【跪求解答】如何从Spring Cloud Gateway中的ServerWebExchange中获取原始响应并重写

Question

各位大佬们，请问下有比较了解spring cloud gateway吗，小弟我想知道怎么从ServerWebExchange中取到接口原始的响应信息，重写后再返回给调用方。实在找不到相关的解决办法，求助了！！！！我的需求是这样的，获取到接口原始的响应信息，自己再封装一层，形成统一的返回格式，然后再返回给调用方。

Answer 1

例如：原始接口返回的响应为：{“code”:200,”data”:”success”} 的字符串从spring cloud gateway中拿到的响应对象是这个：HttpClientResponse clientResponse = exchange.getAttribute(ServerWebExchangeUtils.CLIENT_RESPONSE_ATTR);如何从clientResponse中取到原始返回的json字符串

Answer 2

@Bean
  public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
    return builder.routes()
      .route("format", r -> r.path("")
        .filters(f -> f.filter(
// 这个lambda最好定义个filter类new一个filter对象或者注入bean
          (exchange, chain) -> chain.filter(exchange)
            .then(Mono.fromRunnable(() -> {
// 获取到response 可以对响应体进行重写。
                ServerHttpResponse response = exchange.getResponse();
              })
            )
          )
        ).uri("")
      )
      .build();
  }

Answer 3

看我注释，那个s就是返回的值@Component
public class WrapperResponseGlobalFilter implements GlobalFilter, Ordered {
    @Override
    public int getOrder() {
        // -1 is response write filter, must be called before that
        return -2;
    }    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpResponse originalResponse = exchange.getResponse();
        DataBufferFactory bufferFactory = originalResponse.bufferFactory();
        ServerHttpResponseDecorator decoratedResponse = new ServerHttpResponseDecorator(originalResponse) {
            @Override
            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                if (body instanceof Flux) {
                    Flux<? extends DataBuffer> fluxBody = (Flux<? extends DataBuffer>) body;
                    return super.writeWith(fluxBody.map(dataBuffer -> {
                        // probably should reuse buffers
                        byte[] content = new byte[dataBuffer.readableByteCount()];
                        dataBuffer.read(content);
                        //释放掉内存
                        DataBufferUtils.release(dataBuffer);
                        String s = new String(content, Charset.forName("UTF-8"));
                        //TODO，s就是response的值，想修改、查看就随意而为了
                        byte[] uppedContent = new String(content, Charset.forName("UTF-8")).getBytes();
                        return bufferFactory.wrap(uppedContent);
                    }));
                }
                // if body is not a flux. never got there.
                return super.writeWith(body);
            }
        };
        // replace response with decorator
        return chain.filter(exchange.mutate().response(decoratedResponse).build());
    }
}

Answer 4

public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
/**
 *
 *
 * 1.获取请求信息
 *
 */
Route gatewayUrl = exchange.getRequiredAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
URI uri = gatewayUrl.getUri();
ServerHttpRequest request = (ServerHttpRequest)exchange.getRequest();

Answer 5

public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) { /**
 *
 *
 * 1.获取请求信息
 *
 */
Route gatewayUrl = exchange.getRequiredAttribute(ServerWebExchangeUtils.GATEWAY_ROUTE_ATTR);
URI uri = gatewayUrl.getUri();
ServerHttpRequest request = (ServerHttpRequest)exchange.getRequest();
HttpHeaders header = request.getHeaders();
        ServerHttpRequest.Builder mutate = request.mutate(); String rawPath = request.getURI().toString();
String path = request.getPath().value();
String method = request.getMethodValue();
String token = header.getFirst(JwtUtil.HEADER_AUTH);
String instance = uri.getAuthority(); System.out.println("*********************1.请求信息*******************");
System.out.println("RawPath:" + rawPath);
System.out.println("path:" + path);
System.out.println("method:" + method);
System.out.println("token:" + token);
System.out.println("instance:" + instance);
System.out.println("****************************************");