(十一)JAVA springboot ssm b2b2c多使用者商城系統原始碼：服務閘道器Zuul高階篇

zuul:
    FormBodyWrapperFilter:
        pre:
            disable: true複製程式碼

public class MyFilter extends ZuulFilter {
    @Override
    String filterType() {
        return "pre"; //定義filter的型別，有pre、route、post、error四種
    }
 
    @Override
    int filterOrder() {
        return 10; //定義filter的順序，數字越小表示順序越高，越先執行
    }
 
    @Override
    boolean shouldFilter() {
        return true; //表示是否需要執行該filter，true表示執行，false表示不執行
    }
 
    @Override
    Object run() {
        return null; //filter需要執行的具體操作
    }
}複製程式碼

public class TokenFilter extends ZuulFilter {
 
    private final Logger logger = LoggerFactory.getLogger(TokenFilter.class);
 
    @Override
    public String filterType() {
        return "pre"; // 可以在請求被路由之前呼叫
    }
 
    @Override
    public int filterOrder() {
        return 0; // filter執行順序，通過數字指定 ,優先順序為0，數字越大，優先順序越低
    }
 
    @Override
    public boolean shouldFilter() {
        return true;// 是否執行該過濾器，此處為true，說明需要過濾
    }
 
    @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");// 獲取請求的引數
 
        if (StringUtils.isNotBlank(token)) {
            ctx.setSendZuulResponse(true); //對請求進行路由
            ctx.setResponseStatusCode(200);
            ctx.set("isSuccess", true);
            return null;
        } else {
            ctx.setSendZuulResponse(false); //不對其進行路由
            ctx.setResponseStatusCode(400);
            ctx.setResponseBody("token is empty");
            ctx.set("isSuccess", false);
            return null;
        }
    }
 
}複製程式碼

@Bean
public TokenFilter tokenFilter() {
    return new TokenFilter();
}複製程式碼

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();
}複製程式碼

@Component
public class ProducerFallback implements FallbackProvider {
    private final Logger logger = LoggerFactory.getLogger(FallbackProvider.class);
 
    //指定要處理的 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();
    }
}複製程式碼

hello neo，this is first messge
The service is unavailable.
...複製程式碼

#是否開啟重試功能
zuul.retryable=true
#對當前服務的重試次數
ribbon.MaxAutoRetries=2
#切換相同Server的次數
ribbon.MaxAutoRetriesNextServer=0複製程式碼

@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";
}複製程式碼

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複製程式碼