自定义Filter

说明

  • 本文是说明如何进行 org.springframework.web.server.WebFliter 的扩展。

跨域支持

  • 新增 org.dromara.soul.bootstrap.cors.CrossFilter 实现 WebFilter。

    1. public class CrossFilter implements WebFilter {
    3.     private static final String ALLOWED_HEADERS = "x-requested-with, authorization, Content-Type, Authorization, credential, X-XSRF-TOKEN,token,username,client";
    5.     private static final String ALLOWED_METHODS = "*";
    7.     private static final String ALLOWED_ORIGIN = "*";
    9.     private static final String ALLOWED_EXPOSE = "*";
    11.     private static final String MAX_AGE = "18000";
    13.     @Override
    14.     @SuppressWarnings("all")
    15.     public Mono<Void> filter(final ServerWebExchange exchange, final WebFilterChain chain) {
    16.         ServerHttpRequest request = exchange.getRequest();
    17.         if (CorsUtils.isCorsRequest(request)) {
    18.             ServerHttpResponse response = exchange.getResponse();
    19.             HttpHeaders headers = response.getHeaders();
    20.             headers.add("Access-Control-Allow-Origin", ALLOWED_ORIGIN);
    21.             headers.add("Access-Control-Allow-Methods", ALLOWED_METHODS);
    22.             headers.add("Access-Control-Max-Age", MAX_AGE);
    23.             headers.add("Access-Control-Allow-Headers", ALLOWED_HEADERS);
    24.             headers.add("Access-Control-Expose-Headers", ALLOWED_EXPOSE);
    25.             headers.add("Access-Control-Allow-Credentials", "true");
    26.             if (request.getMethod() == HttpMethod.OPTIONS) {
    27.                 response.setStatusCode(HttpStatus.OK);
    28.                 return Mono.empty();
    29.             }
    30.         }
    31.         return chain.filter(exchange);
    32.     }
    33. }
  • 将 CrossFilter 注册成为 spring的bean，完事。

网关过滤 springboot健康检查

  • 注意顺序，使用 @Order 注解
  1. @Component
  2. @Order(-99)
  3. public final class HealthFilter implements WebFilter {
  5.     private static final String[] FILTER_TAG = {"/actuator/health", "/health_check"};
  7.     @Override
  8.     public Mono<Void> filter(@Nullable final ServerWebExchange exchange, @Nullable final WebFilterChain chain) {
  9.         ServerHttpRequest request = Objects.requireNonNull(exchange).getRequest();
  10.         String urlPath = request.getURI().getPath();
  11.         for (String check : FILTER_TAG) {
  12.             if (check.equals(urlPath)) {
  13.                 String result = JsonUtils.toJson(new Health.Builder().up().build());
  14.                 DataBuffer dataBuffer = exchange.getResponse().bufferFactory().wrap(result.getBytes());
  15.                 return exchange.getResponse().writeWith(Mono.just(dataBuffer));
  16.             }
  17.         }
  18.         return Objects.requireNonNull(chain).filter(exchange);
  19.     }
  20. }

继承 org.dromara.soul.web.filter.AbstractWebFilter

  • 新增一个类，继承它。

  • 实现它的2个方法。

  1.    /**
  2.      * this is Template Method ,children Implement your own filtering logic.
  3.      *
  4.      * @param exchange the current server exchange
  5.      * @param chain    provides a way to delegate to the next filter
  6.      * @return {@code Mono<Boolean>} result：TRUE (is pass)，and flow next filter；FALSE (is not pass) execute doDenyResponse(ServerWebExchange exchange)
  7.      */
  8.     protected abstract Mono<Boolean> doFilter(ServerWebExchange exchange, WebFilterChain chain);
  10.     /**
  11.      * this is Template Method ,children Implement your own And response client.
  12.      *
  13.      * @param exchange the current server exchange.
  14.      * @return {@code Mono<Void>} response msg.
  15.      */
  16.     protected abstract Mono<Void> doDenyResponse(ServerWebExchange exchange);
  • doFilter 方法返回 Monotrue 表示通过，反之则不通过，不通过的时候，会调用 doDenyResponse输出相关信息到前端。