Provide explicit force request/response properties

Update HttpEncodingProperties to offer explicit `force-request` and
`force-reponse` properties in additional to the existing `force`
property.

Closes gh-5459

Author: philwebb

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

@@ -20,6 +20,7 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.autoconfigure.web.HttpEncodingProperties.Type;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.boot.web.filter.OrderedCharacterEncodingFilter;
 import org.springframework.context.annotation.Bean;
@@ -39,18 +40,19 @@
 @ConditionalOnProperty(prefix = "spring.http.encoding", value = "enabled", matchIfMissing = true)
 public class HttpEncodingAutoConfiguration {
 
-	private final HttpEncodingProperties httpEncodingProperties;
+	private final HttpEncodingProperties properties;
 
-	public HttpEncodingAutoConfiguration(HttpEncodingProperties httpEncodingProperties) {
-		this.httpEncodingProperties = httpEncodingProperties;
+	public HttpEncodingAutoConfiguration(HttpEncodingProperties properties) {
+		this.properties = properties;
 	}
 
 	@Bean
 	@ConditionalOnMissingBean(CharacterEncodingFilter.class)
 	public CharacterEncodingFilter characterEncodingFilter() {
 		CharacterEncodingFilter filter = new OrderedCharacterEncodingFilter();
-		filter.setEncoding(this.httpEncodingProperties.getCharset().name());
-		filter.setForceRequestEncoding(this.httpEncodingProperties.isForce());
+		filter.setEncoding(this.properties.getCharset().name());
+		filter.setForceRequestEncoding(this.properties.shouldForce(Type.REQUEST));
+		filter.setForceResponseEncoding(this.properties.shouldForce(Type.RESPONSE));
 		return filter;
 	}
 

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

@@ -40,7 +40,17 @@ public class HttpEncodingProperties {
 	/**
 	 * Force the encoding to the configured charset on HTTP requests and responses.
 	 */
-	private boolean force = true;
+	private Boolean force;
+
+	/**
+	 * Force the encoding to the configured charset on HTTP requests.
+	 */
+	private Boolean forceRequest;
+
+	/**
+	 * Force the encoding to the configured charset on HTTP responses.
+	 */
+	private Boolean forceResponse;
 
 	public Charset getCharset() {
 		return this.charset;
@@ -51,11 +61,42 @@ public void setCharset(Charset charset) {
 	}
 
 	public boolean isForce() {
-		return this.force;
+		return Boolean.TRUE.equals(this.force);
 	}
 
 	public void setForce(boolean force) {
 		this.force = force;
 	}
 
+	public boolean isForceRequest() {
+		return Boolean.TRUE.equals(this.forceRequest);
+	}
+
+	public void setForceRequest(boolean forceRequest) {
+		this.forceRequest = forceRequest;
+	}
+
+	public boolean isForceResponse() {
+		return Boolean.TRUE.equals(this.forceResponse);
+	}
+
+	public void setForceResponse(boolean forceResponse) {
+		this.forceResponse = forceResponse;
+	}
+
+	boolean shouldForce(Type type) {
+		Boolean force = (type == Type.REQUEST ? this.forceRequest : this.forceResponse);
+		if (force == null) {
+			force = this.force;
+		}
+		if (force == null) {
+			force = (type == Type.REQUEST ? true : false);
+		}
+		return force;
+	}
+
+	enum Type {
+		REQUEST, RESPONSE
+	}
+
 }

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

@@ -63,7 +63,7 @@ public void defaultConfiguration() {
 		load(EmptyConfiguration.class);
 		CharacterEncodingFilter filter = this.context
 				.getBean(CharacterEncodingFilter.class);
-		assertCharacterEncodingFilter(filter, "UTF-8", true);
+		assertCharacterEncodingFilter(filter, "UTF-8", true, false);
 	}
 
