Introduce request attributes in RestClient

This commit introduces request attributes in the RestClient and
underlying infrastructure (i.e. HttpRequest).

Closes gh-32027

framework-docs/modules/ROOT/pages/integration/rest-clients.adoc

@@ -1007,7 +1007,8 @@ method parameters:
   is supported for non-String values.
 
 | `@RequestAttribute`
-| Provide an `Object` to add as a request attribute. Only supported by `WebClient`.
+| Provide an `Object` to add as a request attribute. Only supported by `RestClient`
+  and `WebClient`.
 
 | `@RequestBody`
 | Provide the body of the request either as an Object to be serialized, or a

spring-test/src/main/java/org/springframework/mock/http/client/MockClientHttpRequest.java

@@ -18,6 +18,8 @@ package org.springframework.mock.http.client;
 
 import java.io.IOException;
 import java.net.URI;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.http.HttpMethod;
 import org.springframework.http.client.ClientHttpRequest;
@@ -46,6 +48,9 @@ public class MockClientHttpRequest extends MockHttpOutputMessage implements Clie
 
 	private boolean executed = false;
 
+	@Nullable
+	Map<String, Object> attributes;
+
 
 	/**
 	 * Create a {@code MockClientHttpRequest} with {@link HttpMethod#GET GET} as
@@ -115,6 +120,16 @@ public class MockClientHttpRequest extends MockHttpOutputMessage implements Clie
 		return this.executed;
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		Map<String, Object> attributes = this.attributes;
+		if (attributes == null) {
+			attributes = new ConcurrentHashMap<>();
+			this.attributes = attributes;
+		}
+		return attributes;
+	}
+
 	/**
 	 * Set the {@link #isExecuted() executed} flag to {@code true} and return the
 	 * configured {@link #setResponse(ClientHttpResponse) response}.

spring-web/src/main/java/org/springframework/http/HttpRequest.java

@@ -17,6 +17,7 @@
 package org.springframework.http;
 
 import java.net.URI;
+import java.util.Map;
 
 /**
  * Represents an HTTP request message, consisting of a
@@ -41,4 +42,10 @@ public interface HttpRequest extends HttpMessage {
 	 */
 	URI getURI();
 
+	/**
+	 * Return a mutable map of request attributes for this request.
+	 * @since 6.2
+	 */
+	Map<String, Object> getAttributes();
+
 }

spring-web/src/main/java/org/springframework/http/client/AbstractClientHttpRequest.java

@@ -18,6 +18,8 @@ package org.springframework.http.client;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.LinkedHashMap;
+import java.util.Map;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.lang.Nullable;
@@ -39,6 +41,9 @@ public abstract class AbstractClientHttpRequest implements ClientHttpRequest {
 	@Nullable
 	private HttpHeaders readOnlyHeaders;
 
+	@Nullable
+	private Map<String, Object> attributes;
+
 
 	@Override
 	public final HttpHeaders getHeaders() {
@@ -60,6 +65,16 @@ public abstract class AbstractClientHttpRequest implements ClientHttpRequest {
 		return getBodyInternal(this.headers);
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		Map<String, Object> attributes = this.attributes;
+		if (attributes == null) {
+			attributes = new LinkedHashMap<>();
+			this.attributes = attributes;
+		}
+		return attributes;
+	}
+
 	@Override
 	public final ClientHttpResponse execute() throws IOException {
 		assertNotExecuted();

spring-web/src/main/java/org/springframework/http/client/InterceptingClientHttpRequest.java

@@ -91,6 +91,7 @@ class InterceptingClientHttpRequest extends AbstractBufferingClientHttpRequest {
 				HttpMethod method = request.getMethod();
 				ClientHttpRequest delegate = requestFactory.createRequest(request.getURI(), method);
 				request.getHeaders().forEach((key, value) -> delegate.getHeaders().addAll(key, value));
+				request.getAttributes().forEach((key, value) -> delegate.getAttributes().put(key, value));
 				if (body.length > 0) {
 					if (delegate instanceof StreamingHttpOutputMessage streamingOutputMessage) {
 						streamingOutputMessage.setBody(new StreamingHttpOutputMessage.Body() {

spring-web/src/main/java/org/springframework/http/client/support/HttpRequestWrapper.java

