Merge branch '2.0.x'

spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/client/TraceWebClientBeanPostProcessor.java

@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.sleuth.instrument.web.client;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.function.Consumer;
 
@@ -27,6 +28,8 @@ import brave.propagation.Propagation;
 import brave.propagation.TraceContext;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import reactor.core.publisher.Mono;
+
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.config.BeanPostProcessor;
@@ -36,7 +39,6 @@ import org.springframework.web.reactive.function.client.ClientResponse;
 import org.springframework.web.reactive.function.client.ExchangeFilterFunction;
 import org.springframework.web.reactive.function.client.ExchangeFunction;
 import org.springframework.web.reactive.function.client.WebClient;
-import reactor.core.publisher.Mono;
 
 /**
  * {@link BeanPostProcessor} to wrap a {@link WebClient} instance into its trace
@@ -87,10 +89,20 @@ class TraceWebClientBeanPostProcessor implements BeanPostProcessor {
 
 class TraceExchangeFilterFunction implements ExchangeFilterFunction {
 
+	private static final Log log = LogFactory.getLog(TraceExchangeFilterFunction.class);
+
+	private static final String CLIENT_SPAN_KEY = "sleuth.webclient.clientSpan";
+
 	static final Propagation.Setter<ClientRequest.Builder, String> SETTER = new Propagation.Setter<ClientRequest.Builder, String>() {
 		@Override
 		public void put(ClientRequest.Builder carrier, String key, String value) {
-			carrier.header(key, value);
+			carrier.headers(httpHeaders -> {
+				if (log.isTraceEnabled()) {
+					log.trace("Replacing [" + key + "] with value [" + value + "]");
+				}
+				httpHeaders.merge(key, Collections.singletonList(value),
+						(oldValue, newValue) -> newValue);
+			});
 		}
 
 		@Override
@@ -98,21 +110,10 @@ class TraceExchangeFilterFunction implements ExchangeFilterFunction {
 			return "ClientRequest.Builder::header";
 		}
 	};
-	static final Propagation.Getter<ClientRequest, String> GETTER = new Propagation.Getter<ClientRequest, String>() {
-		@Override
-		public String get(ClientRequest carrier, String key) {
-			return carrier.headers().getFirst(key);
-		}
 
-		@Override
-		public String toString() {
-			return "HttpHeaders::getFirst";
-		}
-	};
-
-	private static final Log log = LogFactory.getLog(TraceExchangeFilterFunction.class);
-
-	private static final String CLIENT_SPAN_KEY = "sleuth.webclient.clientSpan";
+	public static ExchangeFilterFunction create(BeanFactory beanFactory) {
+		return new TraceExchangeFilterFunction(beanFactory);
+	}
 
 	final BeanFactory beanFactory;
 
@@ -128,16 +129,15 @@ class TraceExchangeFilterFunction implements ExchangeFilterFunction {
 		this.beanFactory = beanFactory;
 	}
 
-	public static ExchangeFilterFunction create(BeanFactory beanFactory) {
-		return new TraceExchangeFilterFunction(beanFactory);
-	}
-
 	@Override
 	public Mono<ClientResponse> filter(ClientRequest request, ExchangeFunction next) {
 		final ClientRequest.Builder builder = ClientRequest.from(request);
 		Mono<ClientResponse> exchange = Mono.defer(() -> next.exchange(builder.build()))
 				.cast(Object.class).onErrorResume(Mono::just)
 				.zipWith(Mono.subscriberContext()).flatMap(anyAndContext -> {
+					if (log.isDebugEnabled()) {
+						log.debug("Wrapping the context [" + anyAndContext + "]");
+					}
 					Object any = anyAndContext.getT1();
 					Span clientSpan = anyAndContext.getT2().get(CLIENT_SPAN_KEY);
 					Mono<ClientResponse> continuation;

spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/client/GH1102Tests.java

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2013-2018 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
+ *
+ *      http://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.cloud.sleuth.instrument.web.client;
+
+import brave.ScopedSpan;
+import brave.Tracer;
+import brave.sampler.Sampler;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.assertj.core.api.BDDAssertions;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import reactor.core.publisher.Mono;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.boot.web.server.LocalServerPort;
+import org.springframework.cloud.sleuth.util.ArrayListSpanReporter;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.reactive.function.client.WebClient;
+import org.springframework.web.reactive.function.client.WebClientResponseException;
+
+@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
+@RunWith(SpringRunner.class)
+public class GH1102Tests {
+
+	@Autowired
+	Tracer tracer;
+
+	@Autowired
+	WebClient webClient;
+
+	@Autowired
+	TestRetry testRetry;
+
+	@Autowired
+	ArrayListSpanReporter reporter;
+
+	@LocalServerPort
+	int port;
+
+	@Test
+	public void should_store_retries_as_separate_spans() throws Exception {
+		ScopedSpan foo = this.tracer.startScopedSpan("foo");
+		try {
+			this.webClient.get().uri("http://localhost:" + this.port + "/test").retrieve()
+					.bodyToMono(String.class).retry(1).block();
+			BDDAssertions.fail("should throw exception");
+		}
+		catch (WebClientResponseException ex) {
+
+		}
+		finally {
+			foo.finish();
+		}
+
+		BDDAssertions.then(this.testRetry.getHttpHeaders().get("x-b3-traceid"))
+				.hasSize(1);
+	}
+
+	@EnableAutoConfiguration
+	@Configuration
+	static class WebConfig {
+
+		@Bean
+		Sampler sampler() {
+			return Sampler.ALWAYS_SAMPLE;
+		}
+
+		@Bean
+		ArrayListSpanReporter reporter() {
+			return new ArrayListSpanReporter();
+		}
+
+		@Bean
+		WebClient webClient() {
+			return WebClient.builder().build();
+		}
+
+		@Bean
+		TestRetry testRetry() {
+			return new TestRetry();
+		}
+
+	}
+
+	@RestController
+	static class TestRetry {
+
+		private static final Log log = LogFactory.getLog(TestRetry.class);
+
+		private MultiValueMap<String, String> httpHeaders;
+
+		@GetMapping("test")
+		Mono<String> test(@RequestHeader MultiValueMap<String, String> map) {
+			this.httpHeaders = map;
+			log.info("Processing test. Headers [" + this.httpHeaders + "]");
+			return Mono.error(new RuntimeException("BOOM!"));
+		}
+
+		MultiValueMap<String, String> getHttpHeaders() {
+			return this.httpHeaders;
+		}
+
+	}
+
+}

spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/client/GH846Tests.java

@@ -31,9 +31,9 @@ import org.springframework.http.client.ClientHttpRequestInterceptor;
 import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.web.client.RestTemplate;
 
-@SpringBootTest(classes = GH846Test.App.class, webEnvironment = WebEnvironment.NONE)
+@SpringBootTest(classes = GH846Tests.App.class, webEnvironment = WebEnvironment.NONE)
 @RunWith(SpringRunner.class)
-public class GH846Test {
+public class GH846Tests {
 
 	@Autowired
 	private MyBean myBean;

spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/web/client/TraceWebClientBeanPostProcessorTest.java

@@ -16,12 +16,18 @@
 
 package org.springframework.cloud.sleuth.instrument.web.client;
 
+import java.net.URI;
+
+import brave.propagation.Propagation;
 import org.assertj.core.api.BDDAssertions;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.junit.MockitoJUnitRunner;
+
 import org.springframework.beans.factory.BeanFactory;
+import org.springframework.http.HttpMethod;
+import org.springframework.web.reactive.function.client.ClientRequest;
 import org.springframework.web.reactive.function.client.WebClient;
 
 /**