 	@Test
@@ -79,7 +79,7 @@ public void customConfiguration() {
 				"spring.http.encoding.force:false");
 		CharacterEncodingFilter filter = this.context
 				.getBean(CharacterEncodingFilter.class);
-		assertCharacterEncodingFilter(filter, "ISO-8859-15", false);
+		assertCharacterEncodingFilter(filter, "ISO-8859-15", false, false);
 	}
 
 	@Test
@@ -88,7 +88,41 @@ public void customFilterConfiguration() {
 				"spring.http.encoding.force:false");
 		CharacterEncodingFilter filter = this.context
 				.getBean(CharacterEncodingFilter.class);
-		assertCharacterEncodingFilter(filter, "US-ASCII", false);
+		assertCharacterEncodingFilter(filter, "US-ASCII", false, false);
+	}
+
+	@Test
+	public void forceRequest() throws Exception {
+		load(EmptyConfiguration.class, "spring.http.encoding.force-request:false");
+		CharacterEncodingFilter filter = this.context
+				.getBean(CharacterEncodingFilter.class);
+		assertCharacterEncodingFilter(filter, "UTF-8", false, false);
+	}
+
+	@Test
+	public void forceResponse() throws Exception {
+		load(EmptyConfiguration.class, "spring.http.encoding.force-response:true");
+		CharacterEncodingFilter filter = this.context
+				.getBean(CharacterEncodingFilter.class);
+		assertCharacterEncodingFilter(filter, "UTF-8", true, true);
+	}
+
+	@Test
+	public void forceRequestOverridesForce() throws Exception {
+		load(EmptyConfiguration.class, "spring.http.encoding.force:true",
+				"spring.http.encoding.force-request:false");
+		CharacterEncodingFilter filter = this.context
+				.getBean(CharacterEncodingFilter.class);
+		assertCharacterEncodingFilter(filter, "UTF-8", false, true);
+	}
+
+	@Test
+	public void forceResponseOverridesForce() throws Exception {
+		load(EmptyConfiguration.class, "spring.http.encoding.force:true",
+				"spring.http.encoding.force-response:false");
+		CharacterEncodingFilter filter = this.context
+				.getBean(CharacterEncodingFilter.class);
+		assertCharacterEncodingFilter(filter, "UTF-8", true, false);
 	}
 
 	@Test
@@ -102,10 +136,11 @@ public void filterIsOrderedHighest() throws Exception {
 	}
 
 	private void assertCharacterEncodingFilter(CharacterEncodingFilter actual,
-			String encoding, boolean forceRequestEncoding) {
+			String encoding, boolean forceRequestEncoding,
+			boolean forceResponseEncoding) {
 		assertThat(actual.getEncoding()).isEqualTo(encoding);
 		assertThat(actual.isForceRequestEncoding()).isEqualTo(forceRequestEncoding);
-		assertThat(actual.isForceResponseEncoding()).isFalse();
+		assertThat(actual.isForceResponseEncoding()).isEqualTo(forceResponseEncoding);
 	}
 
 	private void load(Class<?> config, String... environment) {

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

@@ -268,7 +268,9 @@ content into your application; rather pick only the properties that you need.
 	# HTTP encoding ({sc-spring-boot-autoconfigure}/web/HttpEncodingProperties.{sc-ext}[HttpEncodingProperties])
 	spring.http.encoding.charset=UTF-8 # Charset of HTTP requests and responses. Added to the "Content-Type" header if not set explicitly.
 	spring.http.encoding.enabled=true # Enable http encoding support.
-	spring.http.encoding.force=true # Force the encoding to the configured charset on HTTP requests and responses.
+	spring.http.encoding.force= # Force the encoding to the configured charset on HTTP requests and responses.
+	spring.http.encoding.force-request= # Force the encoding to the configured charset on HTTP requests (defaults to true when ".force" has not been specified).
+	spring.http.encoding.force-response= # Force the encoding to the configured charset on HTTP responses.
 
 	# MULTIPART ({sc-spring-boot-autoconfigure}/web/MultipartProperties.{sc-ext}[MultipartProperties])
 	spring.http.multipart.enabled=true # Enable support of multi-part uploads.