move spring, servlet, filter etc init to WebApplicationInitializer

Author: goekay

src/main/java/de/rwth/idsg/steve/SteveAppContext.java

@@ -18,13 +18,10 @@
  */
 package de.rwth.idsg.steve;
 
-import org.apache.cxf.transport.servlet.CXFServlet;
 import org.apache.tomcat.InstanceManager;
 import org.apache.tomcat.SimpleInstanceManager;
 import org.eclipse.jetty.ee10.apache.jsp.JettyJasperInitializer;
-import org.eclipse.jetty.ee10.servlet.FilterHolder;
 import org.eclipse.jetty.ee10.servlet.ServletContextHandler;
-import org.eclipse.jetty.ee10.servlet.ServletHolder;
 import org.eclipse.jetty.ee10.webapp.WebAppContext;
 import org.eclipse.jetty.rewrite.handler.RedirectPatternRule;
 import org.eclipse.jetty.rewrite.handler.RewriteHandler;
@@ -34,16 +31,8 @@
 import org.eclipse.jetty.server.handler.gzip.GzipHandler;
 import org.eclipse.jetty.util.component.AbstractLifeCycle;
 import org.springframework.core.io.ClassPathResource;
-import org.springframework.security.web.context.AbstractSecurityWebApplicationInitializer;
-import org.springframework.web.context.ContextLoaderListener;
-import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
-import org.springframework.web.filter.DelegatingFilterProxy;
-import org.springframework.web.servlet.DispatcherServlet;
-
-import jakarta.servlet.DispatcherType;
 
 import java.io.IOException;
-import java.util.EnumSet;
 import java.util.HashSet;
 
 import static de.rwth.idsg.steve.SteveConfiguration.CONFIG;
@@ -54,13 +43,33 @@
  */
 public class SteveAppContext {
 
-    private final AnnotationConfigWebApplicationContext springContext;
+    // scan all jars in the classpath for ServletContainerInitializers
+    // (e.g. Spring's WebApplicationInitializer)
+    private static final String SCAN_PATTERN = ".*\\.jar$|.*/classes/.*";
+
     private final WebAppContext webAppContext;
 
     public SteveAppContext() {
-        springContext = new AnnotationConfigWebApplicationContext();
-        springContext.scan("de.rwth.idsg.steve.config");
-        webAppContext = initWebApp();
+        webAppContext = new WebAppContext();
+        webAppContext.setContextPath(CONFIG.getContextPath());
+        webAppContext.setBaseResourceAsString(getWebAppURIAsString());
+
+        // if during startup an exception happens, do not swallow it, throw it
+        webAppContext.setThrowUnavailableOnStartupException(true);
+
+        // Disable directory listings if no index.html is found.
+        webAppContext.setInitParameter("org.eclipse.jetty.servlet.Default.dirAllowed", "false");
+
+        // Crucial for Spring's WebApplicationInitializer to be discovered
+        // and for the DispatcherServlet to be initialized.
+        // It tells Jetty to scan for classes implementing WebApplicationInitializer.
+        // The pattern ensures that Jetty finds the Spring classes in the classpath.
+        //
+        // https://jetty.org/docs/jetty/12.1/programming-guide/maven-jetty/jetty-maven-plugin.html
+        // https://jetty.org/docs/jetty/12.1/operations-guide/annotations/index.html#og-container-include-jar-pattern
+        webAppContext.setAttribute("org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern", SCAN_PATTERN);
+
+        initJSP(webAppContext);
     }
 
     public ContextHandlerCollection getHandlers() {
@@ -80,36 +89,6 @@ private Handler getWebApp() {
         return new GzipHandler(webAppContext);
     }
 
