我编写了一个使用spring-cloud-starter-stream-rabbit的测试类，当我仅运行接收器并从Rabbitmq发送消息时，它可以工作；但是当我运行测试发送程序类时，它会发生错误：org.springframework.messaging.MessageDeliveryException: Dispatcher has no subscribers for channel，我该怎么做才能使其正确？
我的步骤：
首先，运行SpringbootApplication 其次，运行JUnit测试
spring-boot-starter-parent 2.1.3.RELEASE JDK8 Rabbitmq utf8
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.springcloud</groupId>
<artifactId>stream-hello</artifactId>
<version>1.0</version>
<name>stream-hello</name>
<description>SpringCloud Project</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
SinkReceiver.java
@EnableBinding({Sink.class})
public class SinkReceiver {
private static Logger logger = LoggerFactory.getLogger(SinkReceiver.class);
@StreamListener(Sink.INPUT)
public void receive(Object payload) {
logger.info("Received: " + payload);
}
}
StreamHelloApplication.java
@SpringBootApplication
public class StreamHelloApplication {
public static void main(String[] args) {
SpringApplication.run(StreamHelloApplication.class, args);
}
}
StreamHelloApplicationTests.java
@RunWith(SpringRunner.class)
@EnableBinding(value = {StreamHelloApplicationTests.SinkSender.class})
public class StreamHelloApplicationTests {
@Autowired
private SinkSender sinkSender;
@Test
public void sinkSenderTester() {
sinkSender.output().send(MessageBuilder.withPayload("produce a message : sinkSenderTest").build());
}
public interface SinkSender {
String OUTPUT = "input";
@Output(SinkSender.OUTPUT)
MessageChannel output();
}
}
application.properties
spring.application.name=stream-hello
#config rabbitmq
spring.rabbitmq.host=localhost
spring.rabbitmq.port=35672
spring.rabbitmq.username=admin
spring.rabbitmq.password=123456
我希望junit测试可以成功运行，但是运行会发生错误。堆栈跟踪如下：
org.springframework.messaging.MessageDeliveryException: Dispatcher has no subscribers for channel 'org.springframework.context.support.GenericApplicationContext@68ceda24.input'.; nested exception is org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers, failedMessage=GenericMessage [payload=byte[34], headers={contentType=application/json, id=fc0a6890-4945-142b-55cd-668b0d3f22ed, timestamp=1555817595975}], failedMessage=GenericMessage [payload=byte[34], headers={contentType=application/json, id=fc0a6890-4945-142b-55cd-668b0d3f22ed, timestamp=1555817595975}]
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:77)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:461)
at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:401)
at com.springcloud.StreamHelloApplicationTests.sinkSenderTester(StreamHelloApplicationTests.java:21)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)
at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)
Caused by: org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers, failedMessage=GenericMessage [payload=byte[34], headers={contentType=application/json, id=fc0a6890-4945-142b-55cd-668b0d3f22ed, timestamp=1555817595975}]
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:138)
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:105)
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73)
... 34 more
答案 0 :(得分：0)
您的绑定接口SinkSender未绑定任何东西。创建了“输入”通道，但没有订阅者。而且您的SinkReceiver甚至都不是测试的一部分。
要进行测试，请阅读用户手册的Testing，尤其是新的test binder。上面的部分还包含完整的工作示例。