@@ -17,6 +17,7 @@
 package org.springframework.http.client.support;
 
 import java.net.URI;
+import java.util.Map;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
@@ -70,6 +71,14 @@ public class HttpRequestWrapper implements HttpRequest {
 		return this.request.getURI();
 	}
 
+	/**
+	 * Return the attributes of the wrapped request.
+	 */
+	@Override
+	public Map<String, Object> getAttributes() {
+		return this.request.getAttributes();
+	}
+
 	/**
 	 * Return the headers of the wrapped request.
 	 */

spring-web/src/main/java/org/springframework/http/server/ServletServerHttpRequest.java

@@ -29,11 +29,16 @@ import java.net.URLEncoder;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.security.Principal;
+import java.util.AbstractCollection;
+import java.util.AbstractMap;
+import java.util.AbstractSet;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import jakarta.servlet.http.HttpServletRequest;
 
@@ -67,6 +72,10 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 	@Nullable
 	private HttpHeaders headers;
 
+	@Nullable
+	private Map<String, Object> attributes;
+
+
 	@Nullable
 	private ServerHttpAsyncRequestControl asyncRequestControl;
 
@@ -207,6 +216,16 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 		return new InetSocketAddress(this.servletRequest.getRemoteHost(), this.servletRequest.getRemotePort());
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		Map<String, Object> attributes = this.attributes;
+		if (attributes == null) {
+			attributes = new AttributesMap();
+			this.attributes = attributes;
+		}
+		return attributes;
+	}
+
 	@Override
 	public InputStream getBody() throws IOException {
 		if (isFormPost(this.servletRequest) && this.servletRequest.getQueryString() == null) {
@@ -276,4 +295,151 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 		return new ByteArrayInputStream(bytes);
 	}
 
+
+	private final class AttributesMap extends AbstractMap<String, Object> {
+
+		@Nullable
+		private transient Set<String> keySet;
+
+		@Nullable
+		private transient Collection<Object> values;
+
+		@Nullable
+		private transient Set<Entry<String, Object>> entrySet;
+
+
+		@Override
+		public int size() {
+			int size = 0;
+			for (Enumeration<?> names = servletRequest.getAttributeNames(); names.hasMoreElements(); names.nextElement()) {
+				size++;
+			}
+			return size;
+		}
+
+		@Override
+		@Nullable
+		public Object get(Object key) {
+			if (key instanceof String name) {
+				return servletRequest.getAttribute(name);
+			}
+			else {
+				return null;
+			}
+		}
+
+		@Override
+		@Nullable
+		public Object put(String key, Object value) {
+			Object old = get(key);
+			servletRequest.setAttribute(key, value);
+			return old;
+		}
+
+		@Override
+		@Nullable
+		public Object remove(Object key) {
+			if (key instanceof String name) {
+				Object old = get(key);
+				servletRequest.removeAttribute(name);
+				return old;
+			}
+			else {
+				return null;
+			}
+		}
+
+		@Override
+		public void clear() {
+			for (Enumeration<String> names = servletRequest.getAttributeNames(); names.hasMoreElements(); ) {
+				String name = names.nextElement();
+				servletRequest.removeAttribute(name);
+			}
+		}
+
+		@Override
+		public Set<String> keySet() {
+			Set<String> keySet = this.keySet;
+			if (keySet == null) {
+				keySet = new AbstractSet<>() {
+					@Override
+					public Iterator<String> iterator() {
+						return servletRequest.getAttributeNames().asIterator();
+					}
+
+					@Override
+					public int size() {
+						return AttributesMap.this.size();
+					}
+				};
+				this.keySet = keySet;
+			}
+			return keySet;
+		}
+
+		@Override
+		public Collection<Object> values() {
+			Collection<Object> values = this.values;
+			if (values == null) {
+				values = new AbstractCollection<>() {
+					@Override
+					public Iterator<Object> iterator() {
+						Enumeration<String> e = servletRequest.getAttributeNames();
+						return new Iterator<>() {
+							@Override
+							public boolean hasNext() {
+								return e.hasMoreElements();
+							}
+
+							@Override
+							public Object next() {
+								String name = e.nextElement();
+								return servletRequest.getAttribute(name);
+							}
+						};
+					}
+
+					@Override
+					public int size() {
+						return AttributesMap.this.size();
+					}
+				};
+				this.values = values;
+			}
+			return values;
+		}
+
+		@Override
+		public Set<Entry<String, Object>> entrySet() {
+			Set<Entry<String, Object>> entrySet = this.entrySet;
+			if (entrySet == null) {
+				entrySet = new AbstractSet<>() {
+					@Override
+					public Iterator<Entry<String, Object>> iterator() {
+						Enumeration<String> e = servletRequest.getAttributeNames();
+						return new Iterator<>() {
+							@Override
+							public boolean hasNext() {
+								return e.hasMoreElements();
+							}
+
+							@Override
+							public Entry<String, Object> next() {
+								String name = e.nextElement();
+								Object value = servletRequest.getAttribute(name);
+								return new SimpleImmutableEntry<>(name, value);
+							}
+						};
+					}
+
+					@Override
+					public int size() {
+						return AttributesMap.this.size();
+					}
+				};
+				this.entrySet = entrySet;
+			}
+			return entrySet;
+		}
+	}
 }

