add TraceWebAspect to wrap Callable's returned in Controllers.

spring-cloud-sleuth-sample/src/main/java/org/springframework/cloud/sleuth/sample/SampleApplication.java

@@ -1,90 +1,38 @@
 package org.springframework.cloud.sleuth.sample;
 
-import java.util.Random;
-
-import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
-import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
 import org.springframework.cloud.sleuth.Sampler;
-import org.springframework.cloud.sleuth.Trace;
-import org.springframework.cloud.sleuth.TraceScope;
 import org.springframework.cloud.sleuth.sampler.AlwaysSampler;
-import org.springframework.context.ApplicationListener;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.EnableAspectJAutoProxy;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RestController;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.scheduling.annotation.EnableAsync;
 
 /**
  * @author Spencer Gibb
  */
 @Configuration
 @EnableAutoConfiguration
-@EnableAspectJAutoProxy
+@EnableAspectJAutoProxy(proxyTargetClass = true)
+@EnableAsync
 @Slf4j
 public class SampleApplication {
 
 	public static final String CLIENT_NAME = "testApp";
 
-	@RestController
-	protected static class SampleController implements
-			ApplicationListener<EmbeddedServletContainerInitializedEvent> {
-		@Autowired
-		private RestTemplate restTemplate;
-		@Autowired
-		private Trace trace;
-		private int port;
-
-		@SneakyThrows
-		@RequestMapping("/")
-		public String hi() {
-			final Random random = new Random();
-			Thread.sleep(random.nextInt(1000));
-
-			String s = restTemplate.getForObject("http://localhost:" + port + "/hi2",
-					String.class);
-			return "hi/" + s;
-		}
-
-		@SneakyThrows
-		@RequestMapping("/hi2")
-		public String hi2() {
-			final Random random = new Random();
-			Thread.sleep(random.nextInt(1000));
-			return "hi2";
-		}
-
-		@SneakyThrows
-		@RequestMapping("/traced")
-		public String traced() {
-			TraceScope scope = trace.startSpan("customTraceEndpoint", new AlwaysSampler());
-			final Random random = new Random();
-			int millis = random.nextInt(1000);
-			log.info("Sleeping for {} millis", millis);
-			Thread.sleep(millis);
-
-			String s = restTemplate.getForObject("http://localhost:" + port + "/hi2", String.class);
-			scope.close();
-			return "hi/" + s;
-		}
-
-		@Override
-		public void onApplicationEvent(EmbeddedServletContainerInitializedEvent event) {
-			port = event.getEmbeddedServletContainer().getPort();
-		}
-	}
-
 	@Bean
 	public Sampler defaultSampler() {
 		return new AlwaysSampler();
 	}
 
+	@Bean
+	public SampleController sampleController() {
+		return new SampleController();
+	}
+
 	public static void main(String[] args) {
 		SpringApplication.run(SampleApplication.class, args);
 	}

spring-cloud-sleuth-sample/src/main/java/org/springframework/cloud/sleuth/sample/SampleController.java

@@ -0,0 +1,82 @@
+package org.springframework.cloud.sleuth.sample;
+
+import lombok.SneakyThrows;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
+import org.springframework.cloud.sleuth.Span;
+import org.springframework.cloud.sleuth.Trace;
+import org.springframework.cloud.sleuth.TraceContextHolder;
+import org.springframework.cloud.sleuth.TraceScope;
+import org.springframework.cloud.sleuth.sampler.AlwaysSampler;
+import org.springframework.context.ApplicationListener;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.client.RestTemplate;
+
+import java.util.Random;
+import java.util.concurrent.Callable;
+
+/**
+ * @author Spencer Gibb
+ */
+@Slf4j
+@RestController
+class SampleController implements
+		ApplicationListener<EmbeddedServletContainerInitializedEvent> {
+	@Autowired
+	private RestTemplate restTemplate;
+	@Autowired
+	private Trace trace;
+	private int port;
+
+	@SneakyThrows
+	@RequestMapping("/")
+	public String hi() {
+		final Random random = new Random();
+		Thread.sleep(random.nextInt(1000));
+
+		String s = restTemplate.getForObject("http://localhost:" + port + "/hi2",
+				String.class);
+		return "hi/" + s;
+	}
+
+	@RequestMapping("/call")
+	public Callable<String> call() {
+		return new Callable<String>() {
+			@Override
+			public String call() throws Exception {
+				Span currentSpan = TraceContextHolder.getCurrentSpan();
+				return "async hi: "+currentSpan;
+			}
+		};
+	}
+
+
+	@SneakyThrows
+	@RequestMapping("/hi2")
+	public String hi2() {
+		final Random random = new Random();
+		Thread.sleep(random.nextInt(1000));
+		return "hi2";
+	}
+
+	@SneakyThrows
+	@RequestMapping("/traced")
+	public String traced() {
+		TraceScope scope = trace.startSpan("customTraceEndpoint", new AlwaysSampler());
+		final Random random = new Random();
+		int millis = random.nextInt(1000);
+		log.info("Sleeping for {} millis", millis);
+		Thread.sleep(millis);
+
+		String s = restTemplate.getForObject("http://localhost:" + port + "/hi2", String.class);
+		scope.close();
+		return "hi/" + s;
+	}
+
+	@Override
+	public void onApplicationEvent(EmbeddedServletContainerInitializedEvent event) {
+		port = event.getEmbeddedServletContainer().getPort();
+	}
+}