Auto-configure CompositeSpanHandler with Brave

Closes gh-32753

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/tracing/BraveAutoConfiguration.java

@@ -53,7 +53,11 @@ import io.micrometer.tracing.brave.bridge.BraveHttpClientHandler;
 import io.micrometer.tracing.brave.bridge.BraveHttpServerHandler;
 import io.micrometer.tracing.brave.bridge.BravePropagator;
 import io.micrometer.tracing.brave.bridge.BraveTracer;
+import io.micrometer.tracing.brave.bridge.CompositeSpanHandler;
 import io.micrometer.tracing.brave.bridge.W3CPropagation;
+import io.micrometer.tracing.exporter.SpanExportingPredicate;
+import io.micrometer.tracing.exporter.SpanFilter;
+import io.micrometer.tracing.exporter.SpanReporter;
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfiguration;
@@ -64,6 +68,7 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.Ordered;
 import org.springframework.core.annotation.Order;
 import org.springframework.core.env.Environment;
 
@@ -87,6 +92,15 @@ public class BraveAutoConfiguration {
 	 */
 	private static final String DEFAULT_APPLICATION_NAME = "application";
 
+	@Bean
+	@ConditionalOnMissingBean
+	@Order(Ordered.HIGHEST_PRECEDENCE)
+	CompositeSpanHandler compositeSpanHandler(ObjectProvider<SpanExportingPredicate> predicates,
+			ObjectProvider<SpanReporter> reporters, ObjectProvider<SpanFilter> filters) {
+		return new CompositeSpanHandler(predicates.orderedStream().toList(), reporters.orderedStream().toList(),
+				filters.orderedStream().toList());
+	}
+
 	@Bean
 	@ConditionalOnMissingBean
 	public Tracing braveTracing(Environment environment, List<SpanHandler> spanHandlers,

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/tracing/BraveAutoConfigurationTests.java

@@ -16,11 +16,14 @@
 
 package org.springframework.boot.actuate.autoconfigure.tracing;
 
+import java.util.Collections;
+
 import brave.Span;
 import brave.Tracer;
 import brave.Tracing;
 import brave.baggage.BaggagePropagation;
 import brave.baggage.CorrelationScopeConfig.SingleCorrelationField;
+import brave.handler.SpanHandler;
 import brave.http.HttpClientHandler;
 import brave.http.HttpClientRequest;
 import brave.http.HttpClientResponse;
@@ -37,16 +40,22 @@ import io.micrometer.tracing.brave.bridge.BraveBaggageManager;
 import io.micrometer.tracing.brave.bridge.BraveHttpClientHandler;
 import io.micrometer.tracing.brave.bridge.BraveHttpServerHandler;
 import io.micrometer.tracing.brave.bridge.BraveTracer;
+import io.micrometer.tracing.brave.bridge.CompositeSpanHandler;
 import io.micrometer.tracing.brave.bridge.W3CPropagation;
+import io.micrometer.tracing.exporter.SpanExportingPredicate;
+import io.micrometer.tracing.exporter.SpanFilter;
+import io.micrometer.tracing.exporter.SpanReporter;
 import org.assertj.core.api.InstanceOfAssertFactories;
 import org.junit.jupiter.api.Test;
 import org.mockito.Answers;
 
+import org.springframework.boot.actuate.autoconfigure.tracing.BraveAutoConfigurationTests.SpanHandlerConfiguration.AdditionalSpanHandler;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.test.context.FilteredClassLoader;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.annotation.Order;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.mock;
@@ -81,6 +90,7 @@ class BraveAutoConfigurationTests {
 			assertThat(context).hasSingleBean(BraveTracer.class);
 			assertThat(context).hasSingleBean(BraveHttpServerHandler.class);
 			assertThat(context).hasSingleBean(BraveHttpClientHandler.class);
+			assertThat(context).hasSingleBean(CompositeSpanHandler.class);
 		});
 	}
 
