Polish

Polish resource handling chain support. Make sure that the chain is
enabled automatically if at least one strategy is enabled.

See gh-1604

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/thymeleaf/ThymeleafAutoConfiguration.java

@@ -57,6 +57,7 @@ import com.github.mxab.thymeleaf.extras.dataattribute.dialect.DataAttributeDiale
  * @author Dave Syer
  * @author Andy Wilkinson
  * @author Stephane Nicoll
+ * @author Brian Clozel
  */
 @Configuration
 @EnableConfigurationProperties(ThymeleafProperties.class)

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/velocity/VelocityAutoConfiguration.java

@@ -51,6 +51,7 @@ import org.springframework.web.servlet.view.velocity.VelocityViewResolver;
  * {@link EnableAutoConfiguration Auto-configuration} for Velocity.
  *
  * @author Andy Wilkinson
+ * @author Brian Clozel
  * @since 1.1.0
  */
 @Configuration

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

@@ -16,6 +16,8 @@
 
 package org.springframework.boot.autoconfigure.web;
 
+import javax.annotation.PostConstruct;
+
 import org.springframework.boot.context.properties.ConfigurationProperties;
 
 /**
@@ -40,6 +42,15 @@ public class ResourceProperties {
 
 	private final Chain chain = new Chain();
 
+
+	@PostConstruct
+	public void setUpDefaults() {
+		if (this.chain.enabled == null && (this.chain.strategy.content.enabled
+				|| this.chain.strategy.fixed.enabled)) {
+			this.chain.enabled = true;
+		}
+	}
+
 	public Integer getCachePeriod() {
 		return this.cachePeriod;
 	}
@@ -66,9 +77,10 @@ public class ResourceProperties {
 	public static class Chain {
 
 		/**
-		 * Enable the Spring Resource Handling chain.
+		 * Enable the Spring Resource Handling chain. Disabled by default unless
+		 * at least one strategy has been enabled.
 		 */
-		private boolean enabled = false;
+		private Boolean enabled;
 
 		/**
 		 * Enable caching in the Resource chain.
@@ -80,9 +92,9 @@ public class ResourceProperties {
 		 */
 		private boolean html5AppCache = false;
 
-		private Strategy strategy = new Strategy();
+		private final Strategy strategy = new Strategy();
 
-		public boolean isEnabled() {
+		public Boolean getEnabled() {
 			return enabled;
 		}
 
@@ -116,9 +128,9 @@ public class ResourceProperties {
 	 */
 	public static class Strategy {
 
-		private Fixed fixed = new Fixed();
+		private final Fixed fixed = new Fixed();
 
-		private Content content = new Content();
+		private final Content content = new Content();
 
 		public Fixed getFixed() {
 			return fixed;
@@ -137,7 +149,7 @@ public class ResourceProperties {
 		/**
 		 * Enable the content Version Strategy.
 		 */
-		private boolean enabled = false;
+		private boolean enabled;
 
 		/**
 		 * Comma-separated list of patterns to apply to the Version Strategy.
@@ -169,7 +181,7 @@ public class ResourceProperties {
 		/**
 		 * Enable the fixed Version Strategy.
 		 */
-		private boolean enabled = false;
+		private boolean enabled;
 
 		/**
 		 * Comma-separated list of patterns to apply to the Version Strategy.

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

@@ -55,6 +55,7 @@ import org.springframework.format.Formatter;
 import org.springframework.format.FormatterRegistry;
 import org.springframework.format.datetime.DateFormatter;
 import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.validation.DefaultMessageCodesResolver;
 import org.springframework.validation.MessageCodesResolver;
@@ -274,7 +275,7 @@ public class WebMvcAutoConfiguration {
 
 		private void registerResourceChain(ResourceHandlerRegistration registration) {
 			ResourceProperties.Chain chainProperties = this.resourceProperties.getChain();
-			if (chainProperties.isEnabled()) {
+			if (ObjectUtils.nullSafeEquals(chainProperties.getEnabled(), Boolean.TRUE)) {
 				ResourceChainRegistration chain = registration.resourceChain(chainProperties.isCache());
 				boolean hasFixedVersionConfigured = chainProperties.getStrategy().getFixed().isEnabled();
 				boolean hasContentVersionConfigured = chainProperties.getStrategy().getContent().isEnabled();

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

@@ -169,12 +169,8 @@ public class WebMvcAutoConfigurationTests {
 
 	@Test
 	public void resourceHandlerChainEnabled() throws Exception {
-		this.context = new AnnotationConfigEmbeddedWebApplicationContext();
-		EnvironmentTestUtils.addEnvironment(this.context, "spring.resources.chain.enabled:true");
-		this.context.register(Config.class, WebMvcAutoConfiguration.class,
-				HttpMessageConvertersAutoConfiguration.class,
-				PropertyPlaceholderAutoConfiguration.class);
-		this.context.refresh();
+		load("spring.resources.chain.enabled:true");
+
 		assertThat(getResourceResolvers("/webjars/**").size(), equalTo(2));
 		assertThat(getResourceTransformers("/webjars/**").size(), equalTo(1));
 		assertThat(getResourceResolvers("/**").size(), equalTo(2));
@@ -185,21 +181,55 @@ public class WebMvcAutoConfigurationTests {
 		assertThat(getResourceTransformers("/**"), contains(instanceOf(CachingResourceTransformer.class)));
 	}
 
