version
spring-cloud 2021.0.1
spring-boot 2.6.3
spring-cloud-alibaba 2021.0.1.0

网关不是基于springmvc的,而是基于webflux去做的
SpringCloudGateway中Post请求参数只能读取一次
这是因为Gateway默认使用的是SpringWebflux，解决这个问题需要容重新构造一个request来替换原先的request

CacheBodyGlobalFilter这个全局过滤器把原有的request请求中的body内容读出来，并且使用ServerHttpRequestDecorator这个请求装饰器对request进行包装，重写getBody方法，并把包装后的请求放到过滤器链中传递下去。这样后面的过滤器中再使用exchange.getRequest().getBody()来获取body时，实际上就是调用的重载后的getBody方法，获取的最先已经缓存了的body数据。这样就能够实现body的多次读取了。
//过滤器的Ordered.HIGHEST_PRECEDENCE，即最高优先级的过滤器。优先级设置高的原因是某些系统内置的过滤器可能也会去读body。

Request log

@Configuration
public class RequestLogGlobalFilter implements GlobalFilter, Ordered {

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpRequest request = exchange.getRequest();
        URI uri = request.getURI();
        //String path = request.getPath().value();
        String path = request.getPath().pathWithinApplication().value();//打印请求路径
        String requestUrl = this.getOriginalRequestUrl(exchange);//打印请求url
        String method = request.getMethodValue();
        //cors
        HttpHeaders headers = request.getHeaders();
        
        log.info("--> method: {} url: {} header: {}", method, requestUrl, headers);
        if ("POST".equals(method)) {
            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("--> {}", bodyString);
                        //log.info("--> {}", formatStr(bodyString)); //formData
                        exchange.getAttributes().put("POST_BODY", bodyString);
                        DataBufferUtils.release(dataBuffer);
                        Flux<DataBuffer> cachedFlux = Flux.defer(() -> {
                            DataBuffer buffer = exchange.getResponse().bufferFactory().wrap(bytes);
                            return Mono.just(buffer);
                        });

                        ServerHttpRequest mutatedRequest = new ServerHttpRequestDecorator(request) {
                            @Override
                            public Flux<DataBuffer> getBody() {
                                return cachedFlux;
                            }
                        };
                        //log.info("****************************************************************************\n");
                        return chain.filter(exchange.mutate().request(mutatedRequest).build());
                    });
        } else if ("GET".equals(method)) {
            MultiValueMap<String, String> queryParams = request.getQueryParams();
            log.info("请求参数：" + queryParams);
            //log.info("****************************************************************************\n");
            return chain.filter(exchange);
        }
        return chain.filter(exchange);
    }

    private String getOriginalRequestUrl(ServerWebExchange exchange) {
        ServerHttpRequest req = exchange.getRequest();
        LinkedHashSet<URI> uris = exchange.getRequiredAttribute(ServerWebExchangeUtils.GATEWAY_ORIGINAL_REQUEST_URL_ATTR);
        URI requestUri = uris.stream().findFirst().orElse(req.getURI());
        MultiValueMap<String, String> queryParams = req.getQueryParams();
        //打印 /api/rest/feign/order/detail
        // return UriComponentsBuilder.fromPath(requestUri.getRawPath()).queryParams(queryParams).build().toUriString();

        return requestUri.toString(); // http://localhost:8091/api/rest/feign/order/detail
    }

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

    /**
     * 去掉FormData 空格,换行和制表符
     * @param str
     * @return
     */
    private static String formatStr(String str){
        if (str != null && str.length() > 0) {
            Pattern p = Pattern.compile("\\s*|\t|\r|\n");
            Matcher m = p.matcher(str);
            return m.replaceAll("");
        }
        return str;
    }

}

Response log

@Configuration
public class ResponseLogGlobalFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        try {
            ServerHttpResponse originalResponse = exchange.getResponse();
            DataBufferFactory bufferFactory = originalResponse.bufferFactory();

