Spring-Cloud-Gateway 从升级到放弃

时间 2019-11-06 标签 spring cloud gateway 升级放弃

1 为何要升级为spring-cloud-gateway？

Spring Cloud Gateway features:java

Built on Spring Framework 5, Project Reactor and Spring Boot 2.0react
Able to match routes on any request attribute.web
Predicates and filters are specific to routes.spring
Hystrix Circuit Breaker integration.编程
Spring Cloud DiscoveryClient integrationjson
Easy to write Predicates and Filtersbootstrap
Request Rate Limiting缓存
Path Rewriting并发

这是官方说的，spring gateway相对spring zuul要新不少，应用也更加自由，开发体验更好。可是我在测试中发现，spring-cloud-gateway相对于zuul来讲，更加出众的仍是其性能，固然最后让我放弃的也是由于这一点。app

网上的朋友也有作一些gateway和zuul的性能比较，大多的结论也是gateway要优于zuul，同时也更加稳定。

可是咱们不能轻信，因此我也作了测试,这部分测试内容若不感兴趣能够跳过，zuul就不测试了。

2.spring-cloud-gateway的初步测试

　　step.1：测试准备：

　　　　1.gateway版本：2.0.1

　　　　2.服务主机：10.1.4.32，16G内存，4核虚拟机

　　　　3.测试客户端：10.1.4.34，16G内存，4核虚拟机

　　　　4.测试工具wrk

　　step.2：创建gateway工程并写两个测试http接口，

　　　　1.http://10.1.4.32:14077/hello [POST]

　　　　2.http://10.1.4.32:14077/test [GET]

　　step.3：开始测试

　　step.4：测试结果　　　

[wrk@localhost wrk]$ ./wrk  -t 15 -c500 -d 10 --latency  http://10.1.4.32:14077/test
Running 10s test @ http://10.1.4.32:14077/test
  15 threads and 500 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     3.38ms    3.26ms 113.45ms   95.76%
    Req/Sec    10.84k     1.44k   26.48k    89.50%
  Latency Distribution
     50%    2.79ms
     75%    3.51ms
     90%    4.21ms
     99%   17.23ms
  1625714 requests in 10.10s, 131.79MB read
Requests/sec: 160961.07
Transfer/sec:     13.05MB

以及：

[wrk@localhost wrk]$ ./wrk  -t 15 -c500 -d 10 --latency -s scripts/gateway.lua  http://10.1.4.32:14077/hello
Running 10s test @ http://10.1.4.32:14077/hello
  15 threads and 500 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     5.21ms    3.96ms 255.59ms   96.75%
    Req/Sec     6.62k   604.79    13.72k    88.48%
  Latency Distribution
     50%    4.78ms
     75%    5.55ms
     90%    6.32ms
     99%   14.87ms
  994374 requests in 10.10s, 539.59MB read
Requests/sec:  98471.14
Transfer/sec:     53.43MB

说明，若是测试结果差异较大多是由于测试工具的问题。

结果显示，POST方法的性能TPS达到了10W/s,而GET方法的性能TPS达到了16W/s。

这看起来很难以想象，由于正常的微服务，能达到2W/s的性能已是良好，达到10W实在是难以想象。可是前面说了spring-cloud-gateway引入了Spring Reactor反应式编程，应对的即是这种高并发需求。

固然，即使spring-cloud-gateway给了咱们很大惊喜，可是若是所以就引入了spring-cloud-gateway，那仍是会有些草率，毕竟gateway是用来干什么的？是路由和过滤。继续测试。

　　step.5：加上路由和过滤器,在配置文件中加入下面内容

spring:
  cloud:
    gateway:
      routes:
      - id: test
        uri: http://10.1.4.32:14077/test
        predicates:
        - Path=/tt
        filters:
        - AddRequestParameter=foo, bar

