Rework welcome page so that it only handles reqs that accept text/html

Closes gh-6668

Author: wilkinsona

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration.java

@@ -24,6 +24,7 @@
 import java.util.Map.Entry;
 
 import javax.servlet.Servlet;
+import javax.servlet.http.HttpServletRequest;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -57,6 +58,7 @@
 import org.springframework.format.Formatter;
 import org.springframework.format.FormatterRegistry;
 import org.springframework.format.datetime.DateFormatter;
+import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 import org.springframework.http.converter.HttpMessageConverter;
 import org.springframework.validation.DefaultMessageCodesResolver;
@@ -79,13 +81,14 @@
 import org.springframework.web.servlet.config.annotation.ResourceChainRegistration;
 import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistration;
 import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
-import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 import org.springframework.web.servlet.handler.AbstractHandlerExceptionResolver;
+import org.springframework.web.servlet.handler.AbstractUrlHandlerMapping;
 import org.springframework.web.servlet.handler.SimpleUrlHandlerMapping;
 import org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver;
 import org.springframework.web.servlet.i18n.FixedLocaleResolver;
+import org.springframework.web.servlet.mvc.ParameterizableViewController;
 import org.springframework.web.servlet.mvc.method.annotation.ExceptionHandlerExceptionResolver;
 import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;
 import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
@@ -288,6 +291,12 @@ public void addResourceHandlers(ResourceHandlerRegistry registry) {
 			}
 		}
 
+		@Bean
+		public WelcomePageHandlerMapping welcomePageHandlerMapping(
+				ResourceProperties resourceProperties) {
+			return new WelcomePageHandlerMapping(resourceProperties.getWelcomePage());
+		}
+
 		private void customizeResourceHandlerRegistration(
 				ResourceHandlerRegistration registration) {
 			if (this.resourceHandlerRegistrationCustomizer != null) {
@@ -296,15 +305,6 @@ private void customizeResourceHandlerRegistration(
 
 		}
 
-		@Override
-		public void addViewControllers(ViewControllerRegistry registry) {
-			Resource page = this.resourceProperties.getWelcomePage();
-			if (page != null) {
-				logger.info("Adding welcome page: " + page);
-				registry.addViewController("/").setViewName("forward:index.html");
-			}
-		}
-
 		@Bean
 		@ConditionalOnMissingBean({ RequestContextListener.class,
 				RequestContextFilter.class })
@@ -498,4 +498,32 @@ private ResourceResolver getVersionResourceResolver(
 
 	}
 
+	static final class WelcomePageHandlerMapping extends AbstractUrlHandlerMapping {
+
+		private static final Log logger = LogFactory
+				.getLog(WelcomePageHandlerMapping.class);
+
+		private WelcomePageHandlerMapping(Resource welcomePage) {
+			if (welcomePage != null) {
+				logger.info("Adding welcome page: " + welcomePage);
+				ParameterizableViewController controller = new ParameterizableViewController();
+				controller.setViewName("forward:index.html");
+				setRootHandler(controller);
+				setOrder(0);
+			}
+		}
+
+		@Override
+		public Object getHandlerInternal(HttpServletRequest request) throws Exception {
+			for (MediaType mediaType : MediaType
+					.parseMediaTypes(request.getHeader(HttpHeaders.ACCEPT))) {
+				if (mediaType.includes(MediaType.TEXT_HTML)) {
+					return super.getHandlerInternal(request);
+				}
+			}
+			return null;
+		}
+
+	}
+
 }

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/WebMvcAutoConfigurationTests.java

@@ -39,6 +39,7 @@
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration;
 import org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration.WebMvcAutoConfigurationAdapter;
+import org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration.WelcomePageHandlerMapping;
 import org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext;
 import org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizerBeanPostProcessor;
 import org.springframework.boot.context.embedded.EmbeddedServletContainerFactory;
@@ -52,8 +53,11 @@
 import org.springframework.core.io.Resource;
 import org.springframework.format.support.FormattingConversionService;
 import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
 import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.test.util.ReflectionTestUtils;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.web.accept.ContentNegotiationManager;
@@ -90,6 +94,9 @@
 import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.forwardedUrl;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
 /**
  * Tests for {@link WebMvcAutoConfiguration}.
@@ -132,7 +139,7 @@ public void handlerAdaptersCreated() throws Exception {
 	public void handlerMappingsCreated() throws Exception {
 		load();
 		assertThat(this.context.getBeanNamesForType(HandlerMapping.class).length)
-				.isEqualTo(6);
+				.isEqualTo(7);
 	}
 
 	@Test
@@ -540,6 +547,51 @@ public void customLogResolvedException() {
 		testLogResolvedExceptionCustomization(true);
 	}
 
+	@Test
+	public void welcomePageMappingProducesNotFoundResponseWhenThereIsNoWelcomePage()
+			throws Exception {
+		load("spring.resources.static-locations:classpath:/no-welcome-page/");
+		assertThat(this.context.getBeansOfType(WelcomePageHandlerMapping.class))
+				.hasSize(1);
+		MockMvcBuilders.webAppContextSetup(this.context).build()
+				.perform(get("/").accept(MediaType.TEXT_HTML))
+				.andExpect(status().isNotFound());
+	}
+
+	@Test
+	public void welcomePageMappingHandlesRequestsThatAcceptTextHtml() throws Exception {
+		load("spring.resources.static-locations:classpath:/welcome-page/");
+		assertThat(this.context.getBeansOfType(WelcomePageHandlerMapping.class))
+				.hasSize(1);
+		MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.context).build();
+		mockMvc.perform(get("/").accept(MediaType.TEXT_HTML)).andExpect(status().isOk())
+				.andExpect(forwardedUrl("index.html"));
+		mockMvc.perform(get("/").accept("*/*")).andExpect(status().isOk())
+				.andExpect(forwardedUrl("index.html"));
+	}
+
+	@Test
+	public void welcomePageMappingOnlyHandlesRequestsThatAcceptTextHtml()
+			throws Exception {
+		load("spring.resources.static-locations:classpath:/welcome-page/");
+		assertThat(this.context.getBeansOfType(WelcomePageHandlerMapping.class))
+				.hasSize(1);
+		MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.context).build();
+		mockMvc.perform(get("/").accept(MediaType.APPLICATION_JSON))
+				.andExpect(status().isNotFound());
+	}
+
+	@Test
+	public void welcomePageMappingWorksWithNoTrailingSlashOnResourceLocation()
+			throws Exception {
+		load("spring.resources.static-locations:classpath:/welcome-page");
+		assertThat(this.context.getBeansOfType(WelcomePageHandlerMapping.class))
+				.hasSize(1);
+		MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.context).build();
+		mockMvc.perform(get("/").accept(MediaType.TEXT_HTML)).andExpect(status().isOk())
+				.andExpect(forwardedUrl("index.html"));
+	}
+
 	private void testLogResolvedExceptionCustomization(final boolean expected) {
 		HandlerExceptionResolver exceptionResolver = this.context
 				.getBean(HandlerExceptionResolver.class);