Add config property for webflux codec maxInMemorySize

This commit creates a new configuration property
`spring.codec.max-in-memory-size` which configures the maximum
amount of data to be buffered in memory by codecs (both client and
server).

This property has no default value - it will let Spring Framework handle
the default behavior, currently enforcing a 256KB for provided codecs.

Fixes gh-18828

Author: bclozel

Diff for: spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/codec/CodecProperties.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.codec;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.util.unit.DataSize;
+
+/**
+ * {@link ConfigurationProperties properties} for reactive codecs.
+ *
+ * @author Brian Clozel
+ * @since 2.2.1
+ */
+@ConfigurationProperties(prefix = "spring.codec")
+public class CodecProperties {
+
+	/**
+	 * Limit on the number of bytes that can be buffered whenever the input stream needs
+	 * to be aggregated. By default this is not set, in which case individual codec
+	 * defaults apply. Most codecs are limited to 256K by default.
+	 */
+	private DataSize maxInMemorySize;
+
+	public DataSize getMaxInMemorySize() {
+		return this.maxInMemorySize;
+	}
+
+	public void setMaxInMemorySize(DataSize maxInMemorySize) {
+		this.maxInMemorySize = maxInMemorySize;
+	}
+
+}

Diff for: spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/codec/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Auto-configuration for reactive codecs.
+ */
+package org.springframework.boot.autoconfigure.codec;

Diff for: spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/http/codec/CodecsAutoConfiguration.java

@@ -20,11 +20,13 @@
 
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.codec.CodecProperties;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.http.HttpProperties;
 import org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.web.codec.CodecCustomizer;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -33,6 +35,7 @@
 import org.springframework.http.codec.json.Jackson2JsonDecoder;
 import org.springframework.http.codec.json.Jackson2JsonEncoder;
 import org.springframework.util.MimeType;
+import org.springframework.util.unit.DataSize;
 import org.springframework.web.reactive.function.client.WebClient;
 
 /**
@@ -46,6 +49,7 @@
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnClass({ CodecConfigurer.class, WebClient.class })
 @AutoConfigureAfter(JacksonAutoConfiguration.class)
+@EnableConfigurationProperties({ HttpProperties.class, CodecProperties.class })
 public class CodecsAutoConfiguration {
 
 	private static final MimeType[] EMPTY_MIME_TYPES = {};
@@ -68,14 +72,18 @@ CodecCustomizer jacksonCodecCustomizer(ObjectMapper objectMapper) {
 	}
 
 	@Configuration(proxyBeanMethods = false)
-	@EnableConfigurationProperties(HttpProperties.class)
-	static class LoggingCodecConfiguration {
+	static class DefaultCodecsConfiguration {
 
 		@Bean
 		@Order(0)
-		CodecCustomizer loggingCodecCustomizer(HttpProperties properties) {
-			return (configurer) -> configurer.defaultCodecs()
-					.enableLoggingRequestDetails(properties.isLogRequestDetails());
+		CodecCustomizer defaultCodecCustomizer(HttpProperties httpProperties, CodecProperties codecProperties) {
+			return (configurer) -> {
+				PropertyMapper map = PropertyMapper.get();
+				CodecConfigurer.DefaultCodecs defaultCodecs = configurer.defaultCodecs();
+				defaultCodecs.enableLoggingRequestDetails(httpProperties.isLogRequestDetails());
+				map.from(codecProperties.getMaxInMemorySize()).whenNonNull().asInt(DataSize::toBytes)
+						.to(defaultCodecs::maxInMemorySize);
+			};
 		}
 
 	}

Diff for: spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/http/codec/CodecsAutoConfigurationTests.java

@@ -22,6 +22,7 @@
 import org.junit.jupiter.api.Test;
 
 import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.codec.CodecProperties;
 import org.springframework.boot.autoconfigure.http.HttpProperties;
 import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
 import org.springframework.boot.web.codec.CodecCustomizer;
@@ -67,11 +68,11 @@ void loggingRequestDetailsCustomizerShouldUseHttpProperties() {
 	}
 
 	@Test
-	void loggingRequestDetailsBeanShouldHaveOrderZero() {
+	void defaultCodecCustomizerBeanShouldHaveOrderZero() {
 		this.contextRunner.run((context) -> {
 			Method customizerMethod = ReflectionUtils.findMethod(
-					CodecsAutoConfiguration.LoggingCodecConfiguration.class, "loggingCodecCustomizer",
-					HttpProperties.class);
+					CodecsAutoConfiguration.DefaultCodecsConfiguration.class, "defaultCodecCustomizer",
+					HttpProperties.class, CodecProperties.class);
 			Integer order = new TestAnnotationAwareOrderComparator().findOrder(customizerMethod);
 			assertThat(order).isEqualTo(0);
 		});
@@ -98,6 +99,16 @@ void userProvidedCustomizerCanOverrideJacksonCodecCustomizer() {
 				});
 	}
 
+	@Test
+	void maxInMemorySizeEnforcedInDefaultCodecs() {
+		this.contextRunner.withPropertyValues("spring.codec.max-in-memory-size=1MB").run((context) -> {
+			CodecCustomizer customizer = context.getBean(CodecCustomizer.class);
+			CodecConfigurer configurer = new DefaultClientCodecConfigurer();
+			customizer.customize(configurer);
+			assertThat(configurer.defaultCodecs()).hasFieldOrPropertyWithValue("maxInMemorySize", 1048576);
+		});
+	}
+
 	static class TestAnnotationAwareOrderComparator extends AnnotationAwareOrderComparator {
 
 		@Override

Diff for: spring-boot-project/spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -2538,8 +2538,9 @@ If you want to take complete control of Spring WebFlux, you can add your own `@C
 Spring WebFlux uses the `HttpMessageReader` and `HttpMessageWriter` interfaces to convert HTTP requests and responses.
 They are configured with `CodecConfigurer` to have sensible defaults by looking at the libraries available in your classpath.
 
-Spring Boot applies further customization by using `CodecCustomizer` instances.
-For example, `spring.jackson.*` configuration keys are applied to the Jackson codec.
+Spring Boot provides dedicated configuration properties for codecs, `+spring.codec.*+`.
+It also applies further customization by using `CodecCustomizer` instances.
+For example, `+spring.jackson.*+` configuration keys are applied to the Jackson codec.
 
 If you need to add or customize codecs, you can create a custom `CodecCustomizer` component, as shown in the following example:
 
@@ -2554,7 +2555,7 @@ If you need to add or customize codecs, you can create a custom `CodecCustomizer
 		public CodecCustomizer myCodecCustomizer() {
 			return codecConfigurer -> {
 				// ...
-			}
+			};
 		}
 
 	}

Diff for: spring-boot-project/spring-boot-docs/src/main/groovy/generateConfigurationPropertyTables.groovy

@@ -24,7 +24,7 @@ def generateConfigMetadataDocumentation() {
 		builder
 				.addSection("core")
 					.withKeyPrefixes("debug", "trace", "logging", "spring.aop", "spring.application",
-						"spring.autoconfigure", "spring.banner", "spring.beaninfo", "spring.config",
+						"spring.autoconfigure", "spring.banner", "spring.beaninfo", "spring.codec", "spring.config",
 						"spring.info", "spring.jmx", "spring.main", "spring.messages", "spring.pid",
 						"spring.profiles", "spring.quartz", "spring.reactor", "spring.task",
 						"spring.mandatory-file-encoding", "info", "spring.output.ansi.enabled")