Spring|Spring Cloud Gateway Hystrix fallback获取异常信息的处理 SpringCloudGatewayHystrixfallback获取

Gateway Hystrix fallback获取异常信息 gateway fallback后，需要知道请求的是哪个接口以及具体的异常信息，根据不同的请求以及异常进行不同的处理。一开始根据网上一篇博客上的做法：
pom.xml：

org.springframework.cloudspring-cloud-starter-gatewayorg.springframework.cloudspring-cloud-starter-netflix-hystrix

application.yml：

spring:cloud:gateway:discovery:locator:enabled: falselowerCaseServiceId: trueroutes:- id: auth-serveruri: lb://MS-OAUTH2-SERVERpredicates:- Path=/**default-filters:- name: Hystrixargs:name: fallbackcmdfallbackUri: forward:/fallback

然后fallback就是这样：

@RestController@Slf4jpublic class FallbackController {@RequestMapping(value = "https://www.it610.com/fallback")@ResponseStatuspublic Mono fallback(ServerWebExchange exchange, Throwable throwable) {Map result = new HashMap<>(3); ServerHttpRequest request = exchange.getRequest(); log.error("接口调用失败，URL={}", request.getPath().pathWithinApplication().value(), throwable); result.put("code", 60002); result.put("data", null); result.put("msg", "接口调用失败!"); return Mono.just(result); }}

但是测试发现，这样取出来的接口地址只是“/fallback”本身，并且没有异常信息：

Spring|Spring Cloud Gateway Hystrix fallback获取异常信息的处理

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后来我重新到HystrixGatewayFilterFactory类中去查看，发现了异常信息其实在exchange里：

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而请求的接口也通过debug找到了：

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所以将代码改成如下：

@RestController@Slf4jpublic class FallbackController {@RequestMapping(value = "https://www.it610.com/fallback")@ResponseStatuspublic Mono fallback(ServerWebExchange exchange) {Map result = new HashMap<>(3); result.put("code", 60002); result.put("data", null); Exception exception = exchange.getAttribute(ServerWebExchangeUtils.HYSTRIX_EXECUTION_EXCEPTION_ATTR); ServerWebExchange delegate = ((ServerWebExchangeDecorator) exchange).getDelegate(); log.error("接口调用失败，URL={}", delegate.getRequest().getURI(), exception); if (exception instanceof HystrixTimeoutException) {result.put("msg", "接口调用超时"); } else if (exception != null && exception.getMessage() != null) {result.put("msg", "接口调用失败: " + exception.getMessage()); } else {result.put("msg", "接口调用失败"); }return Mono.just(result); }}

正常取到请求路径以及异常信息：

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关于 hystrix 的异常 fallback method wasn't found
消费者服务--service 的实现如下：

@Servicepublic class BookService {@Autowiredpublic RestTemplaterestTemplate; @HystrixCommand(fallbackMethod = "addServiceFallback")publicBookgetBook( IntegerbookId ){returnrestTemplate.getForObject("http://provider-service/boot/book?bookId={bookId}",Book.class , bookId); }publicStringaddServiceFallback(){System.out.println("error addServiceFallback.... "); return"error" ; }}

就会出现如下所述的异常

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Fri May 25 14:27:51 CST 2018
There was an unexpected error (type=Internal Server Error, status=500).
fallback method wasn't found: addServiceFallback([class java.lang.Integer])

这是因为指定的备用方法 addServiceFallback 和原方法getBook 的参数个数，参数类型不同造成的；
修改addServiceFallback 方法：

publicString addServiceFallback(IntegerbookId){System.out.println("error addServiceFallback.... "); return"error" ; }

继续运行，就会出现如下所述的异常

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Fri May 25 14:32:24 CST 2018
There was an unexpected error (type=Internal Server Error, status=500).
Incompatible return types. Command method: public com.bmcc.springboot.model.Book com.bmcc.springboot.service.BookService.getBook(java.lang.Integer); Fallback method: public java.lang.String com.bmcc.springboot.service.BookService.addServiceFallback(java.lang.Integer); Hint: Fallback method 'public java.lang.String com.bmcc.springboot.service.BookService.addServiceFallback(java.lang.Integer)' must return: class com.bmcc.springboot.model.Book or its subclass

这是因为指定的备用方法 addServiceFallback 和原方法getBook 虽然参数个数，参数类型相同，但是方法的返回值类型不同造成的；
修改addServiceFallback 方法：