content: package cn.datax.gateway.filter;
  
  import org.apache.commons.lang3.StringUtils;
  import org.springframework.cloud.gateway.filter.GatewayFilter;
  import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
  import org.springframework.http.server.reactive.ServerHttpRequest;
  import org.springframework.stereotype.Component;
  import org.springframework.web.server.ServerWebExchange;
  
  @Component
  public class SwaggerHeaderFilter extends AbstractGatewayFilterFactory {
  
      private static final String HEADER_NAME = "X-Forwarded-Prefix";
  
      private static final String URI = "/v2/api-docs";
  
      @Override
      public GatewayFilter apply(Object config) {
          return (exchange, chain) -> {
              ServerHttpRequest request = exchange.getRequest();
              String path = request.getURI().getPath();
              if (!StringUtils.endsWithIgnoreCase(path,URI )) {
                  return chain.filter(exchange);
              }
              String basePath = path.substring(0, path.lastIndexOf(URI));
              ServerHttpRequest newRequest = request.mutate().header(HEADER_NAME, basePath).build();
              ServerWebExchange newExchange = exchange.mutate().request(newRequest).build();
              return chain.filter(newExchange);
          };
      }
  }
  