Why is brave.Tracer not autowired? - spring-boot

Question

We have a lot of services using Spring Boot 2.0.x and io.zipkin.brave.Tracer is used and it works properly. Tracer is used in a class annotated with #Component and it has a constructor with Tracer as its parameter.
Here's an example snippet:
#Component
public class CrmMessagePublisher {
private static final Logger LOGGER = LoggerFactory.getLogger(CrmMessagePublisher.class);
private static final String EVENT_NAME_HEADER = "service.eventName";
private static final String EXCHANGE_EVENT = "service.event";
private static String applicationName;
private RabbitTemplate rabbitTemplate;
#Autowired
private Tracer tracer;
#Autowired
public CrmMessagePublisher(
RabbitTemplate rabbitTemplate,
#Value("${spring.application.name}") final String applicationName,
Tracer tracer
) {
this.rabbitTemplate = rabbitTemplate;
CrmMessagePublisher.applicationName = applicationName;
this.tracer = tracer;
}
...
Now I want to write a junit test but I always get
Test ignored.
java.lang.IllegalStateException: Failed to load ApplicationContext
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:125)
at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:108)
at org.springframework.test.context.web.ServletTestExecutionListener.setUpRequestContextIfNecessary(ServletTestExecutionListener.java:190)
at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:132)
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:246)
at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:97)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$invokeTestInstancePostProcessors$5(ClassTestDescriptor.java:349)
at org.junit.jupiter.engine.descriptor.JupiterTestDescriptor.executeAndMaskThrowable(JupiterTestDescriptor.java:215)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$invokeTestInstancePostProcessors$6(ClassTestDescriptor.java:349)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1621)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
at java.base/java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312)
at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:735)
at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:658)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.invokeTestInstancePostProcessors(ClassTestDescriptor.java:348)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.instantiateAndPostProcessTestInstance(ClassTestDescriptor.java:270)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$2(ClassTestDescriptor.java:259)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$3(ClassTestDescriptor.java:263)
at java.base/java.util.Optional.orElseGet(Optional.java:362)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$testInstanceProvider$4(ClassTestDescriptor.java:262)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.lambda$before$0(ClassTestDescriptor.java:192)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.before(ClassTestDescriptor.java:191)
at org.junit.jupiter.engine.descriptor.ClassTestDescriptor.before(ClassTestDescriptor.java:74)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$4(NodeTestTask.java:105)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:98)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:74)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$4(NodeTestTask.java:112)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:72)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:98)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:74)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220)
at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188)
at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'crmMessagePublisher': Unsatisfied dependency expressed through constructor parameter 2; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'brave.Tracer' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1341)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1187)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:847)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:744)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:391)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:312)
at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:120)
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99)
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:117)
... 48 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'brave.Tracer' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1662)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1221)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1175)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
... 66 more
Here's the test class:
//#ExtendWith(SpringExtension.class)
#WebAppConfiguration
#ContextConfiguration(classes = {RabbitMqTest2.RabbitTestConfig.class, CrmMessagePublisher.class, Tracer.class})
////#EnableRabbit
#SpringBootTest
#TestPropertySource("classpath:application.properties")
#TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class RabbitMqTest2 {
private final String QUEUE_NAME = "crm-test-service";
#Autowired
CachingConnectionFactory connectionFactory;
#Autowired
private RabbitTemplate rabbitTemplate;
private RabbitAdmin rabbitAdmin;
private Binding binding;
private Queue queue;
#Autowired
private CrmMessagePublisher publisher;
// private Tracer tracer;
#BeforeAll
void beforeAll() {
rabbitAdmin = new RabbitAdmin(this.connectionFactory);
}
#BeforeEach
void beforeEachTestCase() {
// TODO: Get values from test configuration
connectionFactory.setUsername("admin");
connectionFactory.setPassword("admin");
connectionFactory.setHost("localhost");
connectionFactory.setPort(5672);
rabbitTemplate = new RabbitTemplate(connectionFactory);
rabbitTemplate.setDefaultReceiveQueue(QUEUE_NAME); // for receiving messages
rabbitTemplate.setRoutingKey(QUEUE_NAME); // for sending messages
Properties queueProps = rabbitAdmin.getQueueProperties(QUEUE_NAME);
if( queueProps == null ) {
queue = new Queue(QUEUE_NAME, false, false, true);
rabbitAdmin.declareQueue(queue);
binding = BindingBuilder.bind(queue).to(new FanoutExchange("service.event"));
rabbitAdmin.declareBinding(binding);
}
queueProps = rabbitAdmin.getQueueProperties(QUEUE_NAME);
Assert.assertEquals("More messages than expected are in the queue.", 0,
Integer.parseInt(queueProps.getProperty("QUEUE_MESSAGE_COUNT") == null ? "0" : queueProps.getProperty("QUEUE_MESSAGE_COUNT")));
}
#AfterEach
void afterEachTestCase() {
rabbitAdmin.removeBinding(binding);
rabbitAdmin.deleteQueue(QUEUE_NAME);
}
#Test
void sendMessageToQueue() throws JsonProcessingException {
final CrmMessageModel message = new CrmMessageModel();
message.setCustomerId(1L);
final AmqpAdmin rabbitAdmin = new RabbitAdmin(this.rabbitTemplate.getConnectionFactory());
final ObjectMapper om = new ObjectMapper();
rabbitTemplate.convertAndSend("service.event", "contract-service", om.writeValueAsString(message));
final Properties queueProps = rabbitAdmin.getQueueProperties(QUEUE_NAME);
Assert.assertEquals("Not exactly ONE message is in the queue.", 1,
Integer.parseInt(queueProps.get("QUEUE_MESSAGE_COUNT").toString()));
}
#Configuration
public static class RabbitTestConfig extends ResourceServerConfigurerAdapter {
#Bean
public CachingConnectionFactory connectionFactory() {
return new CachingConnectionFactory();
}
#Bean
public RabbitTemplate crmRabbitTemplate() {
return new RabbitTemplate(connectionFactory());
}
#Bean
public RestTemplate crmRestTemplate() {
return new RestTemplate();
}
}
}
So: What do I have to do to run the test successful?

Answer 1

I hit the same problem; fixed it by ensuring that spring.sleuth.enabled=true when running tests.

Answer 2

Please try change your testing class line from:
#ContextConfiguration(classes = {RabbitMqTest2.RabbitTestConfig.class, CrmMessagePublisher.class, Tracer.class})
to
#ContextConfiguration(classes = {RabbitMqTest2.RabbitTestConfig.class, CrmMessagePublisher.class, TraceAutoConfiguration.class})

Answer 3

The problem is that the tracer Tracer.class in your #ContextConfiguration does actually nothing:
it's not a #Configuration class
it does not have a constructor with arguments, which spring could somehow autowire
You should use org.springframework.cloud.sleuth.autoconfig.TraceAutoConfiguration.class instead, which provides a working instance of Tracer, which could be autowired.