表示，给test方法加入了路由，而且加入了官方提供的过滤器：AddRequestParameter=foo, bar

　　step.6：测试，并附测试结果：

[wrk@localhost wrk]$ ./wrk  -t 15 -c500 -d 10 --latency  http://10.1.4.32:14077/tt
Running 10s test @ http://10.1.4.32:14077/tt
  15 threads and 500 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    18.99ms   12.15ms 122.69ms   70.84%
    Req/Sec     1.82k   155.77     2.36k    73.94%
  Latency Distribution
     50%   17.03ms
     75%   25.49ms
     90%   35.02ms
     99%   57.13ms
  274529 requests in 10.10s, 22.25MB read
Requests/sec:  27182.88
Transfer/sec:      2.20MB

性能只剩27000/s，貌似下降了不少，可是比起zuul仍然快了很多。由于在这台机器上，测试zuul或许都不能到达2W。

那么，是否是就应该使用spring-cloud-gateway了？

3.开始使用spring-cloud-gateway

在使用上spring-cluod-gateway以后，我开始编辑本身的过滤器，需求要求写两个过滤器，修改请求体和响应体。

由于须要对特定的请求使用过滤器，因此这里使用gateway-filter，有些代码官方有，有些网友提供，两个过滤器代码大体以下：

解密过滤器，pre：

package com.newland.dc.ctid.fileter;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.newland.dc.common.vo.RequestHeaderVo;
import com.newland.dc.ctid.entity.dto.RequestDto;
import io.netty.buffer.ByteBufAllocator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.core.io.buffer.NettyDataBufferFactory;
import org.springframework.core.style.ToStringCreator;
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.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import java.nio.CharBuffer;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;

/**
 * Created by garfield on 2019/2/26.
 */
@Component
public class DecryptGatewayFilterFactory extends AbstractGatewayFilterFactory<DecryptGatewayFilterFactory.Config>{

    private static Logger log = LoggerFactory.getLogger(DecryptGatewayFilterFactory.class);

    public static final String DECRYPT_HEADER = "decrypt_header";


    public DecryptGatewayFilterFactory() {
        super(Config.class);
    }


    private Gson gson = new GsonBuilder().serializeNulls().create();


    @Override
    @SuppressWarnings("unchecked")
    public GatewayFilter apply(Config config) {
        return new DecryptGatewayFilter(config);
    }

    public class DecryptGatewayFilter implements GatewayFilter, Ordered {
        Config config;

        DecryptGatewayFilter(Config config) {
            this.config = config;
        }
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
                log.debug(config.toString());
                ServerHttpRequest request = exchange.getRequest();
                MediaType contentType = request.getHeaders().getContentType();

                boolean postRequest = "POST".equalsIgnoreCase(request.getMethodValue()) && !contentType.toString().contains("multipart/form-data");
                //判断是否为POST请求
                if (postRequest) {

                    Flux<DataBuffer> body = request.getBody();
                    AtomicReference<String> bodyRef = new AtomicReference<>();//缓存读取的request body信息
                    body.subscribe(dataBuffer -> {
                        CharBuffer charBuffer = StandardCharsets.UTF_8.decode(dataBuffer.asByteBuffer());
                        DataBufferUtils.release(dataBuffer);
                        bodyRef.set(charBuffer.toString());
                    });//读取request body到缓存
                    String bodyStr = bodyRef.get();//获取request body
                    log.debug(bodyStr);//这里是咱们须要作的操做
                    RequestDto requestDto = gson.fromJson(bodyStr, RequestDto.class);
                    log.debug("decrypt filter");
                    //save header to response header
                    RequestHeaderVo headerVo = requestDto.getHeader();
                    headerVo.setAppVersion("1000");
                    //此处能够传递一些变量
                    exchange.getResponse().getHeaders().add(DECRYPT_HEADER, gson.toJson(headerVo));

                    DataBuffer bodyDataBuffer = stringBuffer(bodyStr);
                    Flux<DataBuffer> bodyFlux = Flux.just(bodyDataBuffer);

                    request = new ServerHttpRequestDecorator(request){
                        @Override
                        public Flux<DataBuffer> getBody() {
                            return bodyFlux;
                        }
                    };//封装咱们的request
                }
                return chain.filter(exchange.mutate().request(request.mutate().header("a","200").build()).build());
            };

