Merge branch 'master' into 2.0.x

README.adoc

@@ -322,6 +322,7 @@ Example of setting baggage on a span:
 ----
 Span initialSpan = this.tracer.createSpan("span");
 initialSpan.setBaggageItem("foo", "bar");
+initialSpan.setBaggageItem("UPPER_CASE", "someValue");
 ----
 
 ===== Baggage vs. Span Tags

docs/src/main/asciidoc/spring-cloud-sleuth.adoc

@@ -484,6 +484,26 @@ Stream based span reporting).
 spring.zipkin.locator.discovery.enabled: true
 ----
 
+== Sending spans to Zipkin
+
+By default if you add `spring-cloud-starter-zipkin` as a dependency to your project,
+when the span is closed, it will be sent to Zipkin over HTTP. The communication
+is asynchronous. You can configure the URL by setting the `spring.zipkin.baseUrl`
+property as follows:
+
+[source,yaml]
+----
+spring.zipkin.baseUrl: http://192.168.99.100:9411/
+----
+
+If you want to find Zipkin via service discovery it's enough to pass the
+Zipkin's service id inside the URL (example for `zipkinserver` service id)
+
+[source,yaml]
+----
+spring.zipkin.baseUrl: http://zipkinserver/
+----
+
 == Span Data as Messages
 
 You can accumulate and send span data over

pom.xml

@@ -226,12 +226,6 @@
 				<version>3.0.0</version>
 				<scope>test</scope>
 			</dependency>
-			<dependency>
-				<groupId>com.github.tomakehurst</groupId>
-				<artifactId>wiremock</artifactId>
-				<version>2.6.0</version>
-				<scope>test</scope>
-			</dependency>
 			<dependency>
 				<groupId>pl.pragmatists</groupId>
 				<artifactId>JUnitParams</artifactId>

spring-cloud-sleuth-zipkin/pom.xml

@@ -88,6 +88,11 @@
 			<artifactId>zipkin-junit</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.awaitility</groupId>
+			<artifactId>awaitility</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<!-- otherwise spring boot's version of okhttp kicks zipkin-junit's deps out of alignment -->
 		<dependency>
 			<groupId>com.squareup.okhttp3</groupId>

spring-cloud-sleuth-zipkin/src/main/java/org/springframework/cloud/sleuth/zipkin/ZipkinAutoConfiguration.java

@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.sleuth.zipkin;
 
+import java.net.URI;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -24,9 +25,11 @@ import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.web.ServerProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.cloud.client.ServiceInstance;
 import org.springframework.cloud.client.discovery.DiscoveryClient;
 import org.springframework.cloud.commons.util.InetUtils;
 import org.springframework.cloud.sleuth.Sampler;
@@ -64,6 +67,7 @@ import org.springframework.web.client.RestTemplate;
 public class ZipkinAutoConfiguration {
 
 	@Autowired(required = false) List<SpanAdjuster> spanAdjusters = new ArrayList<>();
+	@Autowired ZipkinUrlExtractor extractor;
 
 	@Bean
 	@ConditionalOnMissingBean
@@ -71,10 +75,51 @@ public class ZipkinAutoConfiguration {
 			ZipkinRestTemplateCustomizer zipkinRestTemplateCustomizer) {
 		RestTemplate restTemplate = new RestTemplate();
 		zipkinRestTemplateCustomizer.customize(restTemplate);
-		return new HttpZipkinSpanReporter(restTemplate, zipkin.getBaseUrl(), zipkin.getFlushInterval(),
+		String zipkinUrl = this.extractor.zipkinUrl(zipkin);
+		return new HttpZipkinSpanReporter(restTemplate, zipkinUrl, zipkin.getFlushInterval(),
 				spanMetricReporter);
 	}
 
+	@Configuration
+	@ConditionalOnClass(DiscoveryClient.class)
+	static class DiscoveryClientZipkinUrlExtractorConfiguration {
+
+		@Autowired(required = false) DiscoveryClient discoveryClient;
+
+		@Bean
+		ZipkinUrlExtractor zipkinUrlExtractor() {
+			final DiscoveryClient discoveryClient = this.discoveryClient;
+			return new ZipkinUrlExtractor() {
+				@Override
+				public String zipkinUrl(ZipkinProperties zipkinProperties) {
+					if (discoveryClient != null) {
+						URI uri = URI.create(zipkinProperties.getBaseUrl());
+						String host = uri.getHost();
+						List<ServiceInstance> instances = discoveryClient.getInstances(host);
+						if (!instances.isEmpty()) {
+							return instances.get(0).getUri().toString();
+						}
+					}
+					return zipkinProperties.getBaseUrl();
+				}
+			};
+		}
+	}
+
+	@Configuration
+	@ConditionalOnMissingClass("org.springframework.cloud.client.discovery.DiscoveryClient")
+	static class DefaultZipkinUrlExtractorConfiguration {
+		@Bean
+		ZipkinUrlExtractor zipkinUrlExtractor() {
+			return new ZipkinUrlExtractor() {
+				@Override
+				public String zipkinUrl(ZipkinProperties zipkinProperties) {
+					return zipkinProperties.getBaseUrl();
+				}
+			};
+		}
+	}
+
 	@Bean
 	@ConditionalOnMissingBean
 	public ZipkinRestTemplateCustomizer zipkinRestTemplateCustomizer(ZipkinProperties zipkinProperties) {
@@ -156,3 +201,7 @@ public class ZipkinAutoConfiguration {
 	}
 