+	@Test
+	public void resourceHandlerFixedStrategyEnabled() throws Exception {
+		load("spring.resources.chain.strategy.fixed.enabled:true",
+				"spring.resources.chain.strategy.fixed.version:test",
+				"spring.resources.chain.strategy.fixed.paths:/**/*.js");
+
+		assertThat(getResourceResolvers("/webjars/**").size(), equalTo(3));
+		assertThat(getResourceTransformers("/webjars/**").size(), equalTo(2));
+		assertThat(getResourceResolvers("/**").size(), equalTo(3));
+		assertThat(getResourceTransformers("/**").size(), equalTo(2));
+
+		assertThat(getResourceResolvers("/**"), contains(instanceOf(CachingResourceResolver.class),
+				instanceOf(VersionResourceResolver.class),
+				instanceOf(PathResourceResolver.class)));
+		assertThat(getResourceTransformers("/**"), contains(instanceOf(CachingResourceTransformer.class),
+				instanceOf(CssLinkResourceTransformer.class)));
+		VersionResourceResolver resolver = (VersionResourceResolver) getResourceResolvers("/**").get(1);
+		assertThat(resolver.getStrategyMap().get("/**/*.js"), instanceOf(FixedVersionStrategy.class));
+	}
+
+	@Test
+	public void resourceHandlerContentStrategyEnabled() throws Exception {
+		load("spring.resources.chain.strategy.content.enabled:true",
+				"spring.resources.chain.strategy.content.paths:/**,/*.png");
+
+		assertThat(getResourceResolvers("/webjars/**").size(), equalTo(3));
+		assertThat(getResourceTransformers("/webjars/**").size(), equalTo(2));
+		assertThat(getResourceResolvers("/**").size(), equalTo(3));
+		assertThat(getResourceTransformers("/**").size(), equalTo(2));
+
+		assertThat(getResourceResolvers("/**"), contains(instanceOf(CachingResourceResolver.class),
+				instanceOf(VersionResourceResolver.class),
+				instanceOf(PathResourceResolver.class)));
+		assertThat(getResourceTransformers("/**"), contains(instanceOf(CachingResourceTransformer.class),
+				instanceOf(CssLinkResourceTransformer.class)));
+		VersionResourceResolver resolver = (VersionResourceResolver) getResourceResolvers("/**").get(1);
+		assertThat(resolver.getStrategyMap().get("/*.png"), instanceOf(ContentVersionStrategy.class));
+	}
+
 	@Test
 	public void resourceHandlerChainCustomized() throws Exception {
-		this.context = new AnnotationConfigEmbeddedWebApplicationContext();
-		EnvironmentTestUtils.addEnvironment(this.context,
-				"spring.resources.chain.enabled:true", "spring.resources.chain.cache:false",
+		load("spring.resources.chain.enabled:true", "spring.resources.chain.cache:false",
 				"spring.resources.chain.strategy.content.enabled:true",
 				"spring.resources.chain.strategy.content.paths:/**,/*.png",
 				"spring.resources.chain.strategy.fixed.enabled:true",
 				"spring.resources.chain.strategy.fixed.version:test",
 				"spring.resources.chain.strategy.fixed.paths:/**/*.js",
 				"spring.resources.chain.html5AppCache:true");
-		this.context.register(Config.class, WebMvcAutoConfiguration.class,
-				HttpMessageConvertersAutoConfiguration.class,
-				PropertyPlaceholderAutoConfiguration.class);
-		this.context.refresh();
+
 		assertThat(getResourceResolvers("/webjars/**").size(), equalTo(2));
 		assertThat(getResourceTransformers("/webjars/**").size(), equalTo(2));
 		assertThat(getResourceResolvers("/**").size(), equalTo(2));

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -129,7 +129,7 @@ content into your application; rather pick only the properties that you need.
 	# SPRING RESOURCES HANDLING ({sc-spring-boot-autoconfigure}/web/ResourceProperties.{sc-ext}[ResourceProperties])
 	spring.resources.cache-period= # cache timeouts in headers sent to browser
 	spring.resources.add-mappings=true # if default mappings should be added
-	spring.resources.chain.enabled=false # enable the Spring Resource Handling chain
+	spring.resources.chain.enabled=false # enable the Spring Resource Handling chain (enabled automatically if at least a strategy is enabled)
 	spring.resources.chain.cache=false # enable in-memory caching of resource resolution
 	spring.resources.chain.html5AppCache=false # enable HTML5 appcache manifest rewriting
 	spring.resources.chain.strategy.content.enabled=false # enable a content version strategy

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -1193,7 +1193,6 @@ for all static resources, effectively adding a content hash in URLs, such as
 
 [source,properties,indent=0,subs="verbatim,quotes,attributes"]
 ----
-	spring.resources.chain.enabled=true
 	spring.resources.chain.strategy.content.enabled=true
 	spring.resources.chain.strategy.content.paths=/**
 ----
@@ -1210,7 +1209,6 @@ A "fixed" strategy will add a static version string in the URL, without changing
 
 [source,properties,indent=0,subs="verbatim,quotes,attributes"]
 ----
-	spring.resources.chain.enabled=true
 	spring.resources.chain.strategy.content.enabled=true
 	spring.resources.chain.strategy.content.paths=/**
 	spring.resources.chain.strategy.fixed.enabled=true
@@ -1225,9 +1223,12 @@ the content one `<link href="/css/spring-2a2d595e6ed9a0b24f027f2b63b134d6.css"/>
 See {sc-spring-boot-autoconfigure}/web/ResourceProperties.{sc-ext}[`ResourceProperties`]
 for more of the supported options.
 
+[TIP]
+====
 This feature has been thoroughly described in a dedicated
 https://spring.io/blog/2014/07/24/spring-framework-4-1-handling-static-web-resources[blog post]
 and in Spring Framework's {spring-reference}/#mvc-config-static-resources[reference documentation].
+====
 
 
 [[boot-features-spring-mvc-template-engines]]