        @Override
        public int getOrder() {
            return -10;
        }
    }

    public static DataBuffer stringBuffer(String value) {
        byte[] bytes = value.getBytes(StandardCharsets.UTF_8);

        NettyDataBufferFactory nettyDataBufferFactory = new NettyDataBufferFactory(ByteBufAllocator.DEFAULT);
        DataBuffer buffer = nettyDataBufferFactory.allocateBuffer(bytes.length);
        buffer.write(bytes);
        return buffer;
    }


    @Override
    public ServerHttpRequest.Builder mutate(ServerHttpRequest request) {
        return null;
    }

    public static class Config {
        private boolean decrypt;


        public boolean isDecrypt() {
            return decrypt;
        }

        public void setDecrypt(boolean decrypt) {
            this.decrypt = decrypt;
        }

        @Override
        public String toString() {
            return new ToStringCreator(this)
                    .append("decrypt", decrypt)
                    .toString();
        }
    }


    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("decrypt");
    }
}

View Code

加密过滤器，使用源码的提供的修改方法，post：

package com.newland.dc.ctid.fileter;

import com.google.gson.Gson;
import com.newland.dc.common.vo.RequestHeaderVo;
import com.newland.dc.ctid.entity.dto.RequestDto;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.cloud.gateway.filter.factory.rewrite.ModifyResponseBodyGatewayFilterFactory;
import org.springframework.core.style.ToStringCreator;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.util.Arrays;
import java.util.List;

/**
 * @Auther: garfield
 * @Date: 2019/3/5 15:33
 * @Description:
 */
@Component
public class AnGatewayFilterFactory extends AbstractGatewayFilterFactory<AnGatewayFilterFactory.Config> {


    private Gson gson = new Gson();

    public AnGatewayFilterFactory() {
        super(Config.class);
    }

    @Override
    public GatewayFilter apply(Config config) {

        ModifyResponseBodyGatewayFilterFactory m1 = new ModifyResponseBodyGatewayFilterFactory(null);
        ModifyResponseBodyGatewayFilterFactory.Config c1 = new ModifyResponseBodyGatewayFilterFactory.Config();
        c1.setInClass(String.class);
        c1.setOutClass(String.class);
        c1.setNewContentType("application/json");

        c1.setRewriteFunction((exchange, body) -> {
            ServerWebExchange ex = (ServerWebExchange) exchange;
            //此处更改响应体
            RequestHeaderVo requestHeaderVo = new RequestHeaderVo();
            RequestDto requestDto = gson.fromJson(body.toString(), RequestDto.class);
            requestDto.setHeader(requestHeaderVo);
            body = gson.toJson(requestDto);
            return Mono.just(body);
        });
        return m1.apply(c1);
    }

    public static class Config {
        private boolean decrypt;


        public boolean isDecrypt() {
            return decrypt;
        }

        public void setDecrypt(boolean decrypt) {
            this.decrypt = decrypt;
        }

        @Override
        public String toString() {
            return new ToStringCreator(this)
                    .append("encrypt", decrypt)
                    .toString();
        }
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("encrypt");
    }
}

View Code

这里须要转移一下话题，这个过滤器修改其实有几种方法，能够本身写，也能够应用源码提供的例子。上面的两种写法已经测试都能使用，其实我还有两种方式，大同小异就是了，但也准备贴出来，也记录一下问题：

下面这个其实就是源码中的例子，只不过不引用，本身写：

    @Override
        @SuppressWarnings("unchecked")
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

            ServerHttpResponseDecorator responseDecorator = new ServerHttpResponseDecorator(exchange.getResponse()) {
                @Override
                public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                    ServerHttpRequest request = exchange.getRequest();

                    MediaType originalResponseContentType = exchange.getAttribute(ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR);
                    HttpHeaders httpHeaders = new HttpHeaders();
                    httpHeaders.setContentType(originalResponseContentType);
                    ResponseAdapter responseAdapter = new ResponseAdapter(body, httpHeaders);
                    DefaultClientResponse clientResponse = new DefaultClientResponse(responseAdapter, ExchangeStrategies.withDefaults());

