springcloud gateway 拦截获取请求参数

package com.test.gateway.filter;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.qs.gateway.filter.xss.EscapeUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.annotation.Order;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StringUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import space.tryanything.kit.security.oauth.OAuth2Key;

import java.nio.charset.StandardCharsets;
import java.util.stream.Collectors;

@Slf4j
@Component
@Order(3)
public class HttpRequestFilter implements GlobalFilter {
    private final ObjectMapper mapper = new ObjectMapper();
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        String method = request.getMethodValue().toUpperCase();
        if("GET".equalsIgnoreCase(method)){
            try {
                skyWalkInput(mapper.writeValueAsString(request.getQueryParams()),exchange);
            } catch (JsonProcessingException e) {
                log.error(e.getMessage(), e);
            }
            ServerHttpRequest mutateReq = new ServerHttpRequestDecorator(request) {
                @Override
                public MultiValueMap<String, String> getQueryParams() {
                    final MultiValueMap<String, String> parent = super.getQueryParams();
                    final MultiValueMap<String, String> now = new LinkedMultiValueMap<>(parent.size());
                    parent.forEach((key, value) -> now.addAll(key,
                            value.stream()
                                    .map(EscapeUtil::clean)
                                    .collect(Collectors.toList())));

                    return now;
                }
            };
            return chain.filter(exchange.mutate().request(mutateReq).build());
        }
        return requestDecorator(exchange,chain);
    }

    private Mono<Void> requestDecorator(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        final HttpHeaders httpHeaders = new HttpHeaders();
        httpHeaders.putAll(request.getHeaders());
        httpHeaders.remove(HttpHeaders.CONTENT_LENGTH);
        httpHeaders.set(HttpHeaders.CONTENT_TYPE,MediaType.APPLICATION_JSON_VALUE);
        return DataBufferUtils.join(request.getBody()).flatMap(dataBuffer -> {
            byte[] bytes = new byte[dataBuffer.readableByteCount()];
            dataBuffer.read(bytes);
            String bodyStr = new String(bytes, StandardCharsets.UTF_8);
            skyWalkInput(bodyStr,exchange);
            exchange.getAttributes().put("POST_BODY", bodyStr);
            DataBufferUtils.release(dataBuffer);
            Flux<DataBuffer> cachedFlux = Flux.defer(() -> {
                DataBuffer buffer = response.bufferFactory().wrap(bytes);
                return Mono.just(buffer);
            });
            ServerHttpRequest mutateReq = new ServerHttpRequestDecorator(request) {
                @Override
                public Flux<DataBuffer> getBody() {
                    return cachedFlux;
                }

            };
            return chain.filter(exchange.mutate().request(mutateReq).build());
        });
    }

    private void skyWalkInput(String body,ServerWebExchange exchange){
        //构造请求的方法&URL&参数
        StringBuilder sb = new StringBuilder("curl")
                .append(" -X ").append(exchange.getRequest().getMethod())
                .append(" ").append(exchange.getRequest().getPath().pathWithinApplication().value());
        if(StringUtils.hasLength(body)){
            sb.append("?").append(body);
        }
        //构造header
        HttpHeaders header = exchange.getRequest().getHeaders();
        String authorization = header.getFirst(OAuth2Key.AUTHORIZATION_KEY);
        sb.append(" -H '").append("authorization:").append(authorization).append("'");
        String contentType = header.getFirst(HttpHeaders.CONTENT_TYPE);
        sb.append(" -H '").append("Content-Type:").append(contentType).append("'");
    }

}