《本文参考地址》

分开写法

RequestGlobalFilter.java

package com.makeit.filter;
 
import lombok.extern.slf4j.Slf4j;


import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.util.MultiValueMap;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
 
import java.net.URI;
import java.nio.charset.StandardCharsets;
 
/**
 * RequestFilter
 */
@Component
@Slf4j
public class RequestGlobalFilter implements GlobalFilter, Ordered {
 
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        URI URIPath = request.getURI();
        String path = request.getPath().value();
        String method = request.getMethodValue();
        HttpHeaders header = request.getHeaders();
        String requestParams = String.valueOf(request.getQueryParams());
        log.info("***********************************请求信息**********************************");
        log.info("URI = {}", URIPath);
        log.info("path = {}", path);
        log.info("header = {}", header);
        log.info("params = {}", requestParams);
 
 		//文件上传不做处理
        String contentType = header.getFirst("content-type");
        if (StringUtils.hasLength(contentType) && contentType.contains("multipart/form-data")) {
            return chain.filter(exchange);
        }
 
 		//获取requestBody
        if (header.getContentLength() > 0) {
            return DataBufferUtils.join(exchange.getRequest().getBody()).flatMap(dataBuffer -> {
                        byte[] bytes = new byte[dataBuffer.readableByteCount()];
                        dataBuffer.read(bytes);
                        String bodyString = new String(bytes, StandardCharsets.UTF_8);
                        log.info("requestBody = {}", bodyString);
                        exchange.getAttributes().put("POST_BODY", bodyString);
                        DataBufferUtils.release(dataBuffer);
                        Flux<DataBuffer> cachedFlux = Flux.defer(() -> Mono.just(exchange.getResponse().bufferFactory().wrap(bytes)));
 
                        ServerHttpRequest mutatedRequest = new ServerHttpRequestDecorator(exchange.getRequest()) {
                            @Override
                            public Flux<DataBuffer> getBody() {
                                return cachedFlux;
                            }
                        };
                        log.info("****************************************************************************\n");
                        return chain.filter(exchange.mutate().request(mutatedRequest).build());
                    });
        }
        log.info("****************************************************************************\n");
        return chain.filter(exchange);
    }
 
    @Override
    public int getOrder() {
        return Ordered.HIGHEST_PRECEDENCE;
    }
}

ResponseGlobalFilter.java

import lombok.extern.slf4j.Slf4j;
import org.reactivestreams.Publisher;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.core.io.buffer.DefaultDataBufferFactory;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import java.nio.charset.StandardCharsets;

/**
 * ResponseFilter
 */
@Slf4j
@Component
public class ResponseGlobalFilter implements GlobalFilter, Ordered {

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //获取response的 返回数据
        ServerHttpRequest originalRequest = exchange.getRequest();
        ServerHttpResponse originalResponse = exchange.getResponse();
        DataBufferFactory bufferFactory = originalResponse.bufferFactory();

        ServerHttpResponseDecorator decoratedResponse = new ServerHttpResponseDecorator(originalResponse) {
            @Override
            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                Flux<? extends DataBuffer> fluxBody = Flux.from(body);
                body = fluxBody.buffer().map(dataBuffers -> {
                    DataBufferFactory dataBufferFactory = new DefaultDataBufferFactory();
                    DataBuffer join = dataBufferFactory.join(dataBuffers);
                    byte[] content = new byte[join.readableByteCount()];
                    join.read(content);
                    String responseData = new String(content, StandardCharsets.UTF_8);
                    log.info("***********************************响应信息**********************************");
//                    log.info("请求内容:{}", originalRequest);
                    log.info("响应内容:{}", responseData);
                    log.info("****************************************************************************\n");
                    DataBufferUtils.release(join);
                    //修改返回内容，返回内容是JSON字符串
                    //byte[] uppedContent = responseData.getBytes();
                    //return bufferFactory.wrap(uppedContent);
                    return bufferFactory.wrap(content);
                });
                return super.writeWith(body);
            }
        };
        return chain.filter(exchange.mutate().response(decoratedResponse).build());
    }

