feat: Make RequestUtil#getUrlMapping public for manual security configuration (#22446)

* Initial plan

* Make RequestUtil#getUrlMapping public method with documentation and tests

Co-authored-by: mshabarov <61410877+mshabarov@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: mshabarov <61410877+mshabarov@users.noreply.github.com>
Co-authored-by: Teppo Kurki <teppo.kurki@vaadin.com>

Author: 3 people

vaadin-spring/src/main/java/com/vaadin/flow/spring/security/RequestUtil.java

@@ -393,7 +393,13 @@ private String getRequestRoutePath(HttpServletRequest request) {
                 .orElse(null);
     }
 
-    String getUrlMapping() {
+    /**
+     * Gets the url mapping for the Vaadin servlet.
+     *
+     * @return the url mapping
+     * @see VaadinConfigurationProperties#getUrlMapping()
+     */
+    public String getUrlMapping() {
         return configurationProperties.getUrlMapping();
     }
 

vaadin-spring/src/test/java/com/vaadin/flow/spring/security/RequestUtilTest.java

@@ -656,4 +656,25 @@ static MockHttpServletRequest createRequest(String pathInfo,
         return r;
     }
 
+    @Test
+    public void testGetUrlMapping_fooMappedServlet_returnsMappingValue() {
+        Mockito.when(vaadinConfigurationProperties.getUrlMapping())
+                .thenReturn("/foo/*");
+        Assert.assertEquals("/foo/*", requestUtil.getUrlMapping());
+    }
+
+    @Test
+    public void testGetUrlMapping_rootMappedServlet_returnsMappingValue() {
+        Mockito.when(vaadinConfigurationProperties.getUrlMapping())
+                .thenReturn("/*");
+        Assert.assertEquals("/*", requestUtil.getUrlMapping());
+    }
+
+    @Test
+    public void testGetUrlMapping_nullMapping_returnsNull() {
+        Mockito.when(vaadinConfigurationProperties.getUrlMapping())
+                .thenReturn(null);
+        Assert.assertNull(requestUtil.getUrlMapping());
+    }
+
 }