GateWay三大案例组件

一、局部过滤器接口耗时（LogTime）

1. 命名规则：以GatewayFilterFactory结尾
2. 编写接口耗时过滤器

@Slf4j
@Component
public class LogTimeGatewayFilterFactory extends AbstractNameValueGatewayFilterFactory {

    private static long timeSpan = 0;
    @Override
    public GatewayFilter apply(NameValueConfig config) {
        String timeSpanStr = config.getValue();
        timeSpan = Long.valueOf(timeSpanStr);
        return new GatewayFilter() {
            @Override
            public Mono<Void> filter(ServerWebExchange exchange,  GatewayFilterChain chain) {

                long startTime = System.currentTimeMillis();
                return chain.filter(exchange).then(Mono.fromRunnable(()->{
                    long endTime = System.currentTimeMillis();
                    long time =  endTime-startTime;
                    if(time >= timeSpan){
                        log.debug("{} 耗时：{}",exchange.getRequest().getURI(), time);
                    }
                }));
            }
        };
    }
}

3. 在yml文件中加入耗时时长
   

二、全局Token认证（TokenGlobalFilter）

目的是对所有进入系统的请求或相应进行统一处理

1. 创建过滤器类

@Slf4j
@Component
public class TokenFilter implements GlobalFilter, Ordered {
    @Value("${cn.smart.tokenx.key}")
    private String tokenKey;
    private static List<String> whiteList = CollUtil.newArrayList("/api/login", "/api/register");
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        URI uri = request.getURI();
        String path = uri.getPath().toLowerCase().trim();
        //排除白名单的验证
        if(whiteList.contains(path)){
            return chain.filter(exchange);
        }
        ServerHttpResponse response = exchange.getResponse();
        List<String> tokens = request.getHeaders().get("token");
        //验证的是有没有传token
        if(ObjectUtil.isEmpty(tokens)){
          log.error("请传token");
         response.setStatusCode(HttpStatus.UNAUTHORIZED);
          return response.setComplete();
        }
        String token = tokens.get(0);
        //验证的是传的token值是否为空
        if(ObjectUtil.isEmpty(token)){
            log.error("token 不能为空");
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }
        boolean b = false;
        // 验证算法，JWTValidator包含过期的验证，验证比较全面
        try {
         JWTValidator.of(token).validateAlgorithm(JWTSignerUtil.hs256(tokenKey.getBytes())).validateDate();
            b = true;
        }catch (Exception ex){
            ex.printStackTrace();
            log.error("token不正确");
        }
        if(!b){
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }
        //接着执行下面的过滤器,token还会带到下游，我们的服务还是要用我们之前的token-starter,token-starter功能只保留解析token写入Threadlocal，验证的功能不再需要
        return chain.filter(exchange);
    }
    @Override
    public int getOrder() {
        return 2;
    }
}

2. 注册全局过滤器，使用@Component注解，Spring会自动扫描并注册Bean

三、全局链路跟踪TraceId日志（TraceIdGlobalFilter）

1. 创建全局过滤器，在请求头上带入traceId参数，穿透到下游服务

@Component
@Slf4j
@Order(1)
public class TraceIdFilter implements GlobalFilter {
    private static final  String  TRACE_ID = "traceId";

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        List<String> traceIds = request.getHeaders().get(TRACE_ID);
         if(ObjUtil.isNotEmpty(traceIds)){
             return chain.filter(exchange);
         }
        String traceId = IdUtil.simpleUUID();
        //request.getHeaders().set(TRACE_ID,traceId); //ReadOnlyHttpHeaders UnsupportedOperationException
        ServerHttpRequest request2 = request.mutate().header(TRACE_ID,traceId).build();
        return chain.filter(exchange.mutate().request(request2).build());
    }

2. 下游服务使用全链路跟踪Id，配置TraceId过滤器
3. 启动类开启SercletComponentScan扫描，启动类上加一个@SercletComponentScan注解
4. 配置文件配置日志输出格式