content: /*
   * Copyright 1999-2019 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.alibaba.csp.sentinel.adapter.spring.webflux;
  
  import java.util.Optional;
  
  import com.alibaba.csp.sentinel.EntryType;
  import com.alibaba.csp.sentinel.ResourceTypeConstants;
  import com.alibaba.csp.sentinel.adapter.reactor.ContextConfig;
  import com.alibaba.csp.sentinel.adapter.reactor.EntryConfig;
  import com.alibaba.csp.sentinel.adapter.reactor.SentinelReactorTransformer;
  import com.alibaba.csp.sentinel.adapter.spring.webflux.callback.WebFluxCallbackManager;
  import com.alibaba.csp.sentinel.util.StringUtil;
  
  import org.springframework.web.server.ServerWebExchange;
  import org.springframework.web.server.WebFilter;
  import org.springframework.web.server.WebFilterChain;
  import reactor.core.publisher.Mono;
  
  /**
   * @author Eric Zhao
   * @since 1.5.0
   */
  public class SentinelWebFluxFilter implements WebFilter {
  
      public static final String SENTINEL_SPRING_WEBFLUX_CONTEXT_NAME = "sentinel_spring_webflux_context";
  
      @Override
      public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
          // Maybe we can get the URL pattern elsewhere via:
          // exchange.getAttributeOrDefault(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE, path)
          String path = exchange.getRequest().getPath().value();
  
          String finalPath = WebFluxCallbackManager.getUrlCleaner().apply(exchange, path);
          if (StringUtil.isEmpty(finalPath)) {
              return chain.filter(exchange);
          }
          return chain.filter(exchange)
              .transform(buildSentinelTransformer(exchange, finalPath));
      }
  
      private SentinelReactorTransformer<Void> buildSentinelTransformer(ServerWebExchange exchange, String finalPath) {
          String origin = Optional.ofNullable(WebFluxCallbackManager.getRequestOriginParser())
              .map(f -> f.apply(exchange))
              .orElse(EMPTY_ORIGIN);
  
          return new SentinelReactorTransformer<>(new EntryConfig(finalPath, ResourceTypeConstants.COMMON_WEB,
              EntryType.IN, new ContextConfig(getContextName(exchange), origin)));
      }
  
      protected String getContextName(ServerWebExchange exchange){
          return SENTINEL_SPRING_WEBFLUX_CONTEXT_NAME;
      }
  
      private static final String EMPTY_ORIGIN = "";
  }
  