@@ -115,6 +125,8 @@ class BraveAutoConfigurationTests {
 			assertThat(context).hasSingleBean(HttpServerHandler.class);
 			assertThat(context).hasBean("customHttpClientHandler");
 			assertThat(context).hasSingleBean(HttpClientHandler.class);
+			assertThat(context).hasBean("customCompositeSpanHandler");
+			assertThat(context).hasSingleBean(CompositeSpanHandler.class);
 		});
 	}
 
@@ -237,6 +249,108 @@ class BraveAutoConfigurationTests {
 		});
 	}
 
+	@Test
+	@SuppressWarnings("rawtypes")
+	void compositeSpanHandlerShouldBeFirstSpanHandler() {
+		this.contextRunner.withUserConfiguration(SpanHandlerConfiguration.class).run((context) -> {
+			Tracing tracing = context.getBean(Tracing.class);
+			assertThat(tracing).extracting("tracer.spanHandler.delegate.handlers")
+					.asInstanceOf(InstanceOfAssertFactories.array(SpanHandler[].class))
+					.extracting((handler) -> (Class) handler.getClass())
+					.containsExactly(CompositeSpanHandler.class, AdditionalSpanHandler.class);
+		});
+	}
+
+	@Test
+	void compositeSpanHandlerUsesFilterPredicateAndReportersInOrder() {
+		this.contextRunner.withUserConfiguration(CompositeSpanHandlerComponentsConfiguration.class).run((context) -> {
+			CompositeSpanHandlerComponentsConfiguration components = context
+					.getBean(CompositeSpanHandlerComponentsConfiguration.class);
+			CompositeSpanHandler composite = context.getBean(CompositeSpanHandler.class);
+			assertThat(composite).extracting("spanFilters").asList().containsExactly(components.filter1,
+					components.filter2);
+			assertThat(composite).extracting("filters").asList().containsExactly(components.predicate2,
+					components.predicate1);
+			assertThat(composite).extracting("reporters").asList().containsExactly(components.reporter1,
+					components.reporter3, components.reporter2);
+		});
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class CompositeSpanHandlerComponentsConfiguration {
+
+		private final SpanFilter filter1 = mock(SpanFilter.class);
+
+		private final SpanFilter filter2 = mock(SpanFilter.class);
+
+		private final SpanExportingPredicate predicate1 = mock(SpanExportingPredicate.class);
+
+		private final SpanExportingPredicate predicate2 = mock(SpanExportingPredicate.class);
+
+		private final SpanReporter reporter1 = mock(SpanReporter.class);
+
+		private final SpanReporter reporter2 = mock(SpanReporter.class);
+
+		private final SpanReporter reporter3 = mock(SpanReporter.class);
+
+		@Bean
+		@Order(1)
+		SpanFilter filter1() {
+			return this.filter1;
+		}
+
+		@Bean
+		@Order(2)
+		SpanFilter filter2() {
+			return this.filter2;
+		}
+
+		@Bean
+		@Order(2)
+		SpanExportingPredicate predicate1() {
+			return this.predicate1;
+		}
+
+		@Bean
+		@Order(1)
+		SpanExportingPredicate predicate2() {
+			return this.predicate2;
+		}
+
+		@Bean
+		@Order(1)
+		SpanReporter reporter1() {
+			return this.reporter1;
+		}
+
+		@Bean
+		@Order(3)
+		SpanReporter reporter2() {
+			return this.reporter2;
+		}
+
+		@Bean
+		@Order(2)
+		SpanReporter reporter3() {
+			return this.reporter3;
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class SpanHandlerConfiguration {
+
+		@Bean
+		SpanHandler additionalSpanHandler() {
+			return new AdditionalSpanHandler();
+		}
+
+		static class AdditionalSpanHandler extends SpanHandler {
+
+		}
+
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	private static class CustomConfiguration {
 
@@ -302,6 +416,11 @@ class BraveAutoConfigurationTests {
 			return mock(BraveHttpClientHandler.class);
 		}
 
+		@Bean
+		CompositeSpanHandler customCompositeSpanHandler() {
+			return new CompositeSpanHandler(Collections.emptyList(), Collections.emptyList(), Collections.emptyList());
+		}
+
 	}
 
 }