 }
+
+interface ZipkinUrlExtractor {
+	String zipkinUrl(ZipkinProperties zipkinProperties);
+}

spring-cloud-sleuth-zipkin/src/main/java/org/springframework/cloud/sleuth/zipkin/ZipkinProperties.java

@@ -26,7 +26,10 @@ import org.springframework.boot.context.properties.ConfigurationProperties;
  */
 @ConfigurationProperties("spring.zipkin")
 public class ZipkinProperties {
-	/** URL of the zipkin query server instance. */
+	/** URL of the zipkin query server instance. You can also provide
+	 *  the service id of the Zipkin server if Zipkin's registered in
+	 *  service discovery (e.g. http://zipkinserver/)
+	 */
 	private String baseUrl = "http://localhost:9411/";
 	private boolean enabled = true;
 	private int flushInterval = 1;

spring-cloud-sleuth-zipkin/src/test/java/org/springframework/cloud/sleuth/zipkin/ZipkinDiscoveryClientTests.java

@@ -0,0 +1,118 @@
+package org.springframework.cloud.sleuth.zipkin;
+
+import static org.assertj.core.api.BDDAssertions.then;
+import static org.springframework.cloud.sleuth.zipkin.ZipkinDiscoveryClientTests.ZIPKIN_RULE;
+
+import java.io.IOException;
+import java.net.URI;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+
+import org.assertj.core.api.BDDAssertions;
+import org.awaitility.Awaitility;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.cloud.client.ServiceInstance;
+import org.springframework.cloud.client.discovery.DiscoveryClient;
+import org.springframework.cloud.sleuth.Span;
+import org.springframework.cloud.sleuth.SpanReporter;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.util.SocketUtils;
+
+import zipkin.junit.ZipkinRule;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = ZipkinDiscoveryClientTests.Config.class,
+		properties = "spring.zipkin.baseUrl=http://zipkin/")
+public class ZipkinDiscoveryClientTests {
+
+	@ClassRule public static ZipkinRule ZIPKIN_RULE = new ZipkinRule();
+
+	@Autowired SpanReporter spanReporter;
+
+	@Test
+	public void shouldUseDiscoveryClientToFindZipkinUrlIfPresent() throws Exception {
+		Span span = Span.builder().traceIdHigh(1L).traceId(2L).spanId(3L).name("foo")
+				.build();
+
+		this.spanReporter.report(span);
+
+		Awaitility.await().untilAsserted(() -> then(ZIPKIN_RULE.httpRequestCount()).isGreaterThan(0));
+	}
+
+	@Configuration
+	@EnableAutoConfiguration
+	static class Config {
+		@Bean
+		DiscoveryClient client() {
+			return new ZipkinDiscoveryClient();
+		}
+	}
+}
+
+
+class ZipkinDiscoveryClient implements DiscoveryClient {
+
+	@Override
+	public String description() {
+		return "";
+	}
+
+	@Override
+	public ServiceInstance getLocalServiceInstance() {
+		return null;
+	}
+
+	@Override
+	public List<ServiceInstance> getInstances(String s) {
+		if ("zipkin".equals(s)) {
+			return Collections.singletonList(new ServiceInstance() {
+				@Override
+				public String getServiceId() {
+					return "zipkin";
+				}
+
+				@Override
+				public String getHost() {
+					return "localhost";
+				}
+
+				@Override
+				public int getPort() {
+					return URI.create(ZIPKIN_RULE.httpUrl()).getPort();
+				}
+
+				@Override
+				public boolean isSecure() {
+					return false;
+				}
+
+				@Override
+				public URI getUri() {
+					return URI.create(ZIPKIN_RULE.httpUrl());
+				}
+
+				@Override
+				public Map<String, String> getMetadata() {
+					return null;
+				}
+			});
+		}
+		return Collections.emptyList();
+	}
+
+	@Override
+	public List<String> getServices() {
+		return Collections.singletonList("zipkin");
+	}
+
+}

spring-cloud-sleuth-zipkin/src/test/java/org/springframework/cloud/sleuth/zipkin/ZipkinSpanListenerTests.java

@@ -17,11 +17,16 @@
 package org.springframework.cloud.sleuth.zipkin;
 
 import org.assertj.core.api.Condition;
+import org.junit.Ignore;
+import org.springframework.cloud.client.ServiceInstance;
+import org.springframework.cloud.client.discovery.DiscoveryClient;
 import zipkin.Constants;
 
+import java.net.URI;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import javax.annotation.PostConstruct;
 
 import org.junit.Test;
@@ -56,7 +61,6 @@ import static org.junit.Assert.assertEquals;
 public class ZipkinSpanListenerTests {
 
 	@Autowired Tracer tracer;
-	@Autowired ApplicationContext application;
 	@Autowired TestConfiguration test;
 	@Autowired ZipkinSpanListener spanListener;
 	@Autowired ZipkinSpanReporter spanReporter;
@@ -337,4 +341,4 @@ public class ZipkinSpanListenerTests {
 
 	}
 
-}
+}