                    Mono<DataBuffer> modifiedBody = clientResponse.bodyToMono(DataBuffer.class).map(encrypt(config, new RequestHeaderVo()));

                    BodyInserter bodyInserter = BodyInserters.fromPublisher(modifiedBody, DataBuffer.class);
                    CachedBodyOutputMessage outputMessage = new CachedBodyOutputMessage(exchange, exchange.getResponse().getHeaders());
                    return bodyInserter.insert(outputMessage, new BodyInserterContext())
                            .then(Mono.defer(() -> {
                                Flux<DataBuffer> messageBody = outputMessage.getBody();
                                HttpHeaders headers = getDelegate().getHeaders();
                                if (headers.getContentLength() < 0 && !headers.containsKey(HttpHeaders.TRANSFER_ENCODING)) {
                                    messageBody = messageBody.doOnNext(data -> headers.setContentLength(data.readableByteCount()));
                                }
                                return this.getDelegate().writeWith(messageBody);
                            }));
                }

                @Override
                public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
                    return writeWith(Flux.from(body)
                            .flatMapSequential(p -> p));
                }
            };
            return chain.filter(exchange.mutate().response(responseDecorator).build());

        }

        @Override
        public int getOrder() {
            return NettyWriteResponseFilter.WRITE_RESPONSE_FILTER_ORDER - 1;
        }

    }

    private Function<DataBuffer, DataBuffer> encrypt(Config config, RequestHeaderVo headerVo) {
        if (config.encrypt) {
            return (i) -> {
                InputStream inputStream = i.asInputStream();

                byte[] bytes = new byte[0];
                try {
                    bytes = new byte[inputStream.available()];


                    inputStream.read(bytes);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                //进行咱们的操做
                String body = new String(bytes);
                log.debug("this is response encrypt");
                log.debug(body);
                log.debug(headerVo.toString());
//                body = encryptService.responseEncrypt(body, headerVo);

                //进行咱们的操做
                return i.write(TokenGatewayFilterFactory.stringBuffer(body));
//                return i.write(new String(body).getBytes());

            };


        } else {
            return i -> i;
        }

    }

View Code

这种例子中，发现修改response body的时候，会引发代码进入NioEventLoop类中的run方法，死循环没法退出，我也不清楚为何，修改需谨慎。

另外一种，跟这位网友写得差很少，只不过我没测试就是了：https://www.jianshu.com/p/9f00e0e1681c

        @Override
        @SuppressWarnings("unchecked")
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
            return chain.filter(exchange.mutate().response(new ServerHttpResponseDecorator(exchange.getResponse()) {
                @Override
                public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
                    DataBufferFactory bufferFactory = exchange.getResponse().bufferFactory();
                    if (getStatusCode().equals(HttpStatus.OK) && body instanceof Flux) {
                        Flux<? extends DataBuffer> fluxBody = Flux.first(body);
                        return super.writeWith(fluxBody.map(dataBuffer -> {
                            System.out.println(dataBuffer.readableByteCount());

                            byte[] content = new byte[dataBuffer.readableByteCount()];
                            dataBuffer.read(content);
                            //释放掉内存
                            DataBufferUtils.release(dataBuffer);
                            //responseData就是下游系统返回的内容,能够查看修改
                            String responseData = new String(content, Charset.forName("UTF-8"));

                            log.debug("响应内容:{}", responseData);
                            log.debug("this is response encrypt");
                            System.out.println(responseData);

                            byte[] newContent = responseData.getBytes();
//                body = encryptService.responseEncrypt(body, headerVo);
                            byte[] uppedContent = new String(newContent, Charset.forName("UTF-8")).getBytes();
                            return bufferFactory.wrap(uppedContent);
                        }));
                    } else {
                        log.error("响应code异常:{}", getStatusCode());
                    }
                    return super.writeWith(body);
                }
            }).build());
        }


