Merge branch '2.1.x'

spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/reactor/SpanSubscriptionProvider.java

@@ -73,7 +73,17 @@ final class SpanSubscriptionProvider<T> implements Supplier<SpanSubscription<T>>
 
 	private Tracing tracing() {
 		if (this.tracing == null) {
-			this.tracing = this.beanFactory.getBean(Tracing.class);
+			try {
+				this.tracing = this.beanFactory.getBean(Tracing.class);
+			}
+			catch (Exception ex) {
+				if (log.isDebugEnabled()) {
+					log.debug(
+							"Exception occurred while trying to get the tracing bean. Will return a default instance",
+							ex);
+				}
+				return Tracing.newBuilder().build();
+			}
 		}
 		return this.tracing;
 	}

spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/reactor/SpanSubscriptionProviderTests.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2013-2019 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.instrument.reactor;
+
+import org.assertj.core.api.BDDAssertions;
+import org.junit.Test;
+import org.mockito.BDDMockito;
+import reactor.util.context.Context;
+
+import org.springframework.beans.factory.BeanFactory;
+
+public class SpanSubscriptionProviderTests {
+
+	@Test
+	public void should_return_default_tracing_instance_when_exception_thrown_upon_bean_retrieval() {
+		BeanFactory beanFactory = BDDMockito.mock(BeanFactory.class);
+		BDDMockito.when(beanFactory.getBean(BDDMockito.any(Class.class)))
+				.thenThrow(new IllegalStateException());
+		SpanSubscriptionProvider provider = new SpanSubscriptionProvider(beanFactory,
+				null, Context.empty(), "example");
+
+		SpanSubscription spanSubscription = provider.get();
+
+		BDDAssertions.then(spanSubscription).isNotNull();
+	}
+
+}