Spring Cloud升级之路 – Hoxton – 5. 实现微服务调用重试[亲测有效]

resilience4j.retry:
  configs:
    default:
      maxRetryAttempts: 2
      waitDuration: 1
      retryExceptions:
        - java.lang.Exception
    service-provider2:
      maxRetryAttempts: 4

IT知识分享网

IT知识分享网//对于非返回200的接口，抛出异常
if (execute.status() != HttpStatus.OK.value()) {
    throw new ResponseWrapperException(execute.toString(), execute);
}

//配置哪些包下的FeignClient进行重试，必须含有@FeignClient注解
@Around("execution(* com.github.hashjang.hoxton..*(..)) && @within(org.springframework.cloud.openfeign.FeignClient)")
public Object feignClientWasCalled(final ProceedingJoinPoint pjp) throws Throwable {
    boolean isGet = false;
    MethodSignature signature = (MethodSignature) pjp.getSignature();
    FeignClient annotation = signature.getMethod().getDeclaringClass().getAnnotation(FeignClient.class);
    String serviceName = annotation.value();
    if (StringUtils.isBlank(serviceName)) {
        serviceName = annotation.name();
    }

    //查看是否是GET请求
    RequestMapping requestMapping = signature.getMethod().getAnnotation(RequestMapping.class);
    if (requestMapping != null &&
            (requestMapping.method().length == 0 ||
                    Arrays.asList(requestMapping.method()).contains(RequestMethod.GET))
    ) {
        isGet = true;
    }
    GetMapping getMapping = signature.getMethod().getAnnotation(GetMapping.class);
    if (getMapping != null) {
        isGet = true;
    }
    Retry retry;
    try {
        retry = retryRegistry.retry(serviceName, serviceName);
    } catch (ConfigurationNotFoundException e) {
        retry = retryRegistry.retry(serviceName);
    }
    if (!isGet) {
        //非GET请求，只有在断路器打开的情况下，才会重试
        retry = Retry.of(serviceName, RetryConfig.from(retry.getRetryConfig()).retryExceptions().retryOnException(throwable -> {
            Throwable cause = throwable.getCause();
            if (cause instanceof CallNotPermittedException) {
                //对于断路器，不区分方法，都重试，因为没有实际调用
                log.info("retry on circuit breaker is on: {}", cause.getMessage());
                return true;
            }
            return false;
        }).build());
    }
    //对于GET请求，启用重试机制
    Supplier<Object> objectSupplier = Retry.decorateSupplier(retry, () -> {
        try {
            return pjp.proceed();
        } catch (Throwable throwable) {
            ReflectionUtils.rethrowRuntimeException(throwable);
            return null;
        }
    });
    return Try.ofSupplier(objectSupplier).get();
}

IT知识分享网@Data
@ConfigurationProperties(prefix = "spring.cloud.gateway")
public class ApiGatewayRetryConfig {
    private Map<String, RetryGatewayFilterFactory.RetryConfig> retry;

    public RetryGatewayFilterFactory.RetryConfig getDefault() {
        return retry.computeIfAbsent("default", key -> new RetryGatewayFilterFactory.RetryConfig());
    }
}

spring:
  cloud:
    gateway:
      # 这是我们自定义的重试配置：ApiGatewayRetryConfig,
      retry:
        default:
          retries: 1
          series: SERVER_ERROR,CLIENT_ERROR
          methods: GET
          # 对于断路器打开也会重试
          exceptions: io.github.resilience4j.circuitbreaker.CallNotPermittedException, org.springframework.cloud.gateway.support.TimeoutException, java.io.IOException
          backoff:
            basedOnPreviousValue: true
            factor: 2
            firstBackoff: 100ms
            maxBackoff: 500ms