        @Override
        public int getOrder() {
            return NettyWriteResponseFilter.WRITE_RESPONSE_FILTER_ORDER - 1;
        }
    }

View Code

这个方法会出现问题，body的截取长度常常没有彻底。

我原本是到这个网址下面寻找答案，做者是这样回复的：

　　上面只是简单的样例，FIux是发送多个数据的，当报文长时会拆分，处理一次只能拿到一部分报文，可使用Flux.toArray方法将数据聚合后处理，也能够参照https://www.jianshu.com/p/9b781fb1aaa0里面的响应处理。

确实是这个问题，因此咱们也能够仿照他的另一个例子写，你们能够到他的简书博客中去看，值得提醒的是，他的例子中，版本也是2.0.1,如果版本改成2.1以上，就不能用哦！

这里蛮贴一下：

package com.newland.dc.ctid.fileter;

import com.google.gson.Gson;
import com.newland.dc.common.vo.RequestHeaderVo;
import com.newland.dc.ctid.service.SecurityService;
import com.newland.dc.log.kafka.KafkaLog;
import org.reactivestreams.Publisher;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.NettyWriteResponseFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.cloud.gateway.support.*;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.style.ToStringCreator;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseCookie;
import org.springframework.http.client.reactive.ClientHttpResponse;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
import org.springframework.stereotype.Component;
import org.springframework.util.MultiValueMap;
import org.springframework.web.reactive.function.client.ExchangeStrategies;
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.io.IOException;
import java.io.InputStream;
import java.util.*;
import java.util.function.BiFunction;
import java.util.function.Function;

import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR;


/**
 * @Auther: garfield
 * @Date: 2019/2/28 上午10:45
 * @Description:
 */
@Component
public class EncryptGatewayFilterFactory extends AbstractGatewayFilterFactory<EncryptGatewayFilterFactory.Config> {

    private static Logger log = LoggerFactory.getLogger(EncryptGatewayFilterFactory.class);


    @Autowired
    private SecurityService encryptService;

    public EncryptGatewayFilterFactory() {
        super(Config.class);
    }


    //    private Gson gson = new GsonBuilder().serializeNulls().create();
    private Gson gson = new Gson();

    @Value("${server.host:10.10.10.10}")
    private String serverHost;

    @Value("${server.port}")
    private String serverPort;


    @Override
    @SuppressWarnings("unchecked")
    public GatewayFilter apply(Config config) {
        return new EncryptGatewayFilter(config);
    }


    @Override
    public ServerHttpRequest.Builder mutate(ServerHttpRequest request) {
        return null;
    }

    public static class Config {

        private boolean encrypt;

        public boolean isEncrypt() {
            return encrypt;
        }

        public Config setEncrypt(boolean encrypt) {
            this.encrypt = encrypt;
            return this;
        }

        @Override
        public String toString() {
            return new ToStringCreator(this)
                    .append("encrypt", encrypt)
                    .toString();
        }
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("encrypt");
    }

    public class EncryptGatewayFilter implements GatewayFilter, Ordered {
        Config config;

        EncryptGatewayFilter(Config config) {
            this.config = config;
        }

        @Override
        @SuppressWarnings("unchecked")
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
            String trace = exchange.getRequest().getHeaders().getFirst("trace");
            ServerRequest serverRequest = new DefaultServerRequest(exchange);
            return serverRequest.bodyToMono(String.class).flatMap(reqBody -> {
                //重写原始请求
                ServerHttpRequestDecorator decorator = new ServerHttpRequestDecorator(exchange.getRequest()) {
                    @Override
                    public HttpHeaders getHeaders() {
                        HttpHeaders httpHeaders = new HttpHeaders();
                        httpHeaders.putAll(super.getHeaders());
                        return httpHeaders;
                    }

