目錄
Ribbon整合Sentinel
在我們的RestTemplate組件上添加 @SentinelRestTemplate註解
並且我們可以通過在@SentinelRestTemplate 同樣的可以指定我們的blockHandlerClass,fallbackClass blockHandler,fallback 這四個屬性
@Configuration
public class WebConfig {
@Bean
@LoadBalanced
@SentinelRestTemplate(
blockHandler = "handleException",blockHandlerClass = GlobalExceptionHandler.class,
fallback = "fallback",fallbackClass = GlobalExceptionHandler.class
)
public RestTemplate restTemplate() {
return new RestTemplate();
}
}
@Slf4j
public class GlobalExceptionHandler {
/**
* 限流後處理方法
*/
public static SentinelClientHttpResponse handleException(HttpRequest request,
byte[] body, ClientHttpRequestExecution execution, BlockException ex) {
ProductInfo productInfo = new ProductInfo();
productInfo.setProductName("被限制流量拉");
productInfo.setProductNo("-1");
ObjectMapper objectMapper = new ObjectMapper();
try {
return new SentinelClientHttpResponse(objectMapper.writeValueAsString(productInfo));
} catch (JsonProcessingException e) {
e.printStackTrace();
return null;
}
}
/**
* 熔斷後處理的方法
*/
public static SentinelClientHttpResponse fallback(HttpRequest request,
byte[] body, ClientHttpRequestExecution execution, BlockException ex) {
ProductInfo productInfo = new ProductInfo();
productInfo.setProductName("被降級拉");
productInfo.setProductNo("-1");
ObjectMapper objectMapper = new ObjectMapper();
try {
return new SentinelClientHttpResponse(objectMapper.writeValueAsString(productInfo));
} catch (JsonProcessingException e) {
e.printStackTrace();
return null;
}
}
}
添加配置
#是否開啓@SentinelRestTemplate註解
resttemplate:
sentinel:
enabled: true
OpenFeign整合我們的Sentinel
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
在我們的Feign的聲明式接口上添加fallback屬性或者 fallbackFactory屬性
/*
@FeignClient(name = "product-center",fallback = ProductCenterFeignApiWithSentinelFallback.class)
*/
/*
@FeignClient(name = "product-center",fallbackFactory = ProductCenterFeignApiWithSentielFallbackFactory.class)
*/
public interface ProductCenterFeignApiWithSentinel {
/**
* 聲明式接口,遠程調用http://product-center/selectProductInfoById/{productNo}
* @param productNo
* @return
*/
@RequestMapping("/selectProductInfoById/{productNo}")
ProductInfo selectProductInfoById(@PathVariable("productNo") String productNo);
}
feign的限流降級接口(通過fallback沒有辦法獲取到異常的)
@Component
public class ProductCenterFeignApiWithSentinelFallback implements ProductCenterFeignApiWithSentinel {
@Override
public ProductInfo selectProductInfoById(String productNo) {
ProductInfo productInfo = new ProductInfo();
productInfo.setProductName("默認商品");
return productInfo;
}
}
@Component
@Slf4j
public class ProductCenterFeignApiWithSentielFallbackFactory implements FallbackFactory<ProductCenterFeignApiWithSentinel> {
@Override
public ProductCenterFeignApiWithSentinel create(Throwable throwable) {
return new ProductCenterFeignApiWithSentinel(){
@Override
public ProductInfo selectProductInfoById(String productNo) {
ProductInfo productInfo = new ProductInfo();
if (throwable instanceof FlowException) {
log.error("流控了....{}",throwable.getMessage());
productInfo.setProductName("我是被流控的默認商品");
}else {
log.error("降級了....{}",throwable.getMessage());
productInfo.setProductName("我是被降級的默認商品");
}
return productInfo;
}
};
}
}
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