spring-web/src/main/java/org/springframework/http/server/reactive/AbstractServerHttpRequest.java

@@ -19,6 +19,9 @@ package org.springframework.http.server.reactive;
 import java.net.URI;
 import java.net.URLDecoder;
 import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.Map;
+import java.util.function.Supplier;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -68,6 +71,9 @@ public abstract class AbstractServerHttpRequest implements ServerHttpRequest {
 	@Nullable
 	private String logPrefix;
 
+	@Nullable
+	private Supplier<Map<String, Object>> attributesSupplier;
+
 
 	/**
 	 * Constructor with the method, URI and headers for the request.
@@ -122,6 +128,16 @@ public abstract class AbstractServerHttpRequest implements ServerHttpRequest {
 		return this.uri;
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		if (this.attributesSupplier != null) {
+			return this.attributesSupplier.get();
+		}
+		else {
+			return Collections.emptyMap();
+		}
+	}
+
 	@Override
 	public RequestPath getPath() {
 		return this.path;
@@ -230,4 +246,12 @@ public abstract class AbstractServerHttpRequest implements ServerHttpRequest {
 		return getId();
 	}
 
+	/**
+	 * Set the attribute supplier.
+	 * <p><strong>Note:</strong> This is exposed mainly for internal framework
+	 * use.
+	 */
+	public void setAttributesSupplier(Supplier<Map<String, Object>> attributesSupplier) {
+		this.attributesSupplier = attributesSupplier;
+	}
 }

spring-web/src/main/java/org/springframework/http/server/reactive/ServerHttpRequestDecorator.java

@@ -18,6 +18,7 @@ package org.springframework.http.server.reactive;
 
 import java.net.InetSocketAddress;
 import java.net.URI;
+import java.util.Map;
 
 import reactor.core.publisher.Flux;
 
@@ -70,6 +71,11 @@ public class ServerHttpRequestDecorator implements ServerHttpRequest {
 		return getDelegate().getURI();
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		return getDelegate().getAttributes();
+	}
+
 	@Override
 	public RequestPath getPath() {
 		return getDelegate().getPath();

spring-web/src/main/java/org/springframework/web/client/DefaultRestClient.java

@@ -28,6 +28,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
@@ -82,6 +83,8 @@ final class DefaultRestClient implements RestClient {
 
 	private static final ClientRequestObservationConvention DEFAULT_OBSERVATION_CONVENTION = new DefaultClientRequestObservationConvention();
 
+	private static final String URI_TEMPLATE_ATTRIBUTE = RestClient.class.getName() + ".uriTemplate";
+
 
 	private final ClientHttpRequestFactory clientRequestFactory;
 
@@ -297,7 +300,7 @@ final class DefaultRestClient implements RestClient {
 		private InternalBody body;
 
 		@Nullable
-		private String uriTemplate;
+		private Map<String, Object> attributes;
 
 		@Nullable
 		private Consumer<ClientHttpRequest> httpRequestConsumer;
@@ -308,19 +311,19 @@ final class DefaultRestClient implements RestClient {
 
