Add possibility for custom MimeMappings

Add a new property called 'mime-mappings' under the 'server' property.
This is a key-value-map, which is added to the default MimeMappings.

See gh-38902

Author: BenchmarkingBuffalo

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

@@ -37,6 +37,7 @@
 import org.springframework.boot.web.server.Compression;
 import org.springframework.boot.web.server.Cookie;
 import org.springframework.boot.web.server.Http2;
+import org.springframework.boot.web.server.MimeMappings;
 import org.springframework.boot.web.server.Shutdown;
 import org.springframework.boot.web.server.Ssl;
 import org.springframework.boot.web.servlet.server.Encoding;
@@ -71,6 +72,7 @@
  * @author Parviz Rozikov
  * @author Florian Storz
  * @author Michael Weidmann
+ * @author Lasse Wulff
  * @since 1.0.0
  */
 @ConfigurationProperties(prefix = "server", ignoreUnknownFields = true)
@@ -115,6 +117,8 @@ public class ServerProperties {
 	@NestedConfigurationProperty
 	private final Compression compression = new Compression();
 
+	private final MimeMappings mimeMappings = MimeMappings.lazyCopy(MimeMappings.DEFAULT);
+
 	@NestedConfigurationProperty
 	private final Http2 http2 = new Http2();
 
@@ -197,6 +201,14 @@ public Compression getCompression() {
 		return this.compression;
 	}
 
+	public MimeMappings getMimeMappings() {
+		return this.mimeMappings;
+	}
+
+	public void setMimeMappings(Map<String, String> customMappings) {
+		customMappings.forEach(this.mimeMappings::add);
+	}
+
 	public Http2 getHttp2() {
 		return this.http2;
 	}

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

@@ -38,6 +38,7 @@
  * @author Olivier Lamy
  * @author Yunkun Huang
  * @author Scott Frederick
+ * @author Lasse Wulff
  * @since 2.0.0
  */
 public class ServletWebServerFactoryCustomizer
@@ -94,6 +95,7 @@ public void customize(ConfigurableServletWebServerFactory factory) {
 		map.from(() -> this.cookieSameSiteSuppliers)
 			.whenNot(CollectionUtils::isEmpty)
 			.to(factory::setCookieSameSiteSuppliers);
+		map.from(this.serverProperties::getMimeMappings).to(factory::setMimeMappings);
 		this.webListenerRegistrars.forEach((registrar) -> registrar.register(factory));
 	}
 

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

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.autoconfigure.web;
 
-import java.io.IOException;
 import java.net.InetAddress;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
@@ -27,7 +26,6 @@
 import java.util.concurrent.atomic.AtomicReference;
 
 import io.undertow.UndertowOptions;
-import jakarta.servlet.ServletException;
 import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
@@ -42,6 +40,7 @@
 import org.eclipse.jetty.server.Request;
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.util.thread.QueuedThreadPool;
+import org.jetbrains.annotations.NotNull;
 import org.junit.jupiter.api.Test;
 import reactor.netty.http.HttpDecoderSpec;
 
@@ -55,7 +54,8 @@
 import org.springframework.boot.web.embedded.jetty.JettyServletWebServerFactory;
 import org.springframework.boot.web.embedded.jetty.JettyWebServer;
 import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
-import org.springframework.boot.web.servlet.ServletContextInitializer;
+import org.springframework.boot.web.server.MimeMappings;
+import org.springframework.boot.web.server.MimeMappings.Mapping;
 import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
@@ -84,6 +84,7 @@
  * @author Rafiullah Hamedy
  * @author Chris Bono
  * @author Parviz Rozikov
+ * @author Lasse Wulff
  */
 @DirtiesUrlFactories
 class ServerPropertiesTests {
@@ -199,6 +200,21 @@ void testContextPathWithLeadingAndTrailingWhitespaceAndContextWithSpace() {
 		assertThat(this.properties.getServlet().getContextPath()).isEqualTo("/assets /copy");
 	}
 
+	@Test
+	void testDefaultMimeMapping() {
+		assertThat(this.properties.getMimeMappings()).containsExactly(
+				MimeMappings.DEFAULT.getAll().toArray(new Mapping[0]));
+	}
+
+	@Test
+	void testCustomizedMimeMapping() {
+		MimeMappings expectedMappings = MimeMappings.lazyCopy(MimeMappings.DEFAULT);
+		expectedMappings.add("mjs", "text/javascript");
+		bind("server.mime-mappings.mjs", "text/javascript");
+		assertThat(this.properties.getMimeMappings()).containsExactly(
+				expectedMappings.getAll().toArray(new Mapping[0]));
+	}
+
 	@Test
 	void testCustomizeUriEncoding() {
 		bind("server.tomcat.uri-encoding", "US-ASCII");
@@ -479,12 +495,11 @@ void jettyThreadPoolPropertyDefaultsShouldMatchServerDefault() {
 	void jettyMaxHttpFormPostSizeMatchesDefault() {
 		JettyServletWebServerFactory jettyFactory = new JettyServletWebServerFactory(0);
 		JettyWebServer jetty = (JettyWebServer) jettyFactory
-			.getWebServer((ServletContextInitializer) (servletContext) -> servletContext
+			.getWebServer((servletContext) -> servletContext
 				.addServlet("formPost", new HttpServlet() {
 
 					@Override
-					protected void doPost(HttpServletRequest req, HttpServletResponse resp)
-							throws ServletException, IOException {
+					protected void doPost(HttpServletRequest req, HttpServletResponse resp) {
 						req.getParameterMap();
 					}
 
@@ -506,12 +521,12 @@ public void onDispatchFailure(Request request, Throwable ex) {
 			template.setErrorHandler(new ResponseErrorHandler() {
 
 				@Override
-				public boolean hasError(ClientHttpResponse response) throws IOException {
+				public boolean hasError(@NotNull ClientHttpResponse response) {
 					return false;
 				}
 
 				@Override
-				public void handleError(ClientHttpResponse response) throws IOException {
+				public void handleError(@NotNull ClientHttpResponse response) {
 
 				}
 

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

@@ -45,6 +45,7 @@
  *
  * @author Brian Clozel
  * @author Yunkun Huang
+ * @author Lasse Wulff
  */
 class ServletWebServerFactoryCustomizerTests {
 
@@ -72,6 +73,13 @@ void testCustomizeDisplayName() {
 		then(factory).should().setDisplayName("TestName");
 	}
 
+	@Test
+	void testCustomMimeMappings() {
+		ConfigurableServletWebServerFactory factory = mock(ConfigurableServletWebServerFactory.class);
+		this.customizer.customize(factory);
+		then(factory).should().setMimeMappings(this.properties.getMimeMappings());
+	}
+
 	@Test
 	void testCustomizeDefaultServlet() {
 		ConfigurableServletWebServerFactory factory = mock(ConfigurableServletWebServerFactory.class);