springboot集成Sentinel

1、添加依赖

• 该版本匹配springboot 2.3.x和2.4.x

<dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-sentinel</artifactId><version>2021.1</version>
</dependency>

2、SentinelConfig配置限流规则

@Configuration
public class SentinelConfig {@Beanpublic SentinelResourceAspect sentinelResourceAspect() {return new SentinelResourceAspect();}@PostConstructprivate void initRules() {//=============================规则1=========================FlowRule rule1 = new FlowRule();rule1.setResource("rule1");//规则名称rule1.setGrade(RuleConstant.FLOW_GRADE_QPS);//如果设置0则按照线程数限流，如果设置1则按照QPS（每秒查询率）限流rule1.setCount(100);   // 每秒调用最大次数为 100 次rule1.setControlBehavior(0);//0快速失败，1预警，2排队等候rule1.setMaxQueueingTimeMs(1000);//排队超时阈值//=============================规则2=========================FlowRule rule2 = new FlowRule();rule2.setResource("rule2");rule2.setGrade(RuleConstant.FLOW_GRADE_QPS);rule2.setCount(10);   // 每秒调用最大次数为 10 次List<FlowRule> rules = new ArrayList<>();rules.add(rule1);rules.add(rule2);FlowRuleManager.loadRules(rules);}
}

3、API限流

@SentinelResource(value = "rule1", blockHandler = "poll", blockHandlerClass = SentinelHandler.class)
@ApiOperation("批量拉取消息")
@PostMapping("/poll")
public BaseResult poll(@RequestBody @Valid PollMessageRequest request){return BaseResult.success(kafkaService.poll(request));
}

4、配置handler

• handler里的方法必须用public static修饰
• handler里的方法的返回值类型必须和原方法保持一致，参数是在原参数后边加一个BlockException

public class SentinelHandler {public static BaseResult poll(PollMessageRequest request, BlockException e) {throw new BusinessException("请勿频繁操作");}
}