                    @Override
                    public Flux<DataBuffer> getBody() {
                        //打印原始请求日志
                        log.info("[Trace:{}]-gateway request:headers=[{}],body=[{}]", trace, getHeaders(), reqBody);
                        return Flux.just(reqBody).map(bx -> exchange.getResponse().bufferFactory().wrap(bx.getBytes()));
                    }
                };
                //重写原始响应
                BodyHandlerServerHttpResponseDecorator responseDecorator = new BodyHandlerServerHttpResponseDecorator(
                        initBodyHandler(exchange), exchange.getResponse());

                return chain.filter(exchange.mutate().request(decorator).response(responseDecorator).build());
            });
        }

        @Override
        public int getOrder() {
            return NettyWriteResponseFilter.WRITE_RESPONSE_FILTER_ORDER - 1;
        }

    }

    public interface BodyHandlerFunction
            extends BiFunction<ServerHttpResponse, Publisher<? extends DataBuffer>, Mono<Void>> {
    }

    protected BodyHandlerFunction initBodyHandler(ServerWebExchange exchange) {
        return (resp, body) -> {
            //拦截
            MediaType originalResponseContentType = exchange.getAttribute(ORIGINAL_RESPONSE_CONTENT_TYPE_ATTR);
            HttpHeaders httpHeaders = new HttpHeaders();
            httpHeaders.setContentType(originalResponseContentType);
            DefaultClientResponseAdapter clientResponseAdapter = new DefaultClientResponseAdapter(body, httpHeaders);
            Mono<String> bodyMono = clientResponseAdapter.bodyToMono(String.class);
            //此处能够得到前面放置的参数
            return bodyMono.flatMap((respBody) -> {
//                打印返回响应日志
                System.out.println(respBody);
                return resp.writeWith(Flux.just(respBody).map(bx -> resp.bufferFactory().wrap(bx.getBytes())));
            }).then();
        };
    }

 
    public static class DefaultClientResponseAdapter extends DefaultClientResponse {

        /**
         * @param body
         * @param httpHeaders
         */
        public DefaultClientResponseAdapter(Publisher<? extends DataBuffer> body,
                                            HttpHeaders httpHeaders) {
            this(new ResponseAdapter(body, httpHeaders),
                    ExchangeStrategies.withDefaults());
        }

        /**
         * @param response
         * @param strategies
         */
        public DefaultClientResponseAdapter(ClientHttpResponse response,
                                            ExchangeStrategies strategies) {
            super(response, strategies);
        }

        /**
         * ClientHttpResponse 适配器
         */
        static class ResponseAdapter implements ClientHttpResponse {
            /**
             * 响应数据
             */
            private final Flux<DataBuffer> flux;
            /**
             *
             */
            private final HttpHeaders headers;

            public ResponseAdapter(Publisher<? extends DataBuffer> body,
                                   HttpHeaders headers) {
                this.headers = headers;
                if (body instanceof Flux) {
                    flux = (Flux) body;
                } else {
                    flux = ((Mono) body).flux();
                }
            }

            @Override
            public Flux<DataBuffer> getBody() {
                return flux;
            }

            @Override
            public HttpHeaders getHeaders() {
                return headers;
            }

            @Override
            public HttpStatus getStatusCode() {
                return null;
            }

            @Override
            public int getRawStatusCode() {
                return 0;
            }

            @Override
            public MultiValueMap<String, ResponseCookie> getCookies() {
                return null;
            }
        }
    }

    class BodyHandlerServerHttpResponseDecorator extends ServerHttpResponseDecorator {

        /**
         * body 处理拦截器
         */
        private BodyHandlerFunction bodyHandler = initDefaultBodyHandler();

        /**
         * 构造函数
         *
         * @param bodyHandler
         * @param delegate
         */
        public BodyHandlerServerHttpResponseDecorator(BodyHandlerFunction bodyHandler, ServerHttpResponse delegate) {
            super(delegate);
            if (bodyHandler != null) {
                this.bodyHandler = bodyHandler;
            }
        }

        @Override
        public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
            //body 拦截处理器处理响应
            return bodyHandler.apply(getDelegate(), body);
        }

        @Override
        public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
            return writeWith(Flux.from(body).flatMapSequential(p -> p));
        }