            HttpStatus statusCode = originalResponse.getStatusCode();

            if(statusCode == HttpStatus.OK){
                ServerHttpResponseDecorator decoratedResponse = new ServerHttpResponseDecorator(originalResponse) {

                    @Override
                    public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                        //log.info("body instanceof Flux: {}", (body instanceof Flux));
                        if (body instanceof Flux) {
                            Flux<? extends DataBuffer> fluxBody = Flux.from(body);
                            //
                            return super.writeWith(fluxBody.map(dataBuffer -> {
                                byte[] content = new byte[dataBuffer.readableByteCount()];
                                dataBuffer.read(content);
                                DataBufferUtils.release(dataBuffer);//释放掉内存
                                // 构建日志
                                StringBuilder sb2 = new StringBuilder(200);
                                sb2.append("<--- {} {} \n");
                                List<Object> rspArgs = new ArrayList<>();
                                rspArgs.add(originalResponse.getStatusCode());
                                //rspArgs.add(requestUrl);
                                String data = new String(content, StandardCharsets.UTF_8);//data
                                sb2.append(data);
                                log.info(sb2.toString(), rspArgs.toArray());//log.info("<-- {} {}\n", originalResponse.getStatusCode(), data);
                                return bufferFactory.wrap(content);
                            }));
                        } else {
                            log.error("<--- {} 响应code异常", getStatusCode());
                        }
                        return super.writeWith(body);
                    }
                };
                return chain.filter(exchange.mutate().response(decoratedResponse).build());
            }
            return chain.filter(exchange);//降级处理返回数据
        }catch (Exception e){
            log.error("gateway log exception.\n" + e);
            return chain.filter(exchange);
        }
    }

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

CorsWebFilterConfig 跨域配置

Gateway跨域处理
https://blog.csdn.net/weixin_43730516/article/details/127040628

@Configuration
public class CorsWebFilterConfig {
    @Bean
    public CorsWebFilter corsWebFilter() {
        CorsConfigurationSource corsConfigurationSource = new CorsConfigurationSource() {
            @Override
            public CorsConfiguration getCorsConfiguration(ServerWebExchange serverWebExchange) {
                CorsConfiguration corsConfig = new CorsConfiguration();
                corsConfig.addAllowedHeader("*");
                corsConfig.addAllowedMethod("*");
                corsConfig.addAllowedOriginPattern("*");
                corsConfig.setMaxAge(1800L);
                corsConfig.setAllowCredentials(true);
                return corsConfig;
            }
        };
        return new CorsWebFilter(corsConfigurationSource);
} }

SpringCloud Gateway 请求响应日志打印

参考资料
SpringCloud Gateway 打印请求和响应信息
https://blog.csdn.net/liben0429/article/details/126106528

Gateway网关日志
https://blog.csdn.net/small_to_large/article/details/125326498
原文链接：https://blog.csdn.net/sowei2009/article/details/126104934

https://www.jb51.net/article/240256.htm
https://blog.csdn.net/chaojunma/article/details/122595612

http://t.zoukankan.com/lifengdi-p-12524092.html

https://www.51ufo.cn/%E5%88%86%E5%B8%83%E5%BC%8F/2021/12/23/SpringCloud-Gateway%E7%BD%91%E5%85%B3%E6%94%B6%E9%9B%86%E8%AF%B7%E6%B1%82%E6%97%A5%E5%BF%97.html

乱码问题处理
https://blog.csdn.net/qq_38380025/article/details/100032490

https://www.icode9.com/content-4-1302983.html

其它

globalcors

spring:
  cloud:
    gateway:
      default-filters: #全局用于配置所有路由共享过滤器
        - PreserveHostHeader #发送原主机头
      globalcors:
        cors-configurations:
          '[/**]': # 匹配所有请求
            allowedOrigins: "*" #跨域处理 允许所有的域
            allowedMethods: # 支持的方法
              - GET
              - POST
              - PUT
              - DELETE
      routes:
        - id: product_route
          uri: http://192.168.0.101:8080
          order: 1
          predicates:
            - Path=/**