    @Override
    public int getOrder() {
        //-1是响应写入过滤器，必须在此之前调用，因此return必须小于或等于-2。
        return -2;
    }
}

合并写法

RequestAndResponseGlobalFilter.java

@Slf4j
@Component
public class RequestGlobalFilter implements GlobalFilter, Ordered {

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        String path = request.getPath().value();
        String method = request.getMethodValue();
        HttpHeaders header = request.getHeaders();
        String requestParams = String.valueOf(request.getQueryParams());
        AtomicReference<String> requestBody = new AtomicReference<>("");
        log.info("***********************************请求信息**********************************");
        log.info("URI = {}", URIPath);
        log.info("path = {}", path);
        log.info("header = {}", header);
        log.info("requestParams = {}", requestParams);

        String contentType = header.getFirst("content-type");
        if (StringUtils.hasLength(contentType) && contentType.contains("multipart/form-data")) {
            return chain.filter(exchange);
        }

        //response返回内容
        ServerHttpResponse originalResponse = exchange.getResponse();
        DataBufferFactory bufferFactory = exchange.getResponse().bufferFactory();
        ServerHttpResponseDecorator decoratedResponse = new ServerHttpResponseDecorator(originalResponse) {
            @Override
            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                Flux<? extends DataBuffer> fluxBody = Flux.from(body);
                body = fluxBody.buffer().map(dataBuffers -> {
                    DataBufferFactory dataBufferFactory = new DefaultDataBufferFactory();
                    DataBuffer join = dataBufferFactory.join(dataBuffers);
                    byte[] content = new byte[join.readableByteCount()];
                    join.read(content);
                    String responseData = new String(content, StandardCharsets.UTF_8);
                    log.info("***********************************响应信息**********************************");
                    log.info("响应内容:{}", responseData);
                    log.info("****************************************************************************\n");
                    DataBufferUtils.release(join);
                    
                	//TODO 使用@Ansync异步方法日志入库
                	//修改返回内容，返回内容是JSON字符串，因此需要把JSON转成具体的对象再处理。
                	//R r = om.readValue(responseData, R.class);//R是统一泛型返回对象，这里因人而已，不具体介绍。
                	//String newContent = om.writeValueAsString(r);
                	//return bufferFactory.wrap(newContent.getBytes());
                	return bufferFactory.wrap(content);
                });
                return super.writeWith(body);
            }
        };
        log.info("****************************************************************************\n");

        //获取body，虽然该方法在后面，但是实际效果是在response前面
        if (header.getContentLength() > 0) {
            return DataBufferUtils.join(exchange.getRequest().getBody()).flatMap(dataBuffer -> {
                byte[] bytes = new byte[dataBuffer.readableByteCount()];
                dataBuffer.read(bytes);
                String bodyString = new String(bytes, StandardCharsets.UTF_8);
                //设置requestBody到变量，让response获取
                requestBody.set(bodyString);
                log.info("requestBody = {}", bodyString);
                exchange.getAttributes().put("POST_BODY", bodyString);
                DataBufferUtils.release(dataBuffer);
                Flux<DataBuffer> cachedFlux = Flux.defer(() -> Mono.just(exchange.getResponse().bufferFactory().wrap(bytes)));

                ServerHttpRequest mutatedRequest = new ServerHttpRequestDecorator(exchange.getRequest()) {
                    @Override
                    public Flux<DataBuffer> getBody() {
                        return cachedFlux;
                    }
                };
                return chain.filter(exchange.mutate().request(mutatedRequest).response(decoratedResponse).build());
            });
        }

        //没有获取BODY，不用处理request
        return chain.filter(exchange.mutate().response(decoratedResponse).build());
    }

    @Override
    public int getOrder() {
        return Ordered.HIGHEST_PRECEDENCE;
    }
}