(十一)Java B2B2C o2o多用户商城 springcloud架构：服务网关Zuul高级篇

zuul:
    FormBodyWrapperFilter:
        pre:
            disable: true

public class MyFilter extends ZuulFilter {
    @Override
    String filterType() { return "pre"; //定义filter的类型，有pre、route、post、error四种  }
 
    @Override int filterOrder() { return 10; //定义filter的顺序，数字越小表示顺序越高，越先执行  }
 
    @Override boolean shouldFilter() { return true; //表示是否需要执行该filter，true表示执行，false表示不执行  }
 
    @Override
    Object run() { return null; //filter需要执行的具体操作  }
}

public class TokenFilter extends ZuulFilter { private final Logger logger = LoggerFactory.getLogger(TokenFilter.class);
 
    @Override public String filterType() { return "pre"; // 可以在请求被路由之前调用  }
 
    @Override public int filterOrder() { return 0; // filter执行顺序，通过数字指定 ,优先级为0，数字越大，优先级越低  }
 
    @Override public boolean shouldFilter() { return true;// 是否执行该过滤器，此处为true，说明需要过滤  }
 
    @Override public Object run() {
        RequestContext ctx = RequestContext.getCurrentContext();
        HttpServletRequest request = ctx.getRequest();
 
        logger.info("--->>> TokenFilter {},{}", request.getMethod(), request.getRequestURL().toString());
 
        String token = request.getParameter("token");// 获取请求的参数 if (StringUtils.isNotBlank(token)) {
            ctx.setSendZuulResponse(true); //对请求进行路由 ctx.setResponseStatusCode(200);
            ctx.set("isSuccess", true); return null;
        } else {
            ctx.setSendZuulResponse(false); //不对其进行路由 ctx.setResponseStatusCode(400);
            ctx.setResponseBody("token is empty");
            ctx.set("isSuccess", false); return null;
        }
    }
 
}

@Bean public TokenFilter tokenFilter() { return new TokenFilter();
}

public interface ZuulFallbackProvider { /** * The route this fallback will be used for.
     * @return The route the fallback will be used for. */ public String getRoute(); /** * Provides a fallback response.
     * @return The fallback response. */ public ClientHttpResponse fallbackResponse();
}

@Component public class ProducerFallback implements FallbackProvider { private final Logger logger = LoggerFactory.getLogger(FallbackProvider.class); //指定要处理的 service。  @Override public String getRoute() { return "spring-cloud-producer";
    } public ClientHttpResponse fallbackResponse() { return new ClientHttpResponse() {
            @Override public HttpStatus getStatusCode() throws IOException { return HttpStatus.OK;
            }
 
            @Override public int getRawStatusCode() throws IOException { return 200;
            }
 
            @Override public String getStatusText() throws IOException { return "OK";
            }
 
            @Override public void close() {
 
            }
 
            @Override public InputStream getBody() throws IOException { return new ByteArrayInputStream("The service is unavailable.".getBytes());
            }
 
            @Override public HttpHeaders getHeaders() {
                HttpHeaders headers = new HttpHeaders();
                headers.setContentType(MediaType.APPLICATION_JSON); return headers;
            }
        };
    }
 
    @Override public ClientHttpResponse fallbackResponse(Throwable cause) { if (cause != null && cause.getCause() != null) {
            String reason = cause.getCause().getMessage();
            logger.info("Excption {}",reason);
        } return fallbackResponse();
    }
}

hello neo，this is first messge
The service is unavailable.
...

#是否开启重试功能
zuul.retryable=true #对当前服务的重试次数
ribbon.MaxAutoRetries=2 #切换相同Server的次数
ribbon.MaxAutoRetriesNextServer=0

@RequestMapping("/hello") public String index(@RequestParam String name) {
    logger.info("request two name is "+name); try{
        Thread.sleep(1000000);
    }catch ( Exception e){
        logger.error(" hello two error",e);
    } return "hello "+name+"，this is two messge";
}

2018-01-22 19:50:32.401  INFO 19488 --- [io-9001-exec-14] o.s.c.n.z.f.route.FallbackProvider       : request two name is neo 2018-01-22 19:50:33.402  INFO 19488 --- [io-9001-exec-15] o.s.c.n.z.f.route.FallbackProvider       : request two name is neo 2018-01-22 19:50:34.404  INFO 19488 --- [io-9001-exec-16] o.s.c.n.z.f.route.FallbackProvider       : request two name is neo