 		@Override
 		public RequestBodySpec uri(String uriTemplate, Object... uriVariables) {
-			this.uriTemplate = uriTemplate;
+			attribute(URI_TEMPLATE_ATTRIBUTE, uriTemplate);
 			return uri(DefaultRestClient.this.uriBuilderFactory.expand(uriTemplate, uriVariables));
 		}
 
 		@Override
 		public RequestBodySpec uri(String uriTemplate, Map<String, ?> uriVariables) {
-			this.uriTemplate = uriTemplate;
+			attribute(URI_TEMPLATE_ATTRIBUTE, uriTemplate);
 			return uri(DefaultRestClient.this.uriBuilderFactory.expand(uriTemplate, uriVariables));
 		}
 
 		@Override
 		public RequestBodySpec uri(String uriTemplate, Function<UriBuilder, URI> uriFunction) {
-			this.uriTemplate = uriTemplate;
+			attribute(URI_TEMPLATE_ATTRIBUTE, uriTemplate);
 			return uri(uriFunction.apply(DefaultRestClient.this.uriBuilderFactory.uriString(uriTemplate)));
 		}
 
@@ -392,6 +395,27 @@ final class DefaultRestClient implements RestClient {
 			return this;
 		}
 
+		@Override
+		public RequestBodySpec attribute(String name, Object value) {
+			getAttributes().put(name, value);
+			return this;
+		}
+
+		@Override
+		public RequestBodySpec attributes(Consumer<Map<String, Object>> attributesConsumer) {
+			attributesConsumer.accept(getAttributes());
+			return this;
+		}
+
+		private Map<String, Object> getAttributes() {
+			Map<String, Object> attributes = this.attributes;
+			if (attributes == null) {
+				attributes = new ConcurrentHashMap<>(4);
+				this.attributes = attributes;
+			}
+			return attributes;
+		}
+
 		@Override
 		public RequestBodySpec httpRequest(Consumer<ClientHttpRequest> requestConsumer) {
 			this.httpRequestConsumer = (this.httpRequestConsumer != null ?
@@ -483,8 +507,10 @@ final class DefaultRestClient implements RestClient {
 				HttpHeaders headers = initHeaders();
 				ClientHttpRequest clientRequest = createRequest(uri);
 				clientRequest.getHeaders().addAll(headers);
+				Map<String, Object> attributes = getAttributes();
+				clientRequest.getAttributes().putAll(attributes);
 				ClientRequestObservationContext observationContext = new ClientRequestObservationContext(clientRequest);
-				observationContext.setUriTemplate(this.uriTemplate);
+				observationContext.setUriTemplate((String) attributes.get(URI_TEMPLATE_ATTRIBUTE));
 				observation = ClientHttpObservationDocumentation.HTTP_CLIENT_EXCHANGES.observation(observationConvention,
 						DEFAULT_OBSERVATION_CONVENTION, () -> observationContext, observationRegistry).start();
 				if (this.body != null) {

spring-web/src/main/java/org/springframework/web/client/RestClient.java

@@ -498,6 +498,24 @@ public interface RestClient {
 		 */
 		S headers(Consumer<HttpHeaders> headersConsumer);
 
+		/**
+		 * Set the attribute with the given name to the given value.
+		 * @param name the name of the attribute to add
+		 * @param value the value of the attribute to add
+		 * @return this builder
+		 * @since 6.2
+		 */
+		S attribute(String name, Object value);
+
+		/**
+		 * Provides access to every attribute declared so far with the
+		 * possibility to add, replace, or remove values.
+		 * @param attributesConsumer the consumer to provide access to
+		 * @return this builder
+		 * @since 6.2
+		 */
+		S attributes(Consumer<Map<String, Object>> attributesConsumer);
+
 		/**
 		 * Callback for access to the {@link ClientHttpRequest} that in turn
 		 * provides access to the native request of the underlying HTTP library.

spring-web/src/main/java/org/springframework/web/client/support/RestClientAdapter.java

@@ -56,7 +56,7 @@ public final class RestClientAdapter implements HttpExchangeAdapter {
 
 	@Override
 	public boolean supportsRequestAttributes() {
-		return false;
+		return true;
 	}
 
