1864 do not configure trace for async mongodb (#1869)

* Do not autoconfigure Branve Mongo DB trace for async mongo db

* Fix checkstyle violations

* Add Junit to test BraveMongoDBAutoConfig for async mongo db driver

* Minor fixes

* Use JUnit 5

pom.xml

@@ -90,6 +90,7 @@
 		<awaitility.version>4.0.3</awaitility.version>
 		<brave-propagation-aws.version>0.21.3</brave-propagation-aws.version>
 		<archunit-junit5.version>0.14.1</archunit-junit5.version>
+		<mongodb-driver-reactivestreams.version>4.0.0</mongodb-driver-reactivestreams.version>
 	</properties>
 
 	<build>
@@ -277,6 +278,11 @@
 				<artifactId>archunit-junit5</artifactId>
 				<version>${archunit-junit5.version}</version>
 			</dependency>
+			<dependency>
+				<groupId>org.mongodb</groupId>
+				<artifactId>mongodb-driver-reactivestreams</artifactId>
+				<version>${mongodb-driver-reactivestreams.version}</version>
+			</dependency>
 		</dependencies>
 	</dependencyManagement>
 

spring-cloud-sleuth-autoconfigure/pom.xml

@@ -375,6 +375,11 @@
 			<artifactId>awaitility</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.mongodb</groupId>
+			<artifactId>mongodb-driver-reactivestreams</artifactId>
+			<scope>test</scope>
+		</dependency>
 
 		<!-- Brave -->
 		<dependency>

spring-cloud-sleuth-autoconfigure/src/main/java/org/springframework/cloud/sleuth/autoconfig/brave/instrument/mongodb/BraveMongoDbAutoConfiguration.java

@@ -25,6 +25,7 @@ import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 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.mongo.MongoAutoConfiguration;
 import org.springframework.boot.autoconfigure.mongo.MongoClientSettingsBuilderCustomizer;
@@ -41,6 +42,7 @@ import org.springframework.context.annotation.Configuration;
  * @since 3.0.0
  */
 @Configuration(proxyBeanMethods = false)
+@ConditionalOnMissingClass("com.mongodb.reactivestreams.client.MongoClient")
 @ConditionalOnBean(Tracing.class)
 @AutoConfigureAfter(BraveAutoConfiguration.class)
 @AutoConfigureBefore(MongoAutoConfiguration.class)

spring-cloud-sleuth-autoconfigure/src/test/java/org/springframework/cloud/sleuth/autoconfig/brave/instrument/mongodb/BraveMongoDbAutoConfigurationAsyncDriverTest.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2013-2021 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
+ *
+ *      https://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.autoconfig.brave.instrument.mongodb;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.FilteredClassLoader;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+import org.springframework.cloud.sleuth.autoconfig.brave.BraveAutoConfiguration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Chintan Radia
+ */
+class BraveMongoDbAutoConfigurationAsyncDriverTest {
+
+	@Test
+	void should_not_auto_configure_brave_mongo_db() {
+		new ApplicationContextRunner()
+				.withConfiguration(
+						AutoConfigurations.of(BraveAutoConfiguration.class, BraveMongoDbAutoConfiguration.class))
+				.run(context -> assertThat(context).doesNotHaveBean(BraveMongoDbAutoConfiguration.class));
+	}
+
+	@Test
+	void should_auto_configure_brave_mongo_db() {
+		new ApplicationContextRunner()
+				.withClassLoader(new FilteredClassLoader("com.mongodb.reactivestreams.client.MongoClient"))
+				.withConfiguration(
+						AutoConfigurations.of(BraveAutoConfiguration.class, BraveMongoDbAutoConfiguration.class))
+				.run(context -> assertThat(context).hasSingleBean(BraveMongoDbAutoConfiguration.class));
+	}
+
+}
+