refactor: Integrate dev server static resource serving with StaticFileServer (#12256)

Author: Artur-

flow-server/src/main/java/com/vaadin/flow/internal/DevModeHandler.java

@@ -25,14 +25,14 @@
 public interface DevModeHandler extends RequestHandler {
 
     /**
-     * Return webpack console output when a compilation error happened.
+     * Return the dev server console output when a compilation error happened.
      *
      * @return console output if error or null otherwise.
      */
     String getFailedOutput();
 
     /**
-     * Prepare a HTTP connection against webpack-dev-server.
+     * Prepare a HTTP connection against the dev server.
      *
      * @param path
      *            the file to request, needs to be safe
@@ -46,22 +46,22 @@ HttpURLConnection prepareConnection(String path, String method)
             throws IOException;
 
     /**
-     * Returns true if it's a request that should be handled by webpack.
+     * Returns true if it's a request that should be handled by the dev server.
      *
      * @param request
      *            the servlet request
-     * @return true if the request should be forwarded to webpack
+     * @return true if the request should be forwarded to the dev server
      */
     boolean isDevModeRequest(HttpServletRequest request);
 
     /**
-     * Serve a file by proxying to webpack.
+     * Serve a file by proxying to the dev server.
      *
      * @param request
      *            the servlet request
      * @param response
      *            the servlet response
-     * @return false if webpack returned a not found, true otherwise
+     * @return false if the dev server returned a not found, true otherwise
      * @throws IOException
      *             in the case something went wrong like connection refused
      */

flow-server/src/main/java/com/vaadin/flow/server/StaticFileServer.java

@@ -42,6 +42,8 @@
 import org.slf4j.LoggerFactory;
 
 import com.vaadin.flow.function.DeploymentConfiguration;
+import com.vaadin.flow.internal.DevModeHandler;
+import com.vaadin.flow.internal.DevModeHandlerManager;
 import com.vaadin.flow.internal.ResponseWriter;
 import com.vaadin.flow.server.frontend.FrontendUtils;
 
@@ -73,6 +75,7 @@ public class StaticFileServer implements StaticFileHandler {
     private final VaadinService vaadinService;
     private DeploymentConfiguration deploymentConfiguration;
     private final List<String> manifestPaths;
+    private DevModeHandler devModeHandler;
 
     // Matcher to match string starting with '/themes/[theme-name]/'
     public static final Pattern APP_THEME_PATTERN = Pattern
@@ -93,6 +96,9 @@ public StaticFileServer(VaadinService vaadinService) {
         deploymentConfiguration = vaadinService.getDeploymentConfiguration();
         responseWriter = new ResponseWriter(deploymentConfiguration);
         manifestPaths = getManifestPathsFromJson();
+
+        this.devModeHandler = DevModeHandlerManager
+                .getDevModeHandler(vaadinService).orElse(null);
     }
 
     @Override
@@ -107,6 +113,11 @@ public boolean isStaticResourceRequest(HttpServletRequest request) {
             return false;
         }
 
+        if (devModeHandler != null
+                && devModeHandler.isDevModeRequest(request)) {
+            return true;
+        }
+
         if (APP_THEME_PATTERN.matcher(requestFilename).find()
                 || requestFilename.startsWith("/" + VAADIN_STATIC_FILES_PATH)
                 || requestFilename.startsWith("/" + VAADIN_BUILD_FILES_PATH)) {
@@ -273,6 +284,13 @@ public boolean serveStaticResource(HttpServletRequest request,
             return true;
         }
 
+        if (devModeHandler != null
+                && devModeHandler.isDevModeRequest(request)) {
+            if (devModeHandler.serveDevModeRequest(request, response)) {
+                return true;
+            }
+        }
+
         URL resourceUrl = null;
         if (isAllowedVAADINBuildOrStaticUrl(filenameWithPath)
                 || manifestPaths.contains(filenameWithPath)) {

flow-server/src/main/java/com/vaadin/flow/server/VaadinServlet.java

@@ -25,16 +25,13 @@
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.util.Optional;
 import java.util.Properties;
 
 import com.vaadin.flow.component.UI;
 import com.vaadin.flow.di.Lookup;
 import com.vaadin.flow.function.DeploymentConfiguration;
 import com.vaadin.flow.internal.ApplicationClassLoaderAccess;
 import com.vaadin.flow.internal.CurrentInstance;
-import com.vaadin.flow.internal.DevModeHandler;
-import com.vaadin.flow.internal.DevModeHandlerManager;
 import com.vaadin.flow.internal.VaadinContextInitializer;
 import com.vaadin.flow.server.HandlerHelper.RequestType;
 import com.vaadin.flow.server.startup.ApplicationConfiguration;
@@ -331,15 +328,6 @@ protected void service(HttpServletRequest request,
     protected boolean serveStaticOrWebJarRequest(HttpServletRequest request,
             HttpServletResponse response) throws IOException {
 
-        Optional<DevModeHandler> devModeHandler = DevModeHandlerManager
-                .getDevModeHandler(getService());
-        if (devModeHandler.isPresent()
-                && devModeHandler.get().isDevModeRequest(request)
-                && devModeHandler.get().serveDevModeRequest(request,
-                        response)) {
-            return true;
-        }
-
         if (staticFileHandler.isStaticResourceRequest(request)) {
             staticFileHandler.serveStaticResource(request, response);
             return true;

flow-tests/test-dev-mode/src/test/java/com/vaadin/flow/uitest/ui/UrlValidationIT.java

@@ -39,7 +39,7 @@ public void devModeUriValidation_uriWithDirectoryChange_statusForbidden()
         waitUntil(input -> $(LabelElement.class).id("elementId").isDisplayed());
         // check the forbidden url
         sendRequestAndValidateResponseStatusForbidden(
-                "/VAADIN/build/%252E%252E/");
+                "/VAADIN/build/%252E%252E");
     }
 
     @Test

vaadin-dev-server/src/test/java/com/vaadin/base/devserver/startup/AbstractDevModeTest.java

@@ -21,6 +21,7 @@
 import com.vaadin.flow.server.Constants;
 import com.vaadin.flow.server.StaticFileHandler;
 import com.vaadin.flow.server.StaticFileHandlerFactory;
+import com.vaadin.flow.server.StaticFileServer;
 import com.vaadin.flow.server.VaadinService;
 import com.vaadin.flow.server.VaadinServletContext;
 import com.vaadin.flow.server.frontend.FrontendUtils;
@@ -85,7 +86,7 @@ public void setup() throws Exception {
         Mockito.when(lookup.lookup(ApplicationConfiguration.class))
                 .thenReturn(appConfig);
         Mockito.when(lookup.lookup(StaticFileHandlerFactory.class))
-                .thenReturn(service -> Mockito.mock(StaticFileHandler.class));
+                .thenReturn(service -> new StaticFileServer(service));
 
         vaadinService = Mockito.mock(VaadinService.class);