 	@Override
@@ -121,6 +121,8 @@ public final class RestClientAdapter implements HttpExchangeAdapter {
 			bodySpec.header(HttpHeaders.COOKIE, String.join("; ", cookies));
 		}
 
+		bodySpec.attributes(attributes -> attributes.putAll(values.getAttributes()));
+
 		if (values.getBodyValue() != null) {
 			bodySpec.body(values.getBodyValue());
 		}

spring-web/src/main/java/org/springframework/web/server/adapter/DefaultServerWebExchange.java

@@ -42,6 +42,7 @@ import org.springframework.http.MediaType;
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.ServerCodecConfigurer;
 import org.springframework.http.codec.multipart.Part;
+import org.springframework.http.server.reactive.AbstractServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpResponse;
 import org.springframework.lang.Nullable;
@@ -137,6 +138,10 @@ public class DefaultServerWebExchange implements ServerWebExchange {
 		this.formDataMono = initFormData(request, codecConfigurer, getLogPrefix());
 		this.multipartDataMono = initMultipartData(codecConfigurer, getLogPrefix());
 		this.applicationContext = applicationContext;
+
+		if (request instanceof AbstractServerHttpRequest abstractServerHttpRequest) {
+			abstractServerHttpRequest.setAttributesSupplier(() -> this.attributes);
+		}
 	}
 
 	private static Mono<MultiValueMap<String, String>> initFormData(ServerHttpRequest request,

spring-web/src/test/java/org/springframework/http/client/InterceptingClientHttpRequestFactoryTests.java

@@ -115,6 +115,32 @@ class InterceptingClientHttpRequestFactoryTests {
 		request.execute();
 	}
 
+	@Test
+	void changeAttribute() throws Exception {
+		final String attrName = "Foo";
+		final String attrValue = "Bar";
+
+		ClientHttpRequestInterceptor interceptor = (request, body, execution) -> {
+			System.out.println("interceptor");
+			request.getAttributes().put(attrName, attrValue);
+			return execution.execute(request, body);
+		};
+
+		requestMock = new MockClientHttpRequest() {
+			@Override
+			protected ClientHttpResponse executeInternal() {
+				System.out.println("execute");
+				assertThat(getAttributes()).containsEntry(attrName, attrValue);
+				return responseMock;
+			}
+		};
+
+		requestFactory = new InterceptingClientHttpRequestFactory(requestFactoryMock, Collections.singletonList(interceptor));
+
+		ClientHttpRequest request = requestFactory.createRequest(URI.create("https://example.com"), HttpMethod.GET);
+		request.execute();
+	}
+
 	@Test
 	void changeURI() throws Exception {
 		final URI changedUri = URI.create("https://example.com/2");

spring-web/src/test/java/org/springframework/http/server/ServletServerHttpRequestTests.java

@@ -217,4 +217,10 @@ class ServletServerHttpRequestTests {
 		assertThat(request.getHeaders().getContentLength()).isEqualTo(result.length);
 	}
 
+	@Test
+	void attributes() {
+		request.getAttributes().put("foo", "bar");
+		assertThat(mockRequest.getAttribute("foo")).isEqualTo("bar");
+	}
+
 }

spring-web/src/test/java/org/springframework/web/util/ForwardedHeaderUtilsTests.java

@@ -17,6 +17,8 @@
 package org.springframework.web.util;
 
 import java.net.URI;
+import java.util.Collections;
+import java.util.Map;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -363,6 +365,11 @@ class ForwardedHeaderUtilsTests {
 				return UriComponentsBuilder.fromUriString("/").build().toUri();
 			}
 
+			@Override
+			public Map<String, Object> getAttributes() {
+				return Collections.emptyMap();
+			}
+
 			@Override
 			public HttpHeaders getHeaders() {
 				return new HttpHeaders();

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/client/MockClientHttpRequest.java

@@ -18,6 +18,8 @@ package org.springframework.web.testfixture.http.client;
 
 import java.io.IOException;
 import java.net.URI;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.http.HttpMethod;
 import org.springframework.http.client.ClientHttpRequest;
@@ -46,6 +48,9 @@ public class MockClientHttpRequest extends MockHttpOutputMessage implements Clie
 
 	private boolean executed = false;
 