        /**
         * 默认body拦截处理器
         *
         * @return
         */
        private BodyHandlerFunction initDefaultBodyHandler() {
            return (resp, body) -> resp.writeWith(body);
        }
    }
}

View Code

那么万事具有，代码都写好了，咱们又须要进行性能测试。这边要记住，我用的是官方的那个例子，其余的写法也用过了，可是结果差很少。

4.再一次测试spring-cloud-gateway 网关路由性能

　　step.1：性能测试，改一下配置，表示加入了过滤器。这里为何只有一个过滤器，由于这个过滤器问题比较大，过程就略过了。

      - id: an
        uri: http://10.1.4.32:14077/hello
        predicates:
        - Path=/an
        filters:
        - An

　　通过屡次测试，其余的过滤器都还好，只有修改response body的过滤器，严重影响性能，且有读写错误。

　　step.2：测试，以及测试结果

[wrk@localhost wrk]$ ./wrk  -t 15 -c500 -d 10 --latency -s scripts/gateway.lua  http://10.1.4.32:14077/an
Running 10s test @ http://10.1.4.32:14077/an
  15 threads and 500 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     1.03s   488.75ms   2.00s    60.62%
    Req/Sec    26.59     13.84    80.00     67.60%
  Latency Distribution
     50%  931.54ms
     75%    1.45s
     90%    1.76s
     99%    1.97s
  3848 requests in 10.10s, 1.64MB read
  Socket errors: connect 0, read 0, write 0, timeout 458
Requests/sec:    381.05
Transfer/sec:    166.71KB

结果多出一行，socket错误，并且仍是超时,并且，日志中也存在错误：

2019-03-06T16:09:33,396|INFO ||AsyncResolver-bootstrap-executor-0||||Resolving eureka endpoints via configuration
2019-03-06T16:10:38,268|ERROR||reactor-http-server-epoll-18||||Unhandled failure: Connection has been closed, response already set (status=200)
2019-03-06T16:10:38,268|WARN ||reactor-http-server-epoll-18||||Handling completed with error: Connection has been closed
2019-03-06T16:10:38,269|ERROR||reactor-http-server-epoll-18||||Unhandled failure: null, response already set (status=200)
2019-03-06T16:10:38,269|WARN ||reactor-http-server-epoll-18||||Handling completed with error: null
2019-03-06T16:10:38,294|ERROR||reactor-http-server-epoll-18||||Unhandled failure: syscall:write(..) failed: 断开的管道, response already set (status=null)
2019-03-06T16:10:38,294|WARN ||reactor-http-server-epoll-18||||Handling completed with error: syscall:write(..) failed: 断开的管道
2019-03-06T16:10:38,306|ERROR||reactor-http-server-epoll-23||||Unhandled failure: syscall:write(..) failed: 断开的管道, response already set (status=null)
2019-03-06T16:10:38,306|WARN ||reactor-http-server-epoll-23||||Handling completed with error: syscall:write(..) failed: 断开的管道
2019-03-06T16:14:33,397|INFO ||AsyncResolver-bootstrap-executor-0||||Resolving eureka endpoints via configuration

这个问题很严重了，由于单个请求的时候，并不会报错，这个错误只发生在高并发压测下，没法追踪。最重要的是，咱们看到性能只剩下300/s，这是万万不能接受的，生产更不能接收。

这个问题很难解释，由于咱们采用的是官方提供的写法，咱们回头看官方的修改response 类，好吧，不用看了，由于：

package org.springframework.cloud.gateway.filter.factory.rewrite;
/**
 * This filter is BETA and may be subject to change in a future release.
 */
public class ModifyResponseBodyGatewayFilterFactory
        extends AbstractGatewayFilterFactory<ModifyResponseBodyGatewayFilterFactory.Config> {

官方已经说了，这是测试版本，不顶用。

不死心，又想起了gateway提供的GlobalFilter，将刚才的代码写到全局过滤器中再试试，可是结果相同！

凉凉...

跪求结论跟我不一样的启发文档，或者只能等下一版本了。