Merge branch '3.2.x'

Closes gh-40322

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletComponentRegisteringPostProcessor.java

@@ -37,6 +37,8 @@
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider;
+import org.springframework.mock.web.MockServletContext;
+import org.springframework.util.ClassUtils;
 import org.springframework.web.context.WebApplicationContext;
 
 /**
@@ -50,6 +52,9 @@
 class ServletComponentRegisteringPostProcessor
 		implements BeanFactoryPostProcessor, ApplicationContextAware, BeanFactoryInitializationAotProcessor {
 
+	private static final boolean MOCK_SERVLET_CONTEXT_AVAILABLE = ClassUtils
+		.isPresent("org.springframework.mock.web.MockServletContext", null);
+
 	private static final List<ServletComponentHandler> HANDLERS;
 
 	static {
@@ -70,7 +75,7 @@ class ServletComponentRegisteringPostProcessor
 
 	@Override
 	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
-		if (isRunningInEmbeddedWebServer()) {
+		if (eligibleForServletComponentScanning()) {
 			ClassPathScanningCandidateComponentProvider componentProvider = createComponentProvider();
 			for (String packageToScan : this.packagesToScan) {
 				scanPackage(componentProvider, packageToScan);
@@ -88,9 +93,10 @@ private void scanPackage(ClassPathScanningCandidateComponentProvider componentPr
 		}
 	}
 
-	private boolean isRunningInEmbeddedWebServer() {
+	private boolean eligibleForServletComponentScanning() {
 		return this.applicationContext instanceof WebApplicationContext webApplicationContext
-				&& webApplicationContext.getServletContext() == null;
+				&& (webApplicationContext.getServletContext() == null || (MOCK_SERVLET_CONTEXT_AVAILABLE
+						&& webApplicationContext.getServletContext() instanceof MockServletContext));
 	}
 
 	private ClassPathScanningCandidateComponentProvider createComponentProvider() {

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/MockWebEnvironmentServletComponentScanIntegrationTests.java

@@ -0,0 +1,140 @@
+/*
+ * Copyright 2012-2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.web.servlet;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.Map;
+import java.util.Properties;
+
+import jakarta.servlet.MultipartConfigElement;
+import jakarta.servlet.annotation.WebFilter;
+import jakarta.servlet.annotation.WebListener;
+import jakarta.servlet.annotation.WebServlet;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.boot.testsupport.classpath.ForkedClassPath;
+import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebApplicationContext;
+import org.springframework.boot.web.servlet.testcomponents.filter.TestFilter;
+import org.springframework.boot.web.servlet.testcomponents.listener.TestListener;
+import org.springframework.boot.web.servlet.testcomponents.servlet.TestMultipartServlet;
+import org.springframework.boot.web.servlet.testcomponents.servlet.TestServlet;
+import org.springframework.mock.web.MockServletContext;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.BDDMockito.then;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Integration tests for {@link ServletComponentScan @ServletComponentScan} with a mock
+ * web environment.
+ *
+ * @author Andy Wilkinson
+ */
+class MockWebEnvironmentServletComponentScanIntegrationTests {
+
+	private AnnotationConfigServletWebApplicationContext context;
+
+	@TempDir
+	File temp;
+
+	@AfterEach
+	void cleanUp() {
+		if (this.context != null) {
+			this.context.close();
+		}
+	}
+
+	@Test
+	@ForkedClassPath
+	void componentsAreRegistered() {
+		prepareContext();
+		this.context.refresh();
+		Map<String, RegistrationBean> registrationBeans = this.context.getBeansOfType(RegistrationBean.class);
+		assertThat(registrationBeans).hasSize(3);
+		assertThat(registrationBeans.keySet()).containsExactlyInAnyOrder(TestServlet.class.getName(),
+				TestFilter.class.getName(), TestMultipartServlet.class.getName());
+		WebListenerRegistry registry = mock(WebListenerRegistry.class);
+		this.context.getBean(WebListenerRegistrar.class).register(registry);
+		then(registry).should().addWebListeners(TestListener.class.getName());
+	}
+
+	@Test
+	@ForkedClassPath
+	void indexedComponentsAreRegistered() throws IOException {
+		writeIndex(this.temp);
+		prepareContext();
+		try (URLClassLoader classLoader = new URLClassLoader(new URL[] { this.temp.toURI().toURL() },
+				getClass().getClassLoader())) {
+			this.context.setClassLoader(classLoader);
+			this.context.refresh();
+			Map<String, RegistrationBean> registrationBeans = this.context.getBeansOfType(RegistrationBean.class);
+			assertThat(registrationBeans).hasSize(2);
+			assertThat(registrationBeans.keySet()).containsExactlyInAnyOrder(TestServlet.class.getName(),
+					TestFilter.class.getName());
+			WebListenerRegistry registry = mock(WebListenerRegistry.class);
+			this.context.getBean(WebListenerRegistrar.class).register(registry);
+			then(registry).should().addWebListeners(TestListener.class.getName());
+		}
+	}
+
+	@Test
+	@ForkedClassPath
+	void multipartConfigIsHonoured() {
+		prepareContext();
+		this.context.refresh();
+		@SuppressWarnings("rawtypes")
+		Map<String, ServletRegistrationBean> beans = this.context.getBeansOfType(ServletRegistrationBean.class);
+		ServletRegistrationBean<?> servletRegistrationBean = beans.get(TestMultipartServlet.class.getName());
+		assertThat(servletRegistrationBean).isNotNull();
+		MultipartConfigElement multipartConfig = servletRegistrationBean.getMultipartConfig();
+		assertThat(multipartConfig).isNotNull();
+		assertThat(multipartConfig.getLocation()).isEqualTo("test");
+		assertThat(multipartConfig.getMaxRequestSize()).isEqualTo(2048);
+		assertThat(multipartConfig.getMaxFileSize()).isEqualTo(1024);
+		assertThat(multipartConfig.getFileSizeThreshold()).isEqualTo(512);
+	}
+
+	private void writeIndex(File temp) throws IOException {
+		File metaInf = new File(temp, "META-INF");
+		metaInf.mkdirs();
+		Properties index = new Properties();
+		index.setProperty(TestFilter.class.getName(), WebFilter.class.getName());
+		index.setProperty(TestListener.class.getName(), WebListener.class.getName());
+		index.setProperty(TestServlet.class.getName(), WebServlet.class.getName());
+		try (FileWriter writer = new FileWriter(new File(metaInf, "spring.components"))) {
+			index.store(writer, null);
+		}
+	}
+
+	private void prepareContext() {
+		this.context = new AnnotationConfigServletWebApplicationContext();
+		this.context.register(ScanningConfiguration.class);
+		this.context.setServletContext(new MockServletContext());
+	}
+
+	@ServletComponentScan(basePackages = "org.springframework.boot.web.servlet.testcomponents")
+	static class ScanningConfiguration {
+
+	}
+
+}