+	@Nullable
+	Map<String, Object> attributes;
+
 
 	/**
 	 * Create a {@code MockClientHttpRequest} with {@link HttpMethod#GET GET} as
@@ -115,6 +120,16 @@ public class MockClientHttpRequest extends MockHttpOutputMessage implements Clie
 		return this.executed;
 	}
 
+	@Override
+	public Map<String, Object> getAttributes() {
+		Map<String, Object> attributes = this.attributes;
+		if (attributes == null) {
+			attributes = new ConcurrentHashMap<>();
+			this.attributes = attributes;
+		}
+		return attributes;
+	}
+
 	/**
 	 * Set the {@link #isExecuted() executed} flag to {@code true} and return the
 	 * configured {@link #setResponse(ClientHttpResponse) response}.

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/DefaultClientResponseBuilder.java

@@ -18,6 +18,8 @@ package org.springframework.web.reactive.function.client;
 
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.Map;
 import java.util.function.Consumer;
 import java.util.function.Function;
 
@@ -65,6 +67,11 @@ final class DefaultClientResponseBuilder implements ClientResponse.Builder {
 		public HttpHeaders getHeaders() {
 			return HttpHeaders.EMPTY;
 		}
+
+		@Override
+		public Map<String, Object> getAttributes() {
+			return Collections.emptyMap();
+		}
 	};
 
 

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/ExchangeFunctions.java

@@ -17,6 +17,7 @@
 package org.springframework.web.reactive.function.client;
 
 import java.net.URI;
+import java.util.Map;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -149,6 +150,11 @@ public abstract class ExchangeFunctions {
 					return request.url();
 				}
 
+				@Override
+				public Map<String, Object> getAttributes() {
+					return request.attributes();
+				}
+
 				@Override
 				public HttpHeaders getHeaders() {
 					return request.headers();

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultServerRequestBuilder.java

@@ -193,7 +193,7 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 	@Override
 	public ServerRequest build() {
 		ServerHttpRequest serverHttpRequest = new BuiltServerHttpRequest(this.exchange.getRequest().getId(),
-				this.method, this.uri, this.contextPath, this.headers, this.cookies, this.body);
+				this.method, this.uri, this.contextPath, this.headers, this.cookies, this.body, this.attributes);
 		ServerWebExchange exchange = new DelegatingServerWebExchange(
 				serverHttpRequest, this.attributes, this.exchange, this.messageReaders);
 		return new DefaultServerRequest(exchange, this.messageReaders);
@@ -220,8 +220,10 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
 		private final Flux<DataBuffer> body;
 
+		private final Map<String, Object> attributes;
+
 		public BuiltServerHttpRequest(String id, HttpMethod method, URI uri, @Nullable String contextPath,
-				HttpHeaders headers, MultiValueMap<String, HttpCookie> cookies, Flux<DataBuffer> body) {
+				HttpHeaders headers, MultiValueMap<String, HttpCookie> cookies, Flux<DataBuffer> body, Map<String, Object> attributes) {
 
 			this.id = id;
 			this.method = method;
@@ -231,6 +233,7 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 			this.cookies = unmodifiableCopy(cookies);
 			this.queryParams = parseQueryParams(uri);
 			this.body = body;
+			this.attributes = attributes;
 		}
 
 		private static <K, V> MultiValueMap<K, V> unmodifiableCopy(MultiValueMap<K, V> original) {
@@ -273,6 +276,11 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 			return this.uri;
 		}
 
+		@Override
+		public Map<String, Object> getAttributes() {
+			return this.attributes;
+		}
+
 		@Override
 		public RequestPath getPath() {
 			return this.path;

spring-webflux/src/test/java/org/springframework/web/reactive/function/client/DefaultClientResponseTests.java

@@ -19,6 +19,7 @@ package org.springframework.web.reactive.function.client;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.OptionalLong;
@@ -324,6 +325,11 @@ class DefaultClientResponseTests {
 			public HttpHeaders getHeaders() {
 				return HttpHeaders.EMPTY;
 			}
+
+			@Override
+			public Map<String, Object> getAttributes() {
+				return Collections.emptyMap();
+			}
 		};
 
 		given(mockExchangeStrategies.messageReaders()).willReturn(