并且资源，《PPS33A》幑与重试配置不同的是，通过系列前面的源码分析，我们知道 spring-cloud-openfeign 的 FeignClient 其实是懒加载的。所以我们实现的断路器也是懒加载的，需要先调用，之后才会初始化断路器。所以这里我们需要先进行调用之后，再验证断路器配置。
首先定义两个 FeignClient，微服务分别是 testService1 和 testService2，contextId 分别是 testService1Client 和 testService2Client
@FeignClient(name = "testService1", contextId = "testService1Client")
public interface TestService1Client {
@GetMapping("/anything")
HttpBinAnythingResponse anything();
}
@FeignClient(name = "testService2", contextId = "testService2Client")
public interface TestService2Client {
@GetMapping("/anything")
HttpBinAnythingResponse anything();
}
然后，我们增加 Spring 配置，并且给两个微服务都添加一个实例，使用 SpringExtension 编写单元测试类：
//SpringExtension也包含了 Mockito 相关的 Extension，所以 @Mock 等注解也生效了
@ExtendWith(SpringExtension.class)
@SpringBootTest(properties = {
//默认请求重试次数为 3
"resilience4j.retry.configs.default.maxAttempts=3",
// testService2Client 里面的所有方法请求重试次数为 2
"resilience4j.retry.configs.testService2Client.maxAttempts=2",
//默认断路器配置
"resilience4j.circuitbreaker.configs.default.slidingWindowSize=5",
"resilience4j.circuitbreaker.configs.default.minimumNumberOfCalls=2",
//testService2Client 的 断路器配置
"resilience4j.circuitbreaker.configs.testService2Client.failureRateThreshold=30",
"resilience4j.circuitbreaker.configs.testService2Client.minimumNumberOfCalls=10",
})
@Log4j2
public class OpenFeignClientTest {
@SpringBootapplication
@Configuration
public static class app {
@Bean
public DiscoveryClient discoveryClient() {
//模拟两个服务实例
ServiceInstance service1Instance1 = Mockito.spy(ServiceInstance.class);
ServiceInstance service2Instance2 = Mockito.spy(ServiceInstance.class);
Map<String, String> zone1 = Map.ofEntries(
Map.entry("zone", "zone1")
);
when(service1Instance1.getMetadata()).thenReturn(zone1);
when(service1Instance1.getInstanceId()).thenReturn("service1Instance1");
when(service1Instance1.getHost()).thenReturn("www.httpbin.org");
when(service1Instance1.getPort()).thenReturn(80);
when(service2Instance2.getInstanceId()).thenReturn("service1Instance2");
when(service2Instance2.getHost()).thenReturn("httpbin.org");
when(service2Instance2.getPort()).thenReturn(80);
DiscoveryClient spy = Mockito.spy(DiscoveryClient.class);
Mockito.when(spy.getInstances("testService1"))
.thenReturn(List.of(service1Instance1));
Mockito.when(spy.getInstances("testService2"))
.thenReturn(List.of(service2Instance2));
return spy;
}
}
}
编写测试代码，验证配置正确：
@Test
public void testConfigureCircuitBreaker() {
//防止断路器影响
circuitBreakerRegistry.getAllCircuitBreakers().asJava().forEach(CircuitBreaker::reset);
//调用下这两个 FeignClient 确保对应的 NamedContext 被初始化
testService1Client.anything();
testService2Client.anything();
//验证断路器的实际配置，符合我们的填入的配置
List<CircuitBreaker> circuitBreakers = circuitBreakerRegistry.getAllCircuitBreakers().asJava();
Set<String> collect = circuitBreakers.stream().map(CircuitBreaker::getName)
.filter(name -> {
try {
return name.contains(TestService1Client.class.getMethod("anything").toGenericString())
|| name.contains(TestService2Client.class.getMethod("anything").toGenericString());
} catch (NoSuchMethodException e) {
return false;
}
}).collect(Collectors.toSet());
Assertions.assertEquals(collect.size(), 2);
circuitBreakers.forEach(circuitBreaker -> {
if (circuitBreaker.getName().contains(TestService1Client.class.getName())) {
Assertions.assertEquals((int) circuitBreaker.getCircuitBreakerConfig().getFailureRateThreshold(), (int) DEFAULT_FAILURE_RATE_THRESHOLD);
Assertions.assertEquals(circuitBreaker.getCircuitBreakerConfig().getMinimumNumberOfCalls(), DEFAULT_MINIMUM_NUMBER_OF_CALLS);
} else if (circuitBreaker.getName().contains(TestService2Client.class.getName())) {
Assertions.assertEquals((int) circuitBreaker.getCircuitBreakerConfig().getFailureRateThreshold(), (int) TEST_SERVICE_2_FAILURE_RATE_THRESHOLD);
Assertions.assertEquals(circuitBreaker.getCircuitBreakerConfig().getMinimumNumberOfCalls(), TEST_SERVICE_2_MINIMUM_NUMBER_OF_CALLS);
}
});
}
验证断路器是基于服务和方法打开的。
我们给 TestService1Client 添加一个方法：
@GetMapping("/status/500")
String testCircuitBreakerStatus500();
这个方法一定会调用失败，从而导致断路器打开。经过 2 次失败以上后(因为配置最少触发断路器打开的请求个数为 2)，验证断路器状态：
@Test
public void testCircuitBreakerOpenBasedOnServiceAndMethod() {
//防止断路器影响
circuitBreakerRegistry.getAllCircuitBreakers().asJava().forEach(CircuitBreaker::reset);
AtomicBoolean passed = new AtomicBoolean(false);
for (int i = 0; i < 10; i++) {
//多次调用会导致断路器打开
try {
System.out.println(testService1Client.testCircuitBreakerStatus500());
} catch(Exception e) {}
List<CircuitBreaker> circuitBreakers = circuitBreakerRegistry.getAllCircuitBreakers().asJava();
circuitBreakers.stream().filter(circuitBreaker -> {
return circuitBreaker.getName().contains("testCircuitBreakerStatus500")
&& circuitBreaker.getName().contains("TestService1Client");
}).findFirst().ifPresent(circuitBreaker -> {
//验证对应微服务和方法的断路器被打开
if (circuitBreaker.getState().equals(CircuitBreaker.State.OPEN)) {
passed.set(true);
//断路器打开后，调用其他方法，不会抛出断路器打开异常
testService1Client.testAnything();
}
});
}
Assertions.assertTrue(passed.get());
}
这样，我们就成功验证了，验证断路器是基于服务和方法打开的。
