SA实战 ·《SpringCloud Alibaba实战》第14章-服务网关：SpringCloud Gateway核心技术 下

/**
 * @author binghe
 * @version 1.0.0
 * @description 接收配置文件中的参数
 */
@Data
public class NameRoutePredicateConfig implements Serializable {
    private static final long serialVersionUID = -3289515863427972825L;
    private String name;
}

/**
 * @author binghe
 * @version 1.0.0
 * @description 自定义断言功能
 */
@Component
public class NameRoutePredicateFactory extends AbstractRoutePredicateFactory<NameRoutePredicateConfig> {
    public NameRoutePredicateFactory() {
        super(NameRoutePredicateConfig.class);
    }
    @Override
    public Predicate<ServerWebExchange> apply(NameRoutePredicateConfig config) {
        return (serverWebExchange)->{
            String name = serverWebExchange.getRequest().getQueryParams().getFirst("name");
            if (StringUtils.isEmpty(name)){
                name = "";
            }
            return name.equals(config.getName());
        };
    }
    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("name");
    }
}

@GetMapping(value = "/api/filter1")
public String apiFilter1(HttpServletRequest request, HttpServletResponse response){
    log.info("访问了apiFilter1接口");
    String ip = request.getHeader("IP");
    String name = request.getParameter("name");
    log.info("ip = " + ip + ", name = " + name);
    return "apiFilter1";
}

/**
 * @author binghe
 * @version 1.0.0
 * @description 接收配置参数
 */
@Data
public class GrayscaleGatewayFilterConfig implements Serializable {
    private static final long serialVersionUID = 983019309000445082L;
    private boolean grayscale;
}

/**
 * @author binghe
 * @version 1.0.0
 * @description 自定义过滤器模拟实现灰度发布
 */
@Component
public class GrayscaleGatewayFilterFactory extends AbstractGatewayFilterFactory<GrayscaleGatewayFilterConfig> {
    public GrayscaleGatewayFilterFactory(){
        super(GrayscaleGatewayFilterConfig.class);
    }
    @Override
    public GatewayFilter apply(GrayscaleGatewayFilterConfig config) {
        return (exchange, chain) -> {
            if (config.isGrayscale()){
                System.out.println("开启了灰度发布功能...");
            }else{
                System.out.println("关闭了灰度发布功能...");
            }
            return chain.filter(exchange);
        };
    }
    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("grayscale");
    }
}

/**
 * @author binghe
 * @version 1.0.0
 * @description 网关过滤器配置
 */
@Configuration
@Slf4j
public class GatewayFilterConfig {
    @Bean
    @Order(-1)
    public GlobalFilter globalFilter() {
        return (exchange, chain) -> {
            log.info("执行前置过滤器逻辑");
            return chain.filter(exchange).then(Mono.fromRunnable(() -> {
                log.info("执行后置过滤器逻辑");
            }));
        };
    }
}

/**
 * @author binghe
 * @version 1.0.0
 * @description 自定义全局过滤器，模拟实现获取客户端信息并统计接口访问时长
 */
@Slf4j
@Component
public class GlobalGatewayLogFilter implements GlobalFilter, Ordered {
    /**
     * 开始访问时间
     */
    private static final String BEGIN_VISIT_TIME = "begin_visit_time";
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //先记录下访问接口的开始时间
        exchange.getAttributes().put(BEGIN_VISIT_TIME, System.currentTimeMillis());
        return chain.filter(exchange).then(Mono.fromRunnable(()->{
            Long beginVisitTime = exchange.getAttribute(BEGIN_VISIT_TIME);
            if (beginVisitTime != null){
                log.info("访问接口主机: " + exchange.getRequest().getURI().getHost());
                log.info("访问接口端口: " + exchange.getRequest().getURI().getPort());
                log.info("访问接口URL: " + exchange.getRequest().getURI().getPath());
                log.info("访问接口URL参数: " + exchange.getRequest().getURI().getRawQuery());
                log.info("访问接口时长: " + (System.currentTimeMillis() - beginVisitTime) + "ms");
            }
        }));
    }
    @Override
    public int getOrder() {
        return 0;
    }
}