-    private WebAppContext initWebApp() {
-        WebAppContext ctx = new WebAppContext();
-        ctx.setContextPath(CONFIG.getContextPath());
-        ctx.setBaseResourceAsString(getWebAppURIAsString());
-
-        // if during startup an exception happens, do not swallow it, throw it
-        ctx.setThrowUnavailableOnStartupException(true);
-
-        // Disable directory listings if no index.html is found.
-        ctx.setInitParameter("org.eclipse.jetty.servlet.Default.dirAllowed", "false");
-
-        ServletHolder web = new ServletHolder("spring-dispatcher", new DispatcherServlet(springContext));
-        ServletHolder cxf = new ServletHolder("cxf", new CXFServlet());
-
-        ctx.addEventListener(new ContextLoaderListener(springContext));
-        ctx.addServlet(web, CONFIG.getSpringMapping());
-        ctx.addServlet(cxf, CONFIG.getCxfMapping() + "/*");
-
-        // add spring security
-        ctx.addFilter(
-            // The bean name is not arbitrary, but is as expected by Spring
-            new FilterHolder(new DelegatingFilterProxy(AbstractSecurityWebApplicationInitializer.DEFAULT_FILTER_NAME)),
-            CONFIG.getSpringMapping() + "*",
-            EnumSet.allOf(DispatcherType.class)
-        );
-
-        initJSP(ctx);
-        return ctx;
-    }
-
     private Handler getRedirectHandler() {
         RewriteHandler rewrite = new RewriteHandler();
         for (String redirect : getRedirectSet()) {

src/main/java/de/rwth/idsg/steve/config/WebConfig.java

@@ -0,0 +1,71 @@
+/*
+ * SteVe - SteckdosenVerwaltung - https://github.com/steve-community/steve
+ * Copyright (C) 2013-2025 SteVe Community Team
+ * All Rights Reserved.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package de.rwth.idsg.steve.config;
+
+import lombok.extern.slf4j.Slf4j;
+import org.apache.cxf.transport.servlet.CXFServlet;
+import org.springframework.security.web.context.AbstractSecurityWebApplicationInitializer;
+import org.springframework.web.WebApplicationInitializer;
+import org.springframework.web.context.ContextLoaderListener;
+import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
+import org.springframework.web.servlet.DispatcherServlet;
+
+import jakarta.servlet.DispatcherType;
+import jakarta.servlet.ServletContext;
+import jakarta.servlet.ServletException;
+
+import java.util.EnumSet;
+
+import static de.rwth.idsg.steve.SteveConfiguration.CONFIG;
+
+/**
+ * Jetty will automatically detect this class because of {@link de.rwth.idsg.steve.SteveAppContext#SCAN_PATTERN} and
+ * use it to initialize the Spring and servlets and filters.
+ *
+ * @author Sevket Goekay <[email protected]>
+ * @since 17.09.2025
+ */
+@Slf4j
+public class WebConfig implements WebApplicationInitializer {
+
+    @Override
+    public void onStartup(ServletContext servletContext) throws ServletException {
+        log.info("Initializing");
+
+        // Spring root context
+        AnnotationConfigWebApplicationContext springContext = new AnnotationConfigWebApplicationContext();
+        springContext.scan("de.rwth.idsg.steve.config");
+        servletContext.addListener(new ContextLoaderListener(springContext));
+
+        // Spring MVC
+        var dispatcher = servletContext.addServlet("spring-dispatcher", new DispatcherServlet(springContext));
+        dispatcher.setLoadOnStartup(1);
+        dispatcher.addMapping(CONFIG.getSpringMapping());
+
+        // Apache CXF
+        var cxf = servletContext.addServlet("cxf", new CXFServlet());
+        cxf.setLoadOnStartup(1);
+        cxf.addMapping(CONFIG.getCxfMapping() + "/*");
+
+        // add spring security
+        servletContext
+            .addFilter(AbstractSecurityWebApplicationInitializer.DEFAULT_FILTER_NAME, "org.springframework.web.filter.DelegatingFilterProxy")
+            .addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), true, CONFIG.getSpringMapping() + "*");
+    }
+}