From 4a47c1eff85f8919be01f22d9cec8a309527b851 Mon Sep 17 00:00:00 2001
From: Brian Clozel <bclozel@pivotal.io>
Date: Fri, 12 May 2017 14:43:05 +0200
Subject: [PATCH] Keep default Thymeleaf media types in reactive support

This commit removes the default configuration value previously set
for `spring.thymeleaf.reactive.media-types` since this value overrides
the defaults provided by Thymeleaf.

This value does not drive the default media type used by views, but
rather all media types that the templating engine should support.

Fixes gh-9134
---
 .../thymeleaf/ThymeleafAutoConfiguration.java             | 8 ++++++--
 .../boot/autoconfigure/thymeleaf/ThymeleafProperties.java | 5 +----
 .../main/asciidoc/appendix-application-properties.adoc    | 2 +-
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
index 22ebd40f93..f4398accce 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java
@@ -19,6 +19,7 @@ package org.springframework.boot.autoconfigure.thymeleaf;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashMap;
+import java.util.List;
 
 import javax.annotation.PostConstruct;
 
@@ -55,6 +56,7 @@ import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.Ordered;
+import org.springframework.http.MediaType;
 import org.springframework.util.MimeType;
 import org.springframework.web.servlet.resource.ResourceUrlEncodingFilter;
 
@@ -252,8 +254,10 @@ public class ThymeleafAutoConfiguration {
 			ThymeleafReactiveViewResolver resolver = new ThymeleafReactiveViewResolver();
 			resolver.setTemplateEngine(templateEngine);
 			resolver.setDefaultCharset(this.properties.getEncoding());
-			resolver.setSupportedMediaTypes(
-					this.properties.getReactive().getMediaTypes());
+			final List<MediaType> mediaTypes = this.properties.getReactive().getMediaTypes();
+			if (mediaTypes != null) {
+				resolver.setSupportedMediaTypes(mediaTypes);
+			}
 			resolver.setExcludedViewNames(this.properties.getExcludedViewNames());
 			resolver.setViewNames(this.properties.getViewNames());
 			if (this.properties.getReactive().getMaxChunkSize() > 0) {
diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafProperties.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafProperties.java
index daa5386a72..e403f505b6 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafProperties.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafProperties.java
@@ -17,8 +17,6 @@
 package org.springframework.boot.autoconfigure.thymeleaf;
 
 import java.nio.charset.Charset;
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -227,8 +225,7 @@ public class ThymeleafProperties {
 		/**
 		 * Media types supported by the view technology.
 		 */
-		private List<MediaType> mediaTypes = new ArrayList<>(
-				Collections.singletonList(MediaType.TEXT_HTML));
+		private List<MediaType> mediaTypes;
 
 		public List<MediaType> getMediaTypes() {
 			return this.mediaTypes;
diff --git a/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc b/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc
index 5a62db5471..f5c55b3910 100644
--- a/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc
+++ b/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc
@@ -441,7 +441,7 @@ content into your application; rather pick only the properties that you need.
 	spring.thymeleaf.mode=HTML5 # Template mode to be applied to templates. See also StandardTemplateModeHandlers.
 	spring.thymeleaf.prefix=classpath:/templates/ # Prefix that gets prepended to view names when building a URL.
 	spring.thymeleaf.reactive.max-chunk-size= # Maximum size of data buffers used for writing to the response, in bytes.
-	spring.thymeleaf.reactive.media-types=text/html # Media types supported by the view technology.
+	spring.thymeleaf.reactive.media-types= # Media types supported by the view technology.
 	spring.thymeleaf.servlet.content-type=text/html # Content-Type value written to HTTP responses.
 	spring.thymeleaf.suffix=.html # Suffix that gets appended to view names when building a URL.
 	spring.thymeleaf.template-resolver-order= # Order of the template resolver in the chain.