parse the xml exception message and code
+ * @param {Object} response is axios response object containing the exception in the data property is a Blob of type text/xml
+ * @returns {string} parsed exception with code and message
+ */
+export const parseOGCException = (response) => {
+    return new Promise((resolve, reject) => {
+        const textDecoder = new TextDecoder();
+        const reader = response.data.stream().getReader();
+        reader.read().then(({ done, value }) => {
+            if (done) {
+                reject("No data available");
+                return;
+            }
+            const responseText = textDecoder.decode(value);
+            const parser = new DOMParser();
+            const xmlDoc = parser.parseFromString(responseText, "text/xml");
+            const serviceException = xmlDoc.getElementsByTagName("ServiceException")[0];
+            if (serviceException) {
+                const code = serviceException.getAttribute("code") || "unknown";
+                const message = serviceException.textContent || "unknown";
+                resolve(`code: ${code}, message: ${message}`);
+            } else {
+                resolve(`code: unknown, message: ${responseText}`);
+            }
+        }).catch(reject);
+    });
+};
+
 /**
  * Parses layer info from capabilities object
  * @param {object} capabilities capabilities section of the layer as an object from xml2js parsing of the WMS capabilities

web/client/utils/__tests__/WMSUtils-test.js

@@ -13,7 +13,8 @@ import {
     getLayerOptions,
     getTileGridFromLayerOptions,
     getCustomTileGridProperties,
-    isValidResponse
+    isValidResponse,
+    parseOGCException
 } from '../WMSUtils';
 
 describe('Test the WMSUtils', () => {
@@ -132,4 +133,16 @@ describe('Test the WMSUtils', () => {
         // valid responses
         expect(isValidResponse({data: {type: "blob"}, status: 200})).toBeTruthy();
     });
+    it('test parseOGCException', () => {
+        const response = {
+            data: new Blob([`<?xml version="1.0" encoding="UTF-8"?><ServiceExceptionReport version="1.3.0" xmlns="http://www.opengis.net/ogc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/ogc https://geoserver-d.eugeadev.iasp.tgscloud.net/geoserver/schemas/wms/1.3.0/exceptions_1_3_0.xsd"><ServiceException code="internalError">Rendering process failed. Layers: road_issue:Road</ServiceException></ServiceExceptionReport>`], { type: 'text/xml' }),
+            status: 200
+        };
+        expect(parseOGCException(response).then((result) => {
+            expect(result).toEqual({
+                code: 'internalError',
+                message: 'Rendering process failed. Layers: road_issue:Road'
+            });
+        }));
+    });
 });