Updates to latest zipkin and brave, removing Scribe dependency

Recent versions of zipkin and brave operate with http instead of scribe.
This changes the implementation accordingly, as well adds a sampler to
the POST endpoint.

A notable impact is that we no longer require a collector process, as
the zipkin server's POST endpoint is a collector.

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/main/java/sample/SampleZipkinApplication.java

@@ -47,7 +47,7 @@ public class SampleZipkinApplication {
 		SpringApplication.run(SampleZipkinApplication.class, args);
 	}
 
-	// Use this for debugging (or if there is no Zipkin collector running on port 9410)
+	// Use this for debugging (or if there is no Zipkin server running on port 9411)
 	@Bean
 	@ConditionalOnProperty(value="sample.zipkin.enabled", havingValue="false")
 	public SpanCollector spanCollector() {

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/test/java/integration/ZipkinDockerTests.java

@@ -55,16 +55,12 @@ public class ZipkinDockerTests extends AbstractIntegrationTest {
 	public static DockerComposeContainer environment =
 			new DockerComposeContainer(new File("src/test/resources/docker-compose.yml"))
 					.withExposedService("rabbitmq_1", 5672)
-					.withExposedService("collector_1", 9410)
-					.withExposedService("collector_1", 9900)
 					.withExposedService("mysql_1", 3306)
-					.withExposedService("query_1", 9411)
-					.withExposedService("query_1", 9901);
+					.withExposedService("query_1", 9411);
 
 	@Before
 	public void setup() {
 		await().until(zipkinQueryServerIsUp());
-		await().until(zipkinCollectorServerIsUp());
 	}
 
 	@Test
@@ -96,7 +92,6 @@ public class ZipkinDockerTests extends AbstractIntegrationTest {
 
 	private List<String> serviceNamesNotFoundInZipkin(List<io.zipkin.Span> spans) {
 		List<String> serviceNamesFoundInAnnotations = spans.stream()
-				.filter(span -> span.annotations != null)
 				.map(span -> span.annotations)
 				.flatMap(Collection::stream)
 				.filter(span -> span.endpoint != null)
@@ -105,7 +100,6 @@ public class ZipkinDockerTests extends AbstractIntegrationTest {
 				.distinct()
 				.collect(Collectors.toList());
 		List<String> serviceNamesFoundInBinaryAnnotations = spans.stream()
-				.filter(span -> span.binaryAnnotations != null)
 				.map(span -> span.binaryAnnotations)
 				.flatMap(Collection::stream)
 				.filter(span -> span.endpoint != null)
@@ -122,7 +116,6 @@ public class ZipkinDockerTests extends AbstractIntegrationTest {
 	private List<String> annotationsNotFoundInZipkin(List<io.zipkin.Span> spans) {
 		String binaryAnnotationName = "random-sleep-millis";
 		Optional<String> names = spans.stream()
-				.filter(span -> span.binaryAnnotations != null)
 				.map(span -> span.binaryAnnotations)
 				.flatMap(Collection::stream)
 				.filter(span -> span.endpoint != null)

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/test/resources/docker-compose.yml

@@ -1,16 +1,5 @@
-collector:
-  image: openzipkin/zipkin-collector:1.25.0
-  environment:
-    - TRANSPORT_TYPE=scribe
-    - STORAGE_TYPE=mysql
-  ports:
-    - 9410:9410
-    - 9900:9900
-  links:
-    - mysql:storage
-
 query:
-  image: openzipkin/zipkin-query:1.25.0
+  image: openzipkin/zipkin-query:1.30.0
   environment:
     # Remove TRANSPORT_TYPE to disable tracing
     - TRANSPORT_TYPE=http
@@ -28,6 +17,6 @@ rabbitmq:
     - 15672
 
 mysql:
-  image: openzipkin/zipkin-mysql:1.25.0
+  image: openzipkin/zipkin-mysql:1.30.0
   ports:
-    - 3306:3306
+    - 3306:3306