作为网关，日志记录是必不可少的功能，可以在网关出增加requestId来查询整个请求链的调用执行情况等等。
打印请求日志打印请求日志最重要的就是打印请求参数这些东西，不过RequestBody通常情况下在被读取一次之后就会失效，这样的话，下游的服务就不能正常获取到请求参数了。所以我们需要重写下请求体。
具体方法呢有很多，这里说一下我用的两种：
第一种代码如下：
package com.lifengdi.gateway.filter; import com.lifengdi.gateway.constant.HeaderConstant; import com.lifengdi.gateway.constant.OrderedConstant; import com.lifengdi.gateway.log.Log; import com.lifengdi.gateway.log.LogHelper; import com.lifengdi.gateway.utils.GenerateIdUtils; import com.lifengdi.gateway.utils.IpUtils; import io.netty.buffer.UnpooledByteBufAllocator; import lombok.extern.slf4j.Slf4j; import org.apache.commons.lang.StringUtils; 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.NettyDataBufferFactory; 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.stereotype.Component; import org.springframework.util.StopWatch; import org.springframework.web.reactive.function.server.HandlerStrategies; import org.springframework.web.reactive.function.server.ServerRequest; import org.springframework.web.server.ServerWebExchange; import reactor.core.publisher.Flux; import reactor.core.publisher.Mono; import java.net.URI; import java.util.Objects; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicReference; import java.util.function.Consumer; /** * 请求日志打印 */ @Component @Slf4j public class RequestLogFilter implements GlobalFilter, Ordered { @Override public int getOrder() { return OrderedConstant.REQUEST_FILTER; } @Override public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) { StopWatch stopWatch = new StopWatch(); stopWatch.start(); long startTime = System.currentTimeMillis(); try { ServerHttpRequest request = exchange.getRequest(); // 设置X-Request-Id AtomicReference<String> requestId = new AtomicReference<>(GenerateIdUtils.requestIdWithUUID()); Consumer<HttpHeaders> httpHeadersConsumer = httpHeaders -> { String headerRequestId = request.getHeaders().getFirst(HeaderConstant.REQUEST_ID); if (StringUtils.isBlank(headerRequestId)) { httpHeaders.set(HeaderConstant.REQUEST_ID, requestId.get()); } else { requestId.set(headerRequestId); } httpHeaders.set(HeaderConstant.START_TIME_KEY, String.valueOf(startTime)); }; ServerRequest serverRequest = ServerRequest.create(exchange, HandlerStrategies.withDefaults().messageReaders()); URI requestUri = request.getURI(); String uriQuery = requestUri.getQuery(); String url = requestUri.getPath() + (StringUtils.isNotBlank(uriQuery) ? "?" + uriQuery : ""); HttpHeaders headers = request.getHeaders(); MediaType mediaType = headers.getContentType(); String method = request.getMethodValue().toUpperCase(); // 原始请求体 final AtomicReference<String> requestBody = new AtomicReference<>(); final AtomicBoolean newBody = new AtomicBoolean(false); if (Objects.nonNull(mediaType) && LogHelper.isUploadFile(mediaType)) { requestBody.set("上传文件"); } else { if (method.equals("GET")) { if (StringUtils.isNotBlank(uriQuery)) { requestBody.set(uriQuery); } } else { newBody.set(true); } } final Log logDTO = new Log(); logDTO.setLevel(Log.LEVEL.INFO); logDTO.setRequestUrl(url); logDTO.setRequestBody(requestBody.get()); logDTO.setRequestMethod(method); logDTO.setRequestId(requestId.get()); logDTO.setIp(IpUtils.getClientIp(request)); ServerHttpRequest serverHttpRequest = exchange.getRequest().mutate().headers(httpHeadersConsumer).build(); ServerWebExchange build = exchange.mutate().request(serverHttpRequest).build(); return build.getSession().flatMap(webSession -> { logDTO.setSessionId(webSession.getId()); if (newBody.get() && headers.getContentLength() > 0) { Mono<String> bodyToMono = serverRequest.bodyToMono(String.class); return bodyToMono.flatMap(reqBody -> { logDTO.setRequestBody(reqBody); // 重写原始请求 ServerHttpRequestDecorator requestDecorator = new ServerHttpRequestDecorator(exchange.getRequest()) { @Override public Flux<DataBuffer> getBody() { NettyDataBufferFactory nettyDataBufferFactory = new NettyDataBufferFactory(new UnpooledByteBufAllocator(false)); DataBuffer bodyDataBuffer = nettyDataBufferFactory.wrap(reqBody.getBytes()); return Flux.just(bodyDataBuffer); } }; return chain.filter(exchange.mutate() .request(requestDecorator) .build()).then(LogHelper.doRecord(logDTO)); }); } else { return chain.filter(exchange).then(LogHelper.doRecord(logDTO)); } }); } catch (Exception e) { log.error("请求日志打印出现异常", e); return chain.filter(exchange); } } }