Testing Sentinel Circuit Breaker Integration in Spring Cloud Alibaba
This integration test suite validates the Sentinel Circuit Breaker implementation in Spring Cloud Alibaba, focusing on degradation rules and fallback behavior. The tests verify circuit breaker functionality under normal and slow response scenarios, ensuring proper fault tolerance mechanisms.
Test Coverage Overview
Implementation Analysis
Technical Details
Best Practices Demonstrated
alibaba/spring-cloud-alibaba
spring-cloud-alibaba-starters/spring-cloud-circuitbreaker-sentinel/src/test/java/com/alibaba/cloud/circuitbreaker/sentinel/SentinelCircuitBreakerIntegrationTest.java
/*
* Copyright 2013-2023 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 com.alibaba.cloud.circuitbreaker.sentinel;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import com.alibaba.csp.sentinel.slots.block.RuleConstant;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRule;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRuleManager;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.web.client.TestRestTemplate;
import org.springframework.cloud.client.circuitbreaker.CircuitBreakerFactory;
import org.springframework.cloud.client.circuitbreaker.Customizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import static org.assertj.core.api.Assertions.assertThat;
import static org.springframework.boot.test.context.SpringBootTest.WebEnvironment.RANDOM_PORT;
/**
* @author Eric Zhao
*/
@SpringBootTest(webEnvironment = RANDOM_PORT,
classes = SentinelCircuitBreakerIntegrationTest.Application.class,
properties = { "spring.cloud.discovery.client.health-indicator.enabled=false" })
public class SentinelCircuitBreakerIntegrationTest {
@Autowired
private Application.DemoControllerService service;
@Test
public void testSlow() throws Exception {
assertThat(service.slow(true)).isEqualTo("slow");
assertThat(service.slow(true)).isEqualTo("slow");
assertThat(service.slow(true)).isEqualTo("slow");
assertThat(service.slow(false)).isEqualTo("slow");
assertThat(service.slow(false)).isEqualTo("slow");
assertThat(service.slow(true)).isEqualTo("slow");
assertThat(service.slow(true)).isEqualTo("slow");
// Then in the next 10s, the fallback method should be called.
for (int i = 0; i < 5; i++) {
assertThat(service.slow(true)).isEqualTo("fallback");
Thread.sleep(1000);
}
// Try a normal request.
assertThat(service.slow(false)).isEqualTo("slow");
// Recovered.
assertThat(service.slow(true)).isEqualTo("slow");
}
@Test
public void testNormal() {
assertThat(service.normal()).isEqualTo("normal");
}
@BeforeEach
public void setUp() {
DegradeRuleManager.loadRules(new ArrayList<>());
}
@BeforeEach
public void tearDown() {
DegradeRuleManager.loadRules(new ArrayList<>());
}
@Configuration
@EnableAutoConfiguration
@RestController
protected static class Application {
@GetMapping("/slow")
public String slow(@RequestParam(required = false) Boolean slow)
throws InterruptedException {
if (slow == null || slow) {
Thread.sleep(80);
}
return "slow";
}
@GetMapping("/normal")
public String normal() {
return "normal";
}
@Bean
public Customizer<SentinelCircuitBreakerFactory> slowCustomizer() {
String slowId = "slow";
List<DegradeRule> rules = Collections.singletonList(new DegradeRule(slowId)
.setGrade(RuleConstant.DEGRADE_GRADE_RT).setCount(50)
.setSlowRatioThreshold(0.7).setMinRequestAmount(5)
.setStatIntervalMs(30000).setTimeWindow(5));
return factory -> {
factory.configure(builder -> builder.rules(rules), slowId);
factory.configureDefault(id -> new SentinelConfigBuilder()
.resourceName(id)
.rules(Collections.singletonList(new DegradeRule(id)
.setGrade(RuleConstant.DEGRADE_GRADE_EXCEPTION_COUNT)
.setCount(10).setStatIntervalMs(10000).setTimeWindow(10)))
.build());
};
}
@Service
public static class DemoControllerService {
private TestRestTemplate rest;
private CircuitBreakerFactory cbFactory;
DemoControllerService(TestRestTemplate rest,
CircuitBreakerFactory cbFactory) {
this.rest = rest;
this.cbFactory = cbFactory;
}
public String slow(boolean slow) {
return cbFactory.create("slow").run(
() -> rest.getForObject("/slow?slow=" + slow, String.class),
t -> "fallback");
}
public String normal() {
return cbFactory.create("normal").run(
() -> rest.getForObject("/normal", String.class),
t -> "fallback");
}
}
}
}