springcloud gateway 修改返回值body

求助问答
1

我自定义了个全局过滤器，代码如下，但程序没有进入重写的writeWith，需求就是修改response里的数据

package com.fawvw.ms.pt.cps.sas.isg.filter;

import com.alibaba.fastjson.JSON;
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.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.Charset;

@Component
public class ReBackDataFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        return operationExchange(exchange, chain);
    }

    private Mono<Void> operationExchange(ServerWebExchange exchange, GatewayFilterChain chain) {
        ServerHttpResponse response = exchange.getResponse();
        System.out.println("@Entry ReBackDataFilter filter response = 【"+ JSON.toJSONString(response) +"】");
        DataBufferFactory dataBufferFactory = response.bufferFactory();
        ServerHttpResponseDecorator responseDecorator = new ServerHttpResponseDecorator(response) {
            @Override
            public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                System.out.println("body = " + 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"));
                        System.out.println("s = " + s);
                        //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 dataBufferFactory.wrap(uppedContent);
                    }));
                }
                return super.writeWith(body);
            }
        };
        return chain.filter(exchange.mutate().response(response).build());
    }

    @Override
    public int getOrder() {
        return -2;
